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Sample records for streptococci streptococcus mitis

  1. Mitis group streptococci express variable pilus islet 2 pili.

    Science.gov (United States)

    Zähner, Dorothea; Gandhi, Ashish R; Yi, Hong; Stephens, David S

    2011-01-01

    Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguinis are members of the Mitis group of streptococci and agents of oral biofilm, dental plaque and infective endocarditis, disease processes that involve bacteria-bacteria and bacteria-host interactions. Their close relative, the human pathogen S. pneumoniae uses pilus-islet 2 (PI-2)-encoded pili to facilitate adhesion to eukaryotic cells. PI-2 pilus-encoding genetic islets were identified in S. oralis, S. mitis, and S. sanguinis, but were absent from other isolates of these species. The PI-2 islets resembled the genetic organization of the PI-2 islet of S. pneumoniae, but differed in the genes encoding the structural pilus proteins PitA and PitB. Two and three variants of pitA (a pseudogene in S. pneumoniae) and pitB, respectively, were identified that showed ≈20% difference in nucleotide as well as corresponding protein sequence. Species-independent combinations of pitA and pitB variants indicated prior intra- and interspecies horizontal gene transfer events. Polyclonal antisera developed against PitA and PitB of S. oralis type strain ATCC35037 revealed that PI-2 pili in oral streptococci were composed of PitA and PitB. Electronmicrographs showed pilus structures radiating >700 nm from the bacterial surface in the wild type strain, but not in an isogenic PI-2 deletion mutant. Anti-PitB-antiserum only reacted with pili containing the same PitB variant, whereas anti-PitA antiserum was cross-reactive with the other PitA variant. Electronic multilocus sequence analysis revealed that all PI-2-encoding oral streptococci were closely-related and cluster with non-PI-2-encoding S. oralis strains. This is the first identification of PI-2 pili in Mitis group oral streptococci. The findings provide a striking example of intra- and interspecies horizontal gene transfer. The PI-2 pilus diversity provides a possible key to link strain-specific bacterial interactions and/or tissue tropisms with pathogenic traits

  2. Mitis group streptococci express variable pilus islet 2 pili.

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    Dorothea Zähner

    Full Text Available Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguinis are members of the Mitis group of streptococci and agents of oral biofilm, dental plaque and infective endocarditis, disease processes that involve bacteria-bacteria and bacteria-host interactions. Their close relative, the human pathogen S. pneumoniae uses pilus-islet 2 (PI-2-encoded pili to facilitate adhesion to eukaryotic cells.PI-2 pilus-encoding genetic islets were identified in S. oralis, S. mitis, and S. sanguinis, but were absent from other isolates of these species. The PI-2 islets resembled the genetic organization of the PI-2 islet of S. pneumoniae, but differed in the genes encoding the structural pilus proteins PitA and PitB. Two and three variants of pitA (a pseudogene in S. pneumoniae and pitB, respectively, were identified that showed ≈20% difference in nucleotide as well as corresponding protein sequence. Species-independent combinations of pitA and pitB variants indicated prior intra- and interspecies horizontal gene transfer events. Polyclonal antisera developed against PitA and PitB of S. oralis type strain ATCC35037 revealed that PI-2 pili in oral streptococci were composed of PitA and PitB. Electronmicrographs showed pilus structures radiating >700 nm from the bacterial surface in the wild type strain, but not in an isogenic PI-2 deletion mutant. Anti-PitB-antiserum only reacted with pili containing the same PitB variant, whereas anti-PitA antiserum was cross-reactive with the other PitA variant. Electronic multilocus sequence analysis revealed that all PI-2-encoding oral streptococci were closely-related and cluster with non-PI-2-encoding S. oralis strains.This is the first identification of PI-2 pili in Mitis group oral streptococci. The findings provide a striking example of intra- and interspecies horizontal gene transfer. The PI-2 pilus diversity provides a possible key to link strain-specific bacterial interactions and/or tissue tropisms with

  3. StreptoBase: An Oral Streptococcus mitis Group Genomic Resource and Analysis Platform.

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    Wenning Zheng

    Full Text Available The oral streptococci are spherical Gram-positive bacteria categorized under the phylum Firmicutes which are among the most common causative agents of bacterial infective endocarditis (IE and are also important agents in septicaemia in neutropenic patients. The Streptococcus mitis group is comprised of 13 species including some of the most common human oral colonizers such as S. mitis, S. oralis, S. sanguinis and S. gordonii as well as species such as S. tigurinus, S. oligofermentans and S. australis that have only recently been classified and are poorly understood at present. We present StreptoBase, which provides a specialized free resource focusing on the genomic analyses of oral species from the mitis group. It currently hosts 104 S. mitis group genomes including 27 novel mitis group strains that we sequenced using the high throughput Illumina HiSeq technology platform, and provides a comprehensive set of genome sequences for analyses, particularly comparative analyses and visualization of both cross-species and cross-strain characteristics of S. mitis group bacteria. StreptoBase incorporates sophisticated in-house designed bioinformatics web tools such as Pairwise Genome Comparison (PGC tool and Pathogenomic Profiling Tool (PathoProT, which facilitate comparative pathogenomics analysis of Streptococcus strains. Examples are provided to demonstrate how StreptoBase can be employed to compare genome structure of different S. mitis group bacteria and putative virulence genes profile across multiple streptococcal strains. In conclusion, StreptoBase offers access to a range of streptococci genomic resources as well as analysis tools and will be an invaluable platform to accelerate research in streptococci. Database URL: http://streptococcus.um.edu.my.

  4. StreptoBase: An Oral Streptococcus mitis Group Genomic Resource and Analysis Platform.

    Science.gov (United States)

    Zheng, Wenning; Tan, Tze King; Paterson, Ian C; Mutha, Naresh V R; Siow, Cheuk Chuen; Tan, Shi Yang; Old, Lesley A; Jakubovics, Nicholas S; Choo, Siew Woh

    2016-01-01

    The oral streptococci are spherical Gram-positive bacteria categorized under the phylum Firmicutes which are among the most common causative agents of bacterial infective endocarditis (IE) and are also important agents in septicaemia in neutropenic patients. The Streptococcus mitis group is comprised of 13 species including some of the most common human oral colonizers such as S. mitis, S. oralis, S. sanguinis and S. gordonii as well as species such as S. tigurinus, S. oligofermentans and S. australis that have only recently been classified and are poorly understood at present. We present StreptoBase, which provides a specialized free resource focusing on the genomic analyses of oral species from the mitis group. It currently hosts 104 S. mitis group genomes including 27 novel mitis group strains that we sequenced using the high throughput Illumina HiSeq technology platform, and provides a comprehensive set of genome sequences for analyses, particularly comparative analyses and visualization of both cross-species and cross-strain characteristics of S. mitis group bacteria. StreptoBase incorporates sophisticated in-house designed bioinformatics web tools such as Pairwise Genome Comparison (PGC) tool and Pathogenomic Profiling Tool (PathoProT), which facilitate comparative pathogenomics analysis of Streptococcus strains. Examples are provided to demonstrate how StreptoBase can be employed to compare genome structure of different S. mitis group bacteria and putative virulence genes profile across multiple streptococcal strains. In conclusion, StreptoBase offers access to a range of streptococci genomic resources as well as analysis tools and will be an invaluable platform to accelerate research in streptococci. Database URL: http://streptococcus.um.edu.my.

  5. Isolation of Streptococcus tigurinus - a novel member of Streptococcus mitis group from a case of periodontitis.

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    Dhotre, Shree V; Mehetre, Gajanan T; Dharne, Mahesh S; Suryawanshi, Namdev M; Nagoba, Basavraj S

    2014-08-01

    Streptococcus tigurinus is a new member of the Streptococcus viridians group and is closely related to Streptococcus mitis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae, Streptococcus oralis, and Streptococcus infantis. The type strain AZ_3a(T) of S. tigurinus was originally isolated from a patient with infective endocarditis. Accurate identification of S. tigurinus is facilitated only by newer molecular methods like 16S rRNA gene analysis. During the course of study on bacteraemia and infective endocarditis with reference to periodontitis and viridians group of streptococci, a strain of S. tigurinus isolated from subgingival plaque of a patient with periodontitis identified by 16S rRNA gene analysis, which was originally identified as Streptococcus pluranimalium by Vitek 2. Confirmation by 16S rRNA gene analysis showed 99.39% similarity (1476/1485 bp) with S. tigurinus AZ_3a(T) (AORU01000002). To the best of our knowledge, this is the first report of isolation of S. tigurinus from the oral cavity of a periodontitis patient. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  6. J-GLOBAL MeSH Dictionary: Streptococcus mitis [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term Streptococcus mitis 名詞 一般 * * * * Streptococcus mit...is ... MeSH D034361 200906051281920120 C LS07 UNKNOWN_2 Streptococcus mitis

  7. In silico assessment of virulence factors in strains of Streptococcus oralis and Streptococcus mitis isolated from patients with Infective Endocarditis

    DEFF Research Database (Denmark)

    Rasmussen, Louise H.; Iversen, Katrine Højholt; Dargis, Rimtas

    2017-01-01

    Streptococcus oralis and Streptococcus mitis belong to the Mitis group, which are mostly commensals in the human oral cavity. Even though S. oralis and S. mitis are oral commensals, they can be opportunistic pathogens causing infective endocarditis. A recent taxonomic re-evaluation of the Mitis...

  8. An Unusual Cause of Flexor Tenosynovitis: Streptococcus mitis

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    Ulucay, Cağatay; Ozler, Turhan

    2014-01-01

    Summary: Streptococcus mitis is a commensal organism of the human oropharynx that rarely causes infection in healthy individuals. Herein, we describe a previously healthy 35-year-old woman who presented with acute pyogenic flexor tenosynovitis of the left index finger due to S. mitis infection. The patient’s infection was treated successfully via surgical and medical interventions, and during follow-up, it was determined that she was complement component C3 deficient. Tenosynovitis is an emergent clinical syndrome that can result in permanent disability or amputation. To the best of our knowledge, this case report is the first to describe tenosynovitis due to S. mitis; in addition, it highlights the importance of initiating therapy with antibiotics that are effective against this rare pathogen. PMID:25587497

  9. An Unusual Cause of Flexor Tenosynovitis: Streptococcus mitis

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    Ugur Anil Bingol, MD

    2014-12-01

    Full Text Available Summary: Streptococcus mitis is a commensal organism of the human oropharynx that rarely causes infection in healthy individuals. Herein, we describe a previously healthy 35-year-old woman who presented with acute pyogenic flexor tenosynovitis of the left index finger due to S. mitis infection. The patient’s infection was treated successfully via surgical and medical interventions, and during follow-up, it was determined that she was complement component C3 deficient. Tenosynovitis is an emergent clinical syndrome that can result in permanent disability or amputation. To the best of our knowledge, this case report is the first to describe tenosynovitis due to S. mitis; in addition, it highlights the importance of initiating therapy with antibiotics that are effective against this rare pathogen.

  10. Successful management of late-onset Streptococcus mitis endophthalmitis

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    Chon J

    2017-10-01

    Full Text Available Jinmann Chon,1 Moosang Kim2 1Department of Rehabilitation Medicine, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, 2Department of Ophthalmology, School of Medcine, Kangwon National University, Chuncheon, Korea Abstract: Endophthalmitis following intraocular surgery can be devastating. This case report demonstrates successful management of late-onset Streptococcus mitis endophthalmitis treated by vitrectomy, panretinal photocoagulation (PRP and silicone oil tamponade. A 75-year-old man presented with painful vision loss in his right eye. The patient had uneventful phacoemulsification and intraocular lens implantation in the right eye at an outside clinic 6 weeks prior. Examination disclosed hypopyon and vitritis, as well as discrete inflammatory collections in the vitreous. The patient underwent vitrectomy with PRP and silicone oil tamponade. Vitreous cultures were positive for S. mitis, a pathogen associated with severe tissue damage and poor clinical outcomes. One month after the surgery, intraocular inflammation was stabilized, and visual acuity was improved from light perception to 20/200. Aggressive surgical management may play a role in improving outcomes in these patients. Keywords: late-onset endophthalmitis, Streptococcus mitis, vitrectomy 

  11. Whole genome sequencing as a tool for phylogenetic analysis of clinical strains of Mitis group streptococci

    DEFF Research Database (Denmark)

    Rasmusen, L. H.; Dargis, R.; Iversen, Katrine Højholt

    2016-01-01

    observed in single gene analyses. Species identification based on single gene analysis showed their limitations when more strains were included. In contrast, analyses incorporating more sequence data, like MLSA, SNPs and core-genome analyses, provided more distinct clustering. The core-genome tree showed......Identification of Mitis group streptococci (MGS) to the species level is challenging for routine microbiology laboratories. Correct identification is crucial for the diagnosis of infective endocarditis, identification of treatment failure, and/or infection relapse. Eighty MGS from Danish patients...

  12. [Meningitis and white matter lesions due to Streptococcus mitis in a previously healthy child].

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    Yiş, Reyhan; Yüksel, Ciğdem Nükhet; Derundere, Umit; Yiş, Uluç

    2011-10-01

    Streptococcus mitis, an important member of viridans streptococci, is found in the normal flora of the oropharynx, gastrointestinal tract, female genital tract and skin. Although it is of low pathogenicity and virulence, it may cause serious infections in immunocompromised patients. Meningitis caused by S.mitis has been described in patients with previous spinal anesthesia, neurosurgical procedure, malignancy, bacterial endocarditis with neurological complications and alcoholics, but it is rare in patients who are previously healthy. In this report, a rare case of meningoencephalitis caused by S.mitis developed in a previously healthy child has been presented. A previously healthy eight-year-old girl who presented with fever, altered state of consciousness, and headache was hospitalized in intensive care unit with the diagnosis of meningitis. Past history revealed that she was treated with amoxicillin-clavulanate for acute sinusitis ten days before her admission. Whole blood count revealed the followings: hemoglobin 13 g/dl, white blood cell count 18.6 x 109/L (90% neutrophils), platelet count 200 x 109/L and 150 leucocytes were detected on cerebrospinal fluid (CSF) examination. Protein and glucose levels of CSF were 80 mg/dl and 40 mg/dl (concomitant blood glucose 100 mg/dl), respectively. Brain magnetic resonance imaging (MRI) revealed widespread white matter lesions, and alpha-hemolytic streptococci were grown in CSF culture. The isolate was identified as S.mitis with conventional methods, and also confirmed by VITEK2 (bioMerieux, France) and API 20 STREP (bioMerieux, France) systems. Isolate was found susceptible to penicillin, erythromycin, clindamycin, tetracycline, cefotaxime, vancomycin and chloramphenicol. Regarding the etiology, echocardiography revealed no vegetation nor valve pathology, and peripheral blood smear showed no abnormality. Immunoglobulin and complement levels were within normal limits. Ongoing inflammation in maxillary sinuses detected in

  13. Meningitis caused by streptococci other than Streptococcus pneumoniae: a retrospective clinical study

    DEFF Research Database (Denmark)

    Møller, Kirsten; Harder, Eva; Wandall, Johan

    1999-01-01

    We reviewed the medical records of 26 patients (median age 62 years, range 5-76 years) admitted to our institution during 1978-98 with acute bacterial meningitis (ABM) caused by streptococci other than Streptococcus pneumoniae (comprising 1.9% of all patients with ABM). 19 cases were community......-acquired and 7 were nosocomial. 73% had comorbid or predisposing conditions and 73% had an identifiable extracerebral focus; only in 2 patients no comorbid disease, primary focus or predisposing condition was present. Five patients had cerebral abscesses, and 5 had endocarditis. Beta-haemolytic streptococci were...... grown in 14 cases (serotype A: 4, B: 5, C: 1, G: 4) and were predominant among patients with endocarditis, whereas alpha- or non-haemolytic strains grew in 12 cases (S. mitis: 4, S. constellatus: 2, E. faecalis: 2, S. bovis: 1, unspecified: 3) and were predominant in patients with a brain abscess...

  14. Antimicrobial effects of herbal extracts on Streptococcus mutans and normal oral streptococci.

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    Lee, Sung-Hoon

    2013-08-01

    Streptococcus mutans is associated with dental caries. A cariogenic biofilm, in particular, has been studied extensively for its role in the formation of dental caries. Herbal extracts such as Cudrania tricuspidata, Sophora flavescens, Ginkgo biloba, and Betula Schmidtii have been used as a folk remedy for treating diseases. The purpose of this study was to evaluate and compare the antibacterial activity of herbal extracts against normal oral streptococci, planktonic and biofilm of S. mutans. Streptococcus gordonii, Streptococcus oralis, Streptococcus salivarius, Streptococcus sanguinis, and S. mutans were cultivated with brain heart infusion broth and susceptibility assay for the herbal extracts was performed according to the protocol of Clinical and Laboratory Standard Institute. Also, S. mutans biofilm was formed on a polystyrene 12-well plate and 8-well chamber glass slip using BHI broth containing 2% sucrose and 1% mannose after conditioning the plate and the glass slip with unstimulated saliva. The biofilm was treated with the herbal extracts in various concentrations and inoculated on Mitis-Salivarius bacitracin agar plate for enumeration of viable S. mutans by counting colony forming units. Planktonic S. mutans showed susceptibility to all of the extracts and S. mutans biofilm exhibited the highest level of sensitivity for the extracts of S. flavescens. The normal oral streptococci exhibited a weak susceptibility in comparison to S. mutans. S. oralis, however, was resistant to all of the extracts. In conclusion, the extract of S. flavescens may be a potential candidate for prevention and management of dental caries.

  15. Delineation of Streptococcus dysgalactiae, its subspecies, and its clinical and phylogenetic relationship to Streptococcus pyogenes

    DEFF Research Database (Denmark)

    Jensen, Anders; Kilian, Mogens

    2011-01-01

    The close phylogenetic relationship of the important pathogen Streptococcus pneumoniae and several species of commensal streptococci, particularly Streptococcus mitis and Streptococcus pseudopneumoniae, and the recently demonstrated sharing of genes and phenotypic traits previously considered...

  16. Re-evaluation of the taxonomy of the Mitis group of the genus Streptococcus based on whole genome phylogenetic analyses, and proposed reclassification of Streptococcus dentisani as Streptococcus oralis subsp. dentisani comb. nov., Streptococcus tigurinus as Streptococcus oralis subsp. tigurinus comb. nov., and Streptococcus oligofermentans as a later synonym of Streptococcus cristatus.

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    Jensen, Anders; Scholz, Christian F P; Kilian, Mogens

    2016-11-01

    The Mitis group of the genus Streptococcus currently comprises 20 species with validly published names, including the pathogen S. pneumoniae. They have been the subject of much taxonomic confusion, due to phenotypic overlap and genetic heterogeneity, which has hampered a full appreciation of their clinical significance. The purpose of this study was to critically re-examine the taxonomy of the Mitis group using 195 publicly available genomes, including designated type strains for phylogenetic analyses based on core genomes, multilocus sequences and 16S rRNA gene sequences, combined with estimates of average nucleotide identity (ANI) and in silico and in vitro analyses of specific phenotypic characteristics. Our core genomic phylogenetic analyses revealed distinct clades that, to some extent, and from the clustering of type strains represent known species. However, many of the genomes have been incorrectly identified adding to the current confusion. Furthermore, our data show that 16S rRNA gene sequences and ANI are unsuitable for identifying and circumscribing new species of the Mitis group of the genus Streptococci. Based on the clustering patterns resulting from core genome phylogenetic analysis, we conclude that S. oligofermentans is a later synonym of S. cristatus. The recently described strains of the species Streptococcus dentisani includes one previously referred to as 'S. mitis biovar 2'. Together with S. oralis, S. dentisani and S. tigurinus form subclusters within a coherent phylogenetic clade. We propose that the species S. oralis consists of three subspecies: S. oralis subsp. oralis subsp. nov., S. oralis subsp. tigurinus comb. nov., and S. oralis subsp. dentisani comb. nov.

  17. Peripheral ischaemic retinopathy and neovascularisation in a patient with subacute streptococcus mitis-induced bacterial endocarditis

    OpenAIRE

    Leysen, LS; Kreps, EO; De Schryver, I; Hoornaert, KP; Smith, V; De Zaeytijd, J

    2017-01-01

    Objective: To describe a patient with peripheral retinal ischaemia and neovascularisation who was diagnosed with streptococcus mitis-induced bacterial endocarditis. Methods: Retrospective analysis of case report. A 57-year-old man presented with a history of a rapidly progressive, bilateral, painless visual loss. He also suffered from pain in the neck and lower back and a weight loss of 10 kg. He underwent a full ophthalmologic work-up, laboratory investigations, and imaging of the spine.R...

  18. Levofloxacin-resistant-Streptococcus mitis endophthalmitis: a unique presentation of bacterial endocarditis.

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    Dinani, Amreen; Ktaich, Nessrine; Urban, Carl; Rubin, David

    2009-10-01

    Endogenous endophthalmitis is a rare complication of infective endocarditis and has been decreasing due to the availability of effective antibiotics. We highlight a case of endogenous endophthalmitis due to levofloxacin-resistant Streptococcus mitis presenting as infective endocarditis. Endogenous endophthalmitis should be considered as a manifestation of an underlying systemic disease, especially in patients who present with non-specific signs and symptoms with no obvious source of precipitating infection.

  19. Capsular typing of Streptococcus agalactiae (Lancefield group B streptococci) from fish using multiplex PCR and serotyping

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    Streptococcus spp. including Streptococcus agalactiae (Lancefield group B streptococci) are considered emerging pathogens responsible for approximately $1 billion USD in annual losses to the global tilapia (Oreochromis sp.) aquaculture industry. This study evaluated a published multiplex PCR capsul...

  20. Splenic and kidney infarct: Sequelae of subacute Streptococcus mitis bacterial endocarditis

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    Sushilkumar Satish Gupta

    2017-01-01

    Full Text Available Infective endocarditis (IE is caused due to the vegetation on the heart valves, myocardium wall, or the pacemaker leads. Vegetation is a lesion that appears as a consequence of successive deposition of platelets and fibrin on the endothelial surface of the heart. Colonies of microbes can be usually found under the vegetation. Heart valves are involved more frequently as compared to other places. Streptococcus miti s, formerly known as S. mitior, is a commensal of the oral flora, however, if there of loss of integrity of the mucous membrane, the infection may disseminate to the blood flow. We describe here a rare presentation of S. mitis, causing IE and its complications in an immunocompetent patient.

  1. Infective endocarditis caused by multidrug-resistant Streptococcus mitis in a combined immunocompromised patient: an autopsy case report.

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    Matsui, Natsuko; Ito, Makoto; Kuramae, Hitoshi; Inukai, Tomomi; Sakai, Akiyoshi; Okugawa, Masaru

    2013-04-01

    An autopsy case of infective endocarditis caused by multidrug-resistant Streptococcus mitis was described in a patient with a combination of factors that compromised immune status, including autoimmune hemolytic anemia, post-splenectomy state, prolonged steroid treatment, and IgA deficiency. The isolated S. mitis strain from blood culture was broadly resistant to penicillin, cephalosporins, carbapenem, macrolides, and fluoroquinolone. Recurrent episodes of bacterial infections and therapeutic use of several antibiotics may underlie the development of multidrug resistance for S. mitis. Because clinically isolated S. mitis strains from chronically immunocompromised patients have become resistant to a wide spectrum of antibiotics, appropriate antibiotic regimens should be selected when treating invasive S. mitis infections in these compromised patients.

  2. Hip adductor pyomyositis from Streptococcus mitis in a four-year-old child.

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    Buldu, Metin Tolga; Raman, Raghu

    2016-01-01

    The unique aspect of this case study is the unusual history, presentation, ultrasonography, MRI and blood culture results, which lead to the diagnosis and treatment of adductor pyomyositis with a rare organism in a temperate country. The patient presented with a one-day history of malaise, fever, left groin pain and inability to weight bear on the left leg. There was no history of any trauma, predisposing infections or recent travel. Plain radiograph and ultrasound of the hip was normal with no effusion. Two consecutive blood cultures suggested Streptococcus mitis bacteraemia and MRI scan confirmed pyomyositis of the left hip adductors that was too small to drain. S. mitis is a normal commensal organism however it can lead to opportunistic infections particularly endocarditis. Echocardiogram revealed no cardiac complications, in particular no endocarditic vegetation. Patient was treated with intravenous benzylpenicillin for a week followed by oral phenoxymethylpenicillin for a week. Adductor pyomyositis must be considered as a differential diagnosis in a child with unusual presentation of hip pain. When an ultrasound is normal, MRI scan is warranted to confirm diagnosis. Septic screen should include blood cultures. The commonest causative organisms are the Staphylococcus family. However if S. mitis is isolated, cardiac sources of infection resulting in septic emboli must be investigated. Repeated MRI scans are required particularly if the patient does not respond to medical management. IV.

  3. Identification of non-streptococcal organisms from human dental plaque grown on the Streptococcus-selective medium mitis-salivarius agar.

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    Kim, Yeon-Hee; Lee, Si Young

    2015-02-01

    Mitis-salivarius (MS) agar has been used widely in microbial epidemiological studies because oral viridans streptococci can be selectively grown on this medium. Even though the previous findings reported the limited selecting power of MS agar for streptococcus strains, the identities of non-streptococcal strains from human oral samples which can grow on this medium are not clear yet. In this study, we identified non-streptococcal organisms grown on MS agar plates by polymerase chain reaction (PCR) amplification and sequencing of the 16S ribosomal RNA (rRNA) gene. Eighty bacterial colonies on MS plates were isolated from plaque samples, and bacterial identification was achieved with the rapid ID 32 Strep system and mini API reader. The bacterial colonies identified as non-streptococci by the API system were selected for further identification. The 16S rRNA gene was amplified by PCR and verified using DNA sequencing analysis for identification. Sequences were compared with those of reference organisms in the genome database of the National Center for Biotechnology Information using the Basic Local Alignment Search Tool (BLAST). Among the 11 isolated non-streptococcal strains on MS plates, 3 strains were identified as Actinomyces naeslundii, 7 strains were identified as Actinomyces oris and 1 strain were identified as Actinomyces sp. using Blastn. In this study, we showed that some oral Actinomyces species can grow on Streptococcus-selective MS agar plates. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Peripheral ischaemic retinopathy and neovascularisation in a patient with subacute streptococcus mitis-induced bacterial endocarditis.

    Science.gov (United States)

    Leysen, Laura S; Kreps, Elke O; De Schryver, Ilse; Hoornaert, Kristien P; Smith, Vanessa; De Zaeytijd, Julie

    2017-01-01

    Objective: To describe a patient with peripheral retinal ischaemia and neovascularisation who was diagnosed with streptococcus mitis-induced bacterial endocarditis. Methods: Retrospective analysis of case report. A 57-year-old man presented with a history of a rapidly progressive, bilateral, painless visual loss. He also suffered from pain in the neck and lower back and a weight loss of 10 kg. He underwent a full ophthalmologic work-up, laboratory investigations, and imaging of the spine. Results: BCVA was reduced to 20/40 in the right eye and 20/32 in the left eye. Fundoscopy showed rare intra-retinal haemorrhages including few Roth spots and cotton wool lesions. Fluorescein angiography demonstrated large areas of peripheral retinal ischaemia and neovascularisation. Imaging of the spine showed spondylodiscitis on several levels. Further imaging and blood cultures confirmed bacterial endocarditis of the mitral valve. Streptococcus mitis was subsequently identified as the causative organism. Conclusion: Peripheral retinal ischaemia and neovascularisation were previously unrecognised as a feature of infectious endocarditis. Therefore, their presence, apart from the classic Roth spots, should prompt the consideration of infectious endocarditis in the etiologic work-up.

  5. Peripheral ischaemic retinopathy and neovascularisation in a patient with subacute streptococcus mitis-induced bacterial endocarditis

    Directory of Open Access Journals (Sweden)

    Leysen, Laura S.

    2017-09-01

    Full Text Available Objective: To describe a patient with peripheral retinal ischaemia and neovascularisation who was diagnosed with streptococcus mitis-induced bacterial endocarditis. Methods: Retrospective analysis of case report. A 57-year-old man presented with a history of a rapidly progressive, bilateral, painless visual loss. He also suffered from pain in the neck and lower back and a weight loss of 10 kg. He underwent a full ophthalmologic work-up, laboratory investigations, and imaging of the spine.Results: BCVA was reduced to 20/40 in the right eye and 20/32 in the left eye. Fundoscopy showed rare intra-retinal haemorrhages including few Roth spots and cotton wool lesions. Fluorescein angiography demonstrated large areas of peripheral retinal ischaemia and neovascularisation. Imaging of the spine showed spondylodiscitis on several levels. Further imaging and blood cultures confirmed bacterial endocarditis of the mitral valve. Streptococcus mitis was subsequently identified as the causative organism. Conclusion: Peripheral retinal ischaemia and neovascularisation were previously unrecognised as a feature of infectious endocarditis. Therefore, their presence, apart from the classic Roth spots, should prompt the consideration of infectious endocarditis in the etiologic work-up.

  6. Impact of High-Level Daptomycin Resistance in the Streptococcus mitis Group on Virulence and Survivability during Daptomycin Treatment in Experimental Infective Endocarditis

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    Garcia-de-la-Maria, C.; Xiong, Y. Q.; Pericas, J. M.; Armero, Y.; Moreno, A.; Mishra, N. N.; Rybak, M. J.; Tran, T. T.; Arias, C. A.; Sullam, P. M.; Bayer, A. S.

    2017-01-01

    ABSTRACT Among the viridans group streptococci, the Streptococcus mitis group is the most common cause of infective endocarditis. These bacteria have a propensity to be β-lactam resistant, as well as to rapidly develop high-level and durable resistance to daptomycin (DAP). We compared a parental, daptomycin-susceptible (DAPs) S. mitis/S. oralis strain and its daptomycin-resistant (DAPr) variant in a model of experimental endocarditis in terms of (i) their relative fitness in multiple target organs in this model (vegetations, kidneys, spleen) when animals were challenged individually and in a coinfection strategy and (ii) their survivability during therapy with daptomycin-gentamicin (an in vitro combination synergistic against the parental strain). The DAPr variant was initially isolated from the cardiac vegetations of animals with experimental endocarditis caused by the parental DAPs strain following treatment with daptomycin. The parental strain and the DAPr variant were comparably virulent when animals were individually challenged. In contrast, in the coinfection model without daptomycin therapy, at both the 106- and 107-CFU/ml challenge inocula, the parental strain outcompeted the DAPr variant in all target organs, especially the kidneys and spleen. When the animals in the coinfection model of endocarditis were treated with DAP-gentamicin, the DAPs strain was completely eliminated, while the DAPr variant persisted in all target tissues. These data underscore that the acquisition of DAPr in S. mitis/S. oralis does come at an intrinsic fitness cost, although this resistance phenotype is completely protective against therapy with a potentially synergistic DAP regimen. PMID:28264848

  7. Collagen-binding proteins of Streptococcus mutans and related streptococci.

    Science.gov (United States)

    Avilés-Reyes, A; Miller, J H; Lemos, J A; Abranches, J

    2017-04-01

    The ability of Streptococcus mutans to interact with collagen through the expression of collagen-binding proteins (CBPs) bestows this oral pathogen with an alternative to the sucrose-dependent mechanism of colonization classically attributed to caries development. Based on the abundance and distribution of collagen throughout the human body, stringent adherence to this molecule grants S. mutans with the opportunity to establish infection at different host sites. Surface proteins, such as SpaP, WapA, Cnm and Cbm, have been shown to bind collagen in vitro, and it has been suggested that these molecules play a role in colonization of oral and extra-oral tissues. However, robust collagen binding is not achieved by all strains of S. mutans, particularly those that lack Cnm or Cbm. These observations merit careful dissection of the contribution from these different CBPs towards tissue colonization and virulence. In this review, we will discuss the current understanding of mechanisms used by S. mutans and related streptococci to colonize collagenous tissues, and the possible contribution of CBPs to infections in different sites of the host. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. The Collagen Binding Proteins of Streptococcus mutans and Related Streptococci

    Science.gov (United States)

    Avilés-Reyes, Alejandro; Miller, James H.; Lemos, José A.; Abranches, Jacqueline

    2016-01-01

    Summary The ability of Streptococcus mutans to interact with collagen through the expression of collagen-binding proteins (CBPs) bestows this oral pathogen with an alternative to the sucrose-dependent mechanism of colonization classically attributed to caries development. Based on the abundance and distribution of collagen throughout the human body, stringent adherence to this molecule grants S. mutans with the opportunity to establish infection at different host sites. Surface proteins, such as SpaP, WapA, Cnm and Cbm, have been shown to bind collagen in vitro, and it has been suggested that these molecules play a role in colonization of oral and extra-oral tissues. However, robust collagen binding is not achieved by all strains of S. mutans, particularly those that lack Cnm or Cbm. These observations merit careful dissection of the contribution from these different CBPs towards tissue colonization and virulence. In this review, we will discuss the current understanding of mechanisms utilized by S. mutans and related streptococci to colonize collagenous tissues, and the possible contribution of CBPs to infections in different sites of the host. PMID:26991416

  9. Population diversity and dynamics of Streptococcus mitis, Streptococcus oralis, and Streptococcus infantis in the upper respiratory tracts of adults, determined by a nonculture strategy

    DEFF Research Database (Denmark)

    Bek-Thomsen, Malene; Tettelin, H; Hance, I

    2008-01-01

    . A culture-independent method was used, based on cloning and sequencing of PCR amplicons of the housekeeping gene gdh, which shows remarkable, yet species-specific, genetic polymorphism. Samples were collected from all potential ecological niches in the oral cavity and pharynx of two adults on two occasions......We reinvestigated the clonal diversity and dynamics of Streptococcus mitis and two other abundant members of the commensal microbiota of the upper respiratory tract, Streptococcus oralis and Streptococcus infantis, to obtain information about the origin of frequently emerging clones in this habitat...... with loss and acquisition from contacts. These findings provide a platform for understanding the mechanisms that govern the balance within the complex microbiota at mucosal sites and between the microbiota and the mucosal immune system of the host....

  10. Streptococcus mitis/human gingival fibroblasts co-culture: the best natural association in answer to the 2-hydroxyethyl methacrylate release

    Science.gov (United States)

    Di Giulio, Mara; D'Ercole, Simonetta; Zara, Susi; Cataldi, Amelia; Cellini, Luigina

    2012-01-01

    One of the major components of dental polymerized resin-based restorative materials is 2-hydroxyethyl methacrylate (HEMA) and its release in monomeric form interferes with the oral cavity environment. This study aimed to evaluate HEMA monomeric effects on the co-culture of Streptococcus mitis and human gingival fibroblasts (HGFs). Streptococcus mitis DS12 and S. mitis ATCC 6249 were co-cultivated with HGF in the presence of HEMA (3 mM), for 48 and 72 h; the amount of sessile and planktonic cells, as well as the prokaryotic and eukaryotic cell viability were analyzed in treated and untreated samples. The treatment of S. mitis/HGFs with HEMA did not produce significant effects on the bacterial adhesion and induced an increase in planktonic S. mitis ATCC 6249 population after 48 and 72 h. HEMA increased significantly the planktonic S. mitis ATCC 6249 viability when co-cultured with HGFs, while a cytotoxic effect on HGFs, without bacteria, was recorded. An increase of bacterial aggregation on HGFs was also detected with HEMA. Data obtained in this study suggest that HEMA exhibits a toxic effect mainly on eukaryotic cells and this effect can be modulated by co-cultivation with the S. mitis cells which, in the presence of the monomer, enhance their aggregation rate on HGFs. PMID:22229269

  11. Population dynamics of Streptococcus mitis in its natural habitat

    DEFF Research Database (Denmark)

    Hohwy, J.; Reinholdt, Jesper; Kilian, Mogens

    2001-01-01

    showed that the ability to persist was not distributed at random in the S. mitis biovar 1 population. However, neither immunoglobulin A1 protease activity nor the ability to bind alpha-amylase from saliva was a preferential characteristic of persistent genotypes. In contrast to current concepts of climax...

  12. Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem

    NARCIS (Netherlands)

    Bogert, van den B.; Boekhorst, te J.; Herrmann, R.; Smid, E.J.; Zoetendal, E.G.; Kleerebezem, M.

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus

  13. The novel species Streptococcus tigurinus and its association with oral infection.

    Science.gov (United States)

    Zbinden, Andrea; Bostanci, Nagihan; Belibasakis, Georgios N

    2015-01-01

    Streptococcus tigurinus is a novel species of viridans streptococci, shown to cause severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. S. tigurinus belongs to the Streptococcus mitis group and is most closely related to Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae and Streptococcus infantis. The presence of S. tigurinus in the human oral cavity has been documented, including in patients with periodontal disease. This review addresses the available scientific knowledge on S. tigurinus and its association with closely related streptococci, and discusses its putative involvement in common oral infections. While there is as yet no strong evidence on the involvement of S. tigurinus with oral infections, its presence in the oral cavity and its association with endocarditis warrants special attention for a link between oral and systemic infection.

  14. SCM-positive Streptococcus canis are predominant among pet-associated group G streptococci.

    Science.gov (United States)

    Verkühlen, Gerd-Josef; Pägelow, Dennis; Valentin-Weigand, Peter; Fulde, Marcus

    2016-01-01

    Streptococcus (S.) canis is a neglected zoonotic pathogen with increasing impor- tance. Since knowledge about its distribution in pets in Germany is scant, we designed a study and tested 335 dogs and 71 cats for colonization by S. canis. S. canis was isolated from swabs taken from the perianal region by culture and subsequent identification was performed biochemically as well as by PCR. In total, 15.8% (53) of the canine and 8.5% (six) of the feline strains grown on Staphlyo- coccus/Streptococcus Selective Agar were tested positive for the Lancefield group G antigen. The vast majority of strains expressing the Lancefield Group G carbohy- drate (56 out of 59) were further identified as S. canis underlining their outstanding role among animal-associated Group G streptococci (GGS). Furthermore, 90.0% of the canine and 83.3% of the feline S. canis strains harbour the species-specific anti- phagocytic M protein homologue SCM, which has been described as an important virulence factor. In contrast, emm-genes typically encoded by human-specific GGS could not be detected in any of the S. canis isolates. Taken together, this study provides insights into the distribution of the neglected zoonotic pathogen S. canis in a population of pets in Germany. The presence of SCM in the vast majority of strains indicates their pathogenic potential.

  15. Evolution of Streptococcus pneumoniae and its close commensal relatives

    DEFF Research Database (Denmark)

    Kilian, Mogens; Poulsen, Knud; Blomqvist, Trinelise

    2008-01-01

    Streptococcus pneumoniae is a member of the Mitis group of streptococci which, according to 16S rRNA-sequence based phylogenetic reconstruction, includes 12 species. While other species of this group are considered prototypes of commensal bacteria, S. pneumoniae is among the most frequent microbial...

  16. Association of viridans group streptococci from pregnant women with bacterial vaginosis and upper genital tract infection.

    Science.gov (United States)

    Rabe, L K; Winterscheid, K K; Hillier, S L

    1988-06-01

    The prevalence and role of viridans group streptococci in the female genital tract have not been well described. In this study of 482 pregnant women, 147 (30%) were culture positive for viridans group streptococci. Of 392 women with predominant Lactobacillus morphotypes by Gram stain (normal), 110 (28%) were colonized with viridans group streptococci, compared with 37 (41%) of 90 women with bacterial vaginosis (BV) (P = 0.02). To determine whether any species were associated with BV, 177 consecutively isolated viridans group streptococci from the vagina were identified to the species level by using the Facklam scheme. The most frequently isolated species from the vagina was Streptococcus intermedius (13%), followed by Streptococcus acidominimus (6%), Streptococcus constellatus (5%), Streptococcus sanguis II (4%), Streptococcus mitis (2%), Streptococcus salivarius (2%), Streptococcus morbillorum (2%), Streptococcus sanguis I (1%), Streptococcus mutans (0.2%), and Streptococcus uberis (0.2%) with an average of 1.2 species per woman. The distribution of the species among women with BV compared with normal women was not significantly different, with the exception of two species which were associated with BV: S. acidominimus (18% versus 3%, P less than 0.001) and S. morbillorum (6% versus 0.7%, P = 0.005). Amniotic fluid and placenta cultures yielded 54 isolates: S. sanguis II (13 isolates), S. acidominimus (9 isolates), S. intermedius (10 isolates), S. constellatus (3 isolates), S. mitis (4 isolates), S. sanguis I (4 isolates), S. morbillorum (5 isolates), S. mutans (2 isolates), S. uberis (1 isolate), mannitol-positive S. intermedius (1 isolate), and 2 isolates which were not classified. The distribution of species isolated from the upper genital tract was not a reflection of the distribution in the lower genital tract. Dextran-producing species of viridans group streptococci may have a greater pathogenic potential in the placenta than the non

  17. Recolonization of mutans Streptococci after application of chlorhexidine gel.

    Science.gov (United States)

    Vale, Glauber Campos; Cury, Altair Antoninha Del Bel; Arthur, Rodrigo Alex; Cury, Jaime Aparecido; Tabchoury, Cínthia Pereira Machado

    2014-01-01

    Streptococcus mutans is specifically suppressed by intensive treatment with chlorhexidine gel, but the time for recolonization and the effect on other oral bacteria are not totally clear. In this study, recolonization of mutans streptococci was evaluated in nine healthy adult volunteers, who were highly colonized with this microorganism. Stimulated saliva was collected before (baseline) and at 1, 7, 14, 21 and 28 days after application of 1% chlorhexidine gel on volunteers' teeth for two consecutive days. On each day, the gel was applied using disposable trays for 3 x 5 min with intervals of 5 min between each application. Saliva was plated on blood agar to determine total microorganisms (TM); on mitis salivarius agar to determine total streptococci (TS) and on mitis salivarius agar plus bacitracin to determine mutans streptococci (MS). Chlorhexidine was capable of reducing the counts of MS and the proportion of MS with regard to total microorganisms (%MS/TM) (p0.05) after 14 days for MS and 21 days for %MS/TM. The counts of TM and TS and the proportion of MS to total streptococci did not differ statistically from baseline (p>0.05) after chlorhexidine treatment. The results suggest that the effect of chlorhexidine gel treatment on suppression of mutans streptococci is limited to less than a month in highly colonized individuals.

  18. Anti-adhesive and pro-apoptotic effects of 2-hydroxyethyl methacrylate on human gingival fibroblasts co-cultured with Streptococcus mitis strains

    Science.gov (United States)

    Zara, S; Di Giulio, M; D’Ercole, S; Cellini, L; Cataldi, A

    2011-01-01

    Aim To evaluate and observe the cellular reactions that occur during the interaction/integration between 2-hydroxyethyl methacrylate/host tissue/microbial environment, in a co-culture of human gingival fibroblasts (HGF) and Streptococcus mitis strains. Methodology Streptococcus mitis were cultured with strains in the presence of 3 mmol L−1 HEMA for 48 h and 72 h. Cytotoxicity was evaluated by the trypan blue dye exclusion test. Apoptosis was evaluated by TUNEL analysis. Adhesion was evaluated by immunofluorescence and western blot analyses. Quantitative analyses of the results were acquired by Qwin Plus 3.5 and QuantityOne I-D analysis software, respectively. The statistical significance of the results was evaluated using t-tests and linear regression tests. Results The trypan blue dye test revealed 47.3% and 46.5% of dead fibroblasts after 48 and 72 h HEMA treatment, respectively, while bacterial viability was not influenced by the presence of HEMA and fibroblasts. The expression of pro-collagen I, involved in fibroblast adhesion, in untreated samples ranged from 12.49% to 6.91% of the positive area after 48 and 72 h, respectively, dropping to below 2% of the positive area in the other experimental conditions. Unlike the trypan blue test, co-cultured samples treated with HEMA showed 20% and 25% versus 17% and 21% (after 48 and 72 h, respectively) of apoptotic cells. Conclusions The evidence for HEMA toxicity and anti-adhesive effects against eukaryotic cells was reduced in the presence of bacteria, suggesting that dental resins should be well polymerized to avoid the spread of toxic monomers within the mouth. PMID:21902700

  19. Investigation of presence of α haemolytic streptococci, enterococci and streptococci-like bacteria in different materials originating from pigs

    Directory of Open Access Journals (Sweden)

    Stanojković Aleksandar

    2011-01-01

    Full Text Available The aim of this investigation was to establish the presence and prevalence of streptococci, enterococci and streptococci-like bacteria in various materials originating from healthy, slaughtered and dead pigs belonging to different categories from several farms and slaughterhouses in the Republic of Serbia. The total number of investigated samples comprised 226 swabs of tonsils and noses from clinically healthy breeders, swabs of tonsils from piglets 5-20 days old, parts of nasopharyngeal tonsils from breeders slaughtered in a slaughterhouse, parts of nasopharyngeal tonsils from piglets slaughtered in a slaughterhouse, swabs of slaughtered pig carcasses from a slaughterhouse, swabs from knives for evisceration in a slaughterhouse, as well as swabs of lungs, abdominal cavity and organs from piglets which died suddenly. The standard microbiological methods were used for investigations of the presence of the listed microorganisms. Commercial biochemical tests were used for the identification of the isolated bacteria and specific sera for capsular antigenes were used for serological determination of the isolated S. suis strains. It was established that the great majority of the isolated strains belonged to the genus Streptococcus (36 (75%, and the minority of the strains belonged to the following genera: Enterococcus (6 (10.4%, Aerococcus (3 (6.2%, Lactococcus (2 (4.2% and Globicatella (2 (4.2%. The great majority of Streptococcus species belonged to S. suis. The presence of other á haemolytic streptococci was established in the swabs of nasopharyngeal tonsils: Streptococcus sanguinis (13.8%, Streptococcus salivarius (5.6%, Streptococcus mitis (5.6%, Streptococcus parasanguinis (2.7% and Streptococcus oralis (2.7%. Also, S. bovis was isolated in a smaller percentage (5.6%. The greatest number of isolated bacteria from the genus Enterococcus belonged to Enterococcus faecalis (80%, while the minority of isolated strains belonged to Enterococcus

  20. Evolution of Streptococcus pneumoniae and its close commensal relatives

    DEFF Research Database (Denmark)

    Kilian, Mogens; Poulsen, Knud; Blomqvist, Trinelise

    2008-01-01

    Streptococcus pneumoniae is a member of the Mitis group of streptococci which, according to 16S rRNA-sequence based phylogenetic reconstruction, includes 12 species. While other species of this group are considered prototypes of commensal bacteria, S. pneumoniae is among the most frequent microbial...... of unique genes and their origin support the model that the entire cluster of S. pneumoniae, S. pseudopneumoniae, and S. mitis lineages evolved from pneumococcus-like bacteria presumably pathogenic to the common immediate ancestor of hominoids. During their adaptation to a commensal life style, most...

  1. Comparative analysis of the biological and physical properties of Enterococcus faecalis bacteriophage vB_EfaS_GEC-EfS_3 and Streptococcus mitis bacteriophage vB_SmM_GEC-SmitisM_2.

    Science.gov (United States)

    Rigvava, Sophio; Tchgkonia, Irina; Jgenti, Darejan; Dvalidze, Teona; Carpino, James; Goderdzishvili, Marina

    2013-01-01

    Enterococcus faecalis and Streptococcus mitis are common commensal inhabitants of the human gastrointestinal and genitourinary tracts. However, both species can be opportunistic pathogens and cause disease in nosocomial settings. These infections can be difficult to treat because of the frequency of antibiotic resistance among these strains. Bacteriophages are often suggested as an alternative therapeutic agent against these infections. In this study, E. faecalis and S. mitis strains were isolated from female patients with urinary tract infections. Bacteriophages active against these strains were isolated from sewage water from the Mtkvari River. Two phages, designated vB_EfaS_GEC-EfS_3 (Syphoviridae) and vB_SmM_GEC-SmitisM_2 (Myoviridae), were specific for E. faecalis and S. mitis, respectively. Each phage's growth patterns and adsorption rates were quantified. Sensitivity to ultraviolet light and temperature was determined, as was host range and serology. The S. mitis bacteriophage was found to be more resistant to ultraviolet light and exposure to high temperatures than the E. faecalis bacteriophage, despite having a much greater rate of replication. While each phage was able to infect a broad range of strains of the same species as the host species from which they were isolated, they were unable to infect other host species tested.

  2. Consideraciones sobre elaislamiento en exudados vaginales de Streptococcus morbillorum

    Directory of Open Access Journals (Sweden)

    J.M. F. Egido

    1995-06-01

    Full Text Available De el estúdio de 195 exudados vaginales enviados por el Servicio de Ginecologia de este hospital, durante el período 1988-1990, hemos seleccionado aquellos en los que el cultivo fue positivo para estreptococos, 58 (30% de los cuales 26 (44.8% correspondia a Streptococcus morbillorum, 9 (15.5% a Gardnerella vaginalis, 5 (8.6% a Enterococcus faecalis-durans, y a Streptococcus agalactiae, 3 (5.1% a Streptococcus mitis y Streptococcus mitis, 2 (3-4% a Streptococcus bovis y Streptococcus cremoris y 1 (1.7% a Streptococcus salivarius, Streptococcus equinus y Strptococcus sanguis II respectivamente. En todos los casos se observo antecedentes de actuacción medico- quirurjica en el tracto genital, y en el 52.8% de los casos fuô concomitante con el diagnostico clinico-micologico de candidiasis vaginal. La ideittificaccion bacteriologica se realizo mediante el sistema API 20 STREP (sistema api bioMêríeux GmbH, Nütingen, Alemania dando un patron tipico ("excelente identificacción" para el Streptococcus morbillorum.We have tested 195 vaginal secretions sent by Gynecology Service of this hospital between the years 1988 - 1990. We achieved positive culture for streptococci in 58 (30% of these cultures, 26 (44.8% corresponding to Streptococcus morbillorum 9 (15.5%, to Gardnerella vaginalis 5 (8.6%, to Enterococcus faecalis-durans and to Streptococcus agalactiae, 3 (5.1 % to Streptococcus mitis and milleri 2 (3-4%, to Streptococcus bovis and cremoris, and 1 (1.7% to Streptococcus salivarius, equinus and sanguis II respectively. We previously found that 52.8% of these patients were positive for vaginal candidiasis. The bacteriological identification done by the API 20 STREP System (bioMerieux GmbH, Nútingen, Germanyprovides a typical pattern ("good identification" for the Streptococcus morbillorum.

  3. Chromosomal islands of Streptococcus pyogenes and related streptococci: molecular switches for survival and virulence.

    Science.gov (United States)

    Nguyen, Scott V; McShan, William M

    2014-01-01

    Streptococcus pyogenes is a significant pathogen of humans, annually causing over 700,000,000 infections and 500,000 deaths. Virulence in S. pyogenes is closely linked to mobile genetic elements like phages and chromosomal islands (CI). S. pyogenes phage-like chromosomal islands (SpyCI) confer a complex mutator phenotype on their host. SpyCI integrate into the 5' end of DNA mismatch repair (MMR) gene mutL, which also disrupts downstream operon genes lmrP, ruvA, and tag. During early logarithmic growth, SpyCI excise from the bacterial chromosome and replicate as episomes, relieving the mutator phenotype. As growth slows and the cells enter stationary phase, SpyCI reintegrate into the chromosome, again silencing the MMR operon. This system creates a unique growth-dependent and reversible mutator phenotype. Additional CI using the identical attachment site in mutL have been identified in related species, including Streptococcus dysgalactiae subsp. equisimilis, Streptococcus anginosus, Streptococcus intermedius, Streptococcus parauberis, and Streptococcus canis. These CI have small genomes, which range from 13 to 20 kB, conserved integrase and DNA replication genes, and no identifiable genes encoding capsid proteins. SpyCI may employ a helper phage for packaging and dissemination in a fashion similar to the Staphylococcus aureus pathogenicity islands (SaPI). Outside of the core replication and integration genes, SpyCI and related CI show considerable diversity with the presence of many indels that may contribute to the host cell phenotype or fitness. SpyCI are a subset of a larger family of streptococcal CI who potentially regulate the expression of other host genes. The biological and phylogenetic analysis of streptococcal chromosomal islands provides important clues as to how these chromosomal islands help S. pyogenes and other streptococcal species persist in human populations in spite of antibiotic therapy and immune challenges.

  4. Penicillin-resistant viridans streptococci have obtained altered penicillin-binding protein genes from penicillin-resistant strains of Streptococcus pneumoniae.

    OpenAIRE

    Dowson, C G; Hutchison, A; Woodford, N; Johnson, A P; George, R C; Spratt, B G

    1990-01-01

    Penicillin-resistant strains of Streptococcus pneumoniae possess altered forms of penicillin-binding proteins (PBPs) with decreased affinity for penicillin. The PBP2B genes of these strains have a mosaic structure, consisting of regions that are very similar to those in penicillin-sensitive strains, alternating with regions that are highly diverged. Penicillin-resistant strains of viridans groups streptococci (e.g., S. sanguis and S. oralis) that produce altered PBPs have also been reported. ...

  5. Comparative Genomics Analysis of Streptococcus Isolates from the Human Small Intestine Reveals their Adaptation to a Highly Dynamic Ecosystem

    Science.gov (United States)

    Van den Bogert, Bartholomeus; Boekhorst, Jos; Herrmann, Ruth; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

    2013-01-01

    The human small-intestinal microbiota is characterised by relatively large and dynamic Streptococcus populations. In this study, genome sequences of small-intestinal streptococci from S. mitis, S. bovis, and S. salivarius species-groups were determined and compared with those from 58 Streptococcus strains in public databases. The Streptococcus pangenome consists of 12,403 orthologous groups of which 574 are shared among all sequenced streptococci and are defined as the Streptococcus core genome. Genome mining of the small-intestinal streptococci focused on functions playing an important role in the interaction of these streptococci in the small-intestinal ecosystem, including natural competence and nutrient-transport and metabolism. Analysis of the small-intestinal Streptococcus genomes predicts a high capacity to synthesize amino acids and various vitamins as well as substantial divergence in their carbohydrate transport and metabolic capacities, which is in agreement with observed physiological differences between these Streptococcus strains. Gene-specific PCR-strategies enabled evaluation of conservation of Streptococcus populations in intestinal samples from different human individuals, revealing that the S. salivarius strains were frequently detected in the small-intestine microbiota, supporting the representative value of the genomes provided in this study. Finally, the Streptococcus genomes allow prediction of the effect of dietary substances on Streptococcus population dynamics in the human small-intestine. PMID:24386196

  6. Structures of two cell wall-associated polysaccharides of a Streptococcus mitis biovar 1 strain. A unique teichoic acid-like polysaccharide and the group O antigen which is a C-polysaccharide in common with pneumococci

    DEFF Research Database (Denmark)

    Bergström, N; Jansson, P.-E.; Kilian, Mogens

    2000-01-01

    The cell wall of Streptococcus mitis biovar 1 strain SK137 contains the C-polysaccharide known as the common antigen of a closely related species Streptococcus pneumoniae, and a teichoic acid-like polysaccharide with a unique structure. The two polysaccharides are different entities and could...... be partially separated by gel chromatography. The structures of the two polysaccharides were determined by chemical methods and by NMR spectroscopy. The teichoic acid-like polymer has a heptasaccharide phosphate repeating unit with the following structure: The structure neither contains ribitol nor glycerol...... phosphate as classical teichoic acids do, thus we have used the expression teichoic acid-like for this polysaccharide. The following structure of the C-polysaccharide repeating unit was established: where AAT is 2-acetamido-4-amino-2,4, 6-trideoxy-D-galactose. It has a carbohydrate backbone identical...

  7. Nutritionally Variant Streptococci Interfere with Streptococcus mutans Adhesion Properties and Biofilm Formation.

    Science.gov (United States)

    Angius, Fabrizio; Madeddu, Maria Antonietta; Pompei, Raffaello

    2015-04-01

    The bacterial species Streptococcus mutans is known as the main cause of dental caries in humans. Therefore, much effort has focused on preventing oral colonization by this strain or clearing it from oral tissues. The oral cavity is colonized by several bacterial species that constitute the commensal oral flora, but none of these is able to interfere with the cariogenic properties of S. mutans. This paper describes the interfering ability of some nutritionally variant streptococcal strains (NVS) with S. mutans adhesion to glass surfaces and also to hydroxylapatite. In mixed cultures, NVS induce a complete inhibition of S. mutans microcolony formation on cover glass slides. NVS can also block the adherence of radiolabeled S. mutans to hydroxylapatite in the presence of both saliva and sucrose. The analysis of the action mechanism of NVS demonstrated that NVS are more hydrophobic than S. mutans and adhere tightly to hard surfaces. In addition, a cell-free culture filtrate of NVS was also able to interfere with S. mutans adhesion to hydroxylapatite. Since NVS are known to secrete some important bacteriolytic enzymes, we conclude that NVS can be a natural antagonist to the cariogenic properties of S. mutans.

  8. Detection of Group B Streptococci in Lim Broth by Use of Group B Streptococcus Peptide Nucleic Acid Fluorescent In Situ Hybridization and Selective and Nonselective Agars▿

    Science.gov (United States)

    Montague, Naomi S.; Cleary, Timothy J.; Martinez, Octavio V.; Procop, Gary W.

    2008-01-01

    The sensitivity, specificity, and positive and negative predictive values for the detection of group B streptococci from Lim enrichment broth with sheep blood agar (SBA), with selective Streptococcus agar (SSA), and by a peptide nucleic acid fluorescent in situ hybridization (PNA FISH) assay were as follows: for culture on SBA, 68.4%, 100%, 100%, and 87.9%, respectively; for culture on SSA, 85.5%, 100%, 100%, and 94.1%, respectively; and for the PNA FISH assay, 97.4%, 98.3%, 96.1%, and 98.9%, respectively. PMID:18667597

  9. Detection of group B streptococci in Lim broth by use of group B streptococcus peptide nucleic acid fluorescent in situ hybridization and selective and nonselective agars.

    Science.gov (United States)

    Montague, Naomi S; Cleary, Timothy J; Martinez, Octavio V; Procop, Gary W

    2008-10-01

    The sensitivity, specificity, and positive and negative predictive values for the detection of group B streptococci from Lim enrichment broth with sheep blood agar (SBA), with selective Streptococcus agar (SSA), and by a peptide nucleic acid fluorescent in situ hybridization (PNA FISH) assay were as follows: for culture on SBA, 68.4%, 100%, 100%, and 87.9%, respectively; for culture on SSA, 85.5%, 100%, 100%, and 94.1%, respectively; and for the PNA FISH assay, 97.4%, 98.3%, 96.1%, and 98.9%, respectively.

  10. Identification of clinically relevant viridans streptococci by an oligonucleotide array.

    Science.gov (United States)

    Chen, Chao Chien; Teng, Lee Jene; Kaiung, Seng; Chang, Tsung Chain

    2005-04-01

    Viridans streptococci (VS) are common etiologic agents of subacute infective endocarditis and are capable of causing a variety of pyogenic infections. Many species of VS are difficult to differentiate by phenotypic traits. An oligonucleotide array based on 16S-23S rRNA gene intergenic spacer (ITS) sequences was developed to identify 11 clinically relevant VS. These 11 species were Streptococcus anginosus, S. constellatus, S. gordonii, S. intermedius, S. mitis, S. mutans, S. oralis, S. parasanguinis, S. salivarius, S. sanguinis, and S. uberis. The method consisted of PCR amplification of the ITS regions by using a pair of universal primers, followed by hybridization of the digoxigenin-labeled PCR products to a panel of species-specific oligonucleotides immobilized on a nylon membrane. After 120 strains of the 11 species of VG and 91 strains of other bacteria were tested, the sensitivity and specificity of the oligonucleotide array were found to be 100% (120 of 120 strains) and 95.6% (87 of 91 strains), respectively. S. pneumoniae cross-hybridized to the probes used for the identification of S. mitis, and simple biochemical tests such as optochin susceptibility or bile solubility should be used to differentiate S. pneumoniae from S. mitis. In conclusion, identification of species of VS by use of the present oligonucleotide array is accurate and could be used as an alternative reliable method for species identification of strains of VS.

  11. Queratopatía cristalina: diagnóstico clínico y microbiológico de una infección corneal infrecuente causada por el grupo Streptococcus mitis

    Directory of Open Access Journals (Sweden)

    Gustavo J Galperín

    2011-09-01

    Full Text Available El objetivo del presente informe es describir un caso de queratopatía cristalina causada por microorganismos pertenecientes al grupo Streptococcus mitis en una paciente que concurrió a la consulta oftalmológica por molestias en su ojo derecho. Al examen oftalmológico presentó un punto de sutura interrumpida de nylon 10-0 sin tensión y con secreciones mucosas adheridas. El punto flojo fue retirado bajo normas de asepsia. Se indicó colirio de moxifloxacina al 0,5 %; el ojo tuvo una evolución adecuada, con una correcta epitelización. Sin embargo, luego de 15 días desarrolló un infiltrado blanquecino arboriforme. Se tomó una muestra en el quirófano, enhebrando el trayecto intraestromal de la sutura retirada con sutura de vicryl 7-0. Se indicaron colirios de vancomicina con 50 mg/ml. El infiltrado se mantuvo estable durante 45 días, luego se incrementó el tamaño y se produjo necrosis tisular con peligro de perforación corneal. Se realizó un recubrimiento conjuntival bipediculado. La paciente evolucionó favorablemente y luego de la retracción espontánea del recubrimiento, se observó leucoma cicatrizal y neovasos corneales.Crystalline keratopathy: an infrequent corneal infection produced by the Streptococcus mitis group. The objective of this report is to describe a case of crystalline keratopathy caused by the Streptococcus mitis group corresponding to a patient who attended hospital for discomfort in his right eye. The ophthalmological examination showed an interrupted stitch of 10-0 nylon suture without tension and with attached mucus secretions. The loose suture was removed under aseptic conditions. Moxifloxacin 0.5 % eye drops were topically indicated. The treated eye successfully epithelialized and evolved favorably. However, after 15 days, a white tree-shaped infiltrate developed. A corneal sample was taken in the operating room, threading the intrastromal path of the removed stitch with a 7-0 vicryl suture. Vancomycin 50

  12. Garenoxacin treatment of experimental endocarditis caused by viridans group streptococci.

    Science.gov (United States)

    Anguita-Alonso, Paloma; Rouse, Mark S; Piper, Kerryl E; Steckelberg, James M; Patel, Robin

    2006-04-01

    The activity of garenoxacin was compared to that of levofloxacin or penicillin in a rabbit model of Streptococcus mitis group (penicillin MIC, 0.125 microg/ml) and Streptococcus sanguinis group (penicillin MIC, 0.25 microg/ml) endocarditis. Garenoxacin and levofloxacin had MICs of 0.125 and 0.5 microg/ml, respectively, for both study isolates. Rabbits with catheter-induced aortic valve endocarditis were given no treatment, penicillin at 1.2x10(6) IU/8 h intramuscularly, garenoxacin at 20 mg/kg of body weight/12 h intravenously, or levofloxacin at 40 mg/kg/12 h intravenously. For both isolates tested, garenoxacin area under the curve (AUC)/MIC and maximum concentration of drug in serum (Cmax)/MIC ratios were 368 and 91, respectively. Rabbits were sacrificed after 3 days of treatment; cardiac valve vegetations were aseptically removed and quantitatively cultured. For S. mitis group experimental endocarditis, all studied antimicrobial agents were more active than no treatment (PS. sanguinis group endocarditis, no studied antimicrobial agents were more active than no treatment. We conclude that AUC/MIC and Cmax/MIC ratios may not predict activity of some quinolones in experimental viridans group endocarditis and that garenoxacin and levofloxacin may not be ideal choices for serious infections caused by some quinolone-susceptible viridans group streptococci.

  13. Evolution and Diversity of the Antimicrobial Resistance Associated Mobilome in Streptococcus suis: A Probable Mobile Genetic Elements Reservoir for Other Streptococci.

    Science.gov (United States)

    Huang, Jinhu; Ma, Jiale; Shang, Kexin; Hu, Xiao; Liang, Yuan; Li, Daiwei; Wu, Zuowei; Dai, Lei; Chen, Li; Wang, Liping

    2016-01-01

    Streptococcus suis is a previously neglected, newly emerging multidrug-resistant zoonotic pathogen. Mobile genetic elements (MGEs) play a key role in intra- and interspecies horizontal transfer of antimicrobial resistance (AMR) determinants. Although, previous studies showed the presence of several MGEs, a comprehensive analysis of AMR-associated mobilome as well as their interaction and evolution has not been performed. In this study, we presented the AMR-associated mobilome and their insertion hotspots in S. suis . Integrative conjugative elements (ICEs), prophages and tandem MGEs were located at different insertion sites, while 86% of the AMR-associated MGEs were inserted at rplL and rum loci. Comprehensive analysis of insertions at rplL and rum loci among four pathogenic Streptococcus species ( Streptococcus agalactiae, Streptococcus pneumoniae, Streptococcus pyogenes , and S. suis ) revealed the existence of different groups of MGEs, including Tn5252, ICE Sp 1108, and TnGBS2 groups ICEs, Φm46.1 group prophage, ICE_ICE and ICE_prophage tandem MGEs. Comparative ICE genomics of ICE Sa 2603 family revealed that module exchange and acquisition/deletion were the main mechanisms in MGEs' expansion and evolution. Furthermore, the observation of tandem MGEs reflected a novel mechanism for MGE diversity. Moreover, an in vitro competition assay showed no visible fitness cost was observed between different MGE-carrying isolates and a conjugation assay revealed the transferability of ICE Sa 2603 family of ICEs. Our statistics further indicated that the prevalence and diversity of MGEs in S. suis is much greater than in other three species which prompted our hypothesis that S. suis is probably a MGEs reservoir for other streptococci. In conclusion, our results showed that acquisition of MGEs confers S. suis not only its capability as a multidrug resistance pathogen, but also represents a paradigm to study the modular evolution and matryoshkas of MGEs.

  14. Evolution and diversity of the antimicrobial resistance associated mobilome in Streptococcus suis: a probable mobile genetic elements reservoir for other streptococci

    Directory of Open Access Journals (Sweden)

    Jinhu Huang

    2016-10-01

    Full Text Available Streptococcus suis is a previously neglected, newly emerging multidrug-resistant zoonotic pathogen. Mobile genetic elements (MGEs play a key role in intra- and interspecies horizontal transfer of antimicrobial resistance (AMR determinants. Although previous studies showed the presence of several MGEs, a comprehensive analysis of AMR-associated mobilome as well as their interaction and evolution has not been performed. In this study, we presented the AMR-associated mobilome and their insertion hotspots in S. suis. Integrative conjugative elements (ICEs, prophages and tandem MGEs were located at different insertion sites, while 86% of the AMR-associated MGEs were inserted at rplL and rum loci. Comprehensive analysis of insertions at rplL and rum loci among four pathogenic Streptococcus species (Streptococcus agalactiae, Streptococcus pneumoniae, Streptococcus pyogenes, and S. suis revealed the existence of different groups of MGEs, including Tn5252, ICESp1108, and TnGBS2 groups ICEs, Φm46.1 group prophage, ICE_ICE and ICE_prophage tandem MGEs. Comparative ICE genomics of ICESa2603 family revealed that module exchange and acquisition/deletion were the main mechanisms in MGEs’ expansion and evolution. Furthermore, the observation of tandem MGEs reflected a novel mechanism for MGE diversity. Moreover, an in vitro competition assay showed no visible fitness cost was observed between different MGE-carrying isolates and a conjugation assay revealed the transferability of ICESa2603 family of ICEs. Our statistics further indicated that the prevalence and diversity of MGEs in S. suis is much greater than in other three species which prompted our hypothesis that S. suis is probably a MGEs reservoir for other streptococci. In conclusion, our results showed that acquisition of MGEs confers S. suis not only its capability as a multidrug resistance pathogen, but also represents a paradigm to study the modular evolution and matryoshkas of MGEs.

  15. Antimicrobial resistance in Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and group A beta-haemolytic streptococci in 2002-2003. Results of the multinational GRASP Surveillance Program

    DEFF Research Database (Denmark)

    Beekmann, Susan E; Heilmann, Kris P; Richter, Sandra S

    2005-01-01

    A multinational surveillance study, GRASP, was conducted between November 2002 and April 2003 with the aim of assessing rates of antimicrobial resistance among 2656 isolates of Streptococcus pneumoniae, 2486 isolates of group A beta-haemolytic streptococci, 1358 isolates of Haemophilus influenzae...... and 1047 of Moraxella catarrhalis from 20 countries in Europe, eastern Asia and southern Africa. Conspicuous differences between various countries were noted in the S. pneumoniae resistance rates observed for penicillin (0-79.2%) and erythromycin (4-66%), along with other antimicrobials. The percentage...... of MDR strains was above 25% in 8 of the 20 countries studied. Group A streptococcal macrolide resistance rates ranged from 0% to 35% by country, while rates of beta-lactamase production ranged from 0% to 39% for H. influenzae and 80-100% for M. catarrhalis. Antibiotic resistance in S. pneumoniae remains...

  16. Gene Regulation in Streptococcus pneumoniae: interplay between nutrition and virulence

    NARCIS (Netherlands)

    W.T. Hendriksen (Wouter)

    2010-01-01

    textabstractStreptococcus pneumoniae (the pneumococcus) is a Gram-positive bacterium, which belongs to the species of streptococci. Other pathogenic bacteria belonging to this class include Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus suis, Streptococcus uberis, Streptococcus

  17. Effectiveness of three different oral hygiene techniques on Viridans streptococci: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    N Naveen

    2016-01-01

    Full Text Available Introduction: Tongue cleaning is an important aspect of oral hygiene maintenance along with other mechanical and chemical aids. These methods have an influence on microorganism count in saliva. Aim: To assess the effectiveness of three different oral hygiene techniques on Viridans streptococci. Materials and Methods: This was a randomized controlled trial with 45 study subjects aged between 14 and 16 years and were randomly allocated into three groups: Group A - plastic tongue scraper, Group B - chlorhexidine mouthwash along with plastic tongue scraper, and Group C - chlorhexidine mouthwash. Unstimulated salivary samples were collected on the 1st, 7th, and 15th day before routine oral hygiene practices. Saliva samples were collected and incubated for 48 h on itis Salivarius(MS agar. Streptococcus mitis, Streptococcus mutans, and Streptococcus salivarius were counted. Data were analyzed using descriptive and inferential statistics. Results: The mean count of S. mitis, S. mutans, and S. salivarius for Group A, B, and C was found to be significant (P < 0.001 when compared between 1st, 7th, and 15th day. Between-groups comparisons revealed a significant difference between Groups A and C, B and C (P < 0.001. Conclusion: There was a significant reduction in bacterial count in all the participants indicating that all the three methods are useful in improving oral hygiene. Combination technique was found to be most effective.

  18. Strain-related acid production by oral streptococci

    DEFF Research Database (Denmark)

    de Soet, JJ; Nyvad, Bente; Kilian, Mogens

    2000-01-01

    Acid production, in particular at low pH, is thought to be an important ecological determinant in dental caries. The aim of the present study was to determine the acid producing capability at different pH levels of 47 streptococcal strains, representing 9 species, isolated from human dental plaque....... The bacteria were grown until mid log-phase under anaerobic conditions and acid production was measured in a pH-stat system at pH 7.0, 6.0, 5.5 and 5.0. At all pH values, the mean velocity of acid production (V(ap)) by Streptococcus mutans and S. sobrinus was significantly higher (p... that of the other oral streptococci, including S. mitis, S. oralis, S. gordonii, S. sanguis, S. intermedius, S. anginosus, S. constellatus, and S. vestibularis. However, the V(ap) of some strains of S. mitis biovar 1 and S. oralis, particularly at pH values of 7.0 and 6.0, exceeded that of some strains of S. mutans...

  19. Relationship between the ability of oral streptococci to interact with platelet glycoprotein Ibalpha and with the salivary low-molecular-weight mucin, MG2.

    Science.gov (United States)

    Plummer, Christopher; Douglas, Charles William Ian

    2006-12-01

    The oral streptococci Streptococcus sanguinis, Streptococcus gordonii and Streptococcus oralis are common aetiological agents of infective endocarditis, and their ability to adhere to and induce the aggregation of platelets is thought to be a virulence trait. The platelet glycoprotein GPIbalpha has been implicated as the adhesion receptor for S. sanguinis and S. gordonii, but it is not known if this is the case for S. oralis and other species. The aim of this study was to determine the GPIbalpha-interactive capability of a range of oral streptococci and to determine the relationship between this capability and their ability to interact with the salivary constituents that they would encounter in their normal habitat. All platelet-adhesive S. sanguinis strains and most S. gordonii strains adhered in a GPIbalpha-dependent manner, but strains of S. oralis, Streptococcus cristatus, Streptococcus parasanguinis and Streptococcus mitis had no direct affinity for platelets. Those strains that were able to bind GPIbalpha also bound to the low-molecular-weight submandibular salivary mucin, MG2, and this interaction was sialic acid-dependent. The data suggest that S. sanguinis and S. gordonii may be efficient colonizers of platelet vegetations because of their adaptation to recognize sialylated salivary mucins. In contrast, S. oralis does not interact with platelets and so is likely to colonize vegetations through an as yet unidentified mechanism.

  20. Effective oral health in infective endocarditis: efficacy of high-street mouthwashes against the viridans group streptococci.

    Science.gov (United States)

    Elshibly, Ahmed; Coulter, Wilson A; Millar, Beverley Cherie; Prendergast, Bernard D; Thornhill, Martin; Irwin, Christopher; Goldsmith, Colin E; Moore, John E

    2014-05-01

    Recent UK National Institute for Health and Clinical Excellence guidelines state that there is no longer a need for oral antibiotic prophylaxis in patients undergoing dental procedures who are at risk of infective endocarditis (IE), and advocate the importance of maintaining good oral health. As viridans group streptococci (VGS) are common etiological agents of IE and inhabitants of the mouth, the purpose of this study was to examine the efficacy of common high-street mouthwashes against four classes of VGS organisms (salivarius, mitis, anginosus, and mutans groupings). The survival of VGS, Streptococcus gordonii (National Collection of Type Cultures [NCTC] 7865), Streptococcus intermedius (NCTC 11324), Streptococcus mutans (NCTC 10449), Streptococcus oralis (NCTC 11427), Streptococcus pneumoniae (NCTC 7465, NCTC 7978, & American Type Culture Collection 49619) and Streptococcus salivarius (NCTC 8618) was assessed in vitro following treatment of approximately 10(7) c.f.u. in planktonic state with four mouthwashes. No organisms were culturable following 1-min exposure, and were not recovered following non-selective enrichment following incubation in Brain Heart Infusion broth supplemented with 0.8% (w/v) yeast extract. These data indicate that such mouthwashes are able to completely kill VGS organisms tested in planktonic solution, where their use would promote good oral hygiene in patients at risk of IE. © 2014 Wiley Publishing Asia Pty Ltd.

  1. Survey of strain distribution and antibiotic resistance pattern of group B streptococci (Streptococcus agalactiae isolated from clinical specimens

    Directory of Open Access Journals (Sweden)

    Mousavi, Seyed Masoud

    2016-09-01

    Full Text Available Aim: The aims of the present study were to determine the antibiotic susceptibility profils with particular emphasis on susceptible or resistant strains to macrolides and lincosamids antibiotics and to determine possible antibiotic resistance mechanisms occurring in group B streptococci (GBS strains using PCR assay and disk diffusion method.Methods: A total of 62 clinical GBS strains were investigated. Antibacterial susceptibility testing was performed using the disk diffusion method and inducible resistance test for clindamycin by standard double disk diffusion or D-zone test for all isolates to differentiate macrolide resistance phenotype (M, constitutive macrolide-lincosamide-streptogramin B phenotype (cMLS and induced macrolide-lincosamide-streptogramin B phenotype (iMLS. In addition, minimum inhibitory concentrations (MIC of penicillin were determined for all isolates. Finally, possible existence of antibiotic resistance genes for erythromycin , and and for clindamycin were examined among isolates using PCR assay.Results: All 62 isolates were susceptible to penicillin, ampicillin, linezolid, cefazoline and vancomycin. However, 93.5% (n=58 of isolates showed an increased MIC to penicillin. The overall rate of erythromycin resistance was 35.5% (n=22. All erythromycin-resistant isolates displayed the M phenotype (100%, n=22. All three erythromycin resistance genes (i.e. , and were found in erythromycin-resistant isolates.Conclusion: It was concluded that prescribing antibiotic without antibacterial susceptibility tests should be prevented because of the high prevalence of erythromycin-resistant GBS strains and the fact that erythromycin-resistant GBS strains has shown an increased MIC to penicillin, as the drug of choice for treating GBS infections.

  2. Characterization of a new CAMP factor carried by an integrative and conjugative element in Streptococcus agalactiae and spreading in Streptococci.

    Directory of Open Access Journals (Sweden)

    Sarah Chuzeville

    Full Text Available Genetic exchanges between Streptococci occur frequently and contribute to their genome diversification. Most of sequenced streptococcal genomes carry multiple mobile genetic elements including Integrative and Conjugative Elements (ICEs that play a major role in these horizontal gene transfers. In addition to genes involved in their mobility and regulation, ICEs also carry genes that can confer selective advantages to bacteria. Numerous elements have been described in S. agalactiae especially those integrated at the 3' end of a tRNA(Lys encoding gene. In strain 515 of S. agalactiae, an invasive neonate human pathogen, the ICE (called 515_tRNA(Lys is functional and carries different putative virulence genes including one encoding a putative new CAMP factor in addition to the one previously described. This work demonstrated the functionality of this CAMP factor (CAMP factor II in Lactococcus lactis but also in pathogenic strains of veterinary origin. The search for co-hemolytic factors in a collection of field strains revealed their presence in S. uberis, S. dysgalactiae, but also for the first time in S. equisimilis and S. bovis. Sequencing of these genes revealed the prevalence of a species-specific factor in S. uberis strains (Uberis factor and the presence of a CAMP factor II encoding gene in S. bovis and S. equisimilis. Furthermore, most of the CAMP factor II positive strains also carried an element integrated in the tRNA(Lys gene. This work thus describes a CAMP factor that is carried by a mobile genetic element and has spread to different streptococcal species.

  3. Phylogenomic and MALDI-TOF MS analysis of Streptococcus sinensis HKU4T reveals a distinct phylogenetic clade in the genus Streptococcus.

    Science.gov (United States)

    Teng, Jade L L; Huang, Yi; Tse, Herman; Chen, Jonathan H K; Tang, Ying; Lau, Susanna K P; Woo, Patrick C Y

    2014-10-20

    Streptococcus sinensis is a recently discovered human pathogen isolated from blood cultures of patients with infective endocarditis. Its phylogenetic position, as well as those of its closely related species, remains inconclusive when single genes were used for phylogenetic analysis. For example, S. sinensis branched out from members of the anginosus, mitis, and sanguinis groups in the 16S ribosomal RNA gene phylogenetic tree, but it was clustered with members of the anginosus and sanguinis groups when groEL gene sequences used for analysis. In this study, we sequenced the draft genome of S. sinensis and used a polyphasic approach, including concatenated genes, whole genomes, and matrix-assisted laser desorption ionization-time of flight mass spectrometry to analyze the phylogeny of S. sinensis. The size of the S. sinensis draft genome is 2.06 Mb, with GC content of 42.2%. Phylogenetic analysis using 50 concatenated genes or whole genomes revealed that S. sinensis formed a distinct cluster with Streptococcus oligofermentans and Streptococcus cristatus, and these three streptococci were clustered with the "sanguinis group." As for phylogenetic analysis using hierarchical cluster analysis of the mass spectra of streptococci, S. sinensis also formed a distinct cluster with S. oligofermentans and S. cristatus, but these three streptococci were clustered with the "mitis group." On the basis of the findings, we propose a novel group, named "sinensis group," to include S. sinensis, S. oligofermentans, and S. cristatus, in the Streptococcus genus. Our study also illustrates the power of phylogenomic analyses for resolving ambiguities in bacterial taxonomy. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Characterization of salivary alpha-amylase binding to Streptococcus sanguis

    International Nuclear Information System (INIS)

    Scannapieco, F.A.; Bergey, E.J.; Reddy, M.S.; Levine, M.J.

    1989-01-01

    The purpose of this study was to identify the major salivary components which interact with oral bacteria and to determine the mechanism(s) responsible for their binding to the bacterial surface. Strains of Streptococcus sanguis, Streptococcus mitis, Streptococcus mutans, and Actinomyces viscosus were incubated for 2 h in freshly collected human submandibular-sublingual saliva (HSMSL) or parotid saliva (HPS), and bound salivary components were eluted with 2% sodium dodecyl sulfate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western transfer, alpha-amylase was the prominent salivary component eluted from S. sanguis. Studies with 125 I-labeled HSMSL or 125 I-labeled HPS also demonstrated a component with an electrophoretic mobility identical to that of alpha-amylase which bound to S. sanguis. Purified alpha-amylase from human parotid saliva was radiolabeled and found to bind to strains of S. sanguis genotypes 1 and 3 and S. mitis genotype 2, but not to strains of other species of oral bacteria. Binding of [ 125 I]alpha-amylase to streptococci was saturable, calcium independent, and inhibitable by excess unlabeled alpha-amylases from a variety of sources, but not by secretory immunoglobulin A and the proline-rich glycoprotein from HPS. Reduced and alkylated alpha-amylase lost enzymatic and bacterial binding activities. Binding was inhibited by incubation with maltotriose, maltooligosaccharides, limit dextrins, and starch

  5. Use of phylogenetic and phenotypic analyses to identify nonhemolytic streptococci isolated from bacteremic patients.

    Science.gov (United States)

    Hoshino, Tomonori; Fujiwara, Taku; Kilian, Mogens

    2005-12-01

    The aim of this study was to evaluate molecular and phenotypic methods for the identification of nonhemolytic streptococci. A collection of 148 strains consisting of 115 clinical isolates from cases of infective endocarditis, septicemia, and meningitis and 33 reference strains, including type strains of all relevant Streptococcus species, were examined. Identification was performed by phylogenetic analysis of nucleotide sequences of four housekeeping genes, ddl, gdh, rpoB, and sodA; by PCR analysis of the glucosyltransferase (gtf) gene; and by conventional phenotypic characterization and identification using two commercial kits, Rapid ID 32 STREP and STREPTOGRAM and the associated databases. A phylogenetic tree based on concatenated sequences of the four housekeeping genes allowed unequivocal differentiation of recognized species and was used as the reference. Analysis of single gene sequences revealed deviation clustering in eight strains (5.4%) due to homologous recombination with other species. This was particularly evident in S. sanguinis and in members of the anginosus group of streptococci. The rate of correct identification of the strains by both commercial identification kits was below 50% but varied significantly between species. The most significant problems were observed with S. mitis and S. oralis and 11 Streptococcus species described since 1991. Our data indicate that identification based on multilocus sequence analysis is optimal. As a more practical alternative we recommend identification based on sodA sequences with reference to a comprehensive set of sequences that is available for downloading from our server. An analysis of the species distribution of 107 nonhemolytic streptococci from bacteremic patients showed a predominance of S. oralis and S. anginosus with various underlying infections.

  6. Antibiotic modulation of the plasminogen binding ability of viridans group streptococci.

    Science.gov (United States)

    Teles, Cristina; Smith, Andrew; Lang, Sue

    2012-01-01

    The ability of viridans group streptococci to bind human plasminogen and its subsequent activation into plasmin may contribute to the pathogenesis of infective endocarditis (IE) by leading to a decreased stability of the streptococcal vegetation and facilitating dehiscence of emboli. At levels greater than or equal to their MICs, penicillin, vancomycin, and linezolid are efficacious in the treatment of streptococcal endocarditis. However, at sub-MICs, antibiotics can modulate the expression of bacterial genes, including virulence-associated genes, which can have counterproductive effects on the treatment of endocarditis. The effects of 1/8× and 1/4× MICs of penicillin, vancomycin, and linezolid on the plasminogen binding ability of IE isolates Streptococcus mitis 881/956, Streptococcus oralis 12601, and Streptococcus sanguinis 12403 were assessed phenotypically and the expression of plasminogen receptors α-enolase and glyceraldehyde 3-phosphate dehydrogenase of S. oralis 12601 when exposed to 1/4× MIC of penicillin, was analyzed through quantitative reverse transcription (qRT)-PCR. The plasminogen binding ability of S. mitis 881/956 and S. sanguinis 12403 remained unaffected by exposure to sub-MICs of all of the antibiotics tested, while that of S. oralis 12601 was significantly enhanced by all of the antibiotics tested at sub-MICs. qRT-PCR analysis of S. oralis 12601 demonstrated an upregulation of the eno and gapdh genes, indicating an overexpression of plasminogen receptors. These findings suggest that for some endocarditis isolates, the effect of antibiotic sub-MICs, in addition to a reduced antibacterial effect, may influence the clinical response to nonsurgical therapy. It remains difficult to accurately predict isolate responses to sub-MIC antimicrobials since there appears to be interspecies variation.

  7. Streptococcus oligofermentans inhibits Streptococcus mutans in biofilms at both neutral pH and cariogenic conditions

    NARCIS (Netherlands)

    Bao, X.; de Soet, J.J.; Tong, H.; Gao, X.; He, L.; van Loveren, C.; Deng, D.M.

    2015-01-01

    Homeostasis of oral microbiota can be maintained through microbial interactions. Previous studies showed that Streptococcus oligofermentans, a non-mutans streptococci frequently isolated from caries-free subjects, inhibited the cariogenic Streptococcus mutans by the production of hydrogen peroxide

  8. Penambahan xylitol dalam glukosa, sukrosa terhadap pertumbuhan Streptococcus mutans (in vitro (The Additional xylitol in glucose and sucrose on growth of Mutans Streptococci (in vitro

    Directory of Open Access Journals (Sweden)

    Susilowati Susilowati

    2014-12-01

    Full Text Available Background: Xylitol is a sugar alcohol group consisting of five-carbon chain and the sugar substitutes are recommended to prevent caries. Dietary sugars known as a good substrate for the growth of Streptococcus mutans (S. mutans. Two types of sugar, xylitol and dietary sugars have different effects on the growth of S.mutans. Purpose: The objective of this study were to determine the minimal inhibitory concentration (MIC of xylitol on the growth of S.mutans and to determine the addition of xylitol in glucose and sucrose in the growth of S. mutans in vitro. Methods: The samples were divided into 3 groups: xylitol group, xylitol and sucrose combination group, and xylitol and glucose combination group . In all groups were tested against S.mutans growth in various concentrations. Results: The minimum inhibitory concentration against S.mutans xylitol was equal to 0.625%. The addition of xylitol in sucrose the inhibition of S.mutans growth occurred at concentrations of 0.625 % and 2.5%. The addition of xylitol in glucose inhibited the growth of S.mutans at all concentrations. Conclusion: This study showed that the combination of xylitol with dietary sugars could inhibit the growth of S.mutans.Latar belakang: Xylitol adalah golongan gula alkohol yang terdiri dari lima rantai karbon dan merupakan sugar substitutes yang dianjurkan untuk mencegah terjadinya karies. Dietary sugars diketahui sebagai substrat yang baik untuk pertumbuhan bakteri rongga mulut salah satunya Streptococcus mutans (S. mutans. Dua jenis gula yaitu xylitol dan dietary sugars memiliki pengaruh yang berbeda pada pertumbuhan S. mutans. Tujuan: Tujuan dari penelitian ini adalah meneliti konsentrasi hambat minimal (Minimal Inhibitory Concentration/ MIC xylitol terhadap pertumbuhan S mutans dan meneliti pengaruh penambahan xylitol dalam glukosa dan dalam sukrosa terhadap pertumbuhan S. mutans secara in vitro. Metode: Sampel dibagi dalam 3 kelompok: kelompok xylitol, kelompok kombinasi

  9. MALDI-TOF mass spectrometry for differentiation between Streptococcus pneumoniae and Streptococcus pseudopneumoniae.

    Science.gov (United States)

    van Prehn, Joffrey; van Veen, Suzanne Q; Schelfaut, Jacqueline J G; Wessels, Els

    2016-05-01

    We compared the Vitek MS and Microflex MALDI-TOF mass spectrometry platform for species differentiation within the Streptococcus mitis group with PCR assays targeted at lytA, Spn9802, and recA as reference standard. The Vitek MS correctly identified 10/11 Streptococcus pneumoniae, 13/13 Streptococcus pseudopneumoniae, and 12/13 S. mitis/oralis. The Microflex correctly identified 9/11 S. pneumoniae, 0/13 S. pseudopneumoniae, and 13/13 S. mitis/oralis. MALDI-TOF is a powerful tool for species determination within the mitis group. Diagnostic accuracy varies depending on platform and database used. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  10. The influence of biosurfactants released by S-mitis BMS on the adhesion of pioneer strains and cariogenic bacteria

    NARCIS (Netherlands)

    Van Hoogmoed, CG; Van der Mei, HC; Busscher, HJ

    2004-01-01

    The influence of Streptococcus mitis BMS biosurfactants on the adhesion of eight pioneer and four cariogenic oral bacterial strains was, for a first screening, examined in a microtiter plate assay. The adhesion to pellicle-coated wells of three cariogenic strains was inhibited >70% by the

  11. [Evaluation of Prolex for the rapid identification of streptococci isolated in medical microbiology].

    Science.gov (United States)

    Loubinoux, J; Mihaila-Amrouche, L; Bouvet, A

    2004-10-01

    The need to rapidly identify streptococci responsible for acute infectious diseases has led to the development of agglutination techniques that are able to identify streptococcal group antigens (A, B, C, D, F, and G) directly from primoculture colonies on blood agar. The Prolex agglutination tests (Pro-Lab Diagnostics, Richmond Hill, Ontario, Canada), distributed in France by i2a, have been used for the determination of group antigens of 166 isolates of streptococci and enterococci previously identified in the National Reference Center for Streptococci. The results obtained with the Prolex reagents have permitted to correctly identify all pyogenic beta-hemolytic streptococci (23 Streptococcus pyogenes, 21 Streptococcus agalactiae, 33 Streptococcus dysgalactiae subsp. equisimilis including 6 group C and 27 group G, and 5 Streptococcus porcinus including 4 group B). Four differences between unexpected agglutinations (A or F) and species identifications have been obtained. These differences were observed for four non-hemolytic isolates of Streptococcus mutans, Streptococcus gordonii, Streptococcus infantarius, and Streptococcus suis. The anti-D reagent has been of value as a marker for isolates of enterococci. Thus, these results confirm the abilities of these agglutination tests for the grouping of beta-hemolytic streptococci. Moreover, the use of Prolex has the advantage to be rapid because of the non-enzymatic but chemical extraction of streptococcal antigens.

  12. Multiple alcohol dehydrogenases but no functional acetaldehyde dehydrogenase causing excessive acetaldehyde production from ethanol by oral streptococci.

    Science.gov (United States)

    Pavlova, Sylvia I; Jin, Ling; Gasparovich, Stephen R; Tao, Lin

    2013-07-01

    Ethanol consumption and poor oral hygiene are risk factors for oral and oesophageal cancers. Although oral streptococci have been found to produce excessive acetaldehyde from ethanol, little is known about the mechanism by which this carcinogen is produced. By screening 52 strains of diverse oral streptococcal species, we identified Streptococcus gordonii V2016 that produced the most acetaldehyde from ethanol. We then constructed gene deletion mutants in this strain and analysed them for alcohol and acetaldehyde dehydrogenases by zymograms. The results showed that S. gordonii V2016 expressed three primary alcohol dehydrogenases, AdhA, AdhB and AdhE, which all oxidize ethanol to acetaldehyde, but their preferred substrates were 1-propanol, 1-butanol and ethanol, respectively. Two additional dehydrogenases, S-AdhA and TdhA, were identified with specificities to the secondary alcohol 2-propanol and threonine, respectively, but not to ethanol. S. gordonii V2016 did not show a detectable acetaldehyde dehydrogenase even though its adhE gene encodes a putative bifunctional acetaldehyde/alcohol dehydrogenase. Mutants with adhE deletion showed greater tolerance to ethanol in comparison with the wild-type and mutant with adhA or adhB deletion, indicating that AdhE is the major alcohol dehydrogenase in S. gordonii. Analysis of 19 additional strains of S. gordonii, S. mitis, S. oralis, S. salivarius and S. sanguinis showed expressions of up to three alcohol dehydrogenases, but none showed detectable acetaldehyde dehydrogenase, except one strain that showed a novel ALDH. Therefore, expression of multiple alcohol dehydrogenases but no functional acetaldehyde dehydrogenase may contribute to excessive production of acetaldehyde from ethanol by certain oral streptococci.

  13. Identification of species of viridans group streptococci in clinical blood culture isolates by sequence analysis of the RNase P RNA gene, rnpB.

    Science.gov (United States)

    Westling, Katarina; Julander, Inger; Ljungman, Per; Vondracek, Martin; Wretlind, Bengt; Jalal, Shah

    2008-03-01

    Viridans group streptococci (VGS) cause severe diseases such as infective endocarditis and septicaemia. Genetically, VGS species are very close to each other and it is difficult to identify them to species level with conventional methods. The aims of the present study were to use sequence analysis of the RNase P RNA gene (rnpB) to identify VGS species in clinical blood culture isolates, and to compare the results with the API 20 Strep system that is based on phenotypical characteristics. Strains from patients with septicaemia or endocarditis were analysed with PCR amplification and sequence analysis of the rnpB gene. Clinical data were registered as well. One hundred and thirty two VGS clinical blood culture isolates from patients with septicaemia (n=95) or infective endocarditis (n=36) were analysed; all but one were identified by rnpB. Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii strains were most common in the patients with infective endocarditis. In the isolates from patients with haematological diseases, Streptococcus mitis and S. oralis dominated. In addition in 76 of the isolates it was possible to compare the results from rnpB analysis and the API 20 Strep system. In 39/76 (51%) of the isolates the results were concordant to species level; in 55 isolates there were no results from API 20 Strep. Sequence analysis of the RNase P RNA gene (rnpB) showed that almost all isolates could be identified. This could be of importance for evaluation of the portal of entry in patients with septicaemia or infective endocarditis.

  14. Distribution, Regulation and Role of the Agmatine Deiminase System in Mutans Streptococci

    OpenAIRE

    Griswold, Ann R.; Nascimento, Marcelle M.; Burne, Robert A.

    2009-01-01

    The agmatine deiminase system was identified in seven strains of mutans streptococci. Genes encoding the AgDS of Streptococcus rattus FA-1 were sequenced and found to share homology with the agu genes of Streptococcus mutans UA159. Agmatine inhibited bacterial growth, suggesting that the AgDS degrades a deleterious substance into useful compounds.

  15. Comparing the cariogenic species Streptococcus sobrinus and S. mutans on whole genome level

    NARCIS (Netherlands)

    Conrads, G.; de Soet, J.J.; Song, L.; Henne, K.; Sztajer, H.; Wagner-Döbler, I.; Zeng, A.P.

    2014-01-01

    Background: Two closely related species of mutans streptococci, namely Streptococcus mutans and Streptococcus sobrinus, are associated with dental caries in humans. Their acidogenic and aciduric capacity is directly associated with the cariogenic potential of these bacteria. To survive acidic and

  16. Comparative Genomics of the Bacterial Genus Streptococcus Illuminates Evolutionary Implications of Species Groups

    Science.gov (United States)

    Gao, Xiao-Yang; Zhi, Xiao-Yang; Li, Hong-Wei; Klenk, Hans-Peter; Li, Wen-Jun

    2014-01-01

    Members of the genus Streptococcus within the phylum Firmicutes are among the most diverse and significant zoonotic pathogens. This genus has gone through considerable taxonomic revision due to increasing improvements of chemotaxonomic approaches, DNA hybridization and 16S rRNA gene sequencing. It is proposed to place the majority of streptococci into “species groups”. However, the evolutionary implications of species groups are not clear presently. We use comparative genomic approaches to yield a better understanding of the evolution of Streptococcus through genome dynamics, population structure, phylogenies and virulence factor distribution of species groups. Genome dynamics analyses indicate that the pan-genome size increases with the addition of newly sequenced strains, while the core genome size decreases with sequential addition at the genus level and species group level. Population structure analysis reveals two distinct lineages, one including Pyogenic, Bovis, Mutans and Salivarius groups, and the other including Mitis, Anginosus and Unknown groups. Phylogenetic dendrograms show that species within the same species group cluster together, and infer two main clades in accordance with population structure analysis. Distribution of streptococcal virulence factors has no obvious patterns among the species groups; however, the evolution of some common virulence factors is congruous with the evolution of species groups, according to phylogenetic inference. We suggest that the proposed streptococcal species groups are reasonable from the viewpoints of comparative genomics; evolution of the genus is congruent with the individual evolutionary trajectories of different species groups. PMID:24977706

  17. luxS/AI-2密度感应对缓症链球菌生物膜致病力的影响%Biofilm formation and antimicrobial susceptibility of Streptococcus mitis in response to luxS/AI-2 signaling

    Institute of Scientific and Technical Information of China (English)

    陆笑; 翁春辉; 王劲茗; 刘少娟; 刘芹; 林珊

    2017-01-01

    Objective This paper aims to study the influence of luxS gene mutation of Streptococcus mitis on biofilm formation and antimicrobial susceptibility.Methods Culture in blood plate,Gram stain and susceptibility tests,and physiological and biochemical tests were first carried out.16S ribosomal DNA(rDNA) sequence homology analysis of clinical isolate was examined subsequently.The autoinducer-2(AI-2) bioluminescence assay of Vibrio harveyi BB 170 strain,multidrug resistance,and ability of biofilm formation were examined in luxS mutant and clinical isolate.The structure,exopolysaccharides,and dead/live cells of biofilm were scanned by confocal laser scanning microscope.Compared with one another,luxS mutant growth recruited by isolate supernatant or 4,5-dihydroxy-2,3-pentanedione(DPD) was experimented.Results luxS gene deletion decreased biofilm formation(P<0.001),loosened structure,and changed antimicrobial susceptibility(to ampiciliin,ciprofloxacin,tetracycline).However,isolate supernatant or DPD can recover the structure and ability of biofilm formation in luxS mutant.Conclusion luxS/AI-2 signaling can influence biofilm formation and antimicrobial susceptibility ofS.mitis with multidrug resistance.%目的 了解luxS基因敲除,自体诱导物-2(AI-2)密度感应信号缺失对缓症链球菌生物膜致病力表型的影响.方法 常规细菌培养、药敏试验、形态学与生化反应鉴定,16S核糖体DNA(rDNA)序列同源性分析,获得耐药性缓症链球菌临床分离株.同源重组法敲除luxS基因,构建突变株.哈氏弧菌BB170菌株生物发光实验检测AI-2信号;定量分析临床分离株与突变株生物膜形成量与抗菌药敏感性的差异;荧光黄染液、18909荧光增白染液、L7012死/活菌染液染色,激光共聚焦显微镜扫描,了解生物膜结构、胞外多糖、死/活菌分布差异;临床分离株上清液、4,5-二羟基-2,3-戊二酮(DPD)补偿生长实验确认突变株表型改变的原因.实验数

  18. Complete structure of the cell surface polysaccharide of Streptococcus oralis ATCC 10557: A receptor for lectin-mediated interbacterial adherence

    International Nuclear Information System (INIS)

    Abeygunawardana, C.; Bush, C.A.; Cisar, J.O.

    1991-01-01

    Lectin-carbohydrate binding is known to play an important role in a number of different cell-cell interactions including those between certain species of oral streptococci and actinomyces that colonize teeth. The cell wall polysaccharides of Streptococcus oralis ATCC 10557, S. oralis 34, and Streptococcus mitis J22, although not identical antigenically, each function as a receptor molecule for the galactose and N-acetylgalactosamine reactive fimbrial lectins of Actinomyces viscosus and Actinomyces naeslundii. Carbohydrate analysis of the receptor polysaccharide isolated from S. oralis ATCC 10557 shows galactose (3 mol), glucose (1 mol), GalNAc (1 mol), and rhamnose (1 mol). 1 H NMR spectra of the polysaccharide show that is partially O-acetylated. Analysis of the 1 H NMR spectrum of the de-O-acetylated polysaccharide shows that it is composed of repeating subunits containing six monosaccharides and that the subunits are joined by a phosphodiester linkage. The 1 H and 13 C NMR spectra were completely assigned by two-dimensional homonuclear correlation methods and by 1 H-detected heteronuclear multiple-quantum correlation ( 1 H[ 13 C]HMQC). The complete 1 H and 13 C assignment of the native polysaccharide was carried out by the same techniques augmented by a 13 C-coupled hybrid HMQC-COSY method, which is shown to be especially useful for carbohydrates in which strong coupling and overlapping peaks in the 1 H spectrum pose difficulties

  19. Chicken IgY Fc expressed by Eimeria mitis enhances the immunogenicity of E. mitis.

    Science.gov (United States)

    Qin, Mei; Tang, Xinming; Yin, Guangwen; Liu, Xianyong; Suo, Jingxia; Tao, Geru; Ei-Ashram, Saeed; Li, Yuan; Suo, Xun

    2016-03-21

    Eimeria species are obligate intracellular apicomplexan parasites, causing great economic losses in the poultry industry. Currently wild-and attenuated- type anticoccidial vaccines are used to control coccidiosis. However, their use in fast growing broilers is limited by vaccination side effects caused by medium and/or low immunogenic Eimeria spp. There is, therefore, a need for a vaccine with high immunogenicity for broilers. The avian yolk sac IgY Fc is the avian counterpart of the mammalian IgG Fc, which enhances immunogenicity of Fc-fusion proteins. Here, we developed a stable transgenic Eimeria mitis expressing IgY Fc (Emi.chFc) and investigated whether the avian IgY Fc fragment enhances the immunogenicity of E. mitis. Two-week-old broilers were immunized with either Emi.chFc or wild type Eimeria and challenged with wild type E. mitis to analyze the protective properties of transgenic Emi.chFc. Chickens immunized with Emi.chFc had significantly lower oocyst output, in comparison with PBS, mock control (transgenic E. mitis expressing HA1 from H9N2 avian influenza virus) and wildtype E. mitis immunized groups after challenge, indicating that IgY Fc enhanced the immunogenicity of E. mitis. Our findings suggest that IgY Fc-expressing Eimeria may be a better coccidiosis vaccine, and transgenic Eimeria expressing Fc-fused exogenous antigens may be used as a novel vaccine-delivery vehicle against a wide variety of pathogens.

  20. Exposición a Estreptococo del grupo B en mujeres mexicanas en edad reproductiva Serologic evidence of high exposure to Group B streptococci (Streptococcus agalactiae in Mexican women of reproductive age

    Directory of Open Access Journals (Sweden)

    Gerardo Palacios-Saucedo

    2002-01-01

    Full Text Available Objetivo. Evaluar la seroprevalencia de la infección por Estreptococo del grupo B (EGB en una muestra representativa de mujeres en edad reproductiva de la República Mexicana. Material y métodos. Se estudió una muestra representativa de sueros de la población femenina mexicana de 15 a 40 años de edad, de todos los niveles socioeconómicos. La muestra fue seleccionada del Banco Nacional de Sueros por muestreo aleatorio simple por computadora. Los sueros se obtuvieron durante la última encuesta seroepidemiológica nacional realizada en 1987 y 1988. Los ensayos para la estandarización y la evaluación de la seroprevalencia se llevaron a cabo en el Hospital de Pediatría del Centro Médico Nacional Siglo XXI, del Instituto Mexicano del Seguro Social (IMSS entre enero y noviembre de 1995. Se midieron anticuerpos IgG antipolisacárido de grupo de EGB usando un ensayo inmunoenzimático (ELISA estandarizado y validado en el laboratorio, utilizando un antígeno específico de grupo, producido y purificado a partir de la cepa de referencia de EGB 110. Resultados. Se estudió un total de 2 669 muestras de suero, de las cuales 2 405 fueron positivas para la presencia de anticuerpos IgG contra el antígeno de grupo de EGB. Esto corresponde a una seroprevalencia de 90.2 %. No hubo diferencia en los porcentajes de seropositividad por grupos de edad ni por entidades federativas. Conclusiones. Se detectó una elevada prevalencia de anticuerpos contra el antígeno de grupo del EGB. Los resultados de este estudio sugieren que existe una elevada exposición de las mujeres mexicanas jóvenes a este microrganismo.Objective. To assess the prevalence of IgG antibodies against Group B streptococci (GBS among women of reproductive age in Mexico. Material and Methods. Serum specimens were drawn from 15 to 40 year-old women, representative of all regions and socioeconomic levels of the country. The sample was randomly selected from Banco Nacional de Sueros (National

  1. Consideraciones sobre elaislamiento en exudados vaginales de Streptococcus morbillorum

    Directory of Open Access Journals (Sweden)

    J.M. F. Egido

    1995-06-01

    Full Text Available De el estúdio de 195 exudados vaginales enviados por el Servicio de Ginecologia de este hospital, durante el período 1988-1990, hemos seleccionado aquellos en los que el cultivo fue positivo para estreptococos, 58 (30% de los cuales 26 (44.8% correspondia a Streptococcus morbillorum, 9 (15.5% a Gardnerella vaginalis, 5 (8.6% a Enterococcus faecalis-durans, y a Streptococcus agalactiae, 3 (5.1% a Streptococcus mitis y Streptococcus mitis, 2 (3-4% a Streptococcus bovis y Streptococcus cremoris y 1 (1.7% a Streptococcus salivarius, Streptococcus equinus y Strptococcus sanguis II respectivamente. En todos los casos se observo antecedentes de actuacción medico- quirurjica en el tracto genital, y en el 52.8% de los casos fuô concomitante con el diagnostico clinico-micologico de candidiasis vaginal. La ideittificaccion bacteriologica se realizo mediante el sistema API 20 STREP (sistema api bioMêríeux GmbH, Nütingen, Alemania dando un patron tipico ("excelente identificacción" para el Streptococcus morbillorum.

  2. Streptococcus sanguinis induces neutrophil cell death by production of hydrogen peroxide.

    Science.gov (United States)

    Sumioka, Ryuichi; Nakata, Masanobu; Okahashi, Nobuo; Li, Yixuan; Wada, Satoshi; Yamaguchi, Masaya; Sumitomo, Tomoko; Hayashi, Mikako; Kawabata, Shigetada

    2017-01-01

    Streptococcus is the dominant bacterial genus in the human oral cavity and a leading cause of infective endocarditis. Streptococcus sanguinis belongs to the mitis group of streptococci and produces hydrogen peroxide (H2O2) by the action of SpxB, a pyruvate oxidase. In this study, we investigated the involvement of SpxB in survival of S. sanguinis in human blood and whether bacterial H2O2 exhibits cytotoxicity against human neutrophils. Results of a bactericidal test with human whole blood revealed that the spxB mutation in S. sanguinis is detrimental to its survival in blood. When S. sanguinis strains were exposed to isolated neutrophils, the bacterial survival rate was significantly decreased by spxB deletion. Furthermore, human neutrophils exposed to the S. sanguinis wild-type strain, in contrast to those exposed to an spxB mutant strain, underwent cell death with chromatin de-condensation and release of web-like extracellular DNA, reflecting induction of neutrophil extracellular traps (NETs). Since reactive oxygen species-mediated NET induction requires citrullination of arginine residues in histone proteins and subsequent chromatin de-condensation, we examined citrullination levels of histone in infected neutrophils. It is important to note that the citrullinated histone H3 was readily detected in neutrophils infected with the wild-type strain, as compared to infection with the spxB mutant strain. Moreover, decomposition of streptococcal H2O2 with catalase reduced NET induction. These results suggest that H2O2 produced by S. sanguinis provokes cell death of neutrophils and NET formation, thus potentially affecting bacterial survival in the bloodstream.

  3. Streptococcus sanguinis induces neutrophil cell death by production of hydrogen peroxide.

    Directory of Open Access Journals (Sweden)

    Ryuichi Sumioka

    Full Text Available Streptococcus is the dominant bacterial genus in the human oral cavity and a leading cause of infective endocarditis. Streptococcus sanguinis belongs to the mitis group of streptococci and produces hydrogen peroxide (H2O2 by the action of SpxB, a pyruvate oxidase. In this study, we investigated the involvement of SpxB in survival of S. sanguinis in human blood and whether bacterial H2O2 exhibits cytotoxicity against human neutrophils. Results of a bactericidal test with human whole blood revealed that the spxB mutation in S. sanguinis is detrimental to its survival in blood. When S. sanguinis strains were exposed to isolated neutrophils, the bacterial survival rate was significantly decreased by spxB deletion. Furthermore, human neutrophils exposed to the S. sanguinis wild-type strain, in contrast to those exposed to an spxB mutant strain, underwent cell death with chromatin de-condensation and release of web-like extracellular DNA, reflecting induction of neutrophil extracellular traps (NETs. Since reactive oxygen species-mediated NET induction requires citrullination of arginine residues in histone proteins and subsequent chromatin de-condensation, we examined citrullination levels of histone in infected neutrophils. It is important to note that the citrullinated histone H3 was readily detected in neutrophils infected with the wild-type strain, as compared to infection with the spxB mutant strain. Moreover, decomposition of streptococcal H2O2 with catalase reduced NET induction. These results suggest that H2O2 produced by S. sanguinis provokes cell death of neutrophils and NET formation, thus potentially affecting bacterial survival in the bloodstream.

  4. Molecular and antimicrobial susceptibility profiling of atypical Streptococcus species from porcine clinical specimens.

    Science.gov (United States)

    Moreno, Luisa Z; Matajira, Carlos E C; Gomes, Vasco T M; Silva, Ana Paula S; Mesquita, Renan E; Christ, Ana Paula G; Sato, Maria Inês Z; Moreno, Andrea M

    2016-10-01

    The Streptococcus species present broad phenotypic variation, making identification difficult using only traditional microbiological methods. Even though Streptococcus suis is the most important species for the worldwide swine industry, other Streptococcus species appear to be able to cause disease in swine and could represent a higher underestimated risk for porcine health. The aim of this study was to identify Streptococcus-like isolates by MALDI-TOF MS and 16S rRNA sequencing and further molecular and antibiotic susceptibility characterization of the atypical Streptococcus species capable of causing disease in swine. Fifty presumptive Streptococcus isolates from diseased pigs isolated from different Brazilian States between 2002 and 2014 were evaluated. Among the studied isolates, 26% were identified as Streptococcus hyovaginalis, 24% as Streptococcus plurianimalium, 12% as Streptococcus alactolyticus, 10% as Streptococcus hyointestinalis, and the remaining isolates belonged to Streptococcus henryi (6%), Streptococcus thoraltensis (6%), Streptococcus gallolyticus (6%), Streptococcus gallinaceus (4%), Streptococcus sanguinis (4%), and Streptococcus mitis (2%). The Streptococcus isolates were successfully identified by spectral cluster analysis and 16S rRNA sequencing with 96% of concordance between the techniques. The SE-AFLP analysis also supported Streptococcus species distinction and enabled further observation of higher genetic heterogeneity intra-species. The identified Streptococcus species presented variable MIC values to β-lactams, enrofloxacin and florfenicol, and high resistance rates to tetracyclines and macrolides, which appear to be directly related to the industry's antimicrobial usage and resistance selection. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Directory of Open Access Journals (Sweden)

    Chisato Morita

    Full Text Available Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease, and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs. Recombinant SWAN protein (rSWAN digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+ and Ca(2+ for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  6. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Science.gov (United States)

    Morita, Chisato; Sumioka, Ryuichi; Nakata, Masanobu; Okahashi, Nobuo; Wada, Satoshi; Yamashiro, Takashi; Hayashi, Mikako; Hamada, Shigeyuki; Sumitomo, Tomoko; Kawabata, Shigetada

    2014-01-01

    Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+) and Ca(2+) for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  7. Bacteriostatic effect of simvastatin on selected oral streptococci in vitro

    Directory of Open Access Journals (Sweden)

    Eugene J Whitaker

    2017-01-01

    Full Text Available Context and Objective: Simvastatin is a widely used cholesterol-lowering drug, which has been found to have a number of pleiotropic effects. The aim of this study was to evaluate the antimicrobial effectiveness of simvastatin against selected oral streptococci as determined by the minimum inhibitory concentration (MIC. Methods: Streptococcus mutans, Streptococcus sanguis, Streptococcus anginosus, and Streptococcus salivarius were the test microorganisms. The serial dilution method was used to determine the MIC of simvastatin against these organisms. The MIC was defined as the lowest concentration of simvastatin that completely inhibited growth of the test organisms. Results: The data indicate that simvastatin inhibits the growth of the test organisms, with MIC's ranging from 7.8 to 15.6 μg/ml. Conclusions: Simvastatin has MIC's against the selected bacteria that compare favorably with reported values for topical agents such as essential oil, chlorhexidine gluconate, and triclosan. The levels of simvastatin required to inhibit bacterial growth of oral bacteria exceed the reported levels of the drug found in plasma or crevicular fluid of patients who are treated with this cholesterol-lowering drug. However, clinical studies are warranted to investigate the potential use of simvastatin as a novel antiplaque agent that could be used in local drug delivery to the oral cavity of those patients who are prescribed this cholesterol-lowering drug.

  8. Detection of group D and viridans streptococci in blood by radiometric methods

    International Nuclear Information System (INIS)

    Beckwith, D.G.

    1979-01-01

    A prospective study was conducted to evaluate the radiometric detection of group D and viridans streptococci in blood, using three media preparations, Bactec 6A and 6B isotonic media and 8B hypertonic medium. All enterococci tested were detected by the 6A and 6B media. However, the 6A medium failed to detect 76% of the Streptococcus bovis isolates and 57% of the viridans streptococci, whereas all S. bovis isolates and 95% of the viridans streptococci were detected with the 6B formulation. No improvement in detection was noted in comparing the 6B and the 8B hypertonic media. The importance of adequate detection of this group of organisms, especially in patients with endocarditis, is discussed

  9. Biosurfactants from thermophilic dairy streptococci and their potential role in the fouling control of heat exchanger plates

    NARCIS (Netherlands)

    Busscher, HJ; vanderKuijlBooij, M; vanderMei, HC

    Recent work on biosurfactant release by thermophilic dairy streptococci is reviewed, There is a suggestion that Streptococcus thermophilus isolates may release biosurfactants that stimulate detachment of already-adhering cells and leave an anti-adhesive coating on a substratum. A previously

  10. Preventive effects of a phospholipid polymer coating on PMMA on biofilm formation by oral streptococci

    Science.gov (United States)

    Shibata, Yukie; Yamashita, Yoshihisa; Tsuru, Kanji; Ishihara, Kazuhiko; Fukazawa, Kyoko; Ishikawa, Kunio

    2016-12-01

    The regulation of biofilm formation on dental materials such as denture bases is key to oral health. Recently, a biocompatible phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB) coating, was reported to inhibit sucrose-dependent biofilm formation by Streptococcus mutans, a cariogenic bacterium, on the surface of poly(methyl methacrylate) (PMMA) denture bases. However, S. mutans is a minor component of the oral microbiome and does not play an important role in biofilm formation in the absence of sucrose. Other, more predominant oral streptococci must play an indispensable role in sucrose-independent biofilm formation. In the present study, the effect of PMB coating on PMMA was evaluated using various oral streptococci that are known to be initial colonizers during biofilm formation on tooth surfaces. PMB coating on PMMA drastically reduced sucrose-dependent tight biofilm formation by two cariogenic bacteria (S. mutans and Streptococcus sobrinus), among seven tested oral streptococci, as described previously [N. Takahashi, F. Iwasa, Y. Inoue, H. Morisaki, K. Ishihara, K. Baba, J. Prosthet. Dent. 112 (2014) 194-203]. Streptococci other than S. mutans and S. sobrinus did not exhibit tight biofilm formation even in the presence of sucrose. On the other hand, all seven species of oral streptococci exhibited distinctly reduced glucose-dependent soft biofilm retention on PMB-coated PMMA. We conclude that PMB coating on PMMA surfaces inhibits biofilm attachment by initial colonizer oral streptococci, even in the absence of sucrose, indicating that PMB coating may help maintain clean conditions on PMMA surfaces in the oral cavity.

  11. The pathogenic persona of community-associated oral streptococci.

    Science.gov (United States)

    Whitmore, Sarah E; Lamont, Richard J

    2011-07-01

    The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes that contribute to the development of pathogenic oral communities. MGS adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as Porphyromonas gingivalis, and the two species assemble into heterotypic communities. Close physical association facilitates physiologic support, and pathogens such as Aggregatibacter actinomycetemcomitans display resource partitioning to favour carbon sources generated by streptococcal metabolism. MGS exchange information with community members through a number of interspecies signalling systems including AI-2 and contact dependent mechanisms. Signal transduction systems induced in P. gingivalis are based on protein dephosphorylation mediated by the tyrosine phosphatase Ltp1, and converge on a LuxR-family transcriptional regulator, CdhR. Phenotypic responses in P. gingivalis include regulation of hemin uptake systems and gingipain activity, processes that are intimately linked to the virulence of the organism. Furthermore, communities of S. gordonii with P. gingivalis or with A. actinomycetemcomitans are more pathogenic in animal models than the constituent species alone. We propose that MGS should be considered accessory pathogens, organisms whose pathogenic potential only becomes evident in the context of a heterotypic microbial community. © 2011 Blackwell Publishing Ltd.

  12. Human T-cell responses to oral streptococci in human PBMC-NOD/SCID mice.

    Science.gov (United States)

    Salam, M A; Nakao, R; Yonezawa, H; Watanabe, H; Senpuku, H

    2006-06-01

    We investigated cellular and humoral immune responses to oral biofilm bacteria, including Streptococcus mutans, Streptococcus anginosus, Streptococcus sobrinus, and Streptococcus sanguinis, in NOD/SCID mice immunized with human peripheral blood mononuclear cells (hu-PBMC-NOD/SCID mice) to explore the pathogenicity of each of those organisms in dental and oral inflammatory diseases. hu-PBMC-NOD/SCID mice were immunized by intraperitoneal injections with the whole cells of the streptococci once a week for 3 weeks. FACS analyses were used to determine the percentages of various hu-T cell types, as well as intracellular cytokine production of interleukin-4 and interferon-gamma. Serum IgG and IgM antibody levels in response to the streptococci were also determined by enzyme-linked immunosorbent assay. S. anginosus induced a significant amount of the proinflammatory cytokine interferon-gamma in CD4(+) and CD8(+) T cells in comparison with the other streptococci. However, there was no significant differences between the streptococci in interleukin-4 production by CD4(+) and CD8(+) T cells after inoculation. Further, S. mutans significantly induced human anti-S. mutans IgG, IgG(1), IgG(2), and IgM antibodies in comparison with the other organisms. In conclusion, S. anginosus up-regulated Th1 and Tc1 cells, and S. mutans led to increasing levels of their antibodies, which was associated with the induction of Th2 cells. These results may contribute to a better understanding of human lymphocyte interactions to biofilm bacteria, along with their impact on dental and mucosal inflammatory diseases, as well as endocarditis.

  13. Effect of Date Extract on Growth of Mutans Streptococci, the Most Important Factor of Dental Caries

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    A Sayyedi

    2007-01-01

    Full Text Available ABSTRACT: Introduction & Objective:Dental caries is perhaps the most common bacterial infections in humans and Streptococcus Mutans is one of the most important factors in dental caries. Research has shown that some kind foods have an inhibitory effect on cariogenic factors of Mutans streptococci. The aim of this study was to investigate the effect of date extract on growth of Streptococcus Mutans. Methods & Materials: This experimental study was down at faculty of medicine, Yasuj university of medical sciences with collaborative of microbiology department of Shiraz university of medical sciences in 2005. In an In-vitro study, effect of date extract on growth of Mutans Streptococci was surveyed .After collecting of Streptococcus Mutans from dental caries those were cultured in different medium of date fruit, extract of date fruit and syrup of date with different concentrations. Results: Following 24 hours, Streptococcus mutans was grown in less concentration of date mediums and its grown was inhibited in more concentrations. Conclusion: With respect of inhibitory effect of date extract on growth of Streptococcus mutans,it might be introduced that date as a source of food has a preventive effect on dental caries.

  14. PCR detection and identification of oral streptococci in saliva samples using gtf genes.

    Science.gov (United States)

    Hoshino, Tomonori; Kawaguchi, Mamoru; Shimizu, Noriko; Hoshino, Naoko; Ooshima, Takashi; Fujiwara, Taku

    2004-03-01

    Oral streptococci are major constituents of dental plaque, and their prevalence is implicated in various pathologies. Therefore, accurate identification of oral streptococci would be valuable for studies of cariogenic plaque and for diagnostic use in infective endocarditis. Many oral streptococci possess glucosyltransferase enzymes that synthesize glucan, which is an obligate component of dental plaque. We established a rapid and precise method to identify oral streptococci by PCR using the species-specific region from the glucosyltransferase gene. With the species-specific primers, Streptococcus mutans, S. sobrinus, S. salivarius, S. sanguinis, S. oralis, and S. gordonii could be successfully distinguished. Further, we developed a simple method to extract the bacterial DNA from saliva. Using the resultant DNA as a template, the proposed PCR detection was performed. Their distribution was in accord with results of conventional biochemical tests. These findings indicate that the present PCR method is useful for the analysis of oral streptococci and can be successfully used in clinical applications to identify pathogenic bacteria associated with oral infectious disease and/or endocarditis.

  15. Antimicrobial susceptibility against penicillin, ampicillin and vancomycin of viridans group Streptococcus in oral microbiota of patients at risk of infective endocarditis.

    Science.gov (United States)

    Süzük, Serap; Kaşkatepe, Banu; Çetin, Mustafa

    2016-09-01

    The viridans group Streptococci (VGS) are most abundant in the mouth; in some instances they might emerge as pathogens particularly in infective endocarditis (IE). In this study, we aimed to define and determine the susceptibility against antibiotics of VGS that are members of the oral microbiota of patients exhibiting a risk of developing IE. Forty-nine patients at risk of infective endocarditis were included in the study. Identification of the bacteria was performed using API STREP (bioMérieux, France). Gradient test strips (E-Test, France) were used to determine MIC of the bacteria against penicillin, ampicillin, and vancomycin. The distribution of the isolated VGS groups was determined as follows: Streptococcus mitis 32.6% and anginosus group - 32.6%, S. sanguinis group - 16.3%, S. mutans group - 12.2%, and S. salivarius group - 6.1%. The rates of resistance and reduced sensitivity of the isolates for penicillin and ampicillin were determined at 61.2% and 55.1%, respectively. However, all isolates were found to be susceptible to vancomycin. We conclude that the antimicrobial resistance of VGS should be determined on a regular basis locally, and decisions on therapeutic and prophylactic interventions should be given taking this resistance into consideration.

  16. Reduced salivary flow and colonization by mutans streptococci in children with Down syndrome

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    Cristina Areias

    2012-09-01

    Full Text Available OBJECTIVES: Although individuals with Down syndrome have considerable oral disease, the prevalence of dental caries in this group is low. The present study aimed to compare known risk factors for dental caries development in children with Down syndrome and a matched population (siblings. In both populations, the number of acidogenic microorganisms, such as mutans streptococci, lactobacilli and Candida species, and the paraffin-stimulated pH, flow rate and IgA concentration in whole saliva were evaluated and compared. METHOD: Saliva was collected, and the caries index was evaluated in 45 sibling pairs aged between 6 and 18 years old. The salivary IgA concentration was determined by immunoturbidimetry. Salivary mutans streptococci, lactobacilli and Candida species were quantified on mitis salivarius agar containing bacitracin and 20% sucrose, rogosa agar supplemented with glacial acetic acid and sabouraud agar supplemented with chloramphenicol, respectively. RESULTS: Down syndrome children had a higher caries-free rate (p<0.05 and lower salivary mutans streptococci counts (p<0.03 compared to their siblings. Similar numbers of lactobacilli and Candida species were found in both groups. Salivary flow rates were 36% lower in Down syndrome children compared to their siblings (p<0.05. The salivary pH did not differ between Down syndrome children and controls. The Down syndrome children had an IgA secretion rate 29% lower than that of their siblings, but this difference was not statistically significant. CONCLUSIONS: In conclusion, the lower number of mutans streptococci in the saliva may be one of the factors contributing to the lower caries rate observed in Down syndrome children, despite evidence of hyposalivation.

  17. Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage.

    Science.gov (United States)

    Sheng, Jiangyun; Baldeck, Jeremiah D; Nguyen, Phuong T M; Quivey, Robert G; Marquis, Robert E

    2010-07-01

    Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. L-Malic acid was rapidly fermented to L-lactic acid and CO(2) by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses.

  18. Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage

    Science.gov (United States)

    Sheng, Jiangyun; Baldeck, Jeremiah D.; Nguyen, Phuong T.M.; Quivey, Robert G.; Marquis, Robert E.

    2011-01-01

    Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. l-Malic acid was rapidly fermented to l-lactic acid and CO2 by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses. PMID:20651853

  19. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

    Directory of Open Access Journals (Sweden)

    Guillermo Hugo Peralta

    Full Text Available ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

  20. Pulsed-field gel electrophoresis (PFGE): application in population structure studies of bovine mastitis-causing streptococci.

    Science.gov (United States)

    Santos-Sanches, Ilda; Chambel, Lélia; Tenreiro, Rogério

    2015-01-01

    Pulsed-field gel electrophoresis (PFGE) separates large DNA molecules by the use of an alternating electrical field, such that greater size resolution can be obtained when compared to normal agarose gel electrophoresis. PFGE is often employed to track pathogens and is a valuable typing scheme to detect and differentiate strains. Particularly, the contour-clamped homogeneous electric field (CHEF) PFGE system is considered to be the gold standard for use in epidemiological studies of many bacterial pathogens. Here we describe a PFGE protocol that was applicable to the study of bovine streptococci, namely, Streptococcus agalactiae (group B Streptococcus, GBS), Streptococcus dysgalactiae subsp. dysgalactiae (group C Streptococcus, GCS), and Streptococcus uberis-which are relevant pathogens causing mastitis, a highly prevalent and costly disease in dairy industry due to antibiotherapy and loss in milk production.

  1. Streptococcus sinensis may react with Lancefield group F antiserum.

    Science.gov (United States)

    Woo, Patrick C Y; Teng, Jade L L; Leung, Kit-wah; Lau, Susanna K P; Tse, Herman; Wong, Beatrice H L; Yuen, Kwok-yung

    2004-11-01

    Lancefield group F streptococci have been found almost exclusively as members of the 'Streptococcus milleri' group, although they have been reported very occasionally in some other streptococcal species. Among 302 patients with bacteraemia caused by viridans streptococci over a 6-year period, three cases were caused by Streptococcus sinensis (type strain HKU4T, HKU5 and HKU6). All three patients had infective endocarditis complicating their underlying chronic rheumatic heart diseases. Gene sequencing showed no base differences between the 16S rRNA gene sequences of HKU5 and HKU6 and that of HKU4T. All three strains were Gram-positive, non-spore-forming cocci arranged in chains. All grew on sheep blood agar as alpha-haemolytic, grey colonies of 0.5-1 mm in diameter after 24 h incubation at 37 degrees C in ambient air. Lancefield grouping revealed that HKU5 and HKU6 were Lancefield group F, but HKU4T was non-groupable with Lancefield groups A, B, C, D, F or G antisera. HKU4T was identified by the Vitek system (GPI), API system (20 STREP) and ATB system (ID32 STREP) as 99 % Streptococcus intermedius, 51.3 % S. intermedius and 99.9 % Streptococcus anginosus, respectively. Using the same tests, HKU5 was identified as 87 % Streptococcus sanguinis/Streptococcus gordonii, 59 % Streptococcus salivarius and 99.6 % S. anginosus, respectively, and HKU6 as 87 % S. sanguinis/S. gordonii, 77 % Streptococcus pneumoniae and 98.3 % S. anginosus, respectively. The present data revealed that a proportion of Lancefield group F streptococci could be S. sinensis. Lancefield group F streptococci should not be automatically reported as 'S. milleri'.

  2. Evaluation of hyperimmune colostrum production in bovine against cariogenic streptococci and its impact on growth and bacterial biofilm formation

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    Fateme Ramezanalizadeh

    2017-03-01

    Full Text Available Background and Aims: Dental caries is the most common infectious diseases. Among the oral bacteria, Streptococcus mutans and Streptococcus sobrinus are considered as the main causes of tooth decay. The aim of this study was to evaluate the production of hyperimmune bovine colostrum containing specific antibodies against cariogenic bacteria and its antimicrobial effects on the growth and adhesion of Streptococcus mutans and Streptococcus sobrinus in the laboratory. Materials and Methods: In this experimental study, three pregnant bovine immunized with killed antigens of strains of Streptococcus mutans, Streptococcus mutans with Streptococcus Sobrinus and Streptococcus sobrinus through intramuscular injections. After delivery, The colostrum samples were collected, and the changes of anti-streptococci antibodies titers in colostrum and serum were determined by agglutination. Also,their antimicrobial effects against the growth and adhesion of oral streptococci were surveyed by the microtiter plate method. Data were analysed by One-Wey ANOVA in SPSS software. Results: The results showed that in hyperimmunized bovine , the antibodies titers against injected bacteria were from 1.1000 to 1.3000 in sera samples and from 1.320 to 1.1280 in whey of colostrum samples. Colostrum of hyperimmune cows reduced the attachment of Streptococcus mutans and Streptococcus Sobrinus about 69 and 43 percents, respectively and also, the low dilutions of it reduced bacterial growth. Conclusion:  According to the antibacterial effect immune colostrum on two strains of cariogenic bacteria in vitro, It appears that this material could be useful in the prevention and control of dental caries.

  3. Liamocin oil from Aureobasidium pullulans has antibacterial activity with specificity for species of Streptococcus

    Science.gov (United States)

    Liamocin oil from Aureobasidium pullulans NRRL 50380 was tested for antibacterial activity. Liamocins inhibited growth of Streptococcus agalactiae, S. uberis, S. mitis, S. infantarius, and S. mutans, with minimum inhibitory concentrations from 20 'g/ml to 78 'g/ml. Enterococcus faecalis was less sus...

  4. Competence without a competence pheromone in a natural isolate of Streptococcus infantis

    DEFF Research Database (Denmark)

    Ween, O; Teigen, S; Gaustad, P

    2002-01-01

    C and a two-component regulatory system encoded by comDE. Here we report that a natural isolate of a mitis group streptococcus (Atu-4) is competent for genetic transformation even though it has lost the gene encoding the competence pheromone. In contrast to other strains, induction of competence in Atu-4...

  5. Antimicrobial photodynamic therapy with two photosensitizers on two oral streptococci: an in vitro study

    Science.gov (United States)

    Vahabi, S.; Fekrazad, R.; Ayremlou, S.; Taheri, S.; Lizarelli, R. F. Z.; Kalhori, K. A. M.

    2011-12-01

    Periodontal diseases are caused by infection of tissues supporting the teeth due to complex aggregate of bacteria known as biofilm and firstly colonized by streptococci. The aim of this in vitro study was to evaluate the effect of Radachlorin® and Toluidine Blue O (TBO)-mediated photodynamic therapy (PDT) on the viability of two oral streptococci. Bacterial suspensions of Streptococcus mutans and Streptococcus sanguis were subjected to either TBO or Radachlorin®, Then exposed to two different diode laser light at energy densities of 3, 6 J/cm2 at 633 nm and 6, 12 J/cm2 at 662 nm, respectively. The control groups were subjected to laser light alone, photosensitizer alone or received neither photosensitizer nor light exposure. The suspensions were then spread over specific agar mediums and viable microorganisms were counted after overnight incubation aerobically at 37°C, 5% CO2 and then reported as colony forming unit. The results indicated that photosensitization by the energy density of 6 J/cm2 with Radachlorin® and both 3 and 6 J/cm2 with TBO caused significant reduction in bacterial colony formation ( p < 0.05). Radachlorin® and TBO-mediated photodynamic therapy seem to show excellent potential in significantly killing of two oral streptococci in vitro.

  6. Semi-Quantitative Method for Streptococci Magnetic Detection in Raw Milk

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    Carla Duarte

    2016-04-01

    Full Text Available Bovine mastitis is the most costly disease for dairy farmers and the most frequent reason for the use of antibiotics in dairy cattle; thus, control measures to detect and prevent mastitis are crucial for dairy farm sustainability. The aim of this study was to develop and validate a sensitive method to magnetically detect Streptococcus agalactiae (a Group B streptococci and Streptococcus uberis in raw milk samples. Mastitic milk samples were collected aseptically from 44 cows with subclinical mastitis, from 11 Portuguese dairy farms. Forty-six quarter milk samples were selected based on bacterial identification by conventional microbiology. All samples were submitted to PCR analysis. In parallel, these milk samples were mixed with a solution combining specific antibodies and magnetic nanoparticles, to be analyzed using a lab-on-a-chip magnetoresistive cytometer, with microfluidic sample handling. This paper describes a point of care methodology used for detection of bacteria, including analysis of false positive/negative results. This immunological recognition was able to detect bacterial presence in samples spiked above 100 cfu/mL, independently of antibody and targeted bacteria used in this work. Using PCR as a reference, this method correctly identified 73% of positive samples for streptococci species with an anti-S. agalactiae antibody, and 41% of positive samples for an anti-GB streptococci antibody.

  7. Variation on a theme; an overview of the Tn916 / Tn1545 family of mobile genetic elements in the oral and nasopharyngeal streptococci.

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    Francesco eSantoro

    2014-10-01

    Full Text Available The oral and nasopharyngeal streptococci are a major part of the normal microbiota in humans. Most human associated streptococci are considered commensals however a small number of them are pathogenic, causing a wide range of diseases including oral infections such as dental caries and periodontitis and diseases at other body sites including sinusitis and endocarditis, and in the case of Streptococcus pneumoniae, meningitis. Both phenotypic and sequence based studies have shown that the human associated streptococci from the mouth and nasopharynx harbour a large number of antibiotic resistance genes and these are often located on mobile genetic elements known as conjugative transposons or integrative and conjugative elements of the Tn916 / Tn1545 family. These mobile genetic elements are responsible for the spread of the resistance genes between streptococci and also between streptococci and other bacteria. In this review we describe the resistances conferred by, and the genetic variations between the many different Tn916-like elements found in recent studies of oral and nasopharyngeal streptococci and show that Tn916-like elements are important mediators of antibiotic resistance genes within this genus. We will also discuss the role of the oral environment and how this is conducive to the transfer of these elements and discuss the contribution of both transformation and conjugation on the transfer and evolution of these elements in different streptococci.

  8. Short communication: Genotypic and phenotypic identification of environmental streptococci and association of Lactococcus lactis ssp. lactis with intramammary infections among different dairy farms.

    Science.gov (United States)

    Werner, B; Moroni, P; Gioia, G; Lavín-Alconero, L; Yousaf, A; Charter, M E; Carter, B Moslock; Bennett, J; Nydam, D V; Welcome, F; Schukken, Y H

    2014-11-01

    Lactococcus species are counted among a large and closely related group of environmental streptococci and streptococci-like bacteria that include bovine mastitis pathogenic Streptococcus, Enterococcus, and Aerococcus species. Phenotypic and biochemical identification methods can be inaccurate and unreliable for species within this group, particularly for Lactococcus spp. As a result, the incidence of Lactococcus spp. on the farm may have been historically underreported and consequently little is known about the clinical importance of this genus as a mastitis pathogen. We used molecular genetic identification methods to accurately differentiate 60 environmental streptococci and streptococci-like bacteria isolated from cows with high somatic cell count and chronic intramammary infection (IMI; >2 somatic cell scores above 4) among 5 geographically distinct farms in New York and Minnesota that exhibited an observed increase in IMI. These isolates were phenotypically identified as Streptococcus uberis and Streptococcus spp. Genetic methods identified 42 isolates (70%) as Lactococcus lactis ssp. lactis, including all 10 isolates originally phenotypically identified as Streptococcus uberis. Antibiotic inhibition testing of all Lc. lactis ssp. lactis showed that 7 isolates were resistant to tetracycline. In the present study, a predominance of Lc. lactis ssp. lactis was identified in association with chronic, clinical bovine IMI among all 5 farms and characterized antimicrobial resistance for treatment therapies. Routine use by mastitis testing labs of molecular identification methods for environmental streptococci and streptococci-like bacteria can further define the role and prevalence of Lc. lactis ssp. lactis in association with bovine IMI and may lead to more targeted therapies. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. Streptococcus iniae and Streptococcus agalactiae

    Science.gov (United States)

    Streptococcus iniae and S. agalactiae are economically important Gram positive bacterial pathogens of cultured and wild fish with a worldwide distribution. Both bacteria are potential zoonotic pathogens and have been associated most often with infections in immunocompromised people. Streptococcus in...

  10. Radioimmunoassay of serum antibodies with B-streptococcus specificity in pregnant women and infants

    International Nuclear Information System (INIS)

    Frey, C.W.

    1980-01-01

    In a specific competitive radioimmunoassay of purified rabbit antibodies, labeled with iodine 125 against group- and type-antigens of streptococcus agalactiae (streptococci type B), we investigated the amount of serum anti-bodies providing specificity of streptococci type B in not preselected pregnant women, newborn and babies with colonies of streptococci type B or with diseases due to streptococci type B and in some of their mothers. These antibodies could be detected in 26 of 45 pregnant women and in 3 of 7 children with colonies of streptococci type B. 5 of 18 newborn with the ''early-onset'' type of infection and 6 of 7 of their mothers provided antibodies with specificity of streptococci type B as did one of two newborn with the ''late onset'' type of infection. Contrary to the supposition of Baker and Kasper and in accordance with the findings of Wilkinson, the ''risk group'' cannot be determined only by detecting the antibodies against streptococci type B. The risk group comprises those persons in whom the colonisation of streptococci agalactiae leads to the frequently life-threatening infecton of neonatals with streptococci type B. (orig.) [de

  11. Invasion of human aortic endothelial cells by oral viridans group streptococci and induction of inflammatory cytokine production.

    Science.gov (United States)

    Nagata, E; de Toledo, A; Oho, T

    2011-02-01

    Oral viridans group streptococci are the major commensal bacteria of the supragingival oral biofilm and have been detected in human atheromatous plaque. Atherosclerosis involves an ongoing inflammatory response, reportedly involving chronic infection caused by multiple pathogens. The aim of this study was to examine the invasion of human aortic endothelial cells (HAECs) by oral viridans group streptococci and the subsequent cytokine production by viable invaded HAECs. The invasion of HAECs by bacteria was examined using antibiotic protection assays and was visualized by confocal scanning laser microscopy. The inhibitory effects of catalase and cytochalasin D on the invasion of HAECs were also examined. The production of cytokines by invaded or infected HAECs was determined using enzyme-linked immunosorbent assays, and a real-time polymerase chain reaction method was used to evaluate the expression of cytokine messenger RNA. The oral streptococci tested were capable of invading HAECs. The number of invasive bacteria increased with the length of the co-culture period. After a certain co-culture period, some organisms were cytotoxic to the HAECs. Catalase and cytochalasin D inhibited the invasion of HAECs by the organism. HAECs invaded by Streptococcus mutans Xc, Streptococcus gordonii DL1 (Challis), Streptococcus gordonii ATCC 10558 and Streptococcus salivarius ATCC 13419 produced more cytokine(s) (interleukin-6, interleukin-8, monocyte chemoattractant protein-1) than non-invaded HAECs. The HAECs invaded by S. mutans Xc produced the largest amounts of cytokines, and the messenger RNA expression of cytokines by invaded HAECs increased markedly compared with that by non-invaded HAECs. These results suggest that oral streptococci may participate in the pathogenesis of atherosclerosis. © 2010 John Wiley & Sons A/S.

  12. Antimicrobial resistance and molecular epidemiology of streptococci from bovine mastitis

    DEFF Research Database (Denmark)

    Rato, Márcia G.; Bexiga, Ricardo; Florindo, Carlos

    2013-01-01

    Streptococcus agalactiae (Group B Streptococcus, GBS), Streptococcus dysgalactiae subsp. dysgalactiae (Group C Streptococcus, GCS) and Streptococcus uberis are relevant mastitis pathogens, a highly prevalent and costly disease in dairy industry due to antibiotherapy and loss in milk production. T...

  13. Antimicrobial Susceptibility Patterns of Environmental Streptococci Recovered from Bovine Milk Samples in the Maritime Provinces of Canada

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    Marguerite Cameron

    2016-09-01

    Full Text Available Determination of antimicrobial susceptibility of bovine mastitis pathogens is important for guiding antimicrobial treatment decisions and for the detection of emerging resistance. Environmental streptococci are ubiquitous in the farm environment and are a frequent cause of mastitis in dairy cows. The aim of the study was to determine patterns of antimicrobial susceptibility among species of environmental streptococci isolated from dairy cows in the Maritime Provinces of Canada. The collection consisted of 192 isolates identified in milk samples collected from 177 cows originating from 18 dairy herds. Results were aggregated into: 1 Streptococcus uberis (n = 70, 2 Streptococcus dysgalactiae (n = 28, 3 other Streptococci spp. (n = 35, 4, Lactococcus spp. (n = 32, and 5 Enterococcus spp. (n = 27. Minimum inhibitory concentrations (MIC were determined using the Sensititre microdilution system and mastitis plate format. Multilevel logistic regression models were used to analyze the data, with antimicrobial susceptibility as the outcome. The proportion of susceptible Streptococcus uberis ranged from 23% (for penicillin to 99% (for penicillin/novobiocin, with a median of 82%. All Streptococcus dysgalactiae were susceptible to all antimicrobials except for penicillin (93% susceptible and tetracycline (18% susceptible. The range of susceptibility for other Streptococcus spp. was 43% (for tetracycline to 100%, with a median percent susceptibility of 92%. Lactococcus spp. isolates displayed percent susceptibilities ranging from 0% (for penicillin to 97% (for erythromycin, median 75%. For the antimicrobials tested, the MIC were higher for Enterococcus spp. than for the other species. According to the multilevel models, there was a significant interaction between antimicrobial and bacterial species, indicating that susceptibility against a particular antimicrobial varied among the species of environmental streptococci and vice versa. Generally

  14. Interactions between Oral Bacteria: Inhibition of Streptococcus mutans Bacteriocin Production by Streptococcus gordonii

    OpenAIRE

    Wang, Bing-Yan; Kuramitsu, Howard K.

    2005-01-01

    Streptococcus mutans has been recognized as an important etiological agent in human dental caries. Some strains of S. mutans also produce bacteriocins. In this study, we sought to demonstrate that bacteriocin production by S. mutans strains GS5 and BM71 was mediated by quorum sensing, which is dependent on a competence-stimulating peptide (CSP) signaling system encoded by the com genes. We also demonstrated that interactions with some other oral streptococci interfered with S. mutans bacterio...

  15. Viridans Streptococci in Peritoneal Dialysis Peritonitis: Clinical Courses and Long-Term Outcomes

    Science.gov (United States)

    Chao, Chia-Ter; Lee, Szu-Ying; Yang, Wei-Shun; Chen, Huei-Wen; Fang, Cheng-Chung; Yen, Chung-Jen; Chiang, Chih-Kang; Hung, Kuan-Yu; Huang, Jenq-Wen

    2015-01-01

    ♦ Background: The clinical courses and long-term outcomes of viridans streptococcus (VS) peritoneal dialysis (PD) peritonitis remain unclear. ♦ Methods: We conducted a retrospective analysis of all PD patients in a single center with gram-positive cocci (GPC) peritonitis between 2005 and 2011, and divided them into 3 groups: VS, other streptococci and other GPC (apart from VS). Clinical characteristics and outcomes of the VS group were compared with the other streptococci and other GPC groups, with prognostic factors determined. ♦ Results: A total of 140 patients with 168 episodes of GPC peritonitis (44% of all peritonitis) were identified over 7 years. Among these, 18 patients (13%) developed VS peritonitis, while 14 patients (10%) developed other streptococcal peritonitis. Patients with VS peritonitis had a high cure rate by antibiotic alone (94%), despite a high polymicrobial yield frequency (28%). We found that VS peritonitis carried a lower risk of Tenckhoff catheter removal and relapsing episodes than other GPC peritonitis (6% vs 11%), and a lower mortality than other streptococci peritonitis (0% vs 7%). However, after the index peritonitis episodes, VS, other streptococci, and other GPC group had a significantly increased peritonitis incidence compared with the period before the index peritonitis (all p peritonitis had a significantly higher incidence of refractory peritonitis compared with other streptococci or other GPC peritonitis in the long term (both p peritonitis after the index episode as compared with other streptococcal or GPC peritonitis. It might be prudent to monitor the technique of these patients with VS peritonitis closely to avoid further peritonitis episodes. PMID:24497584

  16. Capsular Polysaccharide Expression in Commensal Streptococcus Species

    DEFF Research Database (Denmark)

    Skov Sørensen, Uffe B; Yao, Kaihu; Yang, Yonghong

    2016-01-01

    Expression of a capsular polysaccharide is considered a hallmark of most invasive species of bacteria, including Streptococcus pneumoniae, in which the capsule is among the principal virulence factors and is the basis for successful vaccines. Consequently, it was previously assumed that capsule....... pneumoniae evolved by import of cps fragments from commensal Streptococcus species, resulting in a mosaic of genes of different origins. The demonstrated antigenic identity of at least eight of the numerous capsular polysaccharide structures expressed by commensal streptococci with recognized serotypes of S...... of Streptococcus pneumoniae and is the basis for successful vaccines against infections caused by this important pathogen. Contrasting with previous assumptions, this study showed that expression of capsular polysaccharides by the same genetic mechanisms is a general property of closely related species...

  17. MITI revises outlooks for energy and power demand

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    The Ministry of International Trade and Industry has revised downward its long-term outlook on energy supply and demand, lowering the estimated primary energy demand for fiscal 2000 from 600 million tons in oil equivalent to 540 MTOE, and reducing total power demand for fiscal 2000 from 899.1 billion kWh to 838 billion. In this content, the outlook for installed nuclear capacity has been revised downward from 62,000 MW to 53,500 MW. This revision of the power supply-demand outlook was reported on Oct. 1 to the supply and demand committee (Chairman - Yoshihiko Morozumi, Adviser to Nippon Schlum-berger) of the Electric Utility Industry Council; the energy supply-demand outlook was decided on Oct. 14 by the MITI Supply and Demand Subcommittee of the Advisory Committee for Energy and reported on Oct. 16 to the conference of ministers concerned with energy. (author)

  18. Using Matrix-Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) Complemented with Selected 16S rRNA and gyrB Genes Sequencing to Practically Identify Clinical Important Viridans Group Streptococci (VGS).

    Science.gov (United States)

    Zhou, Menglan; Yang, Qiwen; Kudinha, Timothy; Zhang, Li; Xiao, Meng; Kong, Fanrong; Zhao, Yupei; Xu, Ying-Chun

    2016-01-01

    There are challenges in viridans group streptococci (VGS) identification especially for the mitis group. Few studies have investigated the performance of MALDI-TOF MS system in VGS identification. Using 16S rRNA gene and gyrB gene sequencing as a gold standard, the performance of two MALDI-TOF MS instruments in the identification of 181 VGS clinical isolates was studied. The Bruker Biotyper and Vitek MS IVD systems correctly identified 88.4% and 98.9% of the 181 isolates, respectively. The Vitek MS RUO system was the least reliable, only correctly identifying 38.7% of the isolates to species level with several misidentifications and invalid results. The Bruker Biotyper system was very unreliable in the identification of species within the mitis group. Among 22 non-pneumococci isolates (S. mitis/S. oralis/S. pseudopneumoniae), Biotyper misidentified 21 of them as S. pneumoniae leading to a low sensitivity and low positive predictive value in these species. In contrast, the Vitek MS IVD demonstrated a better resolution for pneumococci and non-pneumococci despite the inability to distinguish between S. mitis/S. oralis. For more accurate species-level identification, further improvements in the VGS spectra databases are needed. Based on MALDI-TOF analysis and selected 16S rRNA gene plus gyrB genes sequencing, we designed a practical VGS identification algorithm.

  19. Effect of Chocobar Ice Cream Containing Bifidobacterium on Salivary Streptococcus mutans and Lactobacilli: A Randomised Controlled Trial.

    Science.gov (United States)

    Nagarajappa, Ramesh; Daryani, Hemasha; Sharda, Archana J; Asawa, Kailash; Batra, Mehak; Sanadhya, Sudhanshu; Ramesh, Gayathri

    2015-01-01

    To examine the effect of chocobar ice cream containing bifidobacteria on salivary mutans streptococci and lactobacilli. A double-blind, randomised controlled trial was conducted with 30 subjects (18 to 22 years of age) divided into 2 groups, test (chocobar ice cream with probiotics) and control (chocobar ice cream without probiotics). The subjects were instructed to eat the allotted chocobar ice cream once daily for 18 days. Saliva samples collected at intervals were cultured on Mitis Salivarius agar and Rogosa agar and examined for salivary mutans streptococci and lactobacilli, respectively. The Mann-Whitney U-test, Friedman and Wilcoxon signed-rank tests were used for statistical analysis. Postingestion in the test group, a statistically significant reduction (p ice cream containing probiotic bifidobacteria may reduce salivary levels of mutans streptococci in young adults.

  20. Linear response of mutans streptococci to increasing frequency of xylitol chewing gum use: a randomized controlled trial [ISRCTN43479664

    Directory of Open Access Journals (Sweden)

    Yamaguchi David K

    2006-03-01

    Full Text Available Abstract Background Xylitol is a naturally occurring sugar substitute that has been shown to reduce the level of mutans streptococci in plaque and saliva and to reduce tooth decay. It has been suggested that the degree of reduction is dependent on both the amount and the frequency of xylitol consumption. For xylitol to be successfully and cost-effectively used in public health prevention strategies dosing and frequency guidelines should be established. This study determined the reduction in mutans streptococci levels in plaque and unstimulated saliva to increasing frequency of xylitol gum use at a fixed total daily dose of 10.32 g over five weeks. Methods Participants (n = 132 were randomized to either active groups (10.32 g xylitol/day or a placebo control (9.828 g sorbitol and 0.7 g maltitol/day. All groups chewed 12 pieces of gum per day. The control group chewed 4 times/day and active groups chewed xylitol gum at a frequency of 2 times/day, 3 times/day, or 4 times/day. The 12 gum pieces were evenly divided into the frequency assigned to each group. Plaque and unstimulated saliva samples were taken at baseline and five-weeks and were cultured on modified Mitis Salivarius agar for mutans streptococci enumeration. Results There were no significant differences in mutans streptococci level among the groups at baseline. At five-weeks, mutans streptococci levels in plaque and unstimulated saliva showed a linear reduction with increasing frequency of xylitol chewing gum use at the constant daily dose. Although the difference observed for the group that chewed xylitol 2 times/day was consistent with the linear model, the difference was not significant. Conclusion There was a linear reduction in mutans streptococci levels in plaque and saliva with increasing frequency of xylitol gum use at a constant daily dose. Reduction at a consumption frequency of 2 times per day was small and consistent with the linear-response line but was not statistically

  1. A Study of Streptococcus Viridans in the Maxillofacial Region

    Directory of Open Access Journals (Sweden)

    Y. Refoua

    2005-12-01

    Full Text Available Statement of Problem: Streptococcus viridans is one of the most important microorganisms in the establishment of infections leading to dental caries and heart valve damages. Therefore the diagnosis and prevention of these infections is critical in health care.Purpose: The aim of this in-vivo study was to determine the prevalence of viridans streptococci in abscesses occurring in the maxillofacial region.Materials and Methods: The study sample consisted of 39 patients with maxillofacial abscesses, referred to the Department of Oral Surgery Faculty of Dentistry Tehran University of Medical Sciences and Dr. Shariati Hospital, Tehran University of Medical Sciences. Extra-oral incision, drainage and pus collection followed by culture, staining and biochemical and sugar fermentation tests were carried out for all participants.Results: In the present study %53.84 and 46.16% of the patients had negative and positive culture results, respectively. In the positive culture group, %2.5 of the viridans streptococci were streptococcus salivarius, %4.6 streptococcus sanguis and %17.9 were streptococcus mutans.Conclusion: The findings of this study showed that viridans streptococci are an important factor in the development of metastatic and maxillofacial infections which can pose a significant threat to the patient’s life.

  2. Amino acids transport in lactic streptococci

    NARCIS (Netherlands)

    Driessen, Arnold Jacob Mathieu

    1987-01-01

    Lactic streptococci are extremely fastidious bacteria. For growth an exogenous source of amino acids and other nutrients is essential. The amino acid requirement in milk is fulfilled by the milk-protein casein, which is degraded by sequential hydrolysis, involving proteases and peptidases. ... Zie:

  3. Bacteremia with the bovis group streptococci

    DEFF Research Database (Denmark)

    Marmolin, Ea S; Hartmeyer, Gitte N; Christensen, Jens Jørgen

    2016-01-01

    DNA sequencing of the intergenic spacer (ITS) region was used to identify 53 blood culture isolates that had previously been designated to the bovis group streptococci and clinical data was collected retrospectively from patients' records using a standardized protocol. ITS sequencing identified 19....... pasteurianus (58.7%) bacteremia calls for intensive investigation for underlying disease focusing on the pancreas and the hepatobiliary system....

  4. Identification and characterization of two temperature-induced surface-associated proteins of Streptococcus suis with high homologies to members of the arginine deiminase system of Streptococcus pyogenes

    NARCIS (Netherlands)

    Winterhoff, N.; Goethe, R.; Gruening, P.; Rohde, M.; Kalisz, H.; Smith, H.E.; Valentin-Weigand, P.

    2002-01-01

    The present study was performed to identify stress-induced putative virulence proteins of Streptococcus suis. For this, protein expression patterns of streptococci grown at 32, 37, and 42°C were compared by one- and two-dimensional gel electrophoresis. Temperature shifts from 32 and 37 to 42°C

  5. Streptococci Engage TLR13 on Myeloid Cells in a Site-Specific Fashion.

    Science.gov (United States)

    Kolter, Julia; Feuerstein, Reinhild; Spoeri, Evelyne; Gharun, Kourosh; Elling, Roland; Trieu-Cuot, Patrick; Goldmann, Tobias; Waskow, Claudia; Chen, Zhijian J; Kirschning, Carsten J; Deshmukh, Sachin D; Henneke, Philipp

    2016-03-15

    Streptococci are common human colonizers with a species-specific mucocutaneous distribution. At the same time, they are among the most important and most virulent invasive bacterial pathogens. Thus, site-specific cellular innate immunity, which is predominantly executed by resident and invading myeloid cells, has to be adapted with respect to streptococcal sensing, handling, and response. In this article, we show that TLR13 is the critical mouse macrophage (MΦ) receptor in the response to group B Streptococcus, both in bone marrow-derived MΦs and in mature tissue MΦs, such as those residing in the lamina propria of the colon and the dermis, as well as in microglia. In contrast, TLR13 and its chaperone UNC-93B are dispensable for a potent cytokine response of blood monocytes to group B Streptococcus, although monocytes serve as the key progenitors of intestinal and dermal MΦs. Furthermore, a specific role for TLR13 with respect to MΦ function is supported by the response to staphylococci, where TLR13 and UNC-93B limit the cytokine response in bone marrow-derived MΦs and microglia, but not in dermal MΦs. In summary, TLR13 is a critical and site-specific receptor in the single MΦ response to β-hemolytic streptococci. Copyright © 2016 by The American Association of Immunologists, Inc.

  6. Gene repertoire evolution of Streptococcus pyogenes inferred from phylogenomic analysis with Streptococcus canis and Streptococcus dysgalactiae.

    Directory of Open Access Journals (Sweden)

    Tristan Lefébure

    Full Text Available Streptococcus pyogenes, is an important human pathogen classified within the pyogenic group of streptococci, exclusively adapted to the human host. Our goal was to employ a comparative evolutionary approach to better understand the genomic events concomitant with S. pyogenes human adaptation. As part of ascertaining these events, we sequenced the genome of one of the potential sister species, the agricultural pathogen S. canis, and combined it in a comparative genomics reconciliation analysis with two other closely related species, Streptococcus dysgalactiae and Streptococcus equi, to determine the genes that were gained and lost during S. pyogenes evolution. Genome wide phylogenetic analyses involving 15 Streptococcus species provided convincing support for a clade of S. equi, S. pyogenes, S. dysgalactiae, and S. canis and suggested that the most likely S. pyogenes sister species was S. dysgalactiae. The reconciliation analysis identified 113 genes that were gained on the lineage leading to S. pyogenes. Almost half (46% of these gained genes were phage associated and 14 showed significant matches to experimentally verified bacteria virulence factors. Subsequent to the origin of S. pyogenes, over half of the phage associated genes were involved in 90 different LGT events, mostly involving different strains of S. pyogenes, but with a high proportion involving the horse specific pathogen S. equi subsp. equi, with the directionality almost exclusively (86% in the S. pyogenes to S. equi direction. Streptococcus agalactiae appears to have played an important role in the evolution of S. pyogenes with a high proportion of LGTs originating from this species. Overall the analysis suggests that S. pyogenes adaptation to the human host was achieved in part by (i the integration of new virulence factors (e.g. speB, and the sal locus and (ii the construction of new regulation networks (e.g. rgg, and to some extent speB.

  7. Genomics, evolution, and molecular epidemiology of the Streptococcus bovis/Streptococcus equinus complex (SBSEC).

    Science.gov (United States)

    Jans, Christoph; Meile, Leo; Lacroix, Christophe; Stevens, Marc J A

    2015-07-01

    The Streptococcus bovis/Streptococcus equinus complex (SBSEC) is a group of human and animal derived streptococci that are commensals (rumen and gastrointestinal tract), opportunistic pathogens or food fermentation associates. The classification of SBSEC has undergone massive changes and currently comprises 7 (sub)species grouped into four branches based on sequences identities: the Streptococcus gallolyticus, the Streptococcus equinus, the Streptococcus infantarius and the Streptococcus alactolyticus branch. In animals, SBSEC are causative agents for ruminal acidosis, potentially laminitis and infective endocarditis (IE). In humans, a strong association was established between bacteraemia, IE and colorectal cancer. Especially the SBSEC-species S. gallolyticus subsp. gallolyticus is an emerging pathogen for IE and prosthetic joint infections. S. gallolyticus subsp. pasteurianus and the S. infantarius branch are further associated with biliary and urinary tract infections. Knowledge on pathogenic mechanisms is so far limited to colonization factors such as pili and biofilm formation. Certain strain variants of S. gallolyticus subsp. macedonicus and S. infantarius subsp. infantarius are associated with traditional dairy and plant-based food fermentations and display traits suggesting safety. However, due to their close relationship to virulent strains, their use in food fermentation has to be critically assessed. Additionally, implementing accurate and up-to-date taxonomy is critical to enable appropriate treatment of patients and risk assessment of species and strains via recently developed multilocus sequence typing schemes to enable comparative global epidemiology. Comparative genomics revealed that SBSEC strains harbour genomics islands (GI) that seem acquired from other streptococci by horizontal gene transfer. In case of virulent strains these GI frequently encode putative virulence factors, in strains from food fermentation the GI encode functions that are

  8. Physiological and molecular characterization of genetic competence in Streptococcus sanguinis

    OpenAIRE

    Rodriguez, Alejandro Miguel; Callahan, Jill E.; Fawcett, Paul; Ge, Xiuchun; Xu, Ping; Kitten, Todd

    2011-01-01

    Streptococcus sanguinis is a major component of the oral flora and an important cause of infective endocarditis. Although S. sanguinis is naturally competent, genome sequencing has suggested significant differences in the S. sanguinis competence system relative to those of other streptococci. An S. sanguinis mutant possessing an in-frame deletion in the comC gene, which encodes competence-stimulating peptide (CSP), was created. Addition of synthetic CSP induced competence in this strain. Gene...

  9. Interaction forces between salivary proteins and Streptococcus mutans with and without antigen I/II

    NARCIS (Netherlands)

    Xu, C.P.; Belt-Gritter, van de B.; Dijkstra, R.J.B.; Norde, W.; Mei, van der H.C.; Busscher, H.J.

    2007-01-01

    The antigen I/II family of surface proteins is expressed by oral streptococci, including Streptococcus mutans, and mediates specific binding to, among others, salivary films. The aim of this study was to investigate the interaction forces between salivary proteins and S. mutans with (LT11) and

  10. Identifying protective Streptococcus pyogenes vaccine antigens recognized by both B and T cells in human adults and children

    DEFF Research Database (Denmark)

    Mortensen, Rasmus; Nissen, Thomas Nørrelykke; Fredslund, Sine

    2016-01-01

    No commercial vaccine exists against Group A streptococci (GAS; Streptococcus pyogenes) and only little is known about anti-GAS protective immunity. In our effort to discover new protective vaccine candidates, we selected 21 antigens based on an in silico evaluation. These were all well-conserved......No commercial vaccine exists against Group A streptococci (GAS; Streptococcus pyogenes) and only little is known about anti-GAS protective immunity. In our effort to discover new protective vaccine candidates, we selected 21 antigens based on an in silico evaluation. These were all well...

  11. Identification of genes for small non-coding RNAs that belong to the regulon of the two-component regulatory system CiaRH in Streptococcus

    Directory of Open Access Journals (Sweden)

    Hakenbeck Regine

    2010-11-01

    Full Text Available Abstract Background Post-transcriptional regulation by small RNAs (sRNAs in bacteria is now recognized as a wide-spread regulatory mechanism modulating a variety of physiological responses including virulence. In Streptococcus pneumoniae, an important human pathogen, the first sRNAs to be described were found in the regulon of the CiaRH two-component regulatory system. Five of these sRNAs were detected and designated csRNAs for cia-dependent small RNAs. CiaRH pleiotropically affects β-lactam resistance, autolysis, virulence, and competence development by yet to be defined molecular mechanisms. Since CiaRH is highly conserved among streptococci, it is of interest to determine if csRNAs are also included in the CiaRH regulon in this group of organisms consisting of commensal as well as pathogenic species. Knowledge on the participation of csRNAs in CiaRH-dependent regulatory events will be the key to define the physiological role of this important control system. Results Genes for csRNAs were predicted in streptococcal genomes and data base entries other than S. pneumoniae by searching for CiaR-activated promoters located in intergenic regions that are followed by a transcriptional terminator. 61 different candidate genes were obtained specifying csRNAs ranging in size from 51 to 202 nt. Comparing these genes among each other revealed 40 different csRNA types. All streptococcal genomes harbored csRNA genes, their numbers varying between two and six. To validate these predictions, S. mitis, S. oralis, and S. sanguinis were subjected to csRNA-specific northern blot analysis. In addition, a csRNA gene from S. thermophilus plasmid pST0 introduced into S. pneumoniae was also tested. Each of the csRNAs was detected on these blots and showed the anticipated sizes. Thus, the method applied here is able to predict csRNAs with high precision. Conclusions The results of this study strongly suggest that genes for small non-coding RNAs, csRNAs, are part of

  12. Streptococcal toxic-shock syndrome due to Streptococcus dysgalactiae subspecies equisimilis in breast cancer-related lymphedema: a case report.

    Science.gov (United States)

    Sumazaki, Makoto; Saito, Fumi; Ogata, Hideaki; Yoshida, Miho; Kubota, Yorichika; Magoshi, Syunsuke; Kaneko, Hironori

    2017-07-14

    Breast cancer-related lymphedema often causes cellulitis and is one of the most common complications after breast cancer surgery. Streptococci are the major pathogens underlying such cellulitis. Among the streptococci, the importance of the Lancefield groups C and G is underappreciated; most cases involve Streptococcus dysgalactiae subspecies equisimilis. Despite having a relatively weak toxicity compared with group A streptococci, Streptococcus dysgalactiae subspecies equisimilis is associated with a mortality rate that is as high as that of group A streptococci in cases of invasive infection because Streptococcus dysgalactiae subspecies equisimilis mainly affects elderly individuals who already have various comorbidities. An 83-year-old Japanese woman with breast cancer-related lymphedema in her left upper limb was referred to our hospital with high fever and acute pain with erythema in her left arm. She showed septic shock with disseminated intravascular coagulation. Blood culture showed positive results for Streptococcus dysgalactiae subspecies equisimilis, confirming a diagnosis of streptococcal toxic-shock syndrome. She survived after successful intensive care. To the best of our knowledge, this case represents the first report of Streptococcus dysgalactiae subspecies equisimilis-induced streptococcal toxic-shock syndrome in a patient with breast cancer-related lymphedema. Breast cancer-related lymphedema is a common problem, and we must pay attention to invasive streptococcal soft tissue infections, particularly in elderly patients with chronic disease.

  13. Effect of high pressure on mesophilic lactic fermentation streptococci

    Energy Technology Data Exchange (ETDEWEB)

    Reps, A; Kuzmicka, M; Wisniewska, K [Chair of Food Biotechnology, University of Warmia and Mazury, ul. Heweliusza 1, 10-724 Olsztyn (Poland)], E-mail: arnold.reps@uwm.edu.pl

    2008-07-15

    The research concerned the effect of high pressure on mesophilic lactic fermentation streptococci, present in two cheese-making commercial inocula produced by Christian-Hansen. Water solutions of inocula were pressurized at 50-800 MPa, at room temperature, for 30-120 min. Pressurization at 50-100 MPa slightly increased or reduced the number of lactic streptococci, depending on the inoculum and pressurization time. Pressurization at 200 MPa caused a reduction in the number of streptococci by over 99.9%, whereas the pressure of 400 MPa and above almost completely inactivated streptococci. Pressurization also reduced the dynamics of microorganism growth and acidification, to the degree depending on the pressure.

  14. Beta-haemolytic streptococci in farmed Nile tilapia, Oreochromis niloticus, from Sullana-Piura, Peru

    Directory of Open Access Journals (Sweden)

    Yessica Ortega A

    2017-01-01

    Full Text Available Objective. This investigation aimed to study the presence of Streptococcus spp. in tilapia (Oreochromis niloticus from fish farm located in Sullana-Piura, Peru. Materials and methods. 150 fish with clinical signs of streptococcal disease were sampled, and the bacterium isolation was performed on blood agar, correlated to histopathological lesions description and molecular confirmation by real-time PCR. Results. The necropsy revealed exophthalmia, hyphema, congestion and/or haemorrhagic meninges, ascites, splenomegaly, hepatomegaly and diffuse haemorrhagic zones throughout the body. 102 isolated positives (54 tilapias to Streptococcus spp. were identified in the microbiological analysis (prevalence of 26%, the brain was the organ with the highest percentage of this bacteria (34.31%, and 19 isolates were beta-haemolytic (18.63% with prevalence of 10.12%. Fish beta-haemolytic streptococci presented epicarditis, perisplenitis and chronic meningitis, panophthalmitis, coagulative necrosis of skeletal muscle and granulomas formation. In the confirmatory test by real-time PCR, any positive tilapia to S. iniae was obtained. The results were analysed using a stochastic simulation of beta distribution using @Risk program uncertainty, reporting an average prevalence of 0.66% in sick tilapias. Conclusions. The analysed fishes were positive to bacteria of the genus Streptococcus, which confirms its presence in the fish farm. However, 19 isolates were beta-haemolytic, and the presence of S. iniae was not positive to the limit prevalence of 2.7% in real-time PCR.

  15. Streptococcus suis

    DEFF Research Database (Denmark)

    Poggenborg, René; Gaïni, Shahin; Kjaeldgaard, Poul

    2008-01-01

    Meningitis and spondylodiscitis caused by Streptococcus suis is a rare disease which is contracted by occupational exposure to pigs. We report a 54-y-old pig-farm worker with S. suis meningitis and septicaemia complicated with thoracal and lumbar spine spondylodiscitis. The S. suis strain involved...

  16. MITIE: Simultaneous RNA-Seq-based transcript identification and quantification in multiple samples.

    Science.gov (United States)

    Behr, Jonas; Kahles, André; Zhong, Yi; Sreedharan, Vipin T; Drewe, Philipp; Rätsch, Gunnar

    2013-10-15

    High-throughput sequencing of mRNA (RNA-Seq) has led to tremendous improvements in the detection of expressed genes and reconstruction of RNA transcripts. However, the extensive dynamic range of gene expression, technical limitations and biases, as well as the observed complexity of the transcriptional landscape, pose profound computational challenges for transcriptome reconstruction. We present the novel framework MITIE (Mixed Integer Transcript IdEntification) for simultaneous transcript reconstruction and quantification. We define a likelihood function based on the negative binomial distribution, use a regularization approach to select a few transcripts collectively explaining the observed read data and show how to find the optimal solution using Mixed Integer Programming. MITIE can (i) take advantage of known transcripts, (ii) reconstruct and quantify transcripts simultaneously in multiple samples, and (iii) resolve the location of multi-mapping reads. It is designed for genome- and assembly-based transcriptome reconstruction. We present an extensive study based on realistic simulated RNA-Seq data. When compared with state-of-the-art approaches, MITIE proves to be significantly more sensitive and overall more accurate. Moreover, MITIE yields substantial performance gains when used with multiple samples. We applied our system to 38 Drosophila melanogaster modENCODE RNA-Seq libraries and estimated the sensitivity of reconstructing omitted transcript annotations and the specificity with respect to annotated transcripts. Our results corroborate that a well-motivated objective paired with appropriate optimization techniques lead to significant improvements over the state-of-the-art in transcriptome reconstruction. MITIE is implemented in C++ and is available from http://bioweb.me/mitie under the GPL license.

  17. Rapid identification of pathogenic streptococci isolated from moribund red tilapia (Oreochromis spp.).

    Science.gov (United States)

    Abdelsalam, Mohamed; Elgendy, Mamdouh Y; Shaalan, Mohamed; Moustafa, Mohamed; Fujino, Masayuki

    2017-03-01

    Accurate and rapid identification of bacterial pathogens of fish is essential for the effective treatment and speedy control of infections. Massive mortalities in market-sized red tilapia (Oreochromis spp.) were noticed in mariculture concrete ponds in northern Egypt. Histopathological examination revealed marked congestion in the central vein of the liver with the presence of bacterial aggregates inside the lumen and in the vicinity of the central vein. A total of 12 isolates of streptococci were obtained from the moribund fish. This study documented the ability of the MicroSeq 500 16S bacterial sequencing method to accurately identify Streptococcus agalactiae and S. dysgalactiae mixed infections from moribund red tilapia that were difficult to be recognised by the commercial biochemical systems. The continuously decreasing cost of the sequencing technique should encourage its application in routine diagnostic procedures.

  18. Aciduricity and acid tolerance mechanisms of Streptococcus anginosus.

    Science.gov (United States)

    Sasaki, Minoru; Kodama, Yoshitoyo; Shimoyama, Yu; Ishikawa, Taichi; Kimura, Shigenobu

    2018-04-17

    Although Streptococcus anginosus constitutes a proportion of the normal flora of the gastrointestinal and genital tracts, and the oral cavity, it has been reported that S. anginosus infection could be closely associated with abscesses at various body sites, infective endocarditis, and upper gastrointestinal cancers. The colonization in an acidic environment due to the aciduricity of S. anginosus could be the etiology of the systemic infection of the bacteria. To elucidate the aciduricity and acid tolerance mechanisms of the microbe, we examined the viability and growth of S. anginosus under acidic conditions. The viabilities of S. anginosus NCTC 10713 and Streptococcus mutans ATCC 25175 at pH 4.0 showed as being markedly higher than those of Streptococcus sanguinis ATCC 10556, Streptococcus gordonii ATCC 10558, and Streptococcus mitis ATCC 49456; however, the viability was partially inhibited by dicyclohexylcarbodiimide, an H + -ATPase inhibitor, suggesting that H + -ATPase could play a role in the viability of S. anginosus under acidic conditions. In addition, S. anginosus NCTC 10713 could grow at pH 5.0 and showed a marked arginine deiminase (ADI) activity, unlike its ΔarcA mutant, deficient in the gene encoding ADI, and other streptococcal species, which indicated that ADI could also be associated with aciduricity. These results suggest that S. anginosus has significant aciduric properties, which can be attributed to these enzyme activities.

  19. Rare and unusual isolates of viridans streptococci from the human oral cavity

    Directory of Open Access Journals (Sweden)

    Shree Dhotre

    2016-01-01

    Full Text Available Context: The genus Streptococcus consists of more than 65 species. The taxonomic classification of these members is not well-defined. Among the viridans group streptococci (VGS, there are major taxonomic changes by the addition of many new species; whereas, most of the new strains are of animal origin and only a few have been reported to be isolated from humans. Rare and unusual species of VGS such as Streptococcus thoraltensis, S. pluranimalium and S. hyointestinalis are normally associated with different animals. Their isolation from human being is not yet reported. Aim: To find out the rare and unusual species of viridans group streptococci from human oral cavity. Settings and Design: A case-controlled study carried out at hospital-based dental services in a tertiary care hospital. Materials and Methods: Subgingival plaque samples of the tooth were collected from 80 patients (34 with periodontitis and 46 without periodontitis undergoing tooth extraction. Cultures were subcultured onto special media such as Tryptone Soya blood Agar supplemented with strepto supplement and Mutans-Sanguis Agar. Identification of strains and antimicrobial susceptibilities were measured as minimum inhibitory concentration using Vitek 2 (BioMérieux, Paris, France automated system. Results: We have identified three strains of VGS - S. thoraltensis, S. pluranimalium and S. hyointestinalis from subgingival plaque samples from patients with periodontitis. S. thoraltensis and S. pluranimalium were found to be resistant to most of the antibiotics. Conclusions: To the best of our knowledge, this is the first report of isolation of these rare and unusual strains from the human oral cavity.

  20. Synergistic streptococcal phage λSA2 and B30 endolysins kill streptococci in cow milk and in a mouse model of mastitis.

    Science.gov (United States)

    Schmelcher, Mathias; Powell, Anne M; Camp, Mary J; Pohl, Calvin S; Donovan, David M

    2015-10-01

    Bovine mastitis results in billion dollar losses annually in the USA alone. Streptococci are among the most relevant causative agents of this disease. Conventional antibiotic therapy is often unsuccessful and contributes to development of antibiotic resistance. Bacteriophage endolysins represent a new class of antimicrobials against these bacteria. In this work, we characterized the endolysins (lysins) of the streptococcal phages λSA2 and B30 and evaluated their potential as anti-mastitis agents. When tested in vitro against live streptococci, both enzymes exhibited near-optimum lytic activities at ionic strengths, pH, and Ca(2+) concentrations consistent with cow milk. When tested in combination in a checkerboard assay, the lysins were found to exhibit strong synergy. The λSA2 lysin displayed high activity in milk against Streptococcus dysgalactiae (reduction of CFU/ml by 3.5 log units at 100 μg/ml), Streptococcus agalactiae (2 log), and Streptococcus uberis (4 log), whereas the B30 lysin was less effective. In a mouse model of bovine mastitis, both enzymes significantly reduced intramammary concentrations of all three streptococcal species (except for B30 vs. S. dysgalactiae), and the effects on mammary gland wet weights and TNFα concentrations were consistent with these findings. Unexpectedly, the synergistic effect determined for the two enzymes in vitro was not observed in the mouse model. Overall, our results illustrate the potential of endolysins for treatment of Streptococcus-induced bovine mastitis.

  1. Invasieve infecties door beta-haemolytische Streptokokken Lancefield Groep A (Streptococcus pyogenes, GAS) in Nederland, 1992-1993

    NARCIS (Netherlands)

    Schellekens JFP; Schouls LM; van Silfhout A; Elzenaar CP; Brunings HA; Blokpoel MCJ; Top J; van Leeuwen WJ; LBA; MMB

    1994-01-01

    In recent years an increase of severe invasive infections and toxic shock syndrome (TSS) with beta-haemolytic Group A streptococci (Streptococcus pyogenes, GAS) has been reported from North-America and North-Western Europe. In the spring of 1992 several reports of cases suggested that this epidemic

  2. BIOSURFACTANT PRODUCTION BY THERMOPHILIC DAIRY STREPTOCOCCI

    NARCIS (Netherlands)

    BUSSCHER, HJ; NEU, TR; VANDERMEI, HC

    Biosurfactant production of eight Streptococcus thermophilus strains, isolated from heat exchanger plates in the downstream side of the regenerator section of pasteurizers in the dairy industry has been measured using axisymmetric drop shape analysis by profile (ADSA-P). Strains were grown in M17

  3. Transformation of group A streptococci by electroporation

    NARCIS (Netherlands)

    Suvorov, Alexander; Kok, Jan; Venema, Gerhardus

    1988-01-01

    The introduction, via electroporation, of free plasmid DNA into three strains of Streptococcus pyogenes is described. The method is very simple and rapid and efficiencies vary from 1 × 10^3 to 4 × 10^4 per µg of DNA. The method was also used to introduce an integrative plasmid and transformants were

  4. Molecular characterization of the presence of Eubacterium spp and Streptococcus spp in endodontic infections.

    Science.gov (United States)

    Fouad, A F; Kum, K-Y; Clawson, M L; Barry, J; Abenoja, C; Zhu, Q; Caimano, M; Radolf, J D

    2003-08-01

    Eubacterium spp. and Streptococcus spp. are virulent, commonly identified microorganisms in endodontic infections. The purpose of this study was to use molecular methods to identify these organisms in 22 infected root canals that include eight cases with preoperative clinical symptoms and five cases with a history of diabetes mellitus. The presence of Streptococcus spp. and Eubacterium spp. was examined using two sets of PCR primers specific with multiple species within the respective genera. Positive specimens had their PCR products sequenced and phylogenetically analyzed to identify the specific species. Sixteen specimens (73%) contained Eubacterium spp. and nine (41%) were positive for Streptococcus spp. Eubacterium infirmum was the most prevalent Eubacterium sp. This organism was significantly associated with a history of diabetes (OR = 9.6; P = 0.04). Streptococcus anginosus was the most common Streptococcus sp., but neither it nor any of the other streptococci were significantly associated with the clinical parameters evaluated.

  5. The prevalence and antibiotic sensitivity of oral Viridans streptococci in healthy children and children with disabilities in Kuwait.

    Science.gov (United States)

    Salako, Nathanael O; Rotimi, Vincent; Philip, Leeba; Haidar, Hussien A; Hamdan, Hussien M

    2007-01-01

    The purpose of this study was to compare the antibiotic susceptibility profiles of Viridans streptococci (VS) isolated from the oral cavity of healthy children and children with disabilities in Kuwait. Plaque samples were collected from the tooth and tongue surfaces of 102 healthy children and 102 children who were intellectually disabled and institutionalized. The resistance to seven antibiotics (amoxicillin, cephalothin, clindamycin, erythromycin, penicillin G, tetracycline, and vancomycin) was tested. A total of 330 (44.5%) VS were isolated from the children who were healthy and 411 (55.5%) from children with disabilities. The most common isolates were S. salivarius (27.3%) in healthy children; S. sanguis (22.6%) was predominant among children who were disabled. S. mutans was found in 12.1% of the healthy children and in 16.5% of the children who were disabled. The combined percentage of resistant strains (healthy and disabled) was found to be highest with amoxicillin (43%) and lowest with vancomycin (12%). S. sanguis, S. mitis and S. oralis were more resistant in healthy children (45%, 56%, and 55% respectively) than in children with disabilities (40%, 47% and 47% respectively). S. mutans was the least resistant species to all antibiotics in both groups of children. About 56% of all streptococci isolated from both groups were resistant to at least one of the antibiotics tested. The data showed that there was a difference in the level of resistance of oral VS isolated from healthy children and children with disabilities to some antibiotics commonly used in dentistry.

  6. Amoxicillin-resistant oral streptococci identified in dental plaque specimens from healthy Japanese adults.

    Science.gov (United States)

    Masuda, Katsuhiko; Nemoto, Hirotoshi; Nakano, Kazuhiko; Naka, Shuhei; Nomura, Ryota; Ooshima, Takashi

    2012-05-01

    Infective endocarditis (IE) is known to be a life-threatening disease and invasive dental procedures are considered to be important factors. Oral amoxicillin (AMPC) is widely used for prophylaxis in patients with heart disorders who are at risk for IE. However, there is only limited information regarding the inhibition of oral bacteria by AMPC. Dental plaque specimens were obtained from 120 healthy Japanese adult subjects, then diluted and streaked onto selective medium for oral streptococci. The minimum inhibitory concentration (MIC) of AMPC was evaluated using a macro-dilution method by Clinical Laboratory Standard Institute (2006). Seven strains with an MIC of AMPC of 16μg/mL or more were isolated from 5 subjects. The bacterial species were confirmed by sequence analysis of 16S rRNA from each strain, which demonstrated that most were Streptococcus sanguinis, followed by Streptococcus oralis. Dental plaque specimens collected from these 5 subjects again after an interval of 2-3 months possessed no strains with an MIC of AMPC of 16μg/mL or more. These findings suggest that strains with a high MIC of AMPC are present in the oral cavities of Japanese adults, though they may be transient rather than inhabitants. Copyright © 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  7. Current status of taxonomic groups of oral streptococci in endocarditis. Can virulence factors discriminate between endocarditis and non-endocarditis strains?

    DEFF Research Database (Denmark)

    Larsen, Tove; Fiehn, Nils-Erik; Gutschik, Ernö

    1999-01-01

    streptococcal isolates from the oral cavities of periodontal patients without endocarditis. Subsequently, surface hydrophobicity was assessed by hydrophobic interaction chromatography, production of extracellular dextran was determined by precipitation, and non-specific proteolytic activity was evaluated......OBJECTIVE: Infective endocarditis is frequently caused by oral streptococci, especially Streptococcus sanguis. In this group, many strains have recently been reclassified on the basis of new taxonomic schemes. The purpose of this study was to classify oral streptococci from patients with infective...... and non-endocarditis isolates. CONCLUSIONS: The present study showed that infective endocarditis may be caused by a variety of oral streptococcal species. The possible virulence factors investigated were found in the same proportions in endocarditis and non-endocarditis isolates, and thus did not seem...

  8. Salivary secretory IgA, pH, flow rates, mutans streptococci and Candida in children with rampant caries.

    Science.gov (United States)

    Thaweboon, Sroisiri; Thaweboon, Boonyanit; Nakornchai, Siriruk; Jitmaitree, Sukritta

    2008-09-01

    The aim of this study was to determine the levels of secretory IgA (SIgA), pH, flow rates, mutans streptococci (MS) and Candida in saliva of children with rampant caries compared to those caries-free. Thirty children (age 62-123 months) were enrolled and divided into two groups: Group I, children with rampant caries, Group II, caries-free children. The average salivary flow rate was measured from the volume yielded within 5 minutes and the pH was determined using a pH-electrode. Measurement of SIgA was performed using an immunoassay kit. The levels of MS and Candida were determined by culture on Mitis-Salivarius Bacitracin agar and Sabouraud dextrose agar. It was found that children with rampant caries presented with significantly higher levels of salivary SIgA, MS and Candida. However, the mean values for salivary flow rates and pH were similar between the groups. The results reveal that children with rampant caries had significantly higher levels of SIgA, MS and Candida in their oral cavities. This finding tends to support the hypothesis that higher levels of salivary SIgA may reflect a past exposure of the host to cariogenic microorganisms.

  9. Oral streptococci utilize a Siglec-like domain of serine-rich repeat adhesins to preferentially target platelet sialoglycans in human blood.

    Directory of Open Access Journals (Sweden)

    Lingquan Deng

    2014-12-01

    Full Text Available Damaged cardiac valves attract blood-borne bacteria, and infective endocarditis is often caused by viridans group streptococci. While such bacteria use multiple adhesins to maintain their normal oral commensal state, recognition of platelet sialoglycans provides an intermediary for binding to damaged valvular endocardium. We use a customized sialoglycan microarray to explore the varied binding properties of phylogenetically related serine-rich repeat adhesins, the GspB, Hsa, and SrpA homologs from Streptococcus gordonii and Streptococcus sanguinis species, which belong to a highly conserved family of glycoproteins that contribute to virulence for a broad range of Gram-positive pathogens. Binding profiles of recombinant soluble homologs containing novel sialic acid-recognizing Siglec-like domains correlate well with binding of corresponding whole bacteria to arrays. These bacteria show multiple modes of glycan, protein, or divalent cation-dependent binding to synthetic glycoconjugates and isolated glycoproteins in vitro. However, endogenous asialoglycan-recognizing clearance receptors are known to ensure that only fully sialylated glycans dominate in the endovascular system, wherein we find these particular streptococci become primarily dependent on their Siglec-like adhesins for glycan-mediated recognition events. Remarkably, despite an excess of alternate sialoglycan ligands in cellular and soluble blood components, these adhesins selectively target intact bacteria to sialylated ligands on platelets, within human whole blood. These preferred interactions are inhibited by corresponding recombinant soluble adhesins, which also preferentially recognize platelets. Our data indicate that circulating platelets may act as inadvertent Trojan horse carriers of oral streptococci to the site of damaged endocardium, and provide an explanation why it is that among innumerable microbes that gain occasional access to the bloodstream, certain viridans group

  10. Present status of research activities relating global warming problems in Japan (mainly MITI and relating organizations)

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, O.

    1993-12-31

    Japanese government has issued action program so called {open_quotes}Action Program to Arrest Global Warming{close_quotes} for preventing global warming at Oct., 1990. According to the program, CO{sub 2} emission should be stabilized on a per capita basis in the year 2000 and beyond at about same level as in 2000 by introducing several methods such as energy conservation, improvement of energy using efficiency, expanding use of renewable energy and so on. The basic concept, target and methods are summarized. At the same time, MITI published so called {open_quotes}New Earth 21{close_quotes} project which aims remedying the earth environment modified by human activities since industrial innovation began at about 200 years ago in coming 100 years. This plan proposed yearly step of research development of technology for mitigating CO{sub 2} emission. According to the MITI`s plan, 15 institutions belonging to AIST have carrying research for developing technology of reducing emission of CO{sub 2} and other greenhouse gases, with cooperation of other research organizations such as RITE (research Institute of Innovative Technology for Earth) and NEDO (New Energy and Industrial Technology Developing Organization). Time schedule of the research development by The New Earth 21 project is summarized in Table 2. Now, in Japan, many national institutions and universities, research works relating reduction and mitigation of GHG are carried out according to this guideline.

  11. Transfection of Eimeria mitis with yellow fluorescent protein as reporter and the endogenous development of the transgenic parasite.

    Directory of Open Access Journals (Sweden)

    Mei Qin

    Full Text Available BACKGROUND: Advancements have been made in the genetic manipulation of apicomplexan parasites. Both the in vitro transient and in vivo stable transfection of Eimeria tenella have been developed successfully. Herein, we report the transient and stable transfection of Eimeria mitis. METHODS AND FINDINGS: Sporozoites of E. mitis transfected with enhanced yellow fluorescent protein (EYFP expression plasmid were inoculated into chickens via the cloacal route. The recovered fluorescent oocysts were sorted by fluorescence activated cell sorting (FACS and then passaged 6 generations successively in chickens. The resulting population was analyzed by genome walking and Western blot. The endogenous development of the transgenic E. mitis was observed and its reproduction potential was tested. The stable transfection of E. mitis was developed. Genome walking confirmed the random integration of plasmid DNA into the genome; while Western blot analysis demonstrated the expression of foreign proteins. Constitutive expression of EYFP was observed in all stages of merogony, gametogony and sporogony. The peak of the transgenic oocyst output was delayed by 24 h and the total oocyst reproduction was reduced by 7-fold when compared to the parental strain. CONCLUSION: Stable transfection of E. mitis was successfully developed. The expression of foreign antigens in the transgenic parasites will facilitate the development of transgenic E. mitis as a vaccine vector.

  12. Genome of the opportunistic pathogen Streptococcus sanguinis.

    Science.gov (United States)

    Xu, Ping; Alves, Joao M; Kitten, Todd; Brown, Arunsri; Chen, Zhenming; Ozaki, Luiz S; Manque, Patricio; Ge, Xiuchun; Serrano, Myrna G; Puiu, Daniela; Hendricks, Stephanie; Wang, Yingping; Chaplin, Michael D; Akan, Doruk; Paik, Sehmi; Peterson, Darrell L; Macrina, Francis L; Buck, Gregory A

    2007-04-01

    The genome of Streptococcus sanguinis is a circular DNA molecule consisting of 2,388,435 bp and is 177 to 590 kb larger than the other 21 streptococcal genomes that have been sequenced. The G+C content of the S. sanguinis genome is 43.4%, which is considerably higher than the G+C contents of other streptococci. The genome encodes 2,274 predicted proteins, 61 tRNAs, and four rRNA operons. A 70-kb region encoding pathways for vitamin B(12) biosynthesis and degradation of ethanolamine and propanediol was apparently acquired by horizontal gene transfer. The gene complement suggests new hypotheses for the pathogenesis and virulence of S. sanguinis and differs from the gene complements of other pathogenic and nonpathogenic streptococci. In particular, S. sanguinis possesses a remarkable abundance of putative surface proteins, which may permit it to be a primary colonizer of the oral cavity and agent of streptococcal endocarditis and infection in neutropenic patients.

  13. Comprehensive Evaluation of Streptococcus sanguinis Cell Wall-Anchored Proteins in Early Infective Endocarditis▿ †

    OpenAIRE

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L.; Wu, Hui; Kitten, Todd

    2009-01-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) a...

  14. Viable group A streptococci in macrophages during acute soft tissue infection.

    Directory of Open Access Journals (Sweden)

    Pontus Thulin

    2006-03-01

    Full Text Available Group A streptococcal severe soft tissue infections, such as necrotizing fasciitis, are rapidly progressive infections associated with high mortality. Group A streptococcus is typically considered an extracellular pathogen, but has been shown to reside intracellularly in host cells.We characterized in vivo interactions between group A streptococci (GAS and cells involved in innate immune responses, using human biopsies (n = 70 collected from 17 patients with soft tissue infections. Immunostaining and in situ image analysis revealed high amounts of bacteria in the biopsies, even in those collected after prolonged antibiotic therapy. Viability of the streptococci was assessed by use of a bacterial viability stain, which demonstrated viable bacteria in 74% of the biopsies. GAS were present both extracellularly and intracellularly within phagocytic cells, primarily within macrophages. Intracellular GAS were predominantly noted in biopsies from newly involved tissue characterized by lower inflammation and bacterial load, whereas purely extracellular GAS or a combination of intra- and extracellular GAS dominated in severely inflamed tissue. The latter tissue was also associated with a significantly increased amount of the cysteine protease streptococcal pyrogenic exotoxin SpeB. In vitro studies confirmed that macrophages serve as reservoirs for viable GAS, and infection with a speB-deletion mutant produced significantly lower frequencies of cells with viable GAS following infection as compared to the wild-type bacteria.This is the first study to demonstrate that GAS survive intracellularly in macrophages during acute invasive infections. This intracellular presence may have evolved as a mechanism to avoid antibiotic eradication, which may explain our finding that high bacterial load is present even in tissue collected after prolonged intravenous antibiotic therapy. This new insight into the pathogenesis of streptococcal soft tissue infections

  15. Viable Group A Streptococci in Macrophages during Acute Soft Tissue Infection.

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available BACKGROUND: Group A streptococcal severe soft tissue infections, such as necrotizing fasciitis, are rapidly progressive infections associated with high mortality. Group A streptococcus is typically considered an extracellular pathogen, but has been shown to reside intracellularly in host cells. METHODS AND FINDINGS: We characterized in vivo interactions between group A streptococci (GAS and cells involved in innate immune responses, using human biopsies (n = 70 collected from 17 patients with soft tissue infections. Immunostaining and in situ image analysis revealed high amounts of bacteria in the biopsies, even in those collected after prolonged antibiotic therapy. Viability of the streptococci was assessed by use of a bacterial viability stain, which demonstrated viable bacteria in 74% of the biopsies. GAS were present both extracellularly and intracellularly within phagocytic cells, primarily within macrophages. Intracellular GAS were predominantly noted in biopsies from newly involved tissue characterized by lower inflammation and bacterial load, whereas purely extracellular GAS or a combination of intra- and extracellular GAS dominated in severely inflamed tissue. The latter tissue was also associated with a significantly increased amount of the cysteine protease streptococcal pyrogenic exotoxin SpeB. In vitro studies confirmed that macrophages serve as reservoirs for viable GAS, and infection with a speB-deletion mutant produced significantly lower frequencies of cells with viable GAS following infection as compared to the wild-type bacteria. CONCLUSIONS: This is the first study to demonstrate that GAS survive intracellularly in macrophages during acute invasive infections. This intracellular presence may have evolved as a mechanism to avoid antibiotic eradication, which may explain our finding that high bacterial load is present even in tissue collected after prolonged intravenous antibiotic therapy. This new insight into the pathogenesis

  16. Physiologic actions of zinc related to inhibition of acid and alkali production by oral streptococci in suspensions and biofilms.

    Science.gov (United States)

    Phan, T-N; Buckner, T; Sheng, J; Baldeck, J D; Marquis, R E

    2004-02-01

    Zinc is a known inhibitor of acid production by mutans streptococci. Our primary objective was to extend current knowledge of the physiologic bases for this inhibition and also for zinc inhibition of alkali production by Streptococcus rattus FA-1 and Streptococcus salivarius ATCC 13419. Zinc at concentrations as low as 0.01-0.1 mm not only inhibited acid production by cells of Streptococcus mutans GS-5 in suspensions or in biofilms but also sensitized glycolysis by intact cells to acidification. Zinc reversibly inhibited the F-ATPase of permeabilized cells of S. mutans with a 50% inhibitory concentration of about 1 mm for cells in suspensions. Zinc reversibly inhibited the phosphoenolpyruvate: sugar phosphotransferase system with 50% inhibition at about 0.3 mm ZnSO4, or about half that concentration when the zinc-citrate chelate was used. The reversibility of these inhibitory actions of zinc correlates with findings that it is mainly bacteriostatic rather than bactericidal. Zinc inhibited alkali production from arginine or urea and was a potent enzyme inhibitor for arginine deiminase of S. rattus FA-1 and for urease of S. salivarius. In addition, zinc citrate at high levels of 10-20 mm was weakly bactericidal.

  17. Children with severe early childhood caries: streptococci genetic strains within carious and white spot lesions.

    Science.gov (United States)

    Gilbert, Kenneth; Joseph, Raphael; Vo, Alex; Patel, Trusha; Chaudhry, Samiya; Nguyen, Uyen; Trevor, Amy; Robinson, Erica; Campbell, Margaret; McLennan, John; Houran, Farielle; Wong, Tristan; Flann, Kendra; Wages, Melissa; Palmer, Elizabeth A; Peterson, John; Engle, John; Maier, Tom; Machida, Curtis A

    2014-01-01

    Mutans streptococci (MS) are one of the major microbiological determinants of dental caries. The objectives of this study are to identify distinct MS and non-MS streptococci strains that are located at carious sites and non-carious enamel surfaces in children with severe early childhood caries (S-ECC), and assess if cariogenic MS and non-cariogenic streptococci might independently exist as primary bacterial strains on distinct sites within the dentition of individual children. Dental plaque from children (N=20; aged 3-6) with S-ECC was collected from carious lesions (CLs), white spot lesions (WSLs) and non-carious enamel surfaces. Streptococcal isolates (N=10-20) from each site were subjected to polymerase chain reaction (PCR) to identify MS, and arbitrarily primed-PCR for assignment of genetic strains. Primary strains were identified as ≥50% of the total isolates surveyed at any site. In several cases, strains were characterized for acidurity using ATP-driven bioluminescence and subjected to PCR-determination of potential MS virulence products. Identification of non-MS was determined by 16S rRNA gene sequencing. Sixty-four independent MS or non-MS streptococcal strains were identified. All children contained 1-6 strains. In many patients (N=11), single primary MS strains were identified throughout the dentition. In other patients (N=4), primary MS strains were identified within CLs that were distinct from primary strains found on enamel. Streptococcus gordonii strains were identified as primary strains on enamel or WSLs in four children, and in general were less aciduric than MS strains. Many children with S-ECC contained only a single primary MS strain that was present in both carious and non-carious sites. In some cases, MS and non-cariogenic S. gordonii strains were found to independently exist as dominant strains at different locations within the dentition of individual children, and the aciduric potential of these strains may influence susceptibility in the

  18. Children with severe early childhood caries: streptococci genetic strains within carious and white spot lesions

    Directory of Open Access Journals (Sweden)

    Kenneth Gilbert

    2014-10-01

    Full Text Available Background and objectives: Mutans streptococci (MS are one of the major microbiological determinants of dental caries. The objectives of this study are to identify distinct MS and non-MS streptococci strains that are located at carious sites and non-carious enamel surfaces in children with severe early childhood caries (S-ECC, and assess if cariogenic MS and non-cariogenic streptococci might independently exist as primary bacterial strains on distinct sites within the dentition of individual children. Design: Dental plaque from children (N=20; aged 3–6 with S-ECC was collected from carious lesions (CLs, white spot lesions (WSLs and non-carious enamel surfaces. Streptococcal isolates (N=10–20 from each site were subjected to polymerase chain reaction (PCR to identify MS, and arbitrarily primed-PCR for assignment of genetic strains. Primary strains were identified as ≥50% of the total isolates surveyed at any site. In several cases, strains were characterized for acidurity using ATP-driven bioluminescence and subjected to PCR-determination of potential MS virulence products. Identification of non-MS was determined by 16S rRNA gene sequencing. Results: Sixty-four independent MS or non-MS streptococcal strains were identified. All children contained 1–6 strains. In many patients (N=11, single primary MS strains were identified throughout the dentition. In other patients (N=4, primary MS strains were identified within CLs that were distinct from primary strains found on enamel. Streptococcus gordonii strains were identified as primary strains on enamel or WSLs in four children, and in general were less aciduric than MS strains. Conclusions: Many children with S-ECC contained only a single primary MS strain that was present in both carious and non-carious sites. In some cases, MS and non-cariogenic S. gordonii strains were found to independently exist as dominant strains at different locations within the dentition of individual children, and

  19. Identification of proteins in Streptococcus pneumoniae by reverse vaccinology and genetic diversity of these proteins in clinical isolates.

    Science.gov (United States)

    Argondizzo, Ana Paula Corrêa; da Mota, Fabio Faria; Pestana, Cristiane Pinheiro; Reis, Joice Neves; de Miranda, Antonio Basílio; Galler, Ricardo; Medeiros, Marco Alberto

    2015-02-01

    Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. Virulence-associated proteins common and conserved among all capsular types now represent the best strategy to combat pneumococcal infections. Our aim was to identify conserved targets in pneumococci that showed positive prediction for lipoprotein and extracellular subcellular location using bioinformatics programs and verify the distribution and the degree of conservation of these targets in pneumococci. These targets can be considered potential vaccine candidate to be evaluated in the future. A set of 13 targets were analyzed and confirmed the presence in all pneumococci tested. These 13 genes were highly conserved showing around >96 % of amino acid and nucleotide identity, but they were also present and show high identity in the closely related species Streptococcus mitis, Streptococcus oralis, and Streptococcus pseudopneumoniae. S. oralis clusters away from S. pneumoniae, while S. pseudopneumoniae and S. mitis cluster closer. The divergence between the selected targets was too small to be observed consistently in phylogenetic groups between the analyzed genomes of S. pneumoniae. The proteins analyzed fulfill two of the initial criteria of a vaccine candidate: targets are present in a variety of different pneumococci strains including different serotypes and are conserved among the samples evaluated.

  20. Group B streptococcus - pregnancy

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000511.htm Group B streptococcus - pregnancy To use the sharing features on this page, please enable JavaScript. Group B streptococcus (GBS) is a type of bacteria that some ...

  1. Natural history of Streptococcus sanguinis in the oral cavity of infants: evidence for a discrete window of infectivity.

    Science.gov (United States)

    Caufield, P W; Dasanayake, A P; Li, Y; Pan, Y; Hsu, J; Hardin, J M

    2000-07-01

    The heterogeneous group of oral bacteria within the sanguinis (sanguis) streptococci comprise members of the indigenous biota of the human oral cavity. While the association of Streptococcus sanguinis with bacterial endocarditis is well described in the literature, S. sanguinis is thought to play a benign, if not a beneficial, role in the oral cavity. Little is known, however, about the natural history of S. sanguinis and its specific relationship with other oral bacteria. As part of a longitudinal study concerning the transmission and acquisition of oral bacteria within mother-infant pairs, we examined the initial acquisition of S. sanguinis and described its colonization relative to tooth emergence and its proportions in plaque and saliva as a function of other biological events, including subsequent colonization with mutans streptococci. A second cohort of infants was recruited to define the taxonomic affiliation of S. sanguinis. We found that the colonization of the S. sanguinis occurs during a discrete "window of infectivity" at a median age of 9 months in the infants. Its colonization is tooth dependent and correlated to the time of tooth emergence; its proportions in saliva increase as new teeth emerge. In addition, early colonization of S. sanguinis and its elevated levels in the oral cavity were correlated to a significant delay in the colonization of mutans streptococci. Underpinning this apparent antagonism between S. sanguinis and mutans streptococci is the observation that after mutans streptococci colonize the infant, the levels of S. sanguinis decrease. Children who do not harbor detectable levels of mutans streptococci have significantly higher levels of S. sanguinis in their saliva than do children colonized with mutans streptococci. Collectively, these findings suggest that the colonization of S. sanguinis may influence the subsequent colonization of mutans streptococci, and this in turn may suggest several ecological approaches toward controlling

  2. Pathogenicity of Virulent Species of Group C Streptococci in Human

    Directory of Open Access Journals (Sweden)

    Marta Kłos

    2017-01-01

    Full Text Available Group C streptococci (GCS are livestock pathogens and they often cause zoonotic diseases in humans. They are Gram-positive, in mostly β-hemolytic and facultative anaerobes. Because of their close evolutionary kinship with group A streptococci (GAS, GCS share many common virulence factors with GAS and cause a similar range of diseases. Due to the exchange of genetic material with GAS, GCS belong to bacteria that are difficult to be distinguished from group A streptococci; GCS are often treated in microbiological diagnostics as contamination of the culture. This report focuses mainly on the pathogenicity of virulent species of GCS and their association with human diseases. The condition that is most frequently quoted is pharyngitis. In this paper, the virulence factors have also been mentioned and an interesting link has been made between GCS and the pathogenesis of rheumatic diseases among the native people of India and Aboriginal populations.

  3. Penicillin tolerance among Beta-hemolytic streptococci and production of the group carbohydrates, hemolysins, hyaluronidases and deoxyribonucleases

    Directory of Open Access Journals (Sweden)

    Cássia C. Avelino

    1995-08-01

    Full Text Available Penicillin tolerance among 67 strains of beta-hemolytic streptococci was examined by determining the ratio of the minimal bactericidal concentration to the minimal inhibitory concentration as 32 or greater. Tolerance was demonstrated in 15 group A strains and in 11,7, and 4 of groups B, C and G, respectively. Thereafter the effects of a subminimal inhibitory concentration (1/2MIC of penicillin on the bacterial products of four tolerant and four nontolerant strains (two of each Lancefield group were analyzed and compared. The antibiotic caused a marked increase in the expression of the group carbo-hydrates for strains of group B. Penicillin was found to reduce the cell-bound hemolysin activities of the four tolerant strains and to increase the activity of the other (free form of nontolerant groups A, C and G hemolysins. Penicillin caused an increase in the extracellular hyaluronidase activities of one group A and groups B, C and G streptococci. With added antibiotic the production of deoxyribonuclease by tolerant groups A, C and G was greatly enhanced and that of the group B streptococcus was arrested.

  4. Confocal Raman Microspectroscopy of Oral Streptococci

    Science.gov (United States)

    Beier, Brooke D.

    Raman spectroscopy has been used in a variety of applications throughout the field of biomedical optics. It has the ability to acquire chemically-specific information in a non-invasive manner, without the need for exogenous markers. This makes it useful in the identification of bacterial species, as well as in the study of tissues and other cells. In this work, a species identification model has been created in order to discriminate between the oral bacterial species Streptococcus sanguinis and Streptococcus mutans. These are two of the most prevalent species within the human mouth and their relative concentrations can be an indicator of a patient's oral health and risk of tooth decay. They are predominantly found within plaque on the tooth's surface. To study a simplified model for dental plaque, we have examined S. sanguinis and S. mutans grown in biofilm forms. Raman spectroscopy has been implemented here through a confocal microscope. The optical system has been equipped with computationally controlled stages to allow for automated scanning, including autofocusing to probe a consistent depth within a sample. A spectrum has been acquired from each position within a scan and sent for spectral preprocessing before being submitted for species identification. This preprocessing includes an algorithm that has been developed to remove fluorescence features from known contaminants within the confocal volume, to include signal from a fluorescent substrate. Species classification has been accomplished using a principal component score-fed logistic regression model constructed from a variety of biofilm samples that have been transferred and allowed to dry, as might occur with the study of plaque samples. This binary classification model has been validated on other samples with identical preparations. The model has also been transferred to determine the species of hydrated biofilms studied in situ. Artificially mixed biofilms have been examined to test the spatial

  5. A bacteriophage endolysin that eliminates intracellular streptococci

    Science.gov (United States)

    Shen, Yang; Barros, Marilia; Vennemann, Tarek; Gallagher, D Travis; Yin, Yizhou; Linden, Sara B; Heselpoth, Ryan D; Spencer, Dennis J; Donovan, David M; Moult, John; Fischetti, Vincent A; Heinrich, Frank; Lösche, Mathias; Nelson, Daniel C

    2016-01-01

    PlyC, a bacteriophage-encoded endolysin, lyses Streptococcus pyogenes (Spy) on contact. Here, we demonstrate that PlyC is a potent agent for controlling intracellular Spy that often underlies refractory infections. We show that the PlyC holoenzyme, mediated by its PlyCB subunit, crosses epithelial cell membranes and clears intracellular Spy in a dose-dependent manner. Quantitative studies using model membranes establish that PlyCB interacts strongly with phosphatidylserine (PS), whereas its interaction with other lipids is weak, suggesting specificity for PS as its cellular receptor. Neutron reflection further substantiates that PlyC penetrates bilayers above a PS threshold concentration. Crystallography and docking studies identify key residues that mediate PlyCB–PS interactions, which are validated by site-directed mutagenesis. This is the first report that a native endolysin can traverse epithelial membranes, thus substantiating the potential of PlyC as an antimicrobial for Spy in the extracellular and intracellular milieu and as a scaffold for engineering other functionalities. DOI: http://dx.doi.org/10.7554/eLife.13152.001 PMID:26978792

  6. Considerazioni sulla receptio legis alla luce del m.p. Mitis Iudex Dominus Iesus

    Directory of Open Access Journals (Sweden)

    Maria Chiara Ruscazio

    2018-03-01

    ABSTRACT: Reception of law can be described as the process by which the recipients of a canonical law verify its reasonableness. This process appears mostly in the material observance of the law. The essay examines firstly the theological and ecclesiological legitimacy of reception, and then it explores which are its effects upon the binding force of the law and when they occur. Finally, it tries to employ this concept in describing the way in which the m.p. Mitis Iudex has been accepted and implemented in some local Churches.

  7. Physiological and molecular characterization of genetic competence in Streptococcus sanguinis.

    Science.gov (United States)

    Rodriguez, A M; Callahan, J E; Fawcett, P; Ge, X; Xu, P; Kitten, T

    2011-04-01

    Streptococcus sanguinis is a major component of the oral flora and an important cause of infective endocarditis. Although S. sanguinis is naturally competent, genome sequencing has suggested significant differences in the S. sanguinis competence system relative to those of other streptococci. An S. sanguinis mutant possessing an in-frame deletion in the comC gene, which encodes competence-stimulating peptide (CSP), was created. Addition of synthetic CSP induced competence in this strain. Gene expression in this strain was monitored by microarray analysis at multiple time-points from 2.5 to 30 min after CSP addition, and verified by quantitative reverse transcription-polymerase chain reaction. Over 200 genes were identified whose expression was altered at least two-fold in at least one time point, with the majority upregulated. The 'late' response was typical of that seen in previous studies. However, comparison of the 'early' response in S. sanguinis with that of other oral streptococci revealed unexpected differences with regard to the number of genes induced, the nature of those genes, and their putative upstream regulatory sequences. Streptococcus sanguinis possesses a comparatively limited early response, which may define a minimal streptococcal competence regulatory circuit. © 2011 John Wiley & Sons A/S.

  8. Phylogenetic analysis of glucosyltransferases and implications for the coevolution of mutans streptococci with their mammalian hosts.

    Directory of Open Access Journals (Sweden)

    Silvia Argimón

    Full Text Available Glucosyltransferases (Gtfs catalyze the synthesis of glucans from sucrose and are produced by several species of lactic-acid bacteria. The oral bacterium Streptococcus mutans produces large amounts of glucans through the action of three Gtfs. GtfD produces water-soluble glucan (WSG, GtfB synthesizes water-insoluble glucans (WIG and GtfC produces mainly WIG but also WSG. These enzymes, especially those synthesizing WIG, are of particular interest because of their role in the formation of dental plaque, an environment where S. mutans can thrive and produce lactic acid, promoting the formation of dental caries. We sequenced the gtfB, gtfC and gtfD genes from several mutans streptococcal strains isolated from the oral cavity of humans and searched for their homologues in strains isolated from chimpanzees and macaque monkeys. The sequence data were analyzed in conjunction with the available Gtf sequences from other bacteria in the genera Streptococcus, Lactobacillus and Leuconostoc to gain insights into the evolutionary history of this family of enzymes, with a particular emphasis on S. mutans Gtfs. Our analyses indicate that streptococcal Gtfs arose from a common ancestral progenitor gene, and that they expanded to form two clades according to the type of glucan they synthesize. We also show that the clade of streptococcal Gtfs synthesizing WIG appeared shortly after the divergence of viviparous, dentate mammals, which potentially contributed to the formation of dental plaque and the establishment of several streptococci in the oral cavity. The two S. mutans Gtfs capable of WIG synthesis, GtfB and GtfC, are likely the product of a gene duplication event. We dated this event to coincide with the divergence of the genomes of ancestral early primates. Thus, the acquisition and diversification of S. mutans Gtfs predates modern humans and is unrelated to the increase in dietary sucrose consumption.

  9. Effects of Psidium guajava Leaf Infusion on Streptococci viridans

    Directory of Open Access Journals (Sweden)

    Hing Yi Chen

    2016-09-01

    Full Text Available Background: Dental caries is recognized as the most important oral burden. It is caused by the formation of lactate acid formed through reaction of bacteria and carbohydrates. Streptococci viridans has been proven as the primary etiologic agents for dental caries. Low accessibility in oral care services leads the Indonesian community to use plants in order to prevent dental caries. One of those plants is Psidium guajava (pink guava. The leaves were suggested to have antimicrobial effects on some gram-positive bacteria. When the organism is resistant to specific substance tested on media, a circular/inhibition zone around a disc containing antimicrobial substance was formed. The purpose of this study was to identify the presence of inhibition zones by infusion of Psidium guajava leaf on Streptococci viridians in vitro. Methods: This laboratory experiment was carried out in September to October 2014 at the Microbiology Laboratory, Faculty of Medicine, Universitas Padjadjaran. Infusions of Psidium guajava leaf were made into four different concentrations (10%, 25%, 50% and 100%, respectively and the identification of inhibition zones on Streptococci viridans obtained from the laboratory was tested using modified disk diffusion test. Distilled water acted as negative control. The results were then interpreted after 24 hours of incubation. Every procedure was repeated three times. Results: All four concentrations of Psidium guajava leaf infusions have formed inhibition zones on the media, with the highest concentration (100% producing largest average diameter. Conclusions: The infusion of Psidium guajava leaf produces inhibition zones on Streptococci virdans in vitro.

  10. Iodophilic polysaccharide synthesis, acid production and growth in oral streptococci

    NARCIS (Netherlands)

    Houte, J. van; Winkler, K.C.; Jansen, H.M.

    The relation between iodophilic polysaccharide formation, acid production and growth in α-haemolytic streptococci, isolated from human dental plaque, was studied. In experiments with resting cell suspensions, or with cells growing at a low rate, all strains synthesizing iodophilic polysaccharide

  11. Inhibition of Streptococcus mutans NS adhesion to glass with and without a salivary conditioning film by biosurfactant-releasing Streptococcus mitis strains

    NARCIS (Netherlands)

    van Hoogmoed, CG; van der Kuijl-Booij, M; van der Mei, HC; Busscher, HJ

    The release of biosurfactants by adhering microorganisms as a defense mechanism against other colonizing strains on the same substratum surface has been described previously for probiotic bacteria in the urogenital tract, the intestines, and the oropharynx but not for microorganisms in the oral

  12. Comparative genomics of the dairy isolate Streptococcus macedonicus ACA-DC 198 against related members of the Streptococcus bovis/Streptococcus equinus complex.

    Science.gov (United States)

    Papadimitriou, Konstantinos; Anastasiou, Rania; Mavrogonatou, Eleni; Blom, Jochen; Papandreou, Nikos C; Hamodrakas, Stavros J; Ferreira, Stéphanie; Renault, Pierre; Supply, Philip; Pot, Bruno; Tsakalidou, Effie

    2014-04-08

    Within the genus Streptococcus, only Streptococcus thermophilus is used as a starter culture in food fermentations. Streptococcus macedonicus though, which belongs to the Streptococcus bovis/Streptococcus equinus complex (SBSEC), is also frequently isolated from fermented foods mainly of dairy origin. Members of the SBSEC have been implicated in human endocarditis and colon cancer. Here we compare the genome sequence of the dairy isolate S. macedonicus ACA-DC 198 to the other SBSEC genomes in order to assess in silico its potential adaptation to milk and its pathogenicity status. Despite the fact that the SBSEC species were found tightly related based on whole genome phylogeny of streptococci, two distinct patterns of evolution were identified among them. Streptococcus macedonicus, Streptococcus infantarius CJ18 and Streptococcus pasteurianus ATCC 43144 seem to have undergone reductive evolution resulting in significantly diminished genome sizes and increased percentages of potential pseudogenes when compared to Streptococcus gallolyticus subsp. gallolyticus. In addition, the three species seem to have lost genes for catabolizing complex plant carbohydrates and for detoxifying toxic substances previously linked to the ability of S. gallolyticus to survive in the rumen. Analysis of the S. macedonicus genome revealed features that could support adaptation to milk, including an extra gene cluster for lactose and galactose metabolism, a proteolytic system for casein hydrolysis, auxotrophy for several vitamins, an increased ability to resist bacteriophages and horizontal gene transfer events with the dairy Lactococcus lactis and S. thermophilus as potential donors. In addition, S. macedonicus lacks several pathogenicity-related genes found in S. gallolyticus. For example, S. macedonicus has retained only one (i.e. the pil3) of the three pilus gene clusters which may mediate the binding of S. gallolyticus to the extracellular matrix. Unexpectedly, similar findings were

  13. Penetration of Streptococcus sobrinus and Streptococcus sanguinis into dental enamel.

    Science.gov (United States)

    Kneist, Susanne; Nietzsche, Sandor; Küpper, Harald; Raser, Gerhard; Willershausen, Brita; Callaway, Angelika

    2015-10-01

    The aim of this pilot study was to assess the difference in virulence of acidogenic and aciduric oral streptococci in an in vitro caries model using their penetration depths into dental enamel. 30 caries-free extracted molars from 11- to 16-year-olds were cleaned ultrasonically for 1 min with de-ionized water and, after air-drying, embedded in epoxy resin. After 8-h of setting at room temperature, the specimens were ground on the buccal side with SiC-paper 1200 (particle size 13-16 μm). Enamel was removed in circular areas sized 3 mm in diameter; the mean depth of removed enamel was 230 ± 60 μm. 15 specimens each were incubated anaerobically under standardized conditions with 24 h-cultures of Streptococcus sanguinis 9S or Streptococcus sobrinus OMZ 176 in Balmelli broth at 37 ± 2 °C; the pH-values of the broths were measured at the beginning and end of each incubation cycle. After 2, 4, 6, 8, and 10 weeks 3 teeth each were fixed in 2.5% glutaraldehyde in cacodylate buffer for 24 h, washed 3× and dehydrated 30-60min by sequential washes through a series of 30-100% graded ethanol. The teeth were cut in half longitudinally; afterward, two slits were made to obtain fracture surfaces in the infected area. After critical-point-drying the fragments were gold-sputtered and viewed in a scanning electron microscope at magnifications of ×20-20,000. After 10 weeks of incubation, penetration of S. sanguinis of 11.13 ± 24.04 μm below the break edges into the enamel was observed. The invasion of S. sobrinus reached depths of 87.53 ± 76.34 μm. The difference was statistically significant (paired t test: p = 0.033). The experimental penetration depths emphasize the importance of S. sanguinis versus S. sobrinus in the context of the extended ecological plaque hypothesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Comparison of genes required for H2O2 resistance in Streptococcus gordonii and Streptococcus sanguinis

    Science.gov (United States)

    Xu, Yifan; Itzek, Andreas

    2014-01-01

    Hydrogen peroxide (H2O2) is produced by several members of the genus Streptococcus mainly through the pyruvate oxidase SpxB under aerobic growth conditions. The acute toxic nature of H2O2 raises the interesting question of how streptococci cope with intrinsically produced H2O2, which subsequently accumulates in the microenvironment and threatens the closely surrounding population. Here, we investigate the H2O2 susceptibility of oral Streptococcus gordonii and Streptococcus sanguinis and elucidate potential mechanisms of how they protect themselves from the deleterious effect of H2O2. Both organisms are considered primary colonizers and occupy the same intraoral niche making them potential targets for H2O2 produced by other species. We demonstrate that S. gordonii produces relatively more H2O2 and has a greater ability for resistance to H2O2 stress. Functional studies show that, unlike in Streptococcus pneumoniae, H2O2 resistance is not dependent on a functional SpxB and confirms the important role of the ferritin-like DNA-binding protein Dps. However, the observed increased H2O2 resistance of S. gordonii over S. sanguinis is likely to be caused by an oxidative stress protection machinery present even under anaerobic conditions, while S. sanguinis requires a longer period of time for adaptation. The ability to produce more H2O2 and be more resistant to H2O2 might aid S. gordonii in the competitive oral biofilm environment, since it is lower in abundance yet manages to survive quite efficiently in the oral biofilm. PMID:25280752

  15. Motivational Interviewing Tailored Interventions for Heart Failure (MITI-HF): study design and methods.

    Science.gov (United States)

    Masterson Creber, Ruth; Patey, Megan; Dickson, Victoria Vaughan; DeCesaris, Marissa; Riegel, Barbara

    2015-03-01

    Lack of engagement in self-care is common among patients needing to follow a complex treatment regimen, especially patients with heart failure who are affected by comorbidity, disability and side effects of poly-pharmacy. The purpose of Motivational Interviewing Tailored Interventions for Heart Failure (MITI-HF) is to test the feasibility and comparative efficacy of an MI intervention on self-care, acute heart failure physical symptoms and quality of life. We are conducting a brief, nurse-led motivational interviewing randomized controlled trial to address behavioral and motivational issues related to heart failure self-care. Participants in the intervention group receive home and phone-based motivational interviewing sessions over 90-days and those in the control group receive care as usual. Participants in both groups receive patient education materials. The primary study outcome is change in self-care maintenance from baseline to 90-days. This article presents the study design, methods, plans for statistical analysis and descriptive characteristics of the study sample for MITI-HF. Study findings will contribute to the literature on the efficacy of motivational interviewing to promote heart failure self-care. We anticipate that using an MI approach can help patients with heart failure focus on their internal motivation to change in a non-confrontational, patient-centered and collaborative way. It also affirms their ability to practice competent self-care relevant to their personal health goals. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Streptococcus massiliensis in the human mouth: a phylogenetic approach for the inference of bacterial habitats.

    Science.gov (United States)

    Póntigo, F; Silva, C; Moraga, M; Flores, S V

    2015-12-29

    Streptococcus is a diverse bacterial lineage. Species of this genus occupy a myriad of environments inside humans and other animals. Despite the elucidation of several of these habitats, many remain to be identified. Here, we explore a methodological approach to reveal unknown bacterial environments. Specifically, we inferred the phylogeny of the Mitis group by analyzing the sequences of eight genes. In addition, information regarding habitat use of species belonging to this group was obtained from the scientific literature. The oral cavity emerged as a potential, previously unknown, environment of Streptococcus massiliensis. This phylogeny-based prediction was confirmed by species-specific polymerase chain reaction (PCR) amplification. We propose employing a similar approach, i.e., use of bibliographic data and molecular phylogenetics as predictive methods, and species-specific PCR as confirmation, in order to reveal other unknown habitats in further bacterial taxa.

  17. Group B Streptococcus and Pregnancy

    Science.gov (United States)

    ... B Strep and Pregnancy • What is group B streptococcus (GBS)? • What does it mean to be colonized ... planned cesarean birth? •Glossary What is group B streptococcus (GBS)? Group B streptococcus is one of the ...

  18. Cross-infection between cats and cows: Origin and control of Streptococcus canis mastitis in a dairy herd

    OpenAIRE

    Tikofsky, L L; Zadoks, R N

    2005-01-01

    Group G streptococci in animals usually belong to the species Streptococcus canis and are most commonly found in dogs and cats. Occasionally, Strep. canis is detected in milk from dairy cows. An outbreak of Strep. canis mastitis in a dairy herd is described. Based on results from bacterial culture and ribotyping, a cat with chronic sinusitis was the most likely source of the outbreak. Subsequent cow-to-cow transmission of Strep. canis was facilitated by poor udder health management, including...

  19. Natural History of Streptococcus sanguinis in the Oral Cavity of Infants: Evidence for a Discrete Window of Infectivity

    OpenAIRE

    Caufield, Page W.; Dasanayake, Ananda P.; Li, Yihong; Pan, Yaping; Hsu, Jay; Hardin, J. Michael

    2000-01-01

    The heterogeneous group of oral bacteria within the sanguinis (sanguis) streptococci comprise members of the indigenous biota of the human oral cavity. While the association of Streptococcus sanguinis with bacterial endocarditis is well described in the literature, S. sanguinis is thought to play a benign, if not a beneficial, role in the oral cavity. Little is known, however, about the natural history of S. sanguinis and its specific relationship with other oral bacteria. As part of a longit...

  20. Partial purification of the ATP-driven calcium pump of Streptococcus sanguis

    International Nuclear Information System (INIS)

    Lynn, A.R.; Rosen, B.P.

    1986-01-01

    ATP-dependent transport of calcium has been observed in several species of streptococci as uptake of 45 Ca 2+ into everted membrane vesicles. Membranes from Streptococcus sanguis and Streptococcus faecalis were solubilized with octyl-β-D-glucoside or Triton X-100, and the extracts reconstituted into proteoliposomes containing Escherichia coli or soybean phospholipid. Calcium transport in reconstituted proteoliposomes was insensitive to the ionophores nigericin and valinomycin and was unaffected by the F 0 F 1 inhibitor N,N'-dicyclohexylcarbodiimide. Uptake was inhibited by ortho-vanadate with a K/sub i/ in the micromolar range. These results demonstrate that the reconstituted transport activities are not the result of ATP-driven proton pumping via the F 0 F 1 coupled to a calcium/proton antiporter and suggest that existence of a calcium translocating ATPase. Partial purification of the transport activity from Streptococcus sanguis has been achieved using density gradient centrifugation and FPLC

  1. Analysis of surface structures of Cladonia mitis podetia in historic and recent collections from Greenland

    DEFF Research Database (Denmark)

    Heide-Jørgensen, Henning; Johnsen, Ib

    1995-01-01

    Field observations in Greenland combined with a scanning electron microscopical survey have revealed a hitherto undescribed correspondence in the distribution of a brownish colour and a crust-like surface structure formed by hyphae at exposed parts of the shoot tips of podetia of Cladonia mitis...

  2. Interactions between oral bacteria: inhibition of Streptococcus mutans bacteriocin production by Streptococcus gordonii.

    Science.gov (United States)

    Wang, Bing-Yan; Kuramitsu, Howard K

    2005-01-01

    Streptococcus mutans has been recognized as an important etiological agent in human dental caries. Some strains of S. mutans also produce bacteriocins. In this study, we sought to demonstrate that bacteriocin production by S. mutans strains GS5 and BM71 was mediated by quorum sensing, which is dependent on a competence-stimulating peptide (CSP) signaling system encoded by the com genes. We also demonstrated that interactions with some other oral streptococci interfered with S. mutans bacteriocin production both in broth and in biofilms. The inhibition of S. mutans bacteriocin production by oral bacteria was stronger in biofilms than in broth. Using transposon Tn916 mutagenesis, we identified a gene (sgc; named for Streptococcus gordonii challisin) responsible for the inhibition of S. mutans bacteriocin production by S. gordonii Challis. Interruption of the sgc gene in S. gordonii Challis resulted in attenuated inhibition of S. mutans bacteriocin production. The supernatant fluids from the sgc mutant did not inactivate the exogenous S. mutans CSP as did those from the parent strain Challis. S. gordonii Challis did not inactivate bacteriocin produced by S. mutans GS5. Because S. mutans uses quorum sensing to regulate virulence, strategies designed to interfere with these signaling systems may have broad applicability for biological control of this caries-causing organism.

  3. Organization of the capsule biosynthesis gene locus of the oral streptococcus Streptococcus anginosus.

    Science.gov (United States)

    Tsunashima, Hiroyuki; Miyake, Katsuhide; Motono, Makoto; Iijima, Shinji

    2012-03-01

    The capsular polysaccharide (CPS) of the important oral streptococcus Streptococcus anginosus, which causes endocarditis, and the genes for its synthesis have not been clarified. In this study, we investigated the gene locus required for CPS synthesis in S. anginosus. Southern hybridization using the cpsE gene of the well-characterized bacterium S. agalactiae revealed that there is a similar gene in the genome of S. anginosus. By using the colony hybridization technique and inverse PCR, we isolated the CPS synthesis (cps) genes of S. anginosus. This gene cluster consisted of genes containing typical regulatory genes, cpsA-D, and glycosyltransferase genes coding for glucose, rhamnose, N-acetylgalactosamine, and galactofuranose transferases. Furthermore, we confirmed that the cps locus is required for CPS synthesis using a mutant strain with a defective cpsE gene. The cps cluster was found to be located downstream the nrdG gene, which encodes ribonucleoside triphosphate reductase activator, as is the case in other oral streptococci such as S. gordonii and S. sanguinis. However, the location of the gene cluster was different from those of S. pneumonia and S. agalactiae. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  4. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry identification of large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G.

    Science.gov (United States)

    Jensen, Christian Salgård; Dam-Nielsen, Casper; Arpi, Magnus

    2015-08-01

    The aim of this study was to investigate whether large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G can be adequately identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-ToF). Previous studies show varying results, with an identification rate from below 50% to 100%. Large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G isolated from blood cultures between January 1, 2007 and May 1, 2012 were included in the study. Isolates were identified to the species level using a combination of phenotypic characteristics and 16s rRNA sequencing. The isolates were subjected to MALDI-ToF analysis. We used a two-stage approach starting with the direct method. If no valid result was obtained we proceeded to an extraction protocol. Scores above 2 were considered valid identification at the species level. A total of 97 Streptococcus pyogenes, 133 Streptococcus dysgalactiae, and 2 Streptococcus canis isolates were tested; 94%, 66%, and 100% of S. pyogenes, S. dysgalactiae, and S. canis, respectively, were correctly identified by MALDI-ToF. In most instances when the isolates were not identified by MALDI-ToF this was because MALDI-ToF was unable to differentiate between S. pyogenes and S. dysgalactiae. By removing two S. pyogenes reference spectra from the MALDI-ToF database the proportion of correctly identified isolates increased to 96% overall. MALDI-ToF is a promising method for discriminating between S. dysgalactiae, S. canis, and S. equi, although more strains need to be tested to clarify this.

  5. Phylogenomics and the Dynamic Genome Evolution of the Genus Streptococcus

    Science.gov (United States)

    Richards, Vincent P.; Palmer, Sara R.; Pavinski Bitar, Paulina D.; Qin, Xiang; Weinstock, George M.; Highlander, Sarah K.; Town, Christopher D.; Burne, Robert A.; Stanhope, Michael J.

    2014-01-01

    The genus Streptococcus comprises important pathogens that have a severe impact on human health and are responsible for substantial economic losses to agriculture. Here, we utilize 46 Streptococcus genome sequences (44 species), including eight species sequenced here, to provide the first genomic level insight into the evolutionary history and genetic basis underlying the functional diversity of all major groups of this genus. Gene gain/loss analysis revealed a dynamic pattern of genome evolution characterized by an initial period of gene gain followed by a period of loss, as the major groups within the genus diversified. This was followed by a period of genome expansion associated with the origins of the present extant species. The pattern is concordant with an emerging view that genomes evolve through a dynamic process of expansion and streamlining. A large proportion of the pan-genome has experienced lateral gene transfer (LGT) with causative factors, such as relatedness and shared environment, operating over different evolutionary scales. Multiple gene ontology terms were significantly enriched for each group, and mapping terms onto the phylogeny showed that those corresponding to genes born on branches leading to the major groups represented approximately one-fifth of those enriched. Furthermore, despite the extensive LGT, several biochemical characteristics have been retained since group formation, suggesting genomic cohesiveness through time, and that these characteristics may be fundamental to each group. For example, proteolysis: mitis group; urea metabolism: salivarius group; carbohydrate metabolism: pyogenic group; and transcription regulation: bovis group. PMID:24625962

  6. Association of viridans group streptococci from pregnant women with bacterial vaginosis and upper genital tract infection.

    OpenAIRE

    Rabe, L K; Winterscheid, K K; Hillier, S L

    1988-01-01

    The prevalence and role of viridans group streptococci in the female genital tract have not been well described. In this study of 482 pregnant women, 147 (30%) were culture positive for viridans group streptococci. Of 392 women with predominant Lactobacillus morphotypes by Gram stain (normal), 110 (28%) were colonized with viridans group streptococci, compared with 37 (41%) of 90 women with bacterial vaginosis (BV) (P = 0.02). To determine whether any species were associated with BV, 177 cons...

  7. Mechanisms of genome evolution of Streptococcus.

    Science.gov (United States)

    Andam, Cheryl P; Hanage, William P

    2015-07-01

    The genus Streptococcus contains 104 recognized species, many of which are associated with human or animal hosts. A globally prevalent human pathogen in this group is Streptococcus pneumoniae (the pneumococcus). While being a common resident of the upper respiratory tract, it is also a major cause of otitis media, pneumonia, bacteremia and meningitis, accounting for a high burden of morbidity and mortality worldwide. Recent findings demonstrate the importance of recombination and selection in driving the population dynamics and evolution of different pneumococcal lineages, allowing them to successfully evade the impacts of selective pressures such as vaccination and antibiotic treatment. We highlight the ability of pneumococci to respond to these pressures through processes including serotype replacement, capsular switching and horizontal gene transfer (HGT) of antibiotic resistance genes. The challenge in controlling this pathogen also lies in the exceptional genetic and phenotypic variation among different pneumococcal lineages, particularly in terms of their pathogenicity and resistance to current therapeutic strategies. The widespread use of pneumococcal conjugate vaccines, which target only a small subset of the more than 90 pneumococcal serotypes, provides us with a unique opportunity to elucidate how the processes of selection and recombination interact to generate a remarkable level of plasticity and heterogeneity in the pneumococcal genome. These processes also play an important role in the emergence and spread of multi-resistant strains, which continues to pose a challenge in disease control and/or eradication. The application of population of genomic approaches at different spatial and temporal scales will help improve strategies to control this global pathogen, and potentially other pathogenic streptococci. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Acute guttate psoriasis patients have positive streptococcus hemolyticus throat cultures and elevated antistreptococcal M6 protein titers.

    Science.gov (United States)

    Zhao, Guang; Feng, Xiaoling; Na, Aihua; Yongqiang, Jiang; Cai, Qing; Kong, Jian; Ma, Huijun

    2005-02-01

    To further study the role of Streptococci hemolyticus infection and streptococcal M6 protein in the pathogenesis of acute guttate psoriasis, streptococcal cultures were taken from the throats of 68 patients with acute guttate psoriasis. PCR technique was applied to detect M6 protein encoding DNA from those cultured streptococci. Pure M6 protein was obtained by Sephacry/S-200HR and Mono-Q chromatography from proliferated Streptococcus hemolyticus. Antistreptococcal M6 protein titers were measured in the serum of patients with acute guttate psoriasis, plaque psoriasis and healthy controls by ELISA. A high incidence of Streptococcus hemolyticus culture was observed in the guttate psoriatic group compared with the plaque psoriasis and control groups. Fourteen strains of Streptococcus hemolyticus were cultured from the throats of 68 acute guttate psoriasis patients. Of these, 5 strains contain DNA encoding the M6 protein gene as confirmed by PCR technique. More than 85% purification of M6 protein was obtained from Streptococcus pyogenes. Applying our pure M6 protein with the ELISA methods, we found that the titer of antistreptococcal M6 protein was significantly higher in the serum of guttate psoriasis patients than in the control or plaque psoriasis groups (P M6 protein in their sera.

  9. Epidermólise bolhosa distrófica recessiva mitis: relato de caso clínico Recessive dystrophic epidermolysis bullosa mitis: case report

    Directory of Open Access Journals (Sweden)

    Thaiz Gava Rigoni Gürtler

    2005-10-01

    Full Text Available As epidermólises bolhosas são dermatoses bolhosas congênitas que levam à formação de bolhas espontaneamente ou após trauma. São reconhecidos três grupos de da doença, de acordo com o segundo consenso internacional: simples, juncional e distrófica. Nas formas distróficas, o defeito genético deve-se à mutação no gene COL7A1, responsável pela codificação do colágeno VII, principal constituinte das fibrilas de ancoragem, que participam na aderência da lâmina densa à derme. Os autores relatam o caso de paciente do sexo feminino, de 15 anos, apresentando ulcerações nas pernas, bolhas serosas e lesões atrófico-acastanhadas nos braços e tronco. Foram observadas distrofias ungueais e alterações dentárias, iniciadas a partir do nascimento. O exame histopatológico da bolha revelou quadro compatével com epidermólise bolhosa, que, associado aos dados clínicos, permitiram a classificação do caso na forma distrófica recessiva mitis.Epidermolysis bullosa are congenital bullous dermatoses that lead to spontaneous or post-traumatic formation of blisters. There are three recognized disease groups, according to the second international consensus: simplex, junctional and dystrophic. The genetic defect of the dystrophic forms is due to a mutation in the COL7A1 gene, which is responsible for codifying collagen VII, the main representative of anchoring fibrils, which participate in the adherence of the "lamina densa" to the dermis. The authors describe a case of a 15 year-old female patient who presented ulcers on her legs, serous blisters and atrophic scars on her arms and body. Dystrophic ungual and dental abnormalities had also been observed since her birth. Blister histopathological examination was compatible with epidermolysis bullosa, which, in association with clinical data, allowed the classification of recessive distrophic epidermolysis bullosa.

  10. Analysis of multidrug resistant group B streptococci with reduced penicillin susceptibility forming small, less hemolytic colonies.

    Directory of Open Access Journals (Sweden)

    Hirotsugu Banno

    Full Text Available Group B streptococci (GBS; Streptococcus agalactiae are the leading cause of neonatal invasive diseases and are also important pathogens for elderly adults. Until now, nearly all GBS with reduced penicillin susceptibility (PRGBS have shown β-hemolytic activity and grow on sheep blood agar. However, we have previously reported three PRGBS clinical isolates harboring a CylK deletion that form small less hemolytic colonies. In this study, we examined the causes of small, less hemolytic colony formation in these clinical isolates. Isogenic strains were sequenced to identify the mutation related to a small colony size. We identified a 276_277insG nucleic acid insertion in the thiamin pyrophosphokinase (tpk gene, resulting in premature termination at amino acid 103 in TPK, as a candidate mutation responsible for small colony formation. The recombinant strain Δtpk, which harbored the 276_277insG insertion in the tpk gene, showed small colony formation. The recombinant strain ΔcylK, which harbored the G379T substitution in cylK, showed a reduction in hemolytic activity. The phenotypes of both recombinant strains were complemented by the expression of intact TPK or CylK, respectively. Moreover, the use of Rapid ID 32 API and VITEK MS to identify strains as GBS was evaluated clinical isolates and recombinant strains. VITEK MS, but not Rapid ID 32 API, was able to accurately identify the strains as GBS. In conclusion, we determined that mutations in tpk and cylK caused small colonies and reduced hemolytic activity, respectively, and characterized the clinical isolates in detail.

  11. Genetic basis of coaggregation receptor polysaccharide biosynthesis in Streptococcus sanguinis and related species.

    Science.gov (United States)

    Yang, J; Yoshida, Y; Cisar, J O

    2014-02-01

    Interbacterial adhesion between streptococci and actinomyces promotes early dental plaque biofilm development. Recognition of coaggregation receptor polysaccharides (RPS) on strains of Streptococcus sanguinis, Streptococcus gordonii and Streptococcus oralis by Actinomyces spp. type 2 fimbriae is the principal mechanism of these interactions. Previous studies of genetic loci for synthesis of RPS (rps) and RPS precursors (rml, galE1 and galE2) in S. gordonii 38 and S. oralis 34 revealed differences between these strains. To determine whether these differences are strain-specific or species-specific, we identified and compared loci for polysaccharide biosynthesis in additional strains of these species and in several strains of the previously unstudied species, S. sanguinis. Genes for synthesis of RPS precursors distinguished the rps loci of different streptococci. Hence, rml genes for synthesis of TDP-L-Rha were in rps loci of S. oralis strains but at other loci in S. gordonii and S. sanguinis. Genes for two distinct galactose epimerases were also distributed differently. Hence, galE1 for epimerization of UDP-Glc and UDP-Gal was in galactose operons of S. gordonii and S. sanguinis strains but surprisingly, this gene was not present in S. oralis. Moreover, galE2 for epimerization of both UDP-Glc and UDP-Gal and UDP-GlcNAc and UDP-GalNAc was at a different locus in each species, including rps operons of S. sanguinis. The findings provide insight into cell surface properties that distinguish different RPS-producing streptococci and open an approach for identifying these bacteria based on the arrangement of genes for synthesis of polysaccharide precursors. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  12. THE MODE OF ACTION OF SULFANILAMIDE ON STREPTOCOCCUS. II.

    Science.gov (United States)

    Gay, F P; Clark, A R; Street, J A; Miles, D W

    1939-04-30

    The precise mode of therapeutic action of sulfanilamide on streptococcus can be arrived at only by considering the sum total of factors that inhibit or favor the natural growth of the microorganism under the experimental conditions that obtain, whether in vivo or in vitro. Too sweeping conclusions have hitherto been drawn from the study of a single variable factor, such as an unfavorable temperature or the absence or presence of peptone. We have attempted here to analyze the factors that have hitherto been recognized and some new ones, but particularly the relationship of these factors to one another. The result obtained on adding sulfanilamide to the streptococcus in the test tube is usually bacteriostasis and not complete destruction of even small numbers of bacteria. This is on the condition that the suspending medium is a favorable one for the growth of the microorganism; the more growth-promoting the medium is the less the bacteriostasis. If, on the other hand, the medium is too poor, or one that in itself inhibits growth, the addition of sulfanilamide may lead to sterilization of the culture. The conditions for growth of the streptococcus in the body of the rabbit or mouse, depend on the strain of bacteria used, but are on the whole favorable. Defence, however, in the form of phagocytosis by both polymorphonuclear and by mononuclear cells is attempted even in the susceptible animal. When sulfanilamide is used to treat such an animal, or when sulfanilamide-grown (inhibited) streptococci are employed, phagocytosis is pronounced, whether studied in the test tube or in the animal body. In the rabbit the delay by sulfanilamide and resultant increased phagocytosis by polymorphonuclears allows mononuclear cells to accumulate and recovery may result. Sulfanilamide not only does not completely destroy the streptococcus but does not even impair its innate virulence. It acts upon the streptococcus not only by inhibiting growth but by a temporary inhibition of hemotoxin

  13. Exploring internal features of 16S rRNA gene for identification of clinically relevant species of the genus Streptococcus

    Science.gov (United States)

    2011-01-01

    Background Streptococcus is an economically important genus as a number of species belonging to this genus are human and animal pathogens. The genus has been divided into different groups based on 16S rRNA gene sequence similarity. The variability observed among the members of these groups is low and it is difficult to distinguish them. The present study was taken up to explore 16S rRNA gene sequence to develop methods that can be used for preliminary identification and can supplement the existing methods for identification of clinically-relevant isolates of the genus Streptococcus. Methods 16S rRNA gene sequences belonging to the isolates of S. dysgalactiae, S. equi, S. pyogenes, S. agalactiae, S. bovis, S. gallolyticus, S. mutans, S. sobrinus, S. mitis, S. pneumoniae, S. thermophilus and S. anginosus were analyzed with the purpose to define genetic variability within each species to generate a phylogenetic framework, to identify species-specific signatures and in-silico restriction enzyme analysis. Results The framework based analysis was used to segregate Streptococcus spp. previously identified upto genus level. This segregation was validated using species-specific signatures and in-silico restriction enzyme analysis. 43 uncharacterized Streptococcus spp. could be identified using this approach. Conclusions The markers generated exploring 16S rRNA gene sequences provided useful tool that can be further used for identification of different species of the genus Streptococcus. PMID:21702978

  14. A mariner transposon vector adapted for mutagenesis in oral streptococci

    DEFF Research Database (Denmark)

    Nilsson, Martin; Christiansen, Natalia; Høiby, Niels

    2014-01-01

    This article describes the construction and characterization of a mariner-based transposon vector designed for use in oral streptococci, but with a potential use in other Gram-positive bacteria. The new transposon vector, termed pMN100, contains the temperature-sensitive origin of replication rep...... 5000 mutants was used in a screen to identify genes involved in the production of sucrose-dependent extracellular matrix components. Mutants with transposon inserts in genes encoding glycosyltransferases and the competence-related secretory locus were predominantly found in this screen....

  15. Plasmid-mediated UV-protection in Streptococcus lactis

    Energy Technology Data Exchange (ETDEWEB)

    Chopin, M.C.; Rouault, A. (Institut National de la Recherche Agronomique, Rennes (France). Lab. de Recherches de Technologie Laitiere); Moillo-Batt, A. (Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital de Pontchaillon, 35 - Rennes (France))

    1985-02-01

    Streptococcus lactis strain IL594 contains 9 plasmids, designated pIL1 to pIL9. On the basis of protoplast-induced curing experiments the authors showed that derivatives containing pIL7 were resistant to UV-irradiation while derivatives lacking pIL7 were sensitive. The pIL7-determined UV-protection was confirmed by co-transfer of the plasmid and of the character into a plasmid-free derivative of S. lactis IL594. Moreover, prophage induction required higher UV-fluence in this derivative carrying pIL7 than in the plasmid-free strain. This is the first report of a plasmid-mediated UV-protection in group N streptococci.

  16. Comparison of Streptokinase Activity from Streptococcus mutans using Different Substrates

    Directory of Open Access Journals (Sweden)

    Muhammad Anjum Zia*, Rana Faisal, Rao Zahid Abbas1, Gull-e-Faran, Muhammad Kashif Saleemi2 and Junaid Ali Khan3

    2013-01-01

    Full Text Available Streptokinase is a novel bacterial fibrinolytic enzyme that binds and activates plasminogen and is produced by several species of Streptococci. Streptococcus mutans was selected for optimum production of streptokinase using corn steep liquor, molasses, rice polishing and sugarcane bagass in liquid state fermentation. Substrates were applied in different concentrations ranging from 0.1-0.8%. Maximum fibrinolytic activity was observed by 0.3% corn steep liquor, 0.5% molasses and rice polishing and 0.4% by sugarcane bagass. The fibrinolytic activity achieved by fibrin clot lysis method was 5.5, 5.08, 5.16 and 4.75 units using corn steep liquor, molasses, rice polishing and sugarcane bagass, respectively.

  17. Plasmid-mediated UV-protection in Streptococcus lactis

    International Nuclear Information System (INIS)

    Chopin, M.-C.; Rouault, A.

    1985-01-01

    Streptococcus lactis strain IL594 contains 9 plasmids, designated pIL1 to pIL9. On the basis of protoplast-induced curing experiments the authors showed that derivatives containing pIL7 were resistant to UV-irradiation while derivatives lacking pIL7 were sensitive. The pIL7-determined UV-protection was confirmed by cotransfer of the plasmid and of the character into a plasmid-free derivative of S. lactis IL594. Moreover, prophage induction required higher UV-fluence in this derivative carrying pIL7 than in the plasmid-free strain. This is the first report of a plasmid-mediated UV-protection in group N streptococci. (orig.)

  18. [Synthesis and degradation of hyaluronic acid by bacteria of Streptococcus genus].

    Science.gov (United States)

    Beloded, A V; Samoĭlenko, I I; Tsepilov, R N

    2010-01-01

    Modern data on metabolism of hyaluronic acid by bacteria from Streptococcus genus are presented. Several species of bacteria forming capsule from hyaluronic acid, which is analogous to glycosaminoglycan of vertebrates, are considered. Different aspects of hyaluronic acid synthesis are described: biochemical synthesis pathway, genetic basis, regulation of expression of genes belonging to hyaluronic acid synthesis operon. Biological role and physiologic importance of hyaluronic acid for bacteria, including its role in overcoming immune barrier by pathogenic species, are discussed. Process of depolymerization of hyaluronic acid in presence of hyaluronatlyases secreted by certain streptococci is considered. Characteristic of streptococcal enzyme hyaluronatlyase, its mechanism of catalytic effect, and biological function are presented.

  19. Seroprevalence of simian immunodeficiency virus in wild and captive born Sykes' monkeys (Cercopithecus mitis) in Kenya

    OpenAIRE

    Otsyula Moses G; Robinson James; Elliott Debra; Munene Elephas; Ellis Brett R; Michael Scott F

    2004-01-01

    Abstract Background The Sykes' monkey and related forms (Cercopithecus mitis) make up an abundant, widespread and morphologically diverse species complex in eastern Africa that naturally harbors a distinct simian immunodeficiency virus (SIVsyk). We carried out a retrospective serological survey of SIV infection from both wild and captive Sykes' monkeys from Kenya. We compared two commercially available, cross-reactive ELISA tests using HIV antigens with a novel SIVsyk antigen-specific Western...

  20. The role of zinc in the interplay between pathogenic streptococci and their hosts

    NARCIS (Netherlands)

    Shafeeq, Sulman; Kuipers, Oscar P.; Kloosterman, Tomas G.

    Recent studies on pathogenic streptococci have revealed that zinc is a pivotal metal ion in their interaction with the host. In these streptococci, systems exist that ensure optimal use of zinc from the surrounding milieu, as well as export of zinc when concentrations exceed tolerance levels. Zinc

  1. Isolation and characterization of Streptococcus spp. group B in Nile tilapias (Oreochromis niloticus reared in hapas nets and earth nurseries in the northern region of Parana State, Brazil

    Directory of Open Access Journals (Sweden)

    Salvador Rogério

    2005-01-01

    Full Text Available The objective of this study was to isolate and characterize Streptococcus spp. in Nile tilapias (Oreochromis niloticus reared in net-pens and earth nurseries. Eight intensive tilapia-rearing farms were investigated in north Paraná, Brazil from April 1st 2001 to April 30th 2002. The fish were reared in a system of hapas nets on four farms and in earth nurseries on other four farms. A total of 370 samples were analyzed of material collected from 120 fish (brain, liver, kidney, skin scrapes, ascites liquid and eye that were sown on BHI agar (Brain Heart Infusion supplemented with 1% yeast extract and sheep blood. Streptococcus spp. was isolated in 36 of the samples (18 brain, eight liver, eight kidney and two ascites liquid from 25 fish. Streptococci were isolated in both systems, almost in the same proportion. First the streptococci were characterized by the catalase and esculin test, growth in methylene blue and sodium chloride at 6.5%. They were classified in groups by the Slidex Strepto-Kit (BioMerieux, France. The phenotypic characteristics were determined by the Api 20 Strep microtest system (BioMerieux, France. The 36 Streptococcus spp. samples did not present hemolysis and were classified as Lancefield group B. Further 16 samples were identified as Streptococcus agalactiae and 20 were not identified by the Api 20 Strep, but presented the same biochemical profile described for the reference strain of Streptococcus difficile (ND-2-22.

  2. In vivo antimalarial activity of crude extracts and solvent fractions of leaves of Strychnos mitis in Plasmodium berghei infected mice.

    Science.gov (United States)

    Fentahun, Selamawit; Makonnen, Eyasu; Awas, Tesfaye; Giday, Mirutse

    2017-01-05

    Malaria is a major public health problem in the world which is responsible for death of millions particularly in sub-Saharan Africa. Today, the control of malaria has become gradually more complex due to the spread of drug-resistant parasites. Medicinal plants are the unquestionable source of effective antimalarials. The present study aimed to evaluate antiplasmodial activity and acute toxicity of the plant Strychnos mitis in Plasmodium berghei infected mice. Standard procedures were employed to investigate acute toxicity and 4-day suppressive effect of crude aqueous and hydro-methanolic extracts of the leaves of Strychnos mitis against P. berghei in Swiss albino mice. Water, n-hexane and chloroform fractions, obtained from crude hydro-methanolic extract, were also tested for their suppressive effect against P. berghei. All crude extracts revealed no obvious acute toxicity in mice up to the highest dose administered (2000 mg/kg). All crude and solvent fractions of the leaves of Strychnos mitis inhibited parasitaemia significantly (p antimalarial agent.

  3. Seroprevalence of simian immunodeficiency virus in wild and captive born Sykes' monkeys (Cercopithecus mitis in Kenya

    Directory of Open Access Journals (Sweden)

    Otsyula Moses G

    2004-10-01

    Full Text Available Abstract Background The Sykes' monkey and related forms (Cercopithecus mitis make up an abundant, widespread and morphologically diverse species complex in eastern Africa that naturally harbors a distinct simian immunodeficiency virus (SIVsyk. We carried out a retrospective serological survey of SIV infection from both wild and captive Sykes' monkeys from Kenya. We compared two commercially available, cross-reactive ELISA tests using HIV antigens with a novel SIVsyk antigen-specific Western blot assay and analyzed the data by origin, subspecies, age and sex. Results The SIVsyk antigen-specific Western blot assay detected more serum samples as positive than either of the cross-reactive ELISA assays. Using this assay, we found that seroprevalence is higher than previously reported, but extremely variable in wild populations (from 0.0 to 90.9%. Females were infected more often than males in both wild and captive populations. Seropositive infants were common. However, no seropositive juveniles were identified. Conclusion We have developed a specific and sensitive Western blot assay for anti-SIVsyk antibody detection. Sykes' monkeys are commonly infected with SIVsyk, but with extremely variable prevalence in the wild. Higher infection prevalence in females suggests predominantly sexual transmission. High infection prevalence in infants, but none in juveniles, suggests maternal antibodies, but little or no vertical transmission.

  4. Differentiation of Cariogenic Streptococci by Fluorescent Antibody1

    Science.gov (United States)

    Jablon, James M.; Zinner, Doran D.

    1966-01-01

    Jablon, J. M. (University of Miami, Miami, Fla.), and D. D. Zinner. Differentiation of cariogenic streptococci by fluorescent antibody. J. Bacteriol. 92:1590–1596. 1966.—Eight strains of streptococci were isolated from human carious lesions by the fluorescent-antibody (FA) technique. Seven of these strains produced experimental caries in hamsters or rats maintained on a high sucrose diet. The eighth strain was noncariogenic in animals but possessed some antigenic components in common with the cariogenic strains. On the basis of antigen-antibody reactions by microprecipitin and agar-gel diffusion patterns, the strains were divided into four groups; these groups differed with regard to their cariogenic activity in hamsters. Fluorescein-conjugated antisera, prepared against the human strains, showed some cross-reactions which interfered with the efficacy of the FA technique in differentiating between the related streptococcal groups. To eliminate these cross-reactions, a small amount of related-strain antisera was added to the fluorescein-conjugated antisera to the cariogenic strains. This technique is effective in blocking cross-reactions and should be tried wherever cross-reactions are encountered in the FA technique. Images PMID:5334765

  5. Live and heat-killed Lactobacillus spp. interfere with Streptococcus mutans and Streptococcus oralis during biofilm development on titanium surface.

    Science.gov (United States)

    Ciandrini, E; Campana, R; Baffone, W

    2017-06-01

    This research investigates the ability of live and heat-killed (HK) Lactic Acid Bacteria (LAB) to interfere with Streptococcus mutans ATCC 25175 and Streptococcus oralis ATCC 9811 during biofilm formation. Eight Lactobacillus spp. and two oral colonizers, pathogenic Streptococcus mutans and resident Streptococcus oralis, were characterized for their aggregation abilities, cell surface properties and biofilm formation ability on titanium surface. Then, the interference activity of selected live and HK Lactobacillus spp. during S. mutans and S. oralis biofilm development were performed. The cell-free culture supernatants (CFCS) anti-biofilm activity was also determined. LAB possess good abilities of auto-aggregation (from 14.19 to 28.97%) and of co-aggregation with S. oralis. The cell-surfaces characteristics were most pronounced in S. mutans and S. oralis, while the highest affinities to xylene and chloroform were observed in Lactobacillus rhamnosus ATCC 53103 (56.37%) and Lactobacillus paracasei B21060 (43.83%). S. mutans and S. oralis developed a biofilm on titanium surface, while LAB showed a limited or no ability to create biofilm. Live and HK L. rhamnosus ATCC 53103 and L. paracasei B21060 inhibited streptococci biofilm formation by competition and displacement mechanisms with no substantial differences. The CFCSs of both LAB strains, particularly the undiluted one of L. paracasei B21060, decreased S. mutans and S. oralis biofilm formation. This study evidenced the association of LAB aggregation abilities and cell-surface properties with the LAB-mediated inhibition of S. mutans and S. oralis biofilm formation. Lactobacilli showed different mechanisms of action and peculiar strain-specific characteristics, maintained also in the heat-killed LAB. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Controlled Human Infection for Vaccination Against Streptococcus Pyogenes

    Science.gov (United States)

    2018-04-26

    Streptococcus Pyogenes Pharyngitis; Streptococcus Pharyngitis; Strep Throat; Streptococcus Pyogenes Infection; Group A Streptococcus: B Hemolytic Pharyngitis; Group A Streptococcal Infection; Gram-Positive Bacterial Infections; Bacterial Infections

  7. Capsular Sialyltransferase Specificity Mediates Different Phenotypes in Streptococcus suis and Group B Streptococcus

    Directory of Open Access Journals (Sweden)

    David Roy

    2018-04-01

    Full Text Available The capsular polysaccharide (CPS represents a key virulence factor for most encapsulated streptococci. Streptococcus suis and Group B Streptococcus (GBS are both well-encapsulated pathogens of clinical importance in veterinary and/or human medicine and responsible for invasive systemic diseases. S. suis and GBS are the only Gram-positive bacteria which express a sialylated CPS at their surface. An important difference between these two sialylated CPSs is the linkage between the side-chain terminal galactose and sialic acid, being α-2,6 for S. suis but α-2,3 for GBS. It is still unclear how sialic acid may affect CPS production and, consequently, the pathogenesis of the disease caused by these two bacterial pathogens. Here, we investigated the role of sialic acid and the putative effect of sialic acid linkage modification in CPS synthesis using inter-species allelic exchange mutagenesis. To this aim, a new molecular biogenetic approach to express CPS with modified sialic acid linkage was developed. We showed that sialic acid (and its α-2,6 linkage is crucial for S. suis CPS synthesis, whereas for GBS, CPS synthesis may occur in presence of an α-2,6 sialyltransferase or in absence of sialic acid moiety. To evaluate the effect of the CPS composition/structure on sialyltransferase activity, two distinct capsular serotypes within each bacterial species were compared (S. suis serotypes 2 and 14 and GBS serotypes III and V. It was demonstrated that the observed differences in sialyltransferase activity and specificity between S. suis and GBS were serotype unrestricted. This is the first time that a study investigates the interspecies exchange of capsular sialyltransferase genes in Gram-positive bacteria. The obtained mutants represent novel tools that could be used to further investigate the immunomodulatory properties of sialylated CPSs. Finally, in spite of common CPS structural characteristics and similarities in the cps loci, sialic acid exerts

  8. Streptococcus oligofermentans Inhibits Streptococcus mutans in Biofilms at Both Neutral pH and Cariogenic Conditions.

    Science.gov (United States)

    Bao, Xudong; de Soet, Johannes Jacob; Tong, Huichun; Gao, Xuejun; He, Libang; van Loveren, Cor; Deng, Dong Mei

    2015-01-01

    Homeostasis of oral microbiota can be maintained through microbial interactions. Previous studies showed that Streptococcus oligofermentans, a non-mutans streptococci frequently isolated from caries-free subjects, inhibited the cariogenic Streptococcus mutans by the production of hydrogen peroxide (HP). Since pH is a critical factor in caries formation, we aimed to study the influence of pH on the competition between S. oligofermentans and S. mutans in biofilms. To this end, S. mutans and S. oligofermentans were inoculated alone or mixed at 1:1 ratio in buffered biofilm medium in a 96-well active attachment model. The single- and dual-species biofilms were grown under either constantly neutral pH or pH-cycling conditions. The latter includes two cycles of 8 h neutral pH and 16 h pH 5.5, used to mimic cariogenic condition. The 48 h biofilms were analysed for the viable cell counts, lactate and HP production. The last two measurements were carried out after incubating the 48 h biofilms in buffers supplemented with 1% glucose (pH 7.0) for 4 h. The results showed that S. oligofermentans inhibited the growth of S. mutans in dual-species biofilms under both tested pH conditions. The lactic acid production of dual-species biofilms was significantly lower than that of single-species S. mutans biofilms. Moreover, dual-species and single-species S. oligofermentans biofilms grown under pH-cycling conditions (with a 16 h low pH period) produced a significantly higher amount of HP than those grown under constantly neutral pH. In conclusion, S. oligofermentans inhibited S. mutans in biofilms not only under neutral pH, but also under pH-cycling conditions, likely through HP production. S. oligofermentans may be a compelling probiotic candidate against caries.

  9. THE PATHOLOGIC EFFECTS OF STREPTOCOCCI FROM CASES OF POLIOMYELITIS AND OTHER SOURCES

    Science.gov (United States)

    Bull, Carroll G.

    1917-01-01

    Streptococci cultivated from the tonsils of thirty-two cases of poliomyelitis were used to inoculate various laboratory animals. In no case was a condition induced resembling poliomyelitis clinically or pathologically in guinea pigs, dogs, cats, rabbits, or monkeys. On the other hand, a considerable percentage of the rabbits and a smaller percentage of some of the other animals developed lesions due to streptococci. These lesions consisted of meningitis, meningo-encephalitis, abscess of the brain, arthritis, tenosynovitis, myositis, abscess of the kidney, endocarditis, pericarditis, and neuritis. No distinction in the character or frequency of the lesions could be determined between the streptococci derived from poliomyelitic patients and from other sources. Streptococci isolated from the poliomyelitic brain and spinal cord of monkeys which succumbed to inoculation with the filtered virus failed to induce in monkeys any paralysis or the characteristic histological changes of poliomyelitis. These streptococci are regarded as secondary bacterial invaders of the nervous organs. Monkeys which have recovered from infection with streptococci derived from cases of poliomyelitis are not protected from infection with the filtered virus, and their blood does not neutralize the filtered virus in vitro. We have failed to detect any etiologic or pathologic relationship between streptococci and epidemic poliomyelitis in man or true experimental poliomyelitis in the monkey. PMID:19868109

  10. Group F streptococci in the pharynx: pathogens or innocent bystanders?

    Science.gov (United States)

    Schwartz, R H; McCoy, P; Hayden, G F; Hallas, G

    1986-08-01

    beta-Hemolytic streptococci (BHS) of Lancefield group F were isolated in moderate to heavy growth from throat cultures taken from 46 children and adolescents with symptomatic pharyngitis. In most instances, oxygen deprivation by means of an anaerobe jar was required for these beta-hemolytic organisms to grow. In relation to a comparison group of children with throat cultures positive for group A BHS, children with group F isolates were more likely to be adolescents and less likely to have fever and cervical adenopathy. It appears that group F BHS are not a major cause of nonepidemic pharyngitis in the pediatric age group. More precise determination of how commonly these organisms cause pharyngitis will require either comparison of isolation rates of group F BHS from the throats of both sick and well children, or further elucidation of the serologic response to these organisms so as to distinguish invasive infection from asymptomatic carriage.

  11. Susceptibility to β-lactams in β-hemolytic streptococci.

    Science.gov (United States)

    Bonofiglio, Laura; Gagetti, Paula; García Gabarrot, Gabriela; Kaufman, Sara; Mollerach, Marta; Toresani, Inés; Vigliarolo, Laura; von Specht, Martha; Lopardo, Horacio A

    2018-03-13

    Group A (GAS), B (GBS), C (GCS) and G (GGS) β-hemolytic streptococci are important human pathogens. They cause infections of different severity and frequency. Nowadays, after 70 years of use, penicillin is still universally active against GAS, GCS and GGS. However, therapeutic failures have been recorded in 2-28% of pharyngitis cases (median: 12%) attributable to different causes. By contrast, some GBS with reduced susceptibility to penicillin have been described, especially in Japan. In this group of bacteria, it is important to highlight that confirmation by reference methods is mandatory when decreased susceptibility to penicillin is suspected as well as checked for the detection of the mechanisms involved. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Antibacterial activity of cinnamon ethanol extract (cinnamomum burmannii) and its application as a mouthwash to inhibit streptococcus growth

    Science.gov (United States)

    Waty, Syahdiana; Suryanto, Dwi; Yurnaliza

    2018-03-01

    Cinnamon bark has been commonly used as spicy and traditional medicine. It contains several antibacterial compounds such as flavonoids, saponins, and cinnamaldehyde. Several studies have been done to know the antibacterial effect on bacteria such as Streptococcus in vitro. This study aimed to examine the antibacterial activity of cinnamon ethanol extract against Streptococcus and its application as mouthwash to inhibit the bacteria. The cinnamon bark was macerated followed by extracted in 80% ethanol. Bacterial samples were isolated from dental plaque of patients visiting dental clinic drg. Syahdiana Waty in Medan, North Sumatra. The isolates were identified using Vitek 2 compact. Secondary metabolites were detected using previously described method. Antibacterial assay was done at extract concentration of 6.25%, 12.5%, and 25%. The result showed that alkaloids, flavonoids, saponins, and glycoside were detected in the extract. Nine bacterial species were identified as Streptococcus mitis, S. sanguinis, S. salivarius, S. pluranimalium, S. pneumoniae, S. alactolyticus, Kocuria rosea, Kocuria kristinae, and Spingomonas paucimolis. It showed that the extract of Cinnamon bark significantly inhibited Streptococcus growth, and it was effective as mouthwash.

  13. Stress responses in Streptococcus species and their effects on the host.

    Science.gov (United States)

    Nguyen, Cuong Thach; Park, Sang-Sang; Rhee, Dong-Kwon

    2015-11-01

    Streptococci cause a variety of diseases, such as dental caries, pharyngitis, meningitis, pneumonia, bacteremia, endocarditis, erysipelas, and necrotizing fasciitis. The natural niche of this genus of bacteria ranges from the mouth and nasopharynx to the skin, indicating that the bacteria will inevitably be subjected to environmental changes during invasion into the host, where it is exposed to the host immune system. Thus, the Streptococcus-host interaction determines whether bacteria are cleared by the host's defenses or whether they survive after invasion to cause serious diseases. If this interaction was to be deciphered, it could aid in the development of novel preventive and therapeutic agents. Streptococcus species possess many virulent factors, such as peroxidases and heat-shock proteins (HSPs), which play key roles in protecting the bacteria from hostile host environments. This review will discuss insights into the mechanism(s) by which streptococci adapt to host environments. Additionally, we will address how streptococcal infections trigger host stress responses; however, the mechanism by which bacterial components modulate host stress responses remains largely unknown.

  14. Septicemia with Streptococcus pseudopneumoniae

    DEFF Research Database (Denmark)

    Fuursted, Kurt; Littauer, Pia Jeanette; Greve, Thomas

    2016-01-01

    Streptococcus pseudopneumoniae was described in 2004 as a new human pathogen, acknowledged in a range of clinical infections typically associated to the respiratory tract. This report demonstrates that S. pseudopneumoniae has the potential to cause invasive infection. In blood cultures from three...... and the antibiogram and resistome revealed no antibiotic resistance....

  15. Bacteremia with Streptococcus pneumoniae

    DEFF Research Database (Denmark)

    Christensen, J S; Jensen, T G; Kolmos, H J

    2012-01-01

    We conducted a hospital-based cohort study among adult patients with first-time Streptococcus pneumoniae bacteremia (SPB) from 2000 through 2008. Patients were identified in a population-based bacteremia database and followed up for mortality through the Danish Civil Registration System (CRS...

  16. Improved method for rapid and accurate isolation and identification of Streptococcus mutans and Streptococcus sobrinus from human plaque samples.

    Science.gov (United States)

    Villhauer, Alissa L; Lynch, David J; Drake, David R

    2017-08-01

    Mutans streptococci (MS), specifically Streptococcus mutans (SM) and Streptococcus sobrinus (SS), are bacterial species frequently targeted for investigation due to their role in the etiology of dental caries. Differentiation of S. mutans and S. sobrinus is an essential part of exploring the role of these organisms in disease progression and the impact of the presence of either/both on a subject's caries experience. Of vital importance to the study of these organisms is an identification protocol that allows us to distinguish between the two species in an easy, accurate, and timely manner. While conducting a 5-year birth cohort study in a Northern Plains American Indian tribe, the need for a more rapid procedure for isolating and identifying high volumes of MS was recognized. We report here on the development of an accurate and rapid method for MS identification. Accuracy, ease of use, and material and time requirements for morphological differentiation on selective agar, biochemical tests, and various combinations of PCR primers were compared. The final protocol included preliminary identification based on colony morphology followed by PCR confirmation of species identification using primers targeting regions of the glucosyltransferase (gtf) genes of SM and SS. This method of isolation and identification was found to be highly accurate, more rapid than the previous methodology used, and easily learned. It resulted in more efficient use of both time and material resources. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Homology among tet determinants in conjugative elements of streptococci

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.D.; Hazum, S.; Guild, W.R.

    1981-10-01

    A mutation to tetracycline sensitivity in a resistant strain of Streptococcus pneumoniae was shown by several criteria to be due to a point mutation in the conjugative o(cat-tet) element found in the chromosomes of strains derived from BM6001, a clinical strain resistant to tetracycline and chloramphenicol. Strains carrying the mutation were transformed back to tetracycline resistance with the high efficiency of a point marker by donor deoxyribonucleic acids from its ancestral strain and from nine other clinical isolates of pneumococcus and by deoxyribonucleic acids from Group D Streptococcus faecalis and Group B Streptococcus agalactiae strains that also carry conjugative tet elements in their chromosomes. It was not transformed to resistance by tet plasmid deoxyribonucleic acids from either gram-negative or gram-positive species, except for one that carried transposon TN916, the conjugative tet element present in the chromosomes of some S. faecalis strains. The results showed that the tet determinants in conjugative elements of several streptococcal species share a high degree of deoxyribonucleic acid sequence homology and suggested that they differ from other tet genes.

  18. Streptococcus suis, an emerging drug-resistant animal and human pathogen

    Directory of Open Access Journals (Sweden)

    Claudio ePalmieri

    2011-11-01

    Full Text Available Streptococcus suis, a major porcine pathogen, has been receiving growing attention not only for its role in severe and increasingly reported infections in humans, but also for its involvement in drug resistance. Recent studies and the analysis of sequenced genomes have been providing important insights into the S. suis resistome, and have resulted in the identification of resistance determinants for tetracyclines, macrolides, aminoglycosides, chloramphenicol, antifolate drugs, streptothricin, and cadmium salts. Resistance gene-carrying genetic elements described so far include integrative and conjugative elements, transposons, genomic islands, phages, and chimeric elements. Some of these elements are similar to those reported in major streptococcal pathogens such as Streptococcus pyogenes, Streptococcus pneumoniae, and Streptococcus agalactiae and share the same chromosomal insertion sites. The available information strongly suggests that S. suis is an important antibiotic resistance reservoir that can contribute to the spread of resistance genes to the above-mentioned streptococci. S. suis is thus a paradigmatic example of possible intersections between animal and human resistomes.

  19. Streptococcus sanguinis as an opportunistic bacteria in human oral cavity: Adherence, colonization, and invasion

    Directory of Open Access Journals (Sweden)

    Hening Tjaturina Pramesti

    2017-08-01

    Full Text Available Streptococcus sanguinis (formerly S. sanguis is a Gram-positive, facultative anaerobe,  nonmotile , normal  inhabitant of the human oral cavity, and  a member of  the viridans group of streptococci. Among the streptococcus, S. sanguinis is a  primary colonizer in the human tooth surface or it is recognize as a ‘pioneer’ by forming dental plaque. The aim of this paper is to review the role of Streptococcus sanguinis  in the adherence to and  invasion of  human tissues.  S. sanguinis  has been reported  that it is associated  with healthy  tooth  surfaces  but not with caries. S. sanguinis  tend to involved in an interspecies interactions with Streptococcus mutans, which is known as  competition/coexistence within dental biofilm.  In their colonization, this bacteria used enzyme sortase A (SrtA to cleave  LPXTG-containing proteins sequence and  anchored  the  cell wall, while virulence factors  in infective endocarditis  involved housekeeping functions such as cell wall synthesis, amino acid and nucleic acid synthesis, and the ability to survive under anaerobic conditions.

  20. Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Natalie Maricic

    2016-01-01

    Full Text Available Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials.

  1. Comparative short-term in vitro analysis of mutans streptococci adhesion on esthetic, nickel-titanium, and stainless-steel arch wires.

    Science.gov (United States)

    Kim, In-Hye; Park, Hyo-Sang; Kim, Young Kyung; Kim, Kyo-Han; Kwon, Tae-Yub

    2014-07-01

    To test the hypothesis that there are no differences in mutans streptococci (MS) adhesion between esthetic and metallic orthodontic arch wires based on their surface characteristics. Surface roughness (Ra) and apparent surface free energy (SFE) were measured for six wires-four esthetic, one nickel-titanium (NiTi), and one stainless-steel (SS)-using profilometry and dynamic contact angle analysis, respectively. The amount of MS (Streptococcus mutans and Streptococcus sobrinus) adhering to the wires was quantified using the colony-counting method. The surfaces, coating layers, and MS adhesion were also observed by scanning electron microscopy. Statistical significance was set at P wires were significantly different from one another depending on the coating method (P wire showed the highest SFE, followed by the SS wire and then the four esthetic wires. The NiTi wires produced a significantly higher MS adhesion than did the SS wires (P wires showed significantly lower MS adhesions than did the NiTi wire (P < .05). Pearson correlation analyses found moderate significant positive correlations between the SFE and the S mutans and S sobrinus adhesions (r  =  .636/.427, P < .001/P  =  .001, respectively). The hypothesis is rejected. This study indicates that some esthetic coatings on NiTi alloy might reduce MS adhesion in vitro in the short term.

  2. Correlation between dental caries experience and mutans streptococci counts using saliva and plaque as microbial risk indicators in 3-8 year old children. A cross Sectional study.

    Science.gov (United States)

    Nanda, Jasmine; Sachdev, Vinod; Sandhu, Meera; Deep-Singh-Nanda, Kanwar

    2015-02-01

    Determination of the relative amounts of mutans streptococcus in both saliva and plaque and to study its correlation with dental caries in children. The study comprised of 60 children aged 3-8 years divided into 2 groups (30 children in each): Group A- Children with more than 4 carious teeth and Group B- Children without caries. Saliva and plaque was collected from children of both the groups with the help of Dentocult SM strip test kit (Orion Diagnostic). Following incubation, mutans streptococcus scores (from 0 to 3) in each individual was evaluated and compared between both the groups. On comparing the two groups, mean ± SD of saliva score and plaque score was 2.40 ± 0.675 and 2.40 ± 0.621 respectively in group A, whereas it was 0.60 ± 0.498 and 0.83 ± 0.531 in children of group B showing a significant correlation (p = Key words:Mutans streptococci, dentocult, dental caries.

  3. Effect of storage temperature on Streptococcus mutans viability

    Directory of Open Access Journals (Sweden)

    Ana Lídia Soares COTA

    2018-04-01

    Full Text Available Abstract Introduction Proper storage conditions and maintenance of viable biological material plays an important role in microbiological research, allowing for the opportunity to conduct future studies. Objective To evaluate the viability of Streptococcus mutans strains that were previously grown and stored under different temperatures for approximately eight years. Material and method In this study, we evaluated 393 bacterial isolates that were stored in a freezer at -80°C (G1 and 200 isolates stored in a freezer at -20°C (G2. Aliquots of each sample were plated on blood agar and mitis-salivarius bacitracin sucrose agar-solidified medium. After incubating under microaerophilic conditions in an incubator at 37°C for 72 hours, the presence, morphology and purity of bacterial growth was observed. The data were analyzed by means of descriptive statistics. Result Microbial viability was observed in almost all samples (99.7% in G1, whereas all isolates stored at -20°C were considered inviable. Conclusion The viability of S. mutans is influenced by the storage temperature of the samples, and the strains remain viable when stored under ideal temperature conditions (-80°C, even when stored for a long period of time.

  4. Erythromycin-resistant genes in group A β-haemolytic Streptococci in Chengdu, Southwestern China

    Directory of Open Access Journals (Sweden)

    W Zhou

    2014-01-01

    Full Text Available Context: The management of Group A β-haemolytic Streptococci (Streptococcus pyogenes or GAS infection include the use of penicillins, cephalosporins or macrolides for treatment. A general increase in macrolides resistance in GAS has been observed in recent years. Differences in rates of resistance to these agents have existed according to geographical location and investigators. Aims: To investigate the antibiotic pattern and erythromycin-resistant genes of GAS isolates associated with acute tonsillitis and scarlet fever in Chengdu, southwestern China. Settings and Design: To assess the macrolide resistance, phenotype, and genotypic characterization of GAS isolated from throat swabs of children suffering from different acute tonsillitis or scarlet fever between 2004 and 2011 in the city of Chengdu, located in the southwestern region of China. Materials and Methods: Minimal inhibitory concentration with seven antibiotics was performed on 127 GAS isolates. Resistance phenotypes of erythromycin-resistant GAS isolates were determined by the double-disk test. Their macrolide-resistant genes (mefA, ermB and ermTR were amplified by PCR. Results: A total of 98.4% (125/127 of the isolates exhibited resistance to erythromycin, clindamycin and tetracycline. All isolates were sensitive to penicillin G and cefotaxime. Moreover, 113 ermB-positive isolates demonstrating the cMLS phenotype of erythromycin resistance were predominant (90.4% and these isolates showed high-level resistance to both erythromycin and clindamycin (MIC 90 > 256 μg/ml; 12 (9.6% isolates demonstrating the MLS phenotype of erythromycin resistance carried the mefA gene, which showed low-level resistance to both erythromycin (MIC 90 = 8 μg/ml and clindamycin (MIC 90 = 0.5 μg/ml; and none of the isolates exhibited the M phenotype. Conclusions: The main phenotype is cMLS, and the ermB gene code is the main resistance mechanism against macrolides in GAS. Penicillin is the most beneficial

  5. Molecular characterization of Streptococcus agalactiae and Streptococcus uberis isolates from bovine milk.

    Science.gov (United States)

    Shome, Bibek Ranjan; Bhuvana, Mani; Mitra, Susweta Das; Krithiga, Natesan; Shome, Rajeswari; Velu, Dhanikachalam; Banerjee, Apala; Barbuddhe, Sukhadeo B; Prabhudas, Krishnamshetty; Rahman, Habibar

    2012-12-01

    Streptococci are one among the major mastitis pathogens which have a considerable impact on cow health, milk quality, and productivity. The aim of the present study was to investigate the occurrence and virulence characteristics of streptococci from bovine milk and to assess the molecular epidemiology and population structure of the Indian isolates using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Out of a total of 209 bovine composite milk samples screened from four herds (A-D), 30 Streptococcus spp. were isolated from 29 milk samples. Among the 30 isolates, species-specific PCR and partial 16S rRNA gene sequence analysis identified 17 Streptococcus agalactiae arising from herd A and 13 Streptococcus uberis comprising of 5, 7, and 1 isolates from herds B, C, and D respectively. PCR based screening for virulence genes revealed the presence of the cfb and the pavA genes in 17 and 1 S. agalactiae isolates, respectively. Similarly, in S. uberis isolates, cfu gene was present in six isolates from herd C, the pau A/skc gene in all the isolates from herds B, C, and D, whereas the sua gene was present in four isolates from herd B and the only isolate from herd D. On MLST analysis, all the S. agalactiae isolates were found to be of a novel sequence type (ST), ST-483, reported for the first time and is a single locus variant of the predicted subgroup founder ST-310, while the S. uberis isolates were found to be of three novel sequence types, namely ST-439, ST-474, and ST-475, all reported for the first time. ST-474 was a double locus variant of three different STs of global clonal complex ST-143 considered to be associated with clinical and subclinical mastitis, but ST-439 and ST-475 were singletons. Unique sequence types identified for both S. agalactiae and S. uberis were found to be herd specific. On PFGE analysis, identical or closely related restriction patterns for S. agalactiae ST-483 and S. uberis ST-439 in herds A and B

  6. Non-group A streptococci in the pharynx. Pathogens or innocent bystanders?

    Science.gov (United States)

    Hayden, G F; Murphy, T F; Hendley, J O

    1989-07-01

    To determine whether beta-hemolytic streptococci from groups other than A are an important cause of sporadic pharyngitis in children. Cross-sectional, case-referent survey. General pediatric clinic at a military base in Ohio. One hundred fifty children with symptomatic pharyngitis and 150 controls matched for age and time of presentation over a 20-month study period. None. Anaerobic culture technique was used to improve isolation of beta-hemolytic streptococci. Group A beta-hemolytic streptococci were detected significantly more often among the ill children than among the controls (39% vs 16%, respectively). In contrast, non-group A beta-hemolytic streptococci were isolated in similar frequency from the ill and control children (17% vs 21%, respectively). Non-group A beta-hemolytic streptococci from groups B, C, F, and G were each isolated in similar frequency among the ill and control children. The isolation rate of non-group A organisms increased with age among both patients and controls. Non-group A beta-hemolytic streptococci seemed not to be an important cause of sporadic pharyngitis in this pediatric population.

  7. Antibacterial activity of ethanolic extract of Myrtus communis. L leaves against salivary Mutans streptococci

    International Nuclear Information System (INIS)

    AlAnbori, Dalia K.A; AlNimer, Marwan S.M; AlWeheb, Athraa M

    2008-01-01

    The aim of this study was to evaluate the efficacy of ethanolic extract of Myrtus communis (myrtle) leaves in the selective reduction of Mutans streptococci count in saliva compared to chlorhexidine through in vitro and in vivo experiments. Ethanolic extract (2%) was prepared and screened by UV-visible spectrophotometer to detect peaks of active compounds. The minimum inhibitory concentrations (MICs) of myrtle extract as well as chlorhexidine (0.12%) were determined against Mutans streptococci isolated from human saliva and identified bacteriologically in vivo experiments, the effect of single mouth rinse of myrtle extract or chlorhexidine was investigated against the number of colony forming unit (CFU) of Mutans streptococci for two hours after rinse. The results showed the presence of one large peak at λ266.5 nm and a small one at λ672 of the extract in UV-visible spectra suggesting the presence of flavanoid. The MIC of myrtle was 106.6 μg/mL compared with 3.3 μg/mL of chlorhexidine. Single mouth rinse of myrtle extract significantly reduced the number of CFU of salivary Mutans streptococci but its effect was significantly less than that of chlorhexidine. It was concluded that the antibacterial effect of myrtle on Mutans streptococci was due to its flavanoid content. Therefore, ethanolic extract of myrtle could be a potential remedy for the prevention of colonization by Mutans streptococci thereby preventing or retarding development of dental caries. (author)

  8. Streptococcus caviae sp. nov., isolated from guinea pig faecal samples.

    Science.gov (United States)

    Palakawong Na Ayudthaya, Susakul; Hilderink, Loes J; Oost, John van der; Vos, Willem M de; Plugge, Caroline M

    2017-05-01

    A novel cellobiose-degrading and lactate-producing bacterium, strain Cavy grass 6T, was isolated from faecal samples of guinea pigs (Cavia porcellus). Cells of the strain were ovalshaped, non-motile, non-spore-forming, Gram-stain-positive and facultatively anaerobic. The strain gr at 25-40 °C (optimum 37 °C) and pH 4.5-9.5 (optimum 8.0). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Cavy grass 6T belongs to the genus Streptococcus with its closest relative being Streptococcus devriesei CCUG 47155T with only 96.5 % similarity. Comparing strain Cavy grass 6T and Streptococcus devriesei CCUG 47155T, average nucleotide identity and level of digital DNA-DNA hybridization dDDH were only 86.9 and 33.3 %, respectively. Housekeeping genes groEL and gyrA were different between strain Cavy grass 6T and other streptococci. The G+C content of strain Cavy grass 6T was 42.6±0.3 mol%. The major (>10 %) cellular fatty acids of strain Cavy grass 6T were C16:0, C20 : 1ω9c and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). Strain Cavy grass 6T ferment a range of plant mono- and disaccharides as well as polymeric carbohydrates, including cellobiose, dulcitol, d-glucose, maltose, raffinose, sucrose, l-sorbose, trehalose, inulin and dried grass extract, to lactate, formate, acetate and ethanol. Based on phylogenetic and physiological characteristics, Cavy grass 6T can be distinguished from other members of the genus Streptococcus. Therefore, a novel species of the genus Streptococcus, family Streptococcaceae, order Lactobacillales is proposed, Streptococcuscaviae sp. nov. (type strain Cavy grass 6T=TISTR 2371T=DSM 102819T).

  9. Virulence Factors of Streptococcus mutans.

    Science.gov (United States)

    1986-08-01

    763512/715242 Final Report U VIRULENCE FACTORS OF STREPTOCOCCUS MUTANS U Samuel Rosen Department of Oral Biology For the Period April 1, 1983 - June 30...00 FINAL REPORT VIRULENCE FACTORS OF STREPTOCOCCUS MUTANS Sam Rosen, Irving Shklair, E. X. Beck and F. M. Beck Ohio State University Columbus,Oh and...206-212. Johnson CP, Gorss S, Hillman JD (1978). Cariogenic properties of LDH deficient mutants of streptococcus mutans . J Dent Res 57, Special Issue

  10. [The electron microscopic observation of the effect of monoclonal antibody on the form and structure of mutans streptococci OMZ176].

    Science.gov (United States)

    Wen, L; Yue, S

    1996-01-01

    The effect of monoclonal antibody on the form and structure of Mutans Streptococci OMZ176 was studied. The result showed that a great number of Mutans Streptococci OMZ176 was agglutianated after treating with monoclonal antibody prepared by a cell wall protein antigen (molecular weight 220 kd) of Mutans Streptococci OMZ176. Bacterial cells were swollen obviously. The gap between cell wall and cytoplasmic was widened. The electronic density of cell plasm was greatly decreased.

  11. Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae.

    Science.gov (United States)

    Maricic, Natalie; Anderson, Erica S; Opipari, AnneMarie E; Yu, Emily A; Dawid, Suzanne

    2016-01-26

    Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus) in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials. Successful colonization of a polymicrobial host surface is a prerequisite for the subsequent development of disease for many bacterial pathogens. Bacterial factors that directly inhibit the growth of neighbors

  12. Phenotypic and genotypic antimicrobial susceptibility pattern of Streptococcus spp. isolated from cases of clinical mastitis in dairy cattle in Poland.

    Science.gov (United States)

    Kaczorek, E; Małaczewska, J; Wójcik, R; Rękawek, W; Siwicki, A K

    2017-08-01

    Mastitis of dairy cattle is one of the most frequently diagnosed diseases worldwide. The main etiological agents of mastitis are bacteria of the genus Streptococcus spp., in which several antibiotic resistance mechanisms have been identified. However, detailed studies addressing this problem have not been conducted in northeastern Poland. Therefore, the aim of our study was to analyze, on phenotypic and genotypic levels, the antibiotic resistance pattern of Streptococcus spp. isolated from clinical cases of mastitis from dairy cattle in this region of Poland. The research was conducted using 135 strains of Streptococcus (Streptococcus uberis, n = 53; Streptococcus dysgalactiae, n = 41; Streptococcus agalactiae, n = 27; other streptococci, n = 14). The investigation of the antimicrobial susceptibility to 8 active substances applied in therapy in the analyzed region, as well as a selected bacteriocin (nisin), was performed using the minimum inhibitory concentration method. The presence of selected resistance genes (n = 14) was determined via PCR. We also investigated the correlation between the presence of resistance genes and the antimicrobial susceptibility of the examined strains in vitro. The highest observed resistance of Streptococcus spp. was toward gentamicin, kanamycin, and tetracycline, whereas the highest susceptibility occurred toward penicillin, enrofloxacin, and marbofloxacin. Additionally, the tested bacteriocin showed high efficacy. The presence of 13 analyzed resistance genes was observed in the examined strains [gene mef(A) was not detected]. In most strains, at least one resistance gene, mainly responsible for resistance to tetracyclines [tet(M), tet(K), tet(L)], was observed. However, a relationship between the presence of a given resistance gene and antimicrobial susceptibility on the phenotypic level was not always observed. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  13. Genetic Transformation of Streptococcus mutans

    OpenAIRE

    Perry, Dennis; Kuramitsu, Howard K.

    1981-01-01

    Three strains of Streptococcus mutans belonging to serotypes a, c, and f were transformed to streptomycin resistance by deoxyribonucleic acids derived from homologous and heterologous streptomycin-resistant strains of S. mutans and Streptococcus sanguis strain Challis. Homologous transformation of S. mutans was less efficient than heterologous transformation by deoxyribonucleic acids from other strains of S. mutans.

  14. Viridans streptococci Intracranial Abscess Masquerading as Metastatic Disease

    Directory of Open Access Journals (Sweden)

    Brandon Ruderman

    2018-01-01

    Full Text Available History of present illness: A 64-year-old woman with a remote history of breast cancer presented to the emergency department with one day of worsening right-sided weakness and headaches. She had been seen two weeks prior for similar symptoms and underwent unenhanced brain computed tomography (CT, which revealed a left parietal mass suspected to represent new metastatic disease. The patient presented on this visit not only with weakness of her right upper and lower extremity, but was found to be febrile, tachycardic and exhibiting lethargy. Peripheral white blood cell count (WBC was 27.1 (x109/L. Given her rapidly declining clinical course and expected time to complete magnetic resonance imaging (MRI of the brain, the decision was made to first perform an emergent contrast-enhanced brain CT to further evaluate the mass. The contrast-enhanced brain CT revealed a large rim-enhancing left parietal lesion (Figures 1 and 2. Significant findings: A non-contrast CT (Figure 1 revealed a large hypoattenuating left parietal lesion. When the CT was enhanced with intravenous contrast (Figure 2, the same lesion showed peripheral rim enhancement, suggestive of a brain abscess. Discussion: Intracranial abscess is a rare yet potentially devastating disease process that can often be difficult to diagnosis, with an incidence of about 0.4-0.9 cases per 100,000 people.1 Mortality rates are about 15% within the past decade, but can increase up to 85% if the abscess ruptures. The most common mechanisms for formation of intracranial abscesses include direct spread from local infections (odontogenic infections or sinusitis, hematogenous spread (congenital heart disease, endocarditis, dental procedures, or intrapulmonary shunting, or penetrating trauma.2 Intracranial abscesses are more likely to occur in severely immunosuppressed patients, after neurosurgical procedures, or in head trauma. About 32%-60% of brain abscesses are polymicrobial, but Viridans streptococci, a

  15. Transmission of mutans streptococci in mother-child pairs

    Directory of Open Access Journals (Sweden)

    S G Damle

    2016-01-01

    Full Text Available Background & objectives: Dental caries is an infectious, transmissible disease. Maternal transfer of mutans streptococci (MS has been a subject of research. The aim of this study was to evaluate the transmission of MS from mother to children through genetic analysis. Methods: Thirty mother-child pairs were included and divided into three groups according to the age of the children. Saliva samples were collected and MS colonies from each mother-child pair were isolated. After inoculation and incubation, MS colonies were submitted to amplification technique by polymerase chain reaction (PCR for identification and arbitrarily primed PCRs (AP-PCRs to determine various MS genotypes. Results: From birth to six months of age, 30 per cent of children exhibited MS colonization, and by the age of 30 months, 100 per cent harboured the bacteria (P < 0.001. Factors associated with MS colonization were eruption of teeth (P < 0.001, feeding habits with mean colony count being significantly lower in breast-fed as compared to bottle-fed children (P < 0.001 and a significant association between mean MS count of child and mother′s practice of sharing spoon with child (P < 0.001. The AP-PCR fingerprinting profile analysis showed 17 MS groups (clusters containing identical or highly related isolates in mother-child pairs with a high level of similarity (77.27 %. Interpretation & conclusions: The presence of matching MS genotypes suggested vertical transmission from mothers to children. Feeding habits, gum cleaning and number of erupted teeth in children had significant effect on MS colonization. There is a need to develop strategies to present MS colonization in children.

  16. Meningitis por Streptococcus suis

    OpenAIRE

    Geffner Sclarsky, D. E.; Moreno Muñoz, R.; Campillo Alpera, Mª.S.; Pardo Serrano, F.J.; Gómez Gómez, A.; Martínez-Lozano, Mª.D.

    2001-01-01

    La infección humana por Streptococcus suis (S. suis) es una zoonosis, con un riesgo ocupacional conocido y que suele presentarse como meningitis purulenta, que tiene baja mortalidad y frecuentes secuelas de hipoacusia y ataxia. Se han publicado menos de 150 casos humanos desde el informe original de hace 30 años. Hay una reconocida distribución geográfica viviendo la mayoría de los afectados en el norte de Europa y el sudeste Asiático. En España se han comunicado dos pacientes con enfermedad ...

  17. The efficacy of chlorhexidine gel in reduction of Streptococcus mutans and Lactobacillus species in patients treated with radiation therapy

    International Nuclear Information System (INIS)

    Epstein, J.B.; McBride, B.C.; Stevenson-Moore, P.; Merilees, H.; Spinelli, J.

    1991-01-01

    Xerostomia may develop in patients with cancer who receive radiotherapy that includes the salivary glands in the field. These patients are at high risk of rampant dental caries. Streptococcus mutans and Lactobacillus species have been associated with dental caries. Quantitative counts of these organisms demonstrated high caries risk due to streptococci in 66% and due to lactobacilli in 100% of patients studied. Use of chlorhexidine rinse was shown to reduce S. mutans counts 1.1 logs and lactobacilli 1.1 logs. The use of chlorhexidine gel resulted in a reduction of S. mutans 1.2 logs and lactobacilli 2.2 logs. In the subjects using the rinse, caries risk due to streptococci was reduced to low levels in 44% and due to lactobacilli in only one subject, with reduction to moderate risk in one third and no change in risk in the remaining patients. The use of chlorhexidine gel was found to reduce the caries risk associated with streptococci to low levels in all patients, and the risk associated with lactobacilli to low and moderate risk in two thirds of patients

  18. The efficacy of chlorhexidine gel in reduction of Streptococcus mutans and Lactobacillus species in patients treated with radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, J.B.; McBride, B.C.; Stevenson-Moore, P.; Merilees, H.; Spinelli, J. (Cancer Control Agency of British Columbia, Vancouver (Canada))

    1991-02-01

    Xerostomia may develop in patients with cancer who receive radiotherapy that includes the salivary glands in the field. These patients are at high risk of rampant dental caries. Streptococcus mutans and Lactobacillus species have been associated with dental caries. Quantitative counts of these organisms demonstrated high caries risk due to streptococci in 66% and due to lactobacilli in 100% of patients studied. Use of chlorhexidine rinse was shown to reduce S. mutans counts 1.1 logs and lactobacilli 1.1 logs. The use of chlorhexidine gel resulted in a reduction of S. mutans 1.2 logs and lactobacilli 2.2 logs. In the subjects using the rinse, caries risk due to streptococci was reduced to low levels in 44% and due to lactobacilli in only one subject, with reduction to moderate risk in one third and no change in risk in the remaining patients. The use of chlorhexidine gel was found to reduce the caries risk associated with streptococci to low levels in all patients, and the risk associated with lactobacilli to low and moderate risk in two thirds of patients.

  19. Population and Whole Genome Sequence Based Characterization of Invasive Group A Streptococci Recovered in the United States during 2015

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    Sopio Chochua

    2017-09-01

    Full Text Available Group A streptococci (GAS are genetically diverse. Determination of strain features can reveal associations with disease and resistance and assist in vaccine formulation. We employed whole-genome sequence (WGS-based characterization of 1,454 invasive GAS isolates recovered in 2015 by Active Bacterial Core Surveillance and performed conventional antimicrobial susceptibility testing. Predictions were made for genotype, GAS carbohydrate, antimicrobial resistance, surface proteins (M family, fibronectin binding, T, R28, secreted virulence proteins (Sda1, Sic, exotoxins, hyaluronate capsule, and an upregulated nga operon (encodes NADase and streptolysin O promoter (Pnga3. Sixty-four M protein gene (emm types were identified among 69 clonal complexes (CCs, including one CC of Streptococcus dysgalactiae subsp. equisimilis. emm types predicted the presence or absence of active sof determinants and were segregated into sof-positive or sof-negative genetic complexes. Only one “emm type switch” between strains was apparent. sof-negative strains showed a propensity to cause infections in the first quarter of the year, while sof+ strain infections were more likely in summer. Of 1,454 isolates, 808 (55.6% were Pnga3 positive and 637 (78.9% were accounted for by types emm1, emm89, and emm12. Theoretical coverage of a 30-valent M vaccine combined with an M-related protein (Mrp vaccine encompassed 98% of the isolates. WGS data predicted that 15.3, 13.8, 12.7, and 0.6% of the isolates were nonsusceptible to tetracycline, erythromycin plus clindamycin, erythromycin, and fluoroquinolones, respectively, with only 19 discordant phenotypic results. Close phylogenetic clustering of emm59 isolates was consistent with recent regional emergence. This study revealed strain traits informative for GAS disease incidence tracking, outbreak detection, vaccine strategy, and antimicrobial therapy.

  20. Neoraudiol, a new isoflavonoid and other antimicrobial constituents from the tuberous root of Neorautanenia mitis (A. Rich Verdcourt

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    A.A. Lasisi

    2015-07-01

    Full Text Available A bioassay-directed fractionation of n-hexane and chloroform extracts of the tuberous roots of Neorautanenia mitis resulted in the isolation of a new isoflavonoid, named neoraudiol (1 and five known compounds: rautandiol A (2, neoduline (3, neotenone (4, pachyrrhizine (5 and 12a-hydroxylrotenone (6. The structure of the new compound was established on the basis of spectroscopic studies and comparison with known compounds. Isolated compounds exhibited broad spectrum antimicrobial activity ranging from 15 to 80 mg/ml, the most significant activity (MIC15.10 ± 0.5 mg/ml was exhibited by neoraudiol. Structure–activity relationship is described.

  1. The enhanced pneumococcal LAMP assay: a clinical tool for the diagnosis of meningitis due to Streptococcus pneumoniae.

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    Dong Wook Kim

    Full Text Available BACKGROUND: Streptococcus pneumoniae is a leading cause of invasive bacterial disease in developed and developing countries. We studied the loop-mediated isothermal amplification (LAMP technique to assess its suitability for detecting S. pneumoniae nucleic acid in cerebrospinal fluid (CSF. METHODOLOGY/PRINCIPAL FINDINGS: We established an improved LAMP assay targeting the lytA gene (Streptococcus pneumoniae [Sp] LAMP. The analytical specificity of the primers was validated by using 32 reference strains (10 Streptococcus and seven non-Streptococcus species plus 25 clinical alpha-hemolytic streptococcal strains, including four S. pneumoniae strains and 21 other strains (3 S. oralis, 17 S. mitis, and one Streptococcus species harboring virulence factor-encoding genes (lytA or ply. Within 30 minutes, the assay could detect as few as 10 copies of both purified DNA and spiked CSF specimens with greater sensitivity than conventional polymerase chain reaction (PCR. The linear determination range for this assay is 10 to 1,000,000 microorganisms per reaction mixture using real-time turbidimetry. We evaluated the clinical sensitivity and specificity of the Sp LAMP assay using 106 randomly selected CSF specimens from children with suspected meningitis in Korea, China and Vietnam. For comparison, CSF specimens were also tested against conventional PCR and culture tests. The detection rate of the LAMP method was substantially higher than the rates of PCR and culture tests. In this small sample, relative to the LAMP assay, the clinical sensitivity of PCR and culture tests was 54.5% and 33.3%, respectively, while clinical specificity of the two tests was 100%. CONCLUSIONS/SIGNIFICANCE: Compared to PCR, Sp LAMP detected S. pneumoniae with higher analytical and clinical sensitivity. This specific and sensitive LAMP method offers significant advantages for screening patients on a population basis and for diagnosis in clinical settings.

  2. Effect of Lectins from Diocleinae Subtribe against Oral Streptococci

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    Edson Holanda Teixeira

    2011-04-01

    Full Text Available Surface colonization is an essential step in biofilm development. The ability of oral pathogens to adhere to tooth surfaces is directly linked with the presence of specific molecules at the bacterial surface that can interact with enamel acquired pellicle ligands. In light of this, the aim of this study was to verify inhibitory and antibiofilm action of lectins from the Diocleinaesubtribe against Streptococcus mutans and Streptococcus oralis. The inhibitory action against planctonic cells was assessed using lectins from Canavaliaensi formis (ConA, Canavalia brasiliensis (ConBr, Canavalia maritima (ConM, Canavalia gladiata (CGL and Canavalia boliviana (ConBol. ConBol, ConBr and ConM showed inhibitory activity on S. mutans growth. All lectins, except ConA, stimulated significantly the growth of S. oralis. To evaluate the effect on biofilm formation, clarified saliva was added to 96-well, flat-bottomed polystyrene plates, followed by the addition of solutions containing 100 or 200 µg/mL of the selected lectins. ConBol, ConM and ConA inhibited the S. mutans biofilms. No effects were found on S. oralis biofilms. Structure/function analysis were carried out using bioinformatics tools. The aperture and deepness of the CRD (Carbohydrate Recognition Domain permit us to distinguish the two groups of Canavalia lectins in accordance to their actions against S. mutans and S. oralis. The results found provide a basis for encouraging the use of plant lectins as biotechnological tools in ecological control and prevention of caries disease.

  3. Quorum Sensing Regulation of Competence and Bacteriocins in Streptococcus pneumoniae and mutans

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    Shanker, Erin; Federle, Michael J.

    2017-01-01

    The human pathogens Streptococcus pneumoniae and Streptococcus mutans have both evolved complex quorum sensing (QS) systems that regulate the production of bacteriocins and the entry into the competent state, a requirement for natural transformation. Natural transformation provides bacteria with a mechanism to repair damaged genes or as a source of new advantageous traits. In S. pneumoniae, the competence pathway is controlled by the two-component signal transduction pathway ComCDE, which directly regulates SigX, the alternative sigma factor required for the initiation into competence. Over the past two decades, effectors of cellular killing (i.e., fratricides) have been recognized as important targets of the pneumococcal competence QS pathway. Recently, direct interactions between the ComCDE and the paralogous BlpRH pathway, regulating bacteriocin production, were identified, further strengthening the interconnections between these two QS systems. Interestingly, a similar theme is being revealed in S. mutans, the primary etiological agent of dental caries. This review compares the relationship between the bacteriocin and the competence QS pathways in both S. pneumoniae and S. mutans, and hopes to provide clues to regulatory pathways across the genus Streptococcus as a potential tool to efficiently investigate putative competence pathways in nontransformable streptococci. PMID:28067778

  4. The Selective Interaction of Pistacia lentiscus Oil vs. Human Streptococci, an Old Functional Food Revisited with New Tools

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    Germano Orrù

    2017-10-01

    Full Text Available Pistacia lentiscus berry oil (LBO represents a typical vegetal product of the Mediterranean basin that has been formally used in traditional cuisine for 100s of years. In addition to its interesting alimentary properties, this product could represent an interesting candidate in the field of research on the study of new anti-infective agents. In fact, in Mediterranean countries, lentisk oil still continues to be widely used in folk medicine for oral and skin affections, in particular, acute gingivitis, pediatric skin infections such as impetigo and foot plaques, and biofilm related infections often associated with Streptococcus spp. Following these observations, we have hypothesized a “lentisk oil-bacteria” interaction, placing particular emphasis on the different Streptococcal species involved in these oral and skin diseases. In accordance with this hypothesis, the use of standard antimicrobial-antibiofilm methods (MIC, MBC, MBIC allowed the interesting behavior of these bacteria to be observed and, in this context, the response to lentisk oil appears to be correlated with the pathogenic profile of the considered microorganism. Two probiotic strains of S. salivarius K12/M18 appeared to be non-sensitive to this product, while a set of five different pathogenic strains (S. agalactiae, S. intermedius, S. mitis, S. mutans, S. pyogenes showed a response that was correlated to the fatty acid metabolic pathway of the considered species. In fact, at different times of bacteria development, selective High Performance Liquid Chromatography analysis of the growth medium containing LBO detected a significant increase in free unsaturated fatty acids (UFAs in particular oleic, palmitic and linoleic acids, which are already known for their antibacterial activity. In this context, we have hypothesized that LBO could be able to modulate the pathogen/probiotic rate in a Streptococcal population using the fatty acid metabolic pathway to help the probiotic

  5. Vaccination against group B streptococcus.

    Science.gov (United States)

    Heath, Paul T; Feldman, Robert G

    2005-04-01

    Streptococcus agalactiae (Group B streptococcus) is an important cause of disease in infants, pregnant women, the elderly and in immunosuppressed adults. An effective vaccine is likely to prevent the majority of infant disease (both early and late onset), as well as Group B streptococcus-related stillbirths and prematurity, to avoid the current real and theoretical limitations of intrapartum antibiotic prophylaxis, and to be cost effective. The optimal time to administer such a vaccine would be in the third trimester of pregnancy. The main limitations on the production of a Group B streptococcus vaccine are not technical or scientific, but regulatory and legal. A number of candidates including capsular conjugate vaccines using traditional carrier proteins such as tetanus toxoid and mutant diphtheria toxin CRM197, as well as Group B streptococcus-specific proteins such as C5a peptidase, protein vaccines using one or more Group B streptococcus surface proteins and mucosal vaccines, have the potential to be successful vaccines. The capsular conjugate vaccines using tetanus and CRM197 carrier proteins are the most advanced candidates, having already completed Phase II human studies including use in the target population of pregnant women (tetanus toxoid conjugate), however, no definitive protein conjugates have yet been trialed. However, unless the regulatory environment is changed specifically to allow the development of a Group B streptococcus vaccine, it is unlikely that one will ever reach the market.

  6. Role of Streptococcus sanguinis sortase A in bacterial colonization.

    Science.gov (United States)

    Yamaguchi, Masaya; Terao, Yutaka; Ogawa, Taiji; Takahashi, Toshihito; Hamada, Shigeyuki; Kawabata, Shigetada

    2006-10-01

    Streptococcus sanguinis, a normal inhabitant of the human oral cavity, has low cariogenicity, though colonization on tooth surfaces by this bacterium initiates aggregation by other oral bacteria and maturation of dental plaque. Additionally, S. sanguinis is frequently isolated from infective endocarditis patients. We investigated the functions of sortase A (SrtA), which cleaves LPXTG-containing proteins and anchors them to the bacterial cell wall, as a possible virulence factor of S. sanguinis. We identified the srtA gene of S. sanguinis by searching a homologous gene of Streptococcus mutans in genome databases. Next, we constructed an srtA-deficient mutant strain of S. sanguinis by insertional inactivation and compared it to the wild type strain. In the case of the mutant strain, some surface proteins could not anchor to the cell wall and were partially released into the culture supernatant. Furthermore, adherence to saliva-coated hydroxyapatite beads and polystyrene plates, as well as adherence to and invasion of human epithelial cells were reduced significantly in the srtA-deficient strain when compared to the wild type. In addition, antiopsonization levels and bacterial survival of the srtA-deficient mutant were decreased in human whole blood. This is the first known study to report that SrtA contributes to antiopsonization in streptococci. Our results suggest that SrtA anchors surface adhesins as well as some proteins that function as antiopsonic molecules as a means of evading the human immune system. Furthermore, they demonstrate that SrtA of S. sanguinis plays important roles in bacterial colonization.

  7. Streptococcus suis infection

    Science.gov (United States)

    Feng, Youjun; Zhang, Huimin; Wu, Zuowei; Wang, Shihua; Cao, Min; Hu, Dan; Wang, Changjun

    2014-01-01

    Streptococcus suis (S. suis) is a family of pathogenic gram-positive bacterial strains that represents a primary health problem in the swine industry worldwide. S. suis is also an emerging zoonotic pathogen that causes severe human infections clinically featuring with varied diseases/syndromes (such as meningitis, septicemia, and arthritis). Over the past few decades, continued efforts have made significant progress toward better understanding this zoonotic infectious entity, contributing in part to the elucidation of the molecular mechanism underlying its high pathogenicity. This review is aimed at presenting an updated overview of this pathogen from the perspective of molecular epidemiology, clinical diagnosis and typing, virulence mechanism, and protective antigens contributing to its zoonosis. PMID:24667807

  8. Chemical and botanical characterization of Chilean propolis and biological activity on cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus

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    Leticia Barrientos

    2013-01-01

    Full Text Available Propolis is a non-toxic natural substance with multiple pharmacological properties including anticancer, antioxidant, fungicidal, antibacterial, antiviral, and anti-inflammatory among others. The aim of this study was to determine the chemical and botanical characterization of Chilean propolis samples and to evaluate their biological activity against the cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. Twenty propolis samples were obtained from beekeeping producers from the central and southern regions of Chile. The botanical profile was determined by palynological analysis. Total phenolic contents were determined using colorimetric assays. Reverse phase HPLC and HPLC-MS were used to determine the chemical composition. The minimum inhibitory concentration (MIC was determined on S. mutans and S. sobrinus. All propolis samples were dominated by structures from native plant species. The characterization by HPLC/MS, evidenced the presence of quercetin, myricetin, kaempferol, rutine, pinocembrin, coumaric acid, caffeic acid and caffeic acid phenethyl ester, that have already been described in these propolis with conventional HPLC. Although all propolis samples inhibited the mutans streptococci growth, it was observed a wide spectrum of action (MIC 0.90 to 8.22 µgmL-1. Given that results it becomes increasingly evident the need of standardization procedures, where we combine both the determination of botanical and the chemical characterization of the extracts. Research conducted to date, describes a promising effectiveness of propolis in the prevention of caries and other diseases of the oral cavity, making it necessary to develop studies to identify and understand the therapeutic targets or mechanisms of molecular action of the various compounds present on them.

  9. Chemical and botanical characterization of Chilean propolis and biological activity on cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus.

    Science.gov (United States)

    Barrientos, Leticia; Herrera, Christian L; Montenegro, Gloria; Ortega, Ximena; Veloz, Jorge; Alvear, Marysol; Cuevas, Alejandro; Saavedra, Nicolás; Salazar, Luis A

    2013-01-01

    Propolis is a non-toxic natural substance with multiple pharmacological properties including anti-cancer, antioxidant, fungicidal, antibacterial, antiviral, and anti-inflammatory among others. The aim of this study was to determine the chemical and botanical characterization of Chilean propolis samples and to evaluate their biological activity against the cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. Twenty propolis samples were obtained from beekeeping producers from the central and southern regions of Chile. The botanical profile was determined by palynological analysis. Total phenolic contents were determined using colorimetric assays. Reverse phase HPLC and HPLC-MS were used to determine the chemical composition. The minimum inhibitory concentration (MIC) was determined on S. mutans and S. sobrinus. All propolis samples were dominated by structures from native plant species. The characterization by HPLC/MS, evidenced the presence of quercetin, myricetin, kaempferol, rutine, pinocembrin, coumaric acid, caffeic acid and caffeic acid phenethyl ester, that have already been described in these propolis with conventional HPLC. Although all propolis samples inhibited the mutans streptococci growth, it was observed a wide spectrum of action (MIC 0.90 to 8.22 μg mL(-1)). Given that results it becomes increasingly evident the need of standardization procedures, where we combine both the determination of botanical and the chemical characterization of the extracts. Research conducted to date, describes a promising effectiveness of propolis in the prevention of caries and other diseases of the oral cavity, making it necessary to develop studies to identify and understand the therapeutic targets or mechanisms of molecular action of the various compounds present on them.

  10. Inhibiting effects of Streptococcus salivarius on competence-stimulating peptide-dependent biofilm formation by Streptococcus mutans.

    Science.gov (United States)

    Tamura, S; Yonezawa, H; Motegi, M; Nakao, R; Yoneda, S; Watanabe, H; Yamazaki, T; Senpuku, H

    2009-04-01

    The effects of Streptococcus salivarius on the competence-stimulating peptide (CSP)-dependent biofilm formation by Streptococcus mutans were investigated. Biofilms were grown on 96-well microtiter plates coated with salivary components in tryptic soy broth without dextrose supplemented with 0.25% sucrose. Biofilm formations were stained using safranin and quantification of stained biofilms was performed by measuring absorbance at 492 nm. S. mutans formed substantial biofilms, whereas biofilms of S. salivarius were formed poorly in the medium conditions used. Furthermore, in combination cultures, S. salivarius strongly inhibited biofilm formation when cultured with S. mutans. This inhibition occurred in the early phase of biofilm formation and was dependent on inactivation of the CSP of S. mutans, which is associated with competence, biofilm formation, and antimicrobial activity of the bacterium, and is induced by expression of the comC gene. Comparisons between the S. mutans clinical strains FSC-3 and FSC-3DeltaglrA in separate dual-species cultures with S. salivarius indicated that the presence of the bacitracin transport ATP-binding protein gene glrA caused susceptibility to inhibition of S. mutans biofilm formation by S. salivarius, and was also associated with the regulation of CSP production by com gene-dependent quorum sensing systems. It is considered that regulation of CSP by glrA in S. mutans and CSP inactivation by S. salivarius are important functions for cell-to-cell communication between biofilm bacteria and oral streptococci such as S. salivarius. Our results provide useful information for understanding the ecosystem of oral streptococcal biofilms, as well as the competition between and coexistence of multiple species in the oral cavity.

  11. The antimicrobial sensitivity of Streptococcus mutans and Streptococcus sangius to colloidal solutions of different nanoparticles applied as mouthwashes

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    Farzaneh Ahrari

    2015-01-01

    Full Text Available Background: Metal nanoparticles have been recently applied in dentistry because of their antibacterial properties. This study aimed to evaluate antibacterial effects of colloidal solutions containing zinc oxide (ZnO, copper oxide (CuO, titanium dioxide (TiO 2 and silver (Ag nanoparticles on Streptococcus mutans and Streptococcus sangius and compare the results with those of chlorhexidine and sodium fluoride mouthrinses. Materials and Methods: After adding nanoparticles to a water-based solution, six groups were prepared. Groups I to IV included colloidal solutions containing nanoZnO, nanoCuO, nanoTiO 2 and nanoAg, respectively. Groups V and VI consisted of 2.0% sodium fluoride and 0.2% chlorhexidine mouthwashes, respectively as controls. We used serial dilution method to find minimum inhibitory concentrations (MICs and with subcultures obtained minimum bactericidal concentrations (MBCs of the solutions against S. mutans and S. sangius. The data were analyzed by analysis of variance and Duncan test and P < 0.05 was considered as significant. Results: The sodium fluoride mouthrinse did not show any antibacterial effect. The nanoTiO 2 -containing solution had the lowest MIC against both microorganisms and also displayed the lowest MBC against S. mutans (P < 0.05. The colloidal solutions containing nanoTiO 2 and nanoZnO showed the lowest MBC against S. sangius (P < 0.05. On the other hand, chlorhexidine showed the highest MIC and MBC against both streptococci (P < 0.05. Conclusion: The nanoTiO 2 -containing mouthwash proved to be an effective antimicrobial agent and thus it can be considered as an alternative to chlorhexidine or sodium fluoride mouthrinses in the oral cavity provided the lack of cytotoxic and genotoxic effects on biologic tissues.

  12. Acid Stress Response Mechanisms of Group B Streptococci

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    Sarah Shabayek

    2017-09-01

    Full Text Available Group B streptococcus (GBS is a leading cause of neonatal mortality and morbidity in the United States and Europe. It is part of the vaginal microbiota in up to 30% of pregnant women and can be passed on to the newborn through perinatal transmission. GBS has the ability to survive in multiple different host niches. The pathophysiology of this bacterium reveals an outstanding ability to withstand varying pH fluctuations of the surrounding environments inside the human host. GBS host pathogen interations include colonization of the acidic vaginal mucosa, invasion of the neutral human blood or amniotic fluid, breaching of the blood brain barrier as well as survival within the acidic phagolysosomal compartment of macrophages. However, investigations on GBS responses to acid stress are limited. Technologies, such as whole genome sequencing, genome-wide transcription and proteome mapping facilitate large scale identification of genes and proteins. Mechanisms enabling GBS to cope with acid stress have mainly been studied through these techniques and are summarized in the current review

  13. Genetic polymorphism of Streptococcus mutans in Brazilian family members Polimorfismo genético de Streptococcus mutans em membros de famílias brasileiras

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    Denise Madalena Palomari Spolidorio

    2003-07-01

    Full Text Available The aim of this study was to determine whether random amplified polymorphic DNA (AP-PCR analysis is able to differentiate genetically different clones of mutans streptococci, in 22 Brazilian family members. Stimulated saliva samples were collected from fathers, mothers and infants. For 5-18 months babies with erupting primary dentition, plaque samples were collected using sterile tooth pick tips. From these samples, mutans streptococci were isolated on SB-20 agar plates. After growth, representative colonies were identified by biochemical methods on the basis of carbohydrate fermentation. Streptococcus mutans isolates were obtained from all family members and AP-PCR typed separately with a random primer (OPA-13. Bacterial cell lysates were used as template in PCR reactions and the amplified DNA fragments obtained were compared by agarose gel electrophoresis. Results demonstrated that the father shared the baby's genotype in three families and the mother shared the baby's genotype in 12 families seven babies harbored Streptococcus mutans strains similar to those of their siblings. The technique was able to demonstrate the genetic Streptococcus mutans in Brazilian family members.O objetivo deste estudo foi determinar, através da técnica de reação em cadeia da polimerase com primers arbitrários (AP-PCR a capacidade de diferenciar clones geneticamente distintos de Streptococcus mutans e estabelecer o grau de similaridade intrafamilial para os isolados. Para o presente estudo, foram selecionadas 22 famílias brasileiras. Amostras de saliva foram coletadas de todos os membros das famílias. Das crianças com idade entre 5-18 meses obteve-se amostras de placa dental. Após o isolamento das colônias com características morfológicas, realizou-se a identificação bioquímica com base na fermentação de carboidratos. O polimorfismo genético de Streptococcus mutans foi pesquisado através da técnica de AP-PCR utilizando-se o primer OPA-13. Os

  14. Antibiotic Susceptibilities and Serotyping of Clinical Streptococcus Agalactiae Isolates

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    Altay Atalay

    2011-11-01

    Full Text Available Objective: Streptococcus agalactiae (Group B streptococci, GBS are frequently responsible for sepsis and meningitis seen in the early weeks of life. GBS may cause perinatal infection and premature birth in pregnant women. The aim of this study was to serotype GBS strains isolated from clinical samples and evaluate their serotype distribution according to their susceptibilities to antibiotics and isolation sites. Material and Methods: One hundred thirty one S. agalactiae strains isolated from the clinical samples were included in the study. Of the strains, 99 were isolated from urine, 20 from soft tissue, 10 from blood and 2 from vaginal swab. Penicillin G and ceftriaxone susceptibilities of GBS were determined by the agar dilution method. Susceptibilities to erythromycin, clindamycin, vancomycin and tetracycline were determined by the Kirby-Bauer method according to CLSI criteria. Serotyping was performed using the latex aglutination method using specific antisera (Ia, Ib, II-VIII. Results: While in 131 GBS strains, serotypes VII and VIII were not detected, the most frequently isolated serotypes were types Ia (36%, III (30.5% and II (13% respectively. Serotype Ia was the most frequently seen serotype in all samples. All GBS isolates were susceptible to penicilin G, ceftriaxone and vancomycin. Among the strains, tetracycline, erythromycin and clindamycin resistance rates were determined as 90%, 14.5%, and 13% respectively. Conclusion: Penicillin is still the first choice of treatment for the infections with all serotypes of S. agalactiae in Turkey.

  15. Different bacteriocin activities of Streptococcus mutans reflect distinct phylogenetic lineages

    DEFF Research Database (Denmark)

    Balakrishnan, M; Simmonds, RS; Kilian, Mogens

    2002-01-01

    Bacteriocins produced by mutans streptococci are known as mutacins. In this study 16 broadly active mutacin-producing Streptococcus mutans strains from New Zealand, North America and Europe were classified into four groups (A-D) on the basis of differences in their activity in deferred antagonism...... described by Caufield and co-workers. One of the New Zealand isolates of group A (S. mutans strain N) appeared to produce inhibitory activity similar to that of the group I prototype strain UA140. Four other New Zealand isolates of group B (S. mutans strains M19, M34, B34 and D14) had mutacin II......-like activity. The group B mutacin producers differed from the group A mutacin producers in their additional activity against Staph. aureus 46. Seven S. mutans strains (M46, B46, B57, M12, M28, B28 and 13M) were distinguished from the group A and group B mutacin producers in that they inhibited E. faecium TE1...

  16. AdcAII of Streptococcus pneumoniae Affects Pneumococcal Invasiveness.

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    Lindsey R Brown

    Full Text Available Across bacterial species, metal binding proteins can serve functions in pathogenesis in addition to regulating metal homeostasis. We have compared and contrasted the activities of zinc (Zn2+-binding lipoproteins AdcA and AdcAII in the Streptococcus pneumoniae TIGR4 background. Exposure to Zn2+-limiting conditions resulted in delayed growth in a strain lacking AdcAII (ΔAdcAII when compared to wild type bacteria or a mutant lacking AdcA (ΔAdcA. AdcAII failed to interact with the extracellular matrix protein laminin despite homology to laminin-binding proteins of related streptococci. Deletion of AdcA or AdcAII led to significantly increased invasion of A549 human lung epithelial cells and a trend toward increased invasion in vivo. Loss of AdcAII, but not AdcA, was shown to negatively impact early colonization of the nasopharynx. Our findings suggest that expression of AdcAII affects invasiveness of S. pneumoniae in response to available Zn2+ concentrations.

  17. Potential Transmission Pathways of Streptococcus gallolyticus subsp. gallolyticus.

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    Jessika Dumke

    Full Text Available Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus subsp. gallolyticus, a member of group D streptococci, is an inhabitant of the animal and human gastrointestinal tract. Furthermore, it is a facultative pathogen which causes e.g. endocarditis, septicemia and mastitis. S. gallolyticus subsp. gallolyticus may be transmitted either directly or indirectly between animals and humans. However, the transmission routes are an unsolved issue. In this study, we present systematic analyses of an S. gallolyticus subsp. gallolyticus isolate of an infective endocarditis patient in relation to isolates of his laying hen flock. Isolates from pooled droppings of laying hens, pooled dust samples and human blood culture were characterized by using multilocus sequence typing (MLST and DNA fingerprinting. MLST revealed the same allelic profile of isolates from the human blood culture and from the droppings of laying hens. In addition, these isolates showed clonal identity regarding a similar DNA fingerprinting pattern. For the first time, we received a hint that transmission of S. gallolyticus subsp. gallolyticus between poultry and humans may occur. This raises the question about the zoonotic potential of isolates from poultry and should be considered in future studies.

  18. Streptococcus pyogenes biofilms – formation, biology,and clinical relevance

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    Tomas eFiedler

    2015-02-01

    Full Text Available Streptococcus pyogenes (group A streptococci, GAS is an exclusive human bacterial pathogen. The virulence potential of this species is tremendous. Interactions with humans range from asymptomatic carriage over mild and superficial infections of skin and mucosal membranes up to systemic purulent toxic-invasive disease manifestations. Particularly the latter are a severe threat for predisposed patients and lead to significant death tolls worldwide. This places GAS among the most important Gram-positive bacterial pathogens. Many recent reviews have highlighted the GAS repertoire of virulence factors, regulators and regulatory circuits/networks that enable GAS to colonize the host and to deal with all levels of the host immune defense. This covers in vitro and in vivo studies, including animal infection studies based on mice and more relevant, macaque monkeys. It is now appreciated that GAS, like many other bacterial species, do not necessarily exclusively live in a planktonic lifestyle. GAS is capable of microcolony and biofilm formation on host cells and tissues. We are now beginning to understand that this feature significantly contributes to GAS pathogenesis. In this review we will discuss the current knowledge on GAS biofilm formation, the biofilm-phenotype associated virulence factors, regulatory aspects of biofilm formation, the clinical relevance, and finally contemporary treatment regimens and future treatment options.

  19. [A Patient with a Wedge-shaped Pulmonary Lesion Associated with Streptococcus parasanguinis].

    Science.gov (United States)

    Miyamoto, Hiroya; Gomi, Harumi; Ishioka, Haruhiko; Shirokawa, Taijiro

    2016-05-01

    An 84-year-old man was admitted to our hospital with bloody sputum. He was found to have a right lower lobe wedge-shaped nodular lesion with chest X-ray and computed tomography of the chest. Ceftriaxone and minocycline were started empirically based on a working diagnosis of community-acquired pneumonia. Streptococcus parasanguinis was isolated with sputum cultures obtained on three consecutive days and was identified based on its biochemical properties. S. parasanguinis is a member of the sanguinis group of viridans Streptococci. It is known as a causative pathogen for endocarditis. There are very few reports of S. parasanguinis associated with pulmonary infections. The present report describes the association of S. parasanguinis with a wedge-shaped nodular lesion in the lungs.

  20. Fueling the caries process: carbohydrate metabolism and gene regulation by Streptococcus mutans

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    Zachary D. Moye

    2014-09-01

    Full Text Available The nature of the oral cavity and host behaviors has mandated that the oral microbiota evolve mechanisms for coping with environmental fluctuations, especially changes in the type and availability of carbohydrates. In the case of human dental caries, the presence of excess carbohydrates is often responsible for altering the local environment to be more favorable for species associated with the initiation and progression of disease, including Streptococcus mutans. Some of the earliest endeavors to understand how cariogenic species respond to environmental perturbations were carried out using chemostat cultivation, which provides fine control over culture conditions and bacterial behaviors. The development of genome-scale methodologies has allowed for the combination of sophisticated cultivation technologies with genome-level analysis to more thoroughly probe how bacterial pathogens respond to environmental stimuli. Recent investigations in S. mutans and other closely related streptococci have begun to reveal that carbohydrate metabolism can drastically impact pathogenic potential and highlight the important influence that nutrient acquisition has on the success of pathogens; inside and outside of the oral cavity. Collectively, research into pathogenic streptococci, which have evolved in close association with the human host, has begun to unveil the essential nature of careful orchestration of carbohydrate acquisition and catabolism to allow the organisms to persist and, when conditions allow, initiate or worsen disease.

  1. Fueling the caries process: carbohydrate metabolism and gene regulation by Streptococcus mutans

    Science.gov (United States)

    Moye, Zachary D.; Zeng, Lin; Burne, Robert A.

    2014-01-01

    The nature of the oral cavity and host behaviors has mandated that the oral microbiota evolve mechanisms for coping with environmental fluctuations, especially changes in the type and availability of carbohydrates. In the case of human dental caries, the presence of excess carbohydrates is often responsible for altering the local environment to be more favorable for species associated with the initiation and progression of disease, including Streptococcus mutans. Some of the earliest endeavors to understand how cariogenic species respond to environmental perturbations were carried out using chemostat cultivation, which provides fine control over culture conditions and bacterial behaviors. The development of genome-scale methodologies has allowed for the combination of sophisticated cultivation technologies with genome-level analysis to more thoroughly probe how bacterial pathogens respond to environmental stimuli. Recent investigations in S. mutans and other closely related streptococci have begun to reveal that carbohydrate metabolism can drastically impact pathogenic potential and highlight the important influence that nutrient acquisition has on the success of pathogens; inside and outside of the oral cavity. Collectively, research into pathogenic streptococci, which have evolved in close association with the human host, has begun to unveil the essential nature of careful orchestration of carbohydrate acquisition and catabolism to allow the organisms to persist and, when conditions allow, initiate or worsen disease. PMID:25317251

  2. Survival and activity of Streptococcus faecalis and Escherichia coli in petroleum-contaminated tropical marine waters

    Energy Technology Data Exchange (ETDEWEB)

    Santo Domingo, J.W.; Fuentes, F.A.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Microbial Ecology Lab.

    1987-12-31

    The in situ survival and activity of Streptococcus faecalis and Escherichia coli were studied using membrane diffusion chambers in tropical marine waters receiving oil refinery effluents. Protein synthesis, DNA synthesis, respiration or fermentation, INT reduced per cell, and ATP per cell were used to measure physiological activity. Cell densities decreased significantly over time at both sites for both S. faecalis and E. coli; however, no significant differences in survival pattern were observed between S. faecalis and E.coli. Differences in protein synthesis between the two were only observed at a study site which was not heavily oiled. Although fecal streptococci have been suggested as a better indicator of fecal contamination than fecal coliforms in marine waters, in this study both E. coli and S. faecalis survived and remained physiologically active for extended periods of time. These results suggest that the fecal streptococci group is not a better indicator of fecal contamination in tropical marine waters than the fecal coliform group, especially when that environment is high in long-chained hydrocarbons.

  3. Binding Properties of Streptococcus gordonii SspA and SspB (Antigen I/II Family) Polypeptides Expressed on the Cell Surface of Lactococcus lactis MG1363

    OpenAIRE

    Holmes, Ann R.; Gilbert, Christophe; Wells, Jeremy M.; Jenkinson, Howard F.

    1998-01-01

    The oral bacterium Streptococcus gordonii expresses two cell wall-associated polypeptides, designated SspA (1,542 amino acid residues) and SspB (1,462 amino acid residues), that have 70% sequence identity. These polypeptides are members of the antigen I/II family of oral streptococcal adhesins and mediate the binding of streptococci to salivary glycoproteins, collagen, and other oral microorganisms such as Actinomyces naeslundii. To determine if SspA and SspB have differential binding propert...

  4. Effect of subclinical mastitis caused by ss-haemolytic streptococci on ...

    African Journals Online (AJOL)

    Mastitis is a major constraint to milk production in camels. We conducted a survey in Marsabit and Isiolo counties of Kenya to quantify losses in milk yield associated with subclinical mastitis caused by ß-haemolytic Streptococci in the one-humped camel (Camelus dromedarius). Four hundred and twenty (420) pair wise ...

  5. Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995-1998

    NARCIS (Netherlands)

    Lin, FYC; Azimi, PH; Weisman, LE; Philips, JB; Regan, J; Clark, P; Rhoads, GG; Clemens, J; Troendle, J; Pratt, E; Brenner, RA; Gill, [No Value

    Antibiotic susceptibility profiles were analyzed for 119 invasive and 227 colonizing strains of group B streptococci isolated from neonates at 6 US academic centers, All strains were susceptible to penicillin, vancomycin, chloramphenicol, and cefotaxime, The rate of resistance to erythromycin was

  6. The Effects of a Dairy Probiotic Product, Espar, on Salivary Calcium and Mutans Streptococci

    Directory of Open Access Journals (Sweden)

    Hamidreza Poureslami

    2013-08-01

    Full Text Available Background and aims. Espar is a dairy product of probiotic nature that contains useful bacteria and high calcium content. The aim of this study was to analyze effects of daily consumption of Espar on the number of salivary mutans streptococci and the level of calcium content in a population of 15 to 17 year-old female students. Materials and methods. A double-blind randomized crossover study (n = 50 of healthy female adolescents was implemented in four stage intervals. The first and third stages were ‘run-in’ and ‘wash-out’ intervals. For the second and fourth stages, two weeks long in duration, the participants consumed 100 grams of Espar or 200 grams of plain yogurt. At the end of each stage, the number of salivary mutans streptococci and the level of calcium content were documented. Results. There was a statistically significant decrease in the number of salivary mutans streptococci subsequent to Espar consumption when compared to ordinary yogurt (p < 0.01. Additionally, salivary calcium content increased significantly subsequent to the consumption of Espar and yogurt. However, Espar yielded a higher level of significant increase in salivary calcium when compared to plain yogurt (p < 0.01. Conclusion. This study found that daily consumption of Espar increased the salivary calcium level while decreasing mutans streptococci of the saliva.

  7. Group B streptococci cultured in urine during pregnancy associated with preterm delivery

    DEFF Research Database (Denmark)

    Khalil, Mohammed R; Uldbjerg, Niels; Møller, Jens K

    2018-01-01

    OBJECTIVE: To investigate an association between Group B streptococci (GBS) in urine culture during pregnancy and preterm delivery. METHODS: A population-based cohort consisted of all the pregnant women (n = 36,097) from the catchment area of Lillebaelt Hospital, Denmark, during the period Januar...

  8. Pediatric Infective Endocarditis: Has Staphylococcus aureus Overtaken Viridans Group Streptococci as the Predominant Etiological Agent?

    Directory of Open Access Journals (Sweden)

    Aisha Alshammary

    2008-01-01

    Full Text Available BACKGROUND: Viridans group streptococci (VGS have traditionally been the most common etiological agents of infective endocarditis (IE. Advances in cardiovascular surgery and the increasing use of long-term central venous catheters may have altered the epidemiology of pediatric IE.

  9. The Mobile Insulin Titration Intervention (MITI) for Insulin Adjustment in an Urban, Low-Income Population: Randomized Controlled Trial.

    Science.gov (United States)

    Levy, Natalie; Moynihan, Victoria; Nilo, Annielyn; Singer, Karyn; Bernik, Lidia S; Etiebet, Mary-Ann; Fang, Yixin; Cho, James; Natarajan, Sundar

    2015-07-17

    Diabetes patients are usually started on a low dose of insulin and their dose is adjusted or "titrated" according to their blood glucose levels. Insulin titration administered through face-to-face visits with a clinician can be time consuming and logistically burdensome for patients, especially those of low socioeconomic status (SES). Given the wide use of mobile phones among this population, there is the potential to use short message service (SMS) text messaging and phone calls to perform insulin titration remotely. The goals of this pilot study were to (1) evaluate if our Mobile Insulin Titration Intervention (MITI) intervention using text messaging and phone calls was effective in helping patients reach their optimal insulin glargine dose within 12 weeks, (2) assess the feasibility of the intervention within our clinic setting and patient population, (3) collect data on the cost savings associated with the intervention, and (4) measure patient satisfaction with the intervention. This was a pilot study evaluating an intervention for patients requiring insulin glargine titration in the outpatient medical clinic of Bellevue Hospital Center in New York City. Patients in the intervention arm received weekday SMS text messages from a health management platform requesting their fasting blood glucose values. The clinic's diabetes nurse educator monitored the texted responses on the platform website each weekday for alarm values. Once a week, the nurse reviewed the glucose values, consulted the MITI titration algorithm, and called patients to adjust their insulin dose. Patients in the usual care arm continued to receive their standard clinic care for insulin titration. The primary outcome was whether a patient reached his/her optimal insulin glargine dose within 12 weeks. A total of 61 patients consented and were randomized into the study. A significantly greater proportion of patients in the intervention arm reached their optimal insulin glargine dose than patients in

  10. Association between group A beta-haemolytic streptococci and vulvovaginitis in adult women: a case-control study.

    Science.gov (United States)

    Bruins, M J; Damoiseaux, R A M J; Ruijs, G J H M

    2009-08-01

    Guidelines for the management of vaginal discharge mention Candida albicans, Trichomonas vaginalis, bacterial vaginosis, Chlamydia trachomatis and Neisseria gonorrhoeae as causes and do not recommend full microbiological culture. The role of non-group B beta-haemolytic streptococci in vaginal cultures is unclear, except for group A streptococci that are known to cause vulvovaginitis in children. In a case-control study, we investigated the association between non-group B beta-haemolytic streptococci and vulvovaginitis in adult women. Cases were women with recurrent vaginal discharge from whom a sample was cultured. Controls were asymptomatic women who consented to submitting a vaginal swab. Group A streptococci were isolated from 49 (4.9%) of 1,010 cases and not from the 206 controls (P < 0.01). Isolation rates of group C, F and G streptococci were low and did not differ statistically between cases and controls. Group A beta-haemolytic streptococci are associated with vaginal discharge in adult women. The other non-group B streptococci require more study. For the adequate management of vaginal discharge, culturing is necessary if initial treatment fails. Guidelines should be amended according to these results.

  11. Correlation of Streptococcus mutans and Streptococcus sanguinis colonization and ex vivo hydrogen peroxide production in carious lesion-free and high caries adults.

    Science.gov (United States)

    Giacaman, Rodrigo A; Torres, Sebastián; Gómez, Yenifer; Muñoz-Sandoval, Cecilia; Kreth, Jens

    2015-01-01

    This study was conducted to estimate oral colonization by Streptococcus mutans and Streptococcus sanguinis in adults with high and without any caries experience. Furthermore, differences in the amount of hydrogen peroxide (H2O2) produced by S. sanguinis isolated from both groups were assessed. Forty adults were divided into: (i) carious lesion-free, without any carious lesion, assessed by the International Caries Detection and Assessment System (ICDAS), or restoration, (CF) and (ii) high caries experience (HC). Saliva samples were collected and seeded on respective agar-plates for enumeration of total streptococci, S. mutans and S. sanguinis (CFU/mL) and compared between groups. Additionally, S. sanguinis colonies obtained from both groups were inoculated on Prussian blue agar for H2O2 detection. Production of H2O2 was quantified and compared between the two groups. S. sanguinis counts were significantly higher in CF than HC individuals (pmutans showed significantly higher levels in HC than CF subjects (pmutans in saliva of adults without caries experience. In those people, S. sanguinis produces more H2O2ex vivo. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Beyond Streptococcus mutans: Dental Caries Onset Linked to Multiple Species by 16S rRNA Community Analysis

    Science.gov (United States)

    Gross, Erin L.; Beall, Clifford J.; Kutsch, Stacey R.; Firestone, Noah D.; Leys, Eugene J.; Griffen, Ann L.

    2012-01-01

    Dental caries in very young children may be severe, result in serious infection, and require general anesthesia for treatment. Dental caries results from a shift within the biofilm community specific to the tooth surface, and acidogenic species are responsible for caries. Streptococcus mutans, the most common acid producer in caries, is not always present and occurs as part of a complex microbial community. Understanding the degree to which multiple acidogenic species provide functional redundancy and resilience to caries-associated communities will be important for developing biologic interventions. In addition, microbial community interactions in health and caries pathogenesis are not well understood. The purpose of this study was to investigate bacterial community profiles associated with the onset of caries in the primary dentition. In a combination cross-sectional and longitudinal design, bacterial community profiles at progressive stages of caries and over time were examined and compared to those of health. 16S rRNA gene sequencing was used for bacterial community analysis. Streptococcus mutans was the dominant species in many, but not all, subjects with caries. Elevated levels of S. salivarius, S. sobrinus, and S. parasanguinis were also associated with caries, especially in subjects with no or low levels of S. mutans, suggesting these species are alternative pathogens, and that multiple species may need to be targeted for interventions. Veillonella, which metabolizes lactate, was associated with caries and was highly correlated with total acid producing species. Among children without previous history of caries, Veillonella, but not S. mutans or other acid-producing species, predicted future caries. Bacterial community diversity was reduced in caries as compared to health, as many species appeared to occur at lower levels or be lost as caries advanced, including the Streptococcus mitis group, Neisseria, and Streptococcus sanguinis. This may have

  13. Role of the Group B antigen of Streptococcus agalactiae: a peptidoglycan-anchored polysaccharide involved in cell wall biogenesis.

    Directory of Open Access Journals (Sweden)

    Élise Caliot

    Full Text Available Streptococcus agalactiae (Group B streptococcus, GBS is a leading cause of infections in neonates and an emerging pathogen in adults. The Lancefield Group B carbohydrate (GBC is a peptidoglycan-anchored antigen that defines this species as a Group B Streptococcus. Despite earlier immunological and biochemical characterizations, the function of this abundant glycopolymer has never been addressed experimentally. Here, we inactivated the gene gbcO encoding a putative UDP-N-acetylglucosamine-1-phosphate:lipid phosphate transferase thought to catalyze the first step of GBC synthesis. Indeed, the gbcO mutant was unable to synthesize the GBC polymer, and displayed an important growth defect in vitro. Electron microscopy study of the GBC-depleted strain of S. agalactiae revealed a series of growth-related abnormalities: random placement of septa, defective cell division and separation processes, and aberrant cell morphology. Furthermore, vancomycin labeling and peptidoglycan structure analysis demonstrated that, in the absence of GBC, cells failed to initiate normal PG synthesis and cannot complete polymerization of the murein sacculus. Finally, the subcellular localization of the PG hydrolase PcsB, which has a critical role in cell division of streptococci, was altered in the gbcO mutant. Collectively, these findings show that GBC is an essential component of the cell wall of S. agalactiae whose function is reminiscent of that of conventional wall teichoic acids found in Staphylococcus aureus or Bacillus subtilis. Furthermore, our findings raise the possibility that GBC-like molecules play a major role in the growth of most if not all beta-hemolytic streptococci.

  14. Acidogenic properties of Streptococcus mutans

    International Nuclear Information System (INIS)

    Stoesser, L.; Kneist, S.; Tumovec, M.; Katzmann, M.

    1988-01-01

    The growth kinetic parameters of S. mutans OMZ 176 culture as well as the 32 PO 4 uptake, as a measure of living cell mass, and the acid production rate by germ suspensions in a pH-stat technique were estimated. Subsequently, the acidogenicity of 20 S. mutans strains, other oral streptococci and dental plaque was measured and compared taking into consideration the growth kinetic dependence of studied activities. The strains OMZ 176 and OMZ 65 exhibited the most acidogenic properties whereas FA 1 produced 3.6 times less acid. (author)

  15. A Highly Arginolytic Streptococcus Species That Potently Antagonizes Streptococcus mutans.

    Science.gov (United States)

    Huang, Xuelian; Palmer, Sara R; Ahn, Sang-Joon; Richards, Vincent P; Williams, Matthew L; Nascimento, Marcelle M; Burne, Robert A

    2016-01-29

    The ability of certain oral biofilm bacteria to moderate pH through arginine metabolism by the arginine deiminase system (ADS) is a deterrent to the development of dental caries. Here, we characterize a novel Streptococcus strain, designated strain A12, isolated from supragingival dental plaque of a caries-free individual. A12 not only expressed the ADS pathway at high levels under a variety of conditions but also effectively inhibited growth and two intercellular signaling pathways of the dental caries pathogen Streptococcus mutans. A12 produced copious amounts of H2O2 via the pyruvate oxidase enzyme that were sufficient to arrest the growth of S. mutans. A12 also produced a protease similar to challisin (Sgc) of Streptococcus gordonii that was able to block the competence-stimulating peptide (CSP)-ComDE signaling system, which is essential for bacteriocin production by S. mutans. Wild-type A12, but not an sgc mutant derivative, could protect the sensitive indicator strain Streptococcus sanguinis SK150 from killing by the bacteriocins of S. mutans. A12, but not S. gordonii, could also block the XIP (comX-inducing peptide) signaling pathway, which is the proximal regulator of genetic competence in S. mutans, but Sgc was not required for this activity. The complete genome sequence of A12 was determined, and phylogenomic analyses compared A12 to streptococcal reference genomes. A12 was most similar to Streptococcus australis and Streptococcus parasanguinis but sufficiently different that it may represent a new species. A12-like organisms may play crucial roles in the promotion of stable, health-associated oral biofilm communities by moderating plaque pH and interfering with the growth and virulence of caries pathogens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  16. Necrotizing soft tissue infections caused by Streptococcus pyogenes and Streptococcus dysgalactiae subsp. equisimilis of groups C and G in western Norway.

    Science.gov (United States)

    Bruun, T; Kittang, B R; de Hoog, B J; Aardal, S; Flaatten, H K; Langeland, N; Mylvaganam, H; Vindenes, H A; Skrede, S

    2013-12-01

    Streptococcus pyogenes (group A streptococcus, GAS) is a major cause of necrotizing soft tissue infection (NSTI). On rare occasions, other β-haemolytic streptococci may also cause NSTI, but the significance and nature of these infections has not been thoroughly investigated. In this study, clinical and molecular characteristics of NSTI caused by GAS and β-haemolytic Streptococcus dysgalactiae subsp. equisimilis of groups C and G (GCS/GGS) in western Norway during 2000-09 are presented. Clinical data were included retrospectively. The bacterial isolates were subsequently emm typed and screened for the presence of genes encoding streptococcal superantigens. Seventy cases were identified, corresponding to a mean annual incidence rate of 1.4 per 100 000. Sixty-one of the cases were associated with GAS, whereas GCS/GGS accounted for the remaining nine cases. The in-hospital case fatality rates of GAS and GCS/GGS disease were 11% and 33%, respectively. The GCS/GGS patients were older, had comorbidities more often and had anatomically more superficial disease than the GAS patients. High age and toxic shock syndrome were associated with mortality. The Laboratory Risk Indicator for Necrotizing Fasciitis laboratory score showed high values (≥6) in only 31 of 67 cases. Among the available 42 GAS isolates, the most predominant emm types were emm1, emm3 and emm4. The virulence gene profiles were strongly correlated to emm type. The number of superantigen genes was low in the four available GCS/GGS isolates. Our findings indicate a high frequency of streptococcal necrotizing fasciitis in our community. GCS/GGS infections contribute to the disease burden, but differ from GAS cases in frequency and predisposing factors. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  17. IgA anti-Streptococcus mutans em crianças com e sem cárie dentária Anti-Streptococcus mutans IgA in children with and without dental caries

    Directory of Open Access Journals (Sweden)

    Suzete Cristina YAZAKI

    1999-07-01

    Full Text Available A cárie dentária é uma doença infecciosa crônica que necessita pelo menos quatro componentes para desenvolver-se: hospedeiro suscetível, microbiota patogênica, dieta rica em sacarose e tempo. Este trabalho estuda as correlações existentes entre estreptococos salivares do grupo mutans, placa bacteriana e anticorpos IgA anti-Streptococcus mutans em crianças com e sem experiência de cárie. Para tanto, utilizou-se o meio Mitis Salivarius (DIFCO para determinar o número de Unidades Formadoras de Colônias (UFC/ml, o Índice de Higiene Oral Simplificado (IHOS para mensurar a quantidade de placa bacteriana e a técnica ELISA para detectar anticorpos anti-S. mutans. Os resultados obtidos mostraram que não existe uma correlação entre os níveis salivares de estreptococos (UFC/ml e IgA anti-S. mutans na população estudada. No grupo com cárie, uma correlação positiva, estatisticamente significante, foi observada entre o Índice de placa e IgA específica.Dental caries is a chronic infectious disease that needs at least four components to develop. As a susceptible host, a pathogenic microbiota, a high-sucrose diet and time. This work assess the relationships between Streptococcus mutans and dental plaque; Streptococcus mutans and IgA antibodies in children with and without caries experience. In order to achieve this goal we have used Mitis Salivarius bacitracin agar (DIFCO to determine the colony forming units (CFU/mL, the simplified oral hygiene index (SOHI for measuring bacterial plaque and ELISA for antibody detection. The results obtained have not shown any correlations between colony forming units of S. mutans and IgA antibodies. A significant correlation was found between bacterial plaque index and specific IgA in children with carious lesions.

  18. Antimicrobial and anti-virulence activity of capsaicin against erythromycin-resistant, cell-invasive Group A streptococci

    Directory of Open Access Journals (Sweden)

    Emanuela eMarini

    2015-11-01

    Full Text Available Capsaicin (8-methyl-N-vanillyl-6-nonenamide is the active component of Capsicum plants (chilli peppers, which are grown as food and for medicinal purposes since ancient times, and is responsible for the pungency of their fruit. Besides its multiple pharmacological and physiological properties (pain relief, cancer prevention, and beneficial cardiovascular, and gastrointestinal effects capsaicin has recently attracted considerable attention because of its antimicrobial and anti-virulence activity. This is the first study of its in vitro antibacterial and anti-virulence activity against Streptococcus pyogenes [Group A streptococci (GAS], a major human pathogen. The test strains were previously characterized, erythromycin-susceptible (n=5 and erythromycin-resistant (n=27, cell-invasive pharyngeal isolates. The MICs of capsaicin were 64-128 μg/mL (the most common MIC was 128 µg/mL. The action of capsaicin was bactericidal, as suggested by MBC values that were equal or close to the MICs, and by early detection of dead cells in the live/dead assay. No capsaicin-resistant mutants were obtained in single-step resistance selection studies. Interestingly, growth in presence of sublethal capsaicin concentrations induced an increase in biofilm production (p ≤ 0.05 and in the number of bacteria adhering to A549 monolayers, and a reduction in cell-invasiveness and haemolytic activity (both p ≤ 0.05. Cell invasiveness fell so dramatically that a highly invasive strain became non-invasive. The dose-response relationship, characterized by opposite effects of low and high capsaicin doses, suggests a hormetic response. The present study documents that capsaicin has promising bactericidal activity against erythromycin-resistant, cell-invasive pharyngeal GAS isolates. The fact that sublethal concentrations inhibited cell invasion and reduced haemolytic activity, two important virulence traits of GAS, is also interesting, considering that cell

  19. A novel computational method identifies intra- and inter-species recombination events in Staphylococcus aureus and Streptococcus pneumoniae.

    Directory of Open Access Journals (Sweden)

    Lisa Sanguinetti

    Full Text Available Advances in high-throughput DNA sequencing technologies have determined an explosion in the number of sequenced bacterial genomes. Comparative sequence analysis frequently reveals evidences of homologous recombination occurring with different mechanisms and rates in different species, but the large-scale use of computational methods to identify recombination events is hampered by their high computational costs. Here, we propose a new method to identify recombination events in large datasets of whole genome sequences. Using a filtering procedure of the gene conservation profiles of a test genome against a panel of strains, this algorithm identifies sets of contiguous genes acquired by homologous recombination. The locations of the recombination breakpoints are determined using a statistical test that is able to account for the differences in the natural rate of evolution between different genes. The algorithm was tested on a dataset of 75 genomes of Staphylococcus aureus and 50 genomes comprising different streptococcal species, and was able to detect intra-species recombination events in S. aureus and in Streptococcus pneumoniae. Furthermore, we found evidences of an inter-species exchange of genetic material between S. pneumoniae and Streptococcus mitis, a closely related commensal species that colonizes the same ecological niche. The method has been implemented in an R package, Reco, which is freely available from supplementary material, and provides a rapid screening tool to investigate recombination on a genome-wide scale from sequence data.

  20. Genomic evidence for the evolution of Streptococcus equi: host restriction, increased virulence, and genetic exchange with human pathogens.

    Directory of Open Access Journals (Sweden)

    Matthew T G Holden

    2009-03-01

    Full Text Available The continued evolution of bacterial pathogens has major implications for both human and animal disease, but the exchange of genetic material between host-restricted pathogens is rarely considered. Streptococcus equi subspecies equi (S. equi is a host-restricted pathogen of horses that has evolved from the zoonotic pathogen Streptococcus equi subspecies zooepidemicus (S. zooepidemicus. These pathogens share approximately 80% genome sequence identity with the important human pathogen Streptococcus pyogenes. We sequenced and compared the genomes of S. equi 4047 and S. zooepidemicus H70 and screened S. equi and S. zooepidemicus strains from around the world to uncover evidence of the genetic events that have shaped the evolution of the S. equi genome and led to its emergence as a host-restricted pathogen. Our analysis provides evidence of functional loss due to mutation and deletion, coupled with pathogenic specialization through the acquisition of bacteriophage encoding a phospholipase A(2 toxin, and four superantigens, and an integrative conjugative element carrying a novel iron acquisition system with similarity to the high pathogenicity island of Yersinia pestis. We also highlight that S. equi, S. zooepidemicus, and S. pyogenes share a common phage pool that enhances cross-species pathogen evolution. We conclude that the complex interplay of functional loss, pathogenic specialization, and genetic exchange between S. equi, S. zooepidemicus, and S. pyogenes continues to influence the evolution of these important streptococci.

  1. Comparing the cariogenic species Streptococcus sobrinus and S. mutans on whole genome level

    Directory of Open Access Journals (Sweden)

    Georg Conrads

    2014-12-01

    Full Text Available Background: Two closely related species of mutans streptococci, namely Streptococcus mutans and Streptococcus sobrinus, are associated with dental caries in humans. Their acidogenic and aciduric capacity is directly associated with the cariogenic potential of these bacteria. To survive acidic and temporarily harsh conditions in the human oral cavity with hundreds of other microbial co-colonizers as competitors, both species have developed numerous mechanisms for adaptation. Objectives: The recently published novel genome information for both species is used to elucidate genetic similarities but especially differences and to discuss the impact on cariogenicity of the corresponding phenotypic properties including adhesion, carbohydrate uptake and fermentation, acid tolerance, signaling by two component systems, competence, and oxidative stress resistance. Conclusions: S. sobrinus can down-regulate the SpaA-mediated adherence to the pellicle. It has a smaller number of two-component signaling systems and bacteriocin-related genes than S. mutans, but all or even more immunity proteins. It lacks the central competence genes comC, comS, and comR. There are more genes coding for glucosyltransferases and a novel energy production pathway formed by lactate oxidase, which is not found in S. mutans. Both species show considerable differences in the regulation of fructan catabolism. However, both S. mutans and S. sobrinus share most of these traits and should therefore be considered as equally virulent with regard to dental caries.

  2. The Regulatory Small RNA MarS Supports Virulence of Streptococcus pyogenes.

    Science.gov (United States)

    Pappesch, Roberto; Warnke, Philipp; Mikkat, Stefan; Normann, Jana; Wisniewska-Kucper, Aleksandra; Huschka, Franziska; Wittmann, Maja; Khani, Afsaneh; Schwengers, Oliver; Oehmcke-Hecht, Sonja; Hain, Torsten; Kreikemeyer, Bernd; Patenge, Nadja

    2017-09-25

    Small regulatory RNAs (sRNAs) play a role in the control of bacterial virulence gene expression. In this study, we investigated an sRNA that was identified in Streptococcus pyogenes (group A Streptococcus, GAS) but is conserved throughout various streptococci. In a deletion strain, expression of mga, the gene encoding the multiple virulence gene regulator, was reduced. Accordingly, transcript and proteome analyses revealed decreased expression of several Mga-activated genes. Therefore, and because the sRNA was shown to interact with the 5' UTR of the mga transcript in a gel-shift assay, we designated it MarS for m ga-activating regulatory sRNA. Down-regulation of important virulence factors, including the antiphagocytic M-protein, led to increased susceptibility of the deletion strain to phagocytosis and reduced adherence to human keratinocytes. In a mouse infection model, the marS deletion mutant showed reduced dissemination to the liver, kidney, and spleen. Additionally, deletion of marS led to increased tolerance towards oxidative stress. Our in vitro and in vivo results indicate a modulating effect of MarS on virulence gene expression and on the pathogenic potential of GAS.

  3. Influence of preventive dental treatment on mutans streptococci counts in patients undergoing head and neck radiotherapy

    Directory of Open Access Journals (Sweden)

    Lívia Buzati Meca

    2009-01-01

    Full Text Available The aim of this study was to evaluate the influence of chlorhexidine gluconate, sodium fluoride and sodium iodine on mutans streptococci counts in saliva of irradiated patients. MATERIAL AND METHODS: Forty-five patients were separated into three experimental groups and received chlorhexidine (0.12%, sodium fluoride (0.5% or sodium iodine (2%, which were used daily during radiotherapy and for 6 months after the conclusion of the treatment. In addition, a fourth group, composed by 15 additional oncologic patients, who did not receive the mouthwash or initial dental treatment, constituted the control group. Clinical evaluations were performed in the first visit to dental clinic, after initial dental treatment, immediately before radiotherapy, after radiotherapy and 30, 60, 90 days and 6 months after the conclusion of radiotherapy. After clinical examinations, samples of saliva were inoculated on SB20 selective agar and incubated under anaerobiosis, at 37ºC for 48 h. Total mutans streptococci counts were also evaluated by using real-time PCR, through TaqMan system, with specific primers and probes for S. mutans and S. sobrinus. RESULTS: All preventive protocols were able to reduce significantly mutans streptococci counts, but chlorhexidine gluconate was the most effective, and induced a significant amelioration of radiotherapy side effects, such as mucositis and candidosis. CONCLUSION: These results highlights the importance of the initial dental treatment for patients who will be subjected to radiotherapy for head and neck cancer treatment.

  4. Characterization of binding of human alpha 2-macroglobulin to group G streptococci

    International Nuclear Information System (INIS)

    Chhatwal, G.S.; Mueller, H.P.; Blobel, H.

    1983-01-01

    An interaction was observed between human alpha 2-macroglobulin (alpha 2M) and streptococci belonging to group A, C, and G. Of 27 group C and 19 group G streptococcal cultures, 13 and 14, respectively, bound 125 I-labeled alpha 2M. Some group A streptococci also interacted with alpha 2M. A number of other bacterial species tested did not react with alpha 2M. The binding of 125 I-labeled alpha 2M to group G streptococci was time dependent, saturable, and could be inhibited by unlabeled alpha 2M. Inhibition experiments indicated that the streptococcal binding site for alpha 2M differed from the receptors for immunoglobulin G, fibrinogen, aggregated beta 2-microglobulin, albumin, and fibronectin. The alpha 2M binding activity was remarkably sensitive to trypsin and heat treatment indicating its protein nature. Kinetic analysis indicated a homogenous population of binding sites. The number of binding sites per bacterial cell was estimated to be approximately 20,000

  5. Recombination-deficient Streptococcus sanguis

    International Nuclear Information System (INIS)

    Daneo-Moore, L.; Volpe, A.

    1985-01-01

    A UV-sensitive derivative was obtained from Streptococcus sanguis Challis. The organism could be transformed with a number of small streptococcal plasmids at frequencies equal to, or 1 logarithm below, the transformation frequencies for the parent organism. However, transformation with chromosomal DNA was greatly impaired in the UV-sensitive derivative

  6. Amino Sugars Enhance the Competitiveness of Beneficial Commensals with Streptococcus mutans through Multiple Mechanisms.

    Science.gov (United States)

    Zeng, Lin; Farivar, Tanaz; Burne, Robert A

    2016-06-15

    Biochemical and genetic aspects of the metabolism of the amino sugars N-acetylglucosamine (GlcNAc) and glucosamine (GlcN) by commensal oral streptococci and the effects of these sugars on interspecies competition with the dental caries pathogen Streptococcus mutans were explored. Multiple S. mutans wild-type isolates displayed long lag phases when transferred from glucose-containing medium to medium with GlcNAc as the primary carbohydrate source, but commensal streptococci did not. Competition in liquid coculture or dual-species biofilms between S. mutans and Streptococcus gordonii showed that S. gordonii was particularly dominant when the primary carbohydrate was GlcN or GlcNAc. Transcriptional and enzymatic assays showed that the catabolic pathway for GlcNAc was less highly induced in S. mutans than in S. gordonii Exposure to H2O2, which is produced by S. gordonii and antagonizes the growth of S. mutans, led to reduced mRNA levels of nagA and nagB in S. mutans When the gene for the transcriptional regulatory NagR was deleted in S. gordonii, the strain produced constitutively high levels of nagA (GlcNAc-6-P deacetylase), nagB (GlcN-6-P deaminase), and glmS (GlcN-6-P synthase) mRNA. Similar to NagR of S. mutans (NagRSm), the S. gordonii NagR protein (NagRSg) could bind to consensus binding sites (dre) in the nagA, nagB, and glmS promoter regions of S. gordonii Notably, NagRSg binding was inhibited by GlcN-6-P, but G-6-P had no effect, unlike for NagRSm This study expands the understanding of amino sugar metabolism and NagR-dependent gene regulation in streptococci and highlights the potential for therapeutic applications of amino sugars to prevent dental caries. Amino sugars are abundant in the biosphere, so the relative efficiency of particular bacteria in a given microbiota to metabolize these sources of carbon and nitrogen might have a profound impact on the ecology of the community. Our investigation reveals that several oral commensal bacteria have a much

  7. Virulence of Group A Streptococci Is Enhanced by Human Complement Inhibitors

    DEFF Research Database (Denmark)

    Ermert, David; Shaughnessy, Jutamas; Joeris, Thorsten

    2015-01-01

    Streptococcus pyogenes, also known as Group A Streptococcus (GAS), is an important human bacterial pathogen that can cause invasive infections. Once it colonizes its exclusively human host, GAS needs to surmount numerous innate immune defense mechanisms, including opsonization by complement and c...... in studies of GAS pathogenesis and for developing vaccines and therapeutics that rely on human complement activation for efficacy.......Streptococcus pyogenes, also known as Group A Streptococcus (GAS), is an important human bacterial pathogen that can cause invasive infections. Once it colonizes its exclusively human host, GAS needs to surmount numerous innate immune defense mechanisms, including opsonization by complement...... and consequent phagocytosis. Several strains of GAS bind to human-specific complement inhibitors, C4b-binding protein (C4BP) and/or Factor H (FH), to curtail complement C3 (a critical opsonin) deposition. This results in diminished activation of phagocytes and clearance of GAS that may lead to the host being...

  8. Identification of PblB mediating galactose-specific adhesion in a successful Streptococcus pneumoniae clone.

    Science.gov (United States)

    Hsieh, Yu-Chia; Lin, Tzu-Lung; Lin, Che-Ming; Wang, Jin-Town

    2015-07-21

    The pneumococcal genome is variable and there are minimal data on the influence of the accessory genome on phenotype. Pneumococcal serotype 14 sequence type (ST) 46 had been the most prevalent clone causing pneumonia in children in Taiwan. A microarray was constructed using the genomic DNA of a clinical strain (NTUH-P15) of serotype 14 ST46. Using DNA hybridization, genomic variations in NTUH-P15 were compared to those of 3 control strains. Microarray analysis identified 7 genomic regions that had significant increases in hybridization signals in the NTUH-P15 strain compared to control strains. One of these regions encoded PblB, a phage-encoded virulence factor implicated (in Streptococcus mitis) in infective endocarditis. The isogenic pblB mutant decreased adherence to A549 human lung epithelial cell compared to wild-type NTUH-P15 strain (P = 0.01). Complementation with pblB restored the adherence. PblB is predicted to contain a galactose-binding domain-like region. Preincubation of NTUH-P15 with D-galactose resulted in decreases of adherence to A549 cell in a dose-dependent manner. Challenge of mice with NTUH-P15, isogenic pblB mutant and pblB complementation strains determined that PblB was required for bacterial persistence in the nasopharynx and lung. PblB, as an adhesin mediating the galactose-specific adhesion activity of pneumococci, promote pneumococcal clonal success.

  9. Streptococcus pneumoniae Drugs Resistance in Acute Rhinosinusitis

    Directory of Open Access Journals (Sweden)

    Chong Jie Hao

    2016-03-01

    Full Text Available Background: Acute rhinosinusitis that usually caused by Streptococcus pneumoniae becomes the reason why patients seek for medical care. Drugs resistance in Streptococcus pneumoniae is increasing worldwide. This study was conducted to determine drugs resistance of Streptococcus pneumonia from acute rhinosinusitis in Dr. Hasan Sadikin General Hospital. Methods: A descriptive laboratory study was conducted in June–October 2014 at the Laboratory of Microbiology Faculty of Medicine Universitas Padjadjaran. The sample was taken using nasopharyngeal swabbing from 100 acute rhinosinusitis patients in Dr. Hasan Sadikin General Hospital and planted on tryptic soy agar containing 5% sheep blood and 5 μg/ml of gentamicin sulphate and then incubated in 5% CO2 incubator at 37°C for 24 hours. The identification of Streptococcus pneumonia was performed by optochin test. The susceptibility test against Streptococcus pneumoniae was done using disk diffusion method.The antibiotic disks were trimethoprim-sulfamethoxazole, oxacillin, levofloxacin, azithromycin, and doxycycline. Results: Out of 100 samples, 8 of them were tested positive for Streptococcus pneumoniae. Three of Streptococcus pneumoniae isolates died with unknown reason after it were stored at -80 .The drugs resistance test showed the resistance of Streptococcus pneumonia to oxacillin, azithromycin and trimethoprim were 6, whereas levofloxacin and doxycycline are 4. Conclusions: Streptococcus pneumonia drugs resistance in acute rhinosinusitis shows the resistance of Streptococcus pneumoniae to oxacillin, azithromycin and trimethoprim are 6, whereas the resistance to levofloxacin and doxycycline are 4.

  10. Genomewide Identification of Essential Genes and Fitness Determinants of Streptococcus mutans UA159

    Science.gov (United States)

    Zeng, Lin; Culp, David J.

    2018-01-01

    ABSTRACT Transposon mutagenesis coupled with next-generation DNA sequencing (Tn-seq) is a powerful tool for discovering regions of the genome that are required for the survival of bacteria in different environments. We adapted this technique to the dental caries pathogen Streptococcus mutans UA159 and identified 11% of the genome as essential, with many genes encoding products required for replication, translation, lipid metabolism, and cell wall biogenesis. Comparison of the essential genome of S. mutans UA159 with those of selected other streptococci for which such information is available revealed several metabolic pathways and genes that are required in S. mutans, but not in some Streptococcus spp. We further identified genes that are essential for sustained growth in rich or defined medium, as well as for persistence in vivo in a rodent model of oral infection. Collectively, our results provide a novel and comprehensive view of the genes required for essential processes of S. mutans, many of which could represent potential targets for therapeutics. IMPORTANCE Tooth decay (dental caries) is a common cause of pain, impaired quality of life, and tooth loss in children and adults. It begins because of a compositional change in the microorganisms that colonize the tooth surface driven by repeated and sustained carbohydrate intake. Although several bacterial species are associated with tooth decay, Streptococcus mutans is the most common cause. Therefore, it is important to identify biological processes that contribute to the survival of S. mutans in the human mouth, with the aim of disrupting the processes with antimicrobial agents. We successfully applied Tn-seq to S. mutans, discovering genes that are required for survival, growth, and persistence, both in laboratory environments and in a mouse model of tooth decay. This work highlights new avenues for the control of an important human pathogen. PMID:29435491

  11. Adhesion of streptococcus rattus and streptococcus mutans to metal surfaces

    International Nuclear Information System (INIS)

    Branting, C.; Linder, L.E.; Sund, M.-L.; Oden, A.; Wiatr-Adamczak, E.

    1988-01-01

    The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6- 3 H) thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria. Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26-45% of that observed in the presence of equimolar sucrose. Sucrose-dependent stimulation of adhesion seemed to be due to increased cell-to-cell adhesion capacity. Isolated radiolabeled water-insoluble and water-soluble polysaccharides produced from sucrose by S. rattus BHT were not adsorbed to the metal surfaces. (author)

  12. Adhesion of streptococcus rattus and streptococcus mutans to metal surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Branting, C.; Linder, L.E.; Sund, M.-L.; Oden, A.; Wiatr-Adamczak, E.

    1988-01-01

    The adhesion of Streptococcus rattus BHT and Streptococcus mutans IB to metal specimens of amalgam, silver, tin and copper was studied using (6-/sup 3/H) thymidine labeled cells. In the standard assay the metal specimens were suspended by a nylon thread in an adhesion solution containing a chemically defined bacterial growth medium (FMC), sucrose, and radiolabeled bacteria. Maximum amounts of adhering bacteria were obtained after about 100 min of incubation. Saturation of the metal specimens with bacteria was not observed. Both strains also adhered in the absence of sucrose, indicating that glucan formation was not necessary for adhesion. However, in the presence of glucose, adhesion was only 26-45% of that observed in the presence of equimolar sucrose. Sucrose-dependent stimulation of adhesion seemed to be due to increased cell-to-cell adhesion capacity. Isolated radiolabeled water-insoluble and water-soluble polysaccharides produced from sucrose by S. rattus BHT were not adsorbed to the metal surfaces.

  13. Effect of an alcoholic diet on dental caries and on Streptococcus of the mutans group. Study in rats.

    Science.gov (United States)

    Kantorski, Karla Zanini; de Souza, Daniela Martins; Yujra, Verônica Quispe; Junqueira, Juliana Campos; Jorge, Antonio Olavo Cardoso; da Rocha, Rosilene Fernandes

    2007-01-01

    The objective of this study was to evaluate the effects of an alcohol diet on Streptococcus of the mutans group and on dental caries in the oral cavity of rats. Forty animals were divided into 3 groups according to the following liquid diets: 20% ethanol solution (Alcohol Group, AG), 27% sucrose solution (Isocaloric Group, IG), and water (Control Group, CG). After 56 days, samples were collected and plated on Mitis Salivarius Bacitracin agar to assess the number of colony forming units (CFU/mL) of Streptococcus of the mutans group. The animals were sacrificed and the jaws were removed in order to assess the occurrence of dental caries on the smooth and occlusal surfaces using stereomicroscopy. The data were submitted to ANOVA and Tukey test. The average numbers of CFU/mL (10(3)) were: 8.17 (AG), 9.78 (IG), and 5.63 (CG). There was no significant difference among the groups for the occurrence of occlusal caries. Regarding smooth surface caries, in the upper jaw, the caries number in the IG (1.58) was similar to that in the AG (2.06) and in the CG (1.14), and the number of caries in the AG was higher than in the CG; in the lower jaw there was significant difference among the 3 groups: AG (1.14), IG (2.00) and CG (0.43). The diets with the alcohol and sucrose solutions presented a tendency of increasing the colonization by Streptococcus of the mutans group and of increasing the occurrence of smooth surface dental caries in rat molars when compared to the control diet.

  14. Phenotypical characteristics of group B streptococcus in parturients

    Directory of Open Access Journals (Sweden)

    Jose Antonio Simoes

    Full Text Available Colonization by Group B Streptococcus (GBS is highly prevalent among pregnant women, with prevalence rates ranging between 4% and 30%. The infection may be transmitted vertically and may result in serious neonatal consequences. In the period from November 2003 to May 2004, a cross-sectional study was carried out among 316 parturients at the Jundiaí Teaching Hospital to establish the prevalence of genital GBS colonization, to identify the factors associated with colonization and the characteristic phenotypes of these streptococci. Samples from rectal and vaginal areas were collected for selective culture in Todd-Hewitt broth. Susceptibility to 7 antimicrobial agents was tested using the antibiotic diffusion disk technique, and the isolated strains were classified using specific antisera. The prevalence of GBS colonization was 14.6%. No strain was resistant to penicillin, ampicillin, erythromycin or nitrofurantoin. The majority of strains were sensitive to cephalothin. Greatest resistance was to gentamicin (76.1%, followed by clindamycin (17.4%. The most frequent serotype was Ib (23.9%, followed by serotypes II and Ia (19.6% and 17.4%, respectively. There was no correlation between serotype and greater antimicrobial resistance. In conclusion, the prevalence of GBS in parturients was high and penicillin continues to be the drug of choice for intrapartum prophylaxis. The most frequent serotype (Ib found in this study differs from those found in the majority of studies carried out in other countries, revealing the need to identify prevalent serotypes in each region so that specific vaccines can be designed.

  15. Complete structure of the polysaccharide from Streptococcus sanguis J22

    International Nuclear Information System (INIS)

    Abeygunawardana, C.; Bush, C.A.; Cisar, J.O.

    1990-01-01

    The cell wall polysaccharides of certain oral streptococci such as Streptococcus sanguis strains 34 and J22, although immunologically distinct, act as receptors for the fimbrial lectins of Actinomyces viscosus T14V. The authors report the complete covalent structure of the polysaccharide from S. sanguis J22 which is composed of a heptasaccharide subunit linked by phosphodiester bonds. The repeating subunit, which contains α-GalNAc, α-rhamnose, β-rhamnose, β-glucose, and β-galactose all in the pyranoside form and β-galactofuranose, is compared with the previously published structure of the polysaccharide from strain 34. The structure has been determined almost exclusively by high-resolution nuclear magnetic resonance methods. The 1 H and 13 C NMR spectra of the polysaccharides from both strains 34 and J22 have been completely assigned. The stereochemistry of pyranosides was assigned from J H-H values determined from phase-sensitive COSY spectra, and acetamido sugars were assigned by correlation of the resonances of the amide 1 H with the sugar ring protons. The 13 C spectra were assigned by 1 H-detected multiple-quantum correlation (HMQC) spectra, and the assignments were confirmed by 1 H-detected multiple-bond correlation (HMBC) spectra. The positions of the glycosidic linkages were assigned by detection of three-bond 1 H- 13 C correlation across the glycosidic linkage in the HMBC spectra. The positions of the phosphodiester linkages were determined by splittings observed in the 13 C resonances due to 31 P coupling and also by 1 H-detected 31 P correlation spectroscopy

  16. Antibiotic Susceptibility of Periodontal Streptococcus Constellatus and Streptococcus Intermedius Clinical Isolates

    NARCIS (Netherlands)

    Rams, Thomas E; Feik, Diane; Mortensen, Joel E; Degener, John E; van Winkelhoff, Arie J

    2014-01-01

    Background: Streptococcus constellatus and Streptococcus intermedius in subgingival dental plaque biofilms may contribute to forms of periodontitis that resist treatment with conventional mechanical root debridement/surgical procedures and may additionally participate in some extraoral infections.

  17. Metformin in women with type 2 diabetes in pregnancy (MiTy): a multi-center randomized controlled trial.

    Science.gov (United States)

    Feig, Denice S; Murphy, Kellie; Asztalos, Elizabeth; Tomlinson, George; Sanchez, Johanna; Zinman, Bernard; Ohlsson, Arne; Ryan, Edmond A; Fantus, I George; Armson, Anthony B; Lipscombe, Lorraine L; Barrett, Jon F R

    2016-07-19

    The incidence of type 2 diabetes in pregnancy is rising and rates of serious adverse maternal and fetal outcomes remain high. Metformin is a biguanide that is used as first-line treatment for non-pregnant patients with type 2 diabetes. We hypothesize that metformin use in pregnancy, as an adjunct to insulin, will decrease adverse outcomes by reducing maternal hyperglycemia, maternal insulin doses, maternal weight gain and gestational hypertension/pre-eclampsia. In addition, since metformin crosses the placenta, metformin treatment of the fetus may have a direct beneficial effect on neonatal outcomes. Our aim is to compare the effectiveness of the addition of metformin to insulin, to standard care (insulin plus placebo) in women with type 2 diabetes in pregnancy. The MiTy trial is a multi-centre randomized trial currently enrolling pregnant women with type 2 diabetes, who are on insulin, between the ages of 18-45, with a gestational age of 6 weeks 0 days to 22 weeks 6 days. In this randomized, double-masked, parallel placebo-controlled trial, after giving informed consent, women are randomized to receive either metformin 1,000 mg twice daily or placebo twice daily. A web-based block randomization system is used to assign women to metformin or placebo in a 1:1 ratio, stratified for site and body mass index. The primary outcome is a composite neonatal outcome of pregnancy loss, preterm birth, birth injury, moderate/severe respiratory distress, neonatal hypoglycemia, or neonatal intensive care unit admission longer than 24 h. Secondary outcomes are large for gestational age, cord blood gas pH pregnancy, and duration of hospital stays. The trial aims to enroll 500 participants. The results of this trial will inform endocrinologists, obstetricians, family doctors, and other healthcare professionals caring for women with type 2 diabetes in pregnancy, as to the benefits of adding metformin to insulin in this high risk population. ClinicalTrials.gov Identifier: no

  18. Acid-regulated proteins induced by Streptococcus mutans and other oral bacteria during acid shock.

    Science.gov (United States)

    Hamilton, I R; Svensäter, G

    1998-10-01

    first 30 min of the acid shock, with a total of 11 acid-regulated proteins formed during the 2-h adaptation period with enhanced synthesis transient for seven of these proteins. Streptococcus salivarius AT2 and Streptococcus gordonii TH12 had the formation of 6 and 8 proteins enhanced, while the weakly responding organisms, Streptococcus sanguis ATCC 10,556 and Streptococcus oralis ATCC 10,557, exhibited 8 and 6 such proteins, respectively. Even non-responding strains unable to survive at very low pH, such as Streptococcus sobrinus CH125/43, Streptococcus mitis ATCC 12,261 and Actinomyces naeslundii 301-13 showed the initial formation of 3-9 acid-regulated proteins, but protein synthesis was not sustained over the entire adaptation period. Clearly, the survival of oral bacteria at very low pH is related, not to the total number of the acid-regulated proteins induced per se but to the formation of key proteins that function to augment normal pH homeostasis.

  19. Cross-infection between cats and cows: origin and control of Streptococcus canis mastitis in a dairy herd.

    Science.gov (United States)

    Tikofsky, L L; Zadoks, R N

    2005-08-01

    Group G streptococci in animals usually belong to the species Streptococcus canis and are most commonly found in dogs and cats. Occasionally, Strep. canis is detected in milk from dairy cows. An outbreak of Strep. canis mastitis in a dairy herd is described. Based on results from bacterial culture and ribotyping, a cat with chronic sinusitis was the most likely source of the outbreak. Subsequent cow-to-cow transmission of Strep. canis was facilitated by poor udder health management, including use of a common udder cloth and failure to use postmilking teat disinfection. Infected cows had macroscopically normal udders and milk, but significantly higher somatic cell counts than Strep. canis-negative herd mates. The outbreak was controlled through antibiotic treatment of lactating cows, early dry-off with dry cow therapy, culling of infected animals, and implementation of standard mastitis prevention measures. Cure was significantly more likely in dry-treated cows (87.5%) and cows treated during lactation (67%) than in untreated cows (9%). Whereas mastitis due to group G streptococci or Strep. canis in dairy cows is usually limited to sporadic cases of environmental (canine or feline) origin, this case study shows that crossing of the host species barrier by Strep. canis may result in an outbreak of mastitis if management conditions are conducive to contagious transmission. In such a situation, measures that are successful in control of Strep. agalactiae can also be used to control Strep. canis mastitis.

  20. Influencia de la concentración inhibitoria mínima de penicilina en la acción sinérgica de su combinación con gentamicina frente a estreptococos del grupo viridans Influence of penicillin minimal inhibitory concentration in the synergy between penicillin and gentamicin in viridans group streptococci

    Directory of Open Access Journals (Sweden)

    L. Vigliarolo

    2007-06-01

    Full Text Available Los porcentajes de resistencia a penicilina entre los estreptococos del grupo viridans han llegado a niveles superiores al 60% en algunos estudios realizados en la década pasada, y en recientes trabajos se los encontró asociados a un mayor índice de mortalidad en las bacteriemias. Aún no se conoce cuál es el nivel de concentración inhibitoria mínima de penicilina para el cual resulta imposible lograr un efecto sinérgico con algún aminoglucósido. Con este propósito, se estudió la sensibilidad a penicilina de 28 cepas de estreptococos del grupo viridans aisladas de materiales clínicamente significativos en el Hospital de Pediatría "Prof. Dr. Juan P. Garrahan". Se seleccionaron siete aislamientos pertenecientes al grupo mitis con distintas características de sensibilidad, y con ellos se ensayó la curva de muerte frente a penicilina, gentamicina y penicilina más gentamicina, con concentraciones de penicilina por encima y por debajo de su concentración inhibitoria mínima. En ningún caso se observó sinergia cuando la concentración de penicilina fue inferior a la concentración inhibitoria mínima, al menos en este grupo particular de estreptococos que presentaron concentraciones inhibitorias mínimas de gentamicina ³ 16 µg/ml. Se encontró sinergia en cinco de las siete cepas cuando se trabajó con concentraciones de penicilina superiores a la concentración inhibitoria mínima. En las otras dos, se detectaron enzimas modificadoras de aminoglucósidos.Penicillin resistance rates higher than 60% have been recorded in viridans group streptococci by some authors during the 90's and recently such resistance was associated with higher levels of mortality in bacteremia. The lowest minimal inhibitory concentration of penicillin for which synergy with aminoglycosides is not yet possible is still unknown. In order to try to dilucidate this puzzle, a study on the susceptibility to penicillin of 28 strains of viridans group streptococci

  1. First Isolation of Streptococcus halichoeri and Streptococcus phocae from a Steller Sea Lion (Eumetopias jubatus) in South Korea.

    Science.gov (United States)

    Lee, Kichan; Kim, Ji-Yeon; Jung, Suk Chan; Lee, Hee-Soo; Her, Moon; Chae, Chanhee

    2016-01-01

    Streptococcus species are emerging potential pathogens in marine mammals. We report the isolation and identification of Streptococcus halichoeri and Streptococcus phocae in a Steller sea lion (Eumetopias jubatus) in South Korea.

  2. Class II glass ionomer/silver cermet restorations and their effect on interproximal growth of mutans streptococci.

    Science.gov (United States)

    Berg, J H; Farrell, J E; Brown, L R

    1990-02-01

    The release of fluoride from glass ionomer materials is one of the most important features of this newly implemented material, and the remineralization effects of this phenomenon have been documented (Hicks and Silverstone 1986). This paper examines the effects of glass ionomer/silver cermet restorations on the plaque levels of interproximal mutans streptococci. Fifteen patients with Class II lesions in primary molars were selected for study. Interproximal plaque samples were obtained from each of the lesion sites and from one caries-free site approximal to a primary molar. One lesion was restored with composite resin to serve as a treated control to the glass ionomer/silver cermet (Ketac Silver, ESPE/Premier Sales Corp., Norristown, Pennsylvania) test site. A sound (unaltered) interproximal site served as the untreated control site. Plaque samples were collected before and at one week, one month, and three months post-treatment. Samples were serially diluted to enable colony counts of mutans streptococci. One week post-treatment counts showed that the glass ionomer/silver cermet restorations significantly reduced (P less than 0.05) the approximal plaque levels of mutans streptococci. Conversely, the untreated and treated control sites did not exhibit reductions in approximal plaque levels of mutans streptococci. These results indicate that glass ionomer restorations may be inhibitory to the growth of mutans streptococci in dental plaque approximal to this restorative material in the primary dentition.

  3. Adhesion of mutans streptococci to self-ligating ceramic brackets: in vivo quantitative analysis with real-time polymerase chain reaction.

    Science.gov (United States)

    Jung, Woo-Sun; Yang, Il-Hyung; Lim, Won Hee; Baek, Seung-Hak; Kim, Tae-Woo; Ahn, Sug-Joon

    2015-12-01

    To analyze in vivo mutans streptococci (MS) adhesion to self-ligating ceramic brackets [Clarity-SL (CSL) and Clippy-C (CC)] and the relationships between bacterial adhesion and oral hygiene indices. Four central incisor brackets from the maxilla and mandible were collected from 40 patients (20 patients per each bracket type) at debonding immediately after plaque and gingival indices were measured. Adhesions of Streptococcus mutans, S. sobrinus, and total bacteria were quantitatively determined using real-time polymerase chain reaction after genomic DNA was extracted. Factorial analysis of variance was used to analyze bacterial adhesion to the brackets with respect to the bracket type and jaw position. Correlation coefficients were calculated to determine the relationships of bacterial adhesion to oral hygiene indices. Adhesion of total bacteria and S. mutans to CSL was higher than that to CC (P brackets was higher than that to the maxillary ones (P brackets were higher than that in the mandibular ones (P brackets and jaw positions. Interestingly, no significant relationships were found between bacterial adhesions and oral hygiene indices. Complex bracket configurations may significantly influence bacterial adhesion to orthodontic brackets. Further in vivo study using bracket raw materials will help to define the relationships between bacteria adhesion and enamel demineralization. Because oral hygiene indices were not significantly correlated with adhesions of MS to self-ligating ceramic brackets, careful examinations around the brackets should be needed to prevent enamel demineralization, regardless of oral hygiene status. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  4. Epidemiology of streptococcus group A in school aged children in ...

    African Journals Online (AJOL)

    According to the epidemiology of group A streptococci and to the environmental and underlying factors which predispose to late group A streptococci sequelae, we suggest to consider antibiotic treatment for children presenting with sore throat with fever and swollen cervical lymphonodes without cough or coryza.

  5. Vaginal isolation of beta-haemolytic Streptococcus from bitches with and without neonatal deaths in the litters.

    Science.gov (United States)

    Guerrero, A E; Stornelli, M C; Jurado, S B; Giacoboni, G; Sguazza, G H; de la Sota, R L; Stornelli, M A

    2018-02-18

    The aim of the study was to identify beta-haemolytic streptococci in the vagina of bitches who had delivered healthy litters and bitches who had delivered litters in which neonatal deaths occurred. Fifty-one bitches divided into two groups were used. Group 1 (G1) included 28 bitches that had delivered healthy litters and group 2 (G2) included 23 bitches that had delivered puppies who died in the neonatal period. Two vaginal samples were taken, one in proestrus and the other at the end of gestation (EG). Beta-haemolytic Streptococcus (BS) was isolated from 16 bitches (57%) in G1 and from 21 bitches (91%) in G2. The bacteriological cultures, serological tests (Streptex ® ) and PCR assay allowed identification of Streptococcus canis and Streptococcus dysgalactiae in G1 and G2. Ultramicroscopic studies allowed the observation of M Protein and capsules in strains of S. dysgalactiae and S. canis in G1 and G2. The S. canis strains isolated from G2 showed thicker capsules than S. canis strains isolated from G1 (234 ± 24.2 vs 151.23 ± 28.93 nm; p  .70). All strains of beta-haemolytic Streptococcus isolated were penicillin sensitive. Penicillin was administered from EG to 5 days post-partum in 10 G2 females with isolation of BS (G2A). Saline solution was administered in eleven G2 females with isolation of BS (G2B). Ninety per cent of the puppies survived in G2A and 25% survived in G2B. Our results suggest BS is involved in canine neonatal deaths. © 2018 Blackwell Verlag GmbH.

  6. Molecular cloning and characterization of a Streptococcus sanguis DNase necessary for repair of DNA damage induced by UV light and methyl methanesulfonate

    International Nuclear Information System (INIS)

    Lindler, L.E.; Macrina, F.L.

    1987-01-01

    We developed a method for cloning cellular nucleases from streptococci. Recombinant lambda gt11 bacteriophage containing streptococcal nuclease determinants were identified by the production of pink plaques on toluidine blue O DNase plates. We used this technique to clone a 3.2-kilobase-pair EcoRI fragment with DNase activity from the chromosome of Streptococcus sanguis. The locus was designated don (DNase one) and could be subcloned and stably maintained on plasmid vectors in Escherichia coli. Minicell analyses of various subclones of the don locus allowed us to determine the coding region and size of the Don nuclease in E. coli. The don gene product had an apparent molecular mass of 34 kilodaltons and degraded native DNA most efficiently, with lesser activity against denatured DNA and no detectable activity against RNA. S. sanguis don deletion mutants were constructed by transformation of competent cells with in vitro-prepared plasmid constructs. S. sanguis don deletion mutants retained normal transformation frequencies for exogenously added donor DNA. However, when compared with Don+ wild-type cells, these mutants were hypersensitive to DNA damage induced by UV light and methyl methanesulfonate. An S. sanguis don-specific DNA probe detected homology to chromosomal DNA isolated from Streptococcus pneumoniae and Streptococcus mutans Bratthall serogroups d and g. Our results suggested that the don locus was the S. sanguis allele of the previously described S. pneumoniae major exonuclease and was involved in repair of DNA damage. Furthermore, hybridization studies suggested that the don locus was conserved among species of oral streptococci

  7. Comparison of two chair-side tests for enumeration of Mutans Streptococci in saliva

    DEFF Research Database (Denmark)

    Twetman, Lisa; Twetman, Svante

    2014-01-01

    AIM: To compare the prevalence and levels of salivary Mutans Streptococci (MS) assessed with two commercial chair-side methods based on culture growth or monoclonal antibodies, respectively. MATERIAL AND METHODS: The study group consisted of a convenience sample of 89 adults, 23-72 years of age......, referred to a maxillofacial hospital clinic with a caries history. Stimulated whole saliva samples were collected and the number of MS was assessed with the Dentocult-SM Strip Mutans (DSM) and the Saliva-Check Mutans (SCM). The outcome was compared with conventional anaerobic laboratory cultivation...

  8. Streptococcus tangierensis sp. nov. and Streptococcus cameli sp. nov., two novel Streptococcus species isolated from raw camel milk in Morocco.

    Science.gov (United States)

    Kadri, Zaina; Vandamme, Peter; Ouadghiri, Mouna; Cnockaert, Margo; Aerts, Maarten; Elfahime, El Mostafa; Farricha, Omar El; Swings, Jean; Amar, Mohamed

    2015-02-01

    Biochemical and molecular genetic studies were performed on two unidentified Gram-stain positive, catalase and oxidase negative, non-hemolytic Streptococcus-like organisms recovered from raw camel milk in Morocco. Phenotypic characterization and comparative 16S rRNA gene sequencing demonstrated that the two strains were highly different from each other and that they did not correspond to any recognized species of the genus Streptococcus. Phylogenetic analysis based on 16S rRNA gene sequences showed the unidentified organisms each formed a hitherto unknown sub-line within the genus Streptococcus, displaying a close affinity with Streptococcus moroccensis, Streptococcus minor and Streptococcus ovis. DNA G+C content determination, MALDI-TOF mass spectrometry and biochemical tests demonstrated the bacterial isolates represent two novel species. Based on the phenotypic distinctiveness of the new bacteria and molecular genetic evidence, it is proposed to classify the two strains as Streptococcus tangierensis sp. nov., with CCMM B832(T) (=LMG 27683(T)) as the type strain, and Streptococcus cameli sp. nov., with CCMM B834(T) (=LMG 27685(T)) as the type strain.

  9. Multiple lung abscesses caused by Streptococcus constellatus

    Directory of Open Access Journals (Sweden)

    Vanina Rognoni

    2018-02-01

    Full Text Available Despite numerous descriptions of body abscesses produced by Streptococcus milleri group bacteria, lung abscesses caused by this group remain under-reported and the clinical and laboratory features have yet to be fully characterised. We present the case of a patient admitted with lung multiple abscesses produced by Streptococcus constellatus.

  10. Group A Streptococcus vulvovaginitis in breastfeeding women.

    Science.gov (United States)

    Rahangdale, Lisa; Lacy, Judith; Hillard, Paula A

    2008-08-01

    Group A beta-hemolytic streptococcus-associated vulvovaginitis is uncommon in adult women. Clinicians should include group A beta-hemolytic streptococcus as a possible cause of vulvovaginal symptoms in breastfeeding women. Along with appropriate antibiotic therapy, vaginal estrogen therapy may be considered to diminish susceptibility to recurrent infection in women with vaginal atrophy.

  11. Streptococcus suis meningitis, a poacher's risk

    NARCIS (Netherlands)

    Halaby, T.; Hoitsma, E.; Hupperts, R.; Spanjaard, L.; Luirink, M.; Jacobs, J.

    2000-01-01

    Streptococcus suis infection is a zoonosis that has been mainly reported in pig-rearing and pork-consuming countries. The most common disease manifestation is meningitis, often associated with cochleovestibular signs. The causative agent is Streptococcus suis serotype 2, found as a commensal in the

  12. TÍTULO DE ANTIESTREPTOLISINA O Y FRECUENCIA DE ESTREPTOCOCOS BETAHEMOLÍTICOS EN ESTUDIANTES DE 10 A 15 AÑOS DEL MUNICIPIO FRANCISCO LINARES ALCÁNTARA, ESTADO ARAGUA, VENEZUELA I ASTO TITERS AND BETAHEMOLYTIC STREPTOCOCCI FREQUENCY IN 10 TO 15 YEARS OLD STUDENTS FROM MUNICIPALITY FRANCISCO LINARES ALCANTARA, ARAGUA STATE, VENEZUELA

    Directory of Open Access Journals (Sweden)

    Clara Nancy Gutierrez

    2015-07-01

    Full Text Available Beta-hemolytic streptococci of groups A (EBHGA, Streptococcus pyogenes, C (EBHGC and G (EBHGG induces the production of anti-streptolysin O antibodies (ASTO in infected individuals. In Venezuela, the most common tests used to measure these antibodies are bacterial toxins neutralizing and indirect (passive agglutination with latex particles. Individuals colonized by the aforementioned bacteria can remain as asymptomatic carriers. The purpose of this study was to determine ASO titers and frequency of beta-hemolytic streptococci in 203 students 10-15 years old from the municipality Francisco Linares Alcantara. The ASO titers were determined by neutralization and indirect (passive agglutination tests; EBH frequency was determined through the throat swab culture, which was performed on blood agar at 5%. It was found that 88.6% (180/203 and 53.2% (108/203 of the individuals had normal titers by the method of neutralization and agglutination, respectively. The most frequently isolated EBH belonged to G group (42%, followed by B (26%, A (11% and C (5% groups. There was a large discrepancy between the results from culture and serology. The Fisher exact test found no significant difference between the proportions of high titers for groups of healthy patients and asymptomatic carriers. These results indicate that the behavior of the ASTO titers is similar in both groups.

  13. The Mobile Insulin Titration Intervention (MITI) for Insulin Glargine Titration in an Urban, Low-Income Population: Randomized Controlled Trial Protocol.

    Science.gov (United States)

    Levy, Natalie; Moynihan, Victoria; Nilo, Annielyn; Singer, Karyn; Bernik, Lidia S; Etiebet, Mary-Ann; Fang, Yixin; Cho, James; Natarajan, Sundar

    2015-03-13

    Patients on insulin glargine typically visit a clinician to obtain advice on how to adjust their insulin dose. These multiple clinic visits can be costly and time-consuming, particularly for low-income patients. It may be feasible to achieve insulin titration through text messages and phone calls with patients instead of face-to-face clinic visits. The objectives of this study are to (1) evaluate if the Mobile Insulin Titration Intervention (MITI) is clinically effective by helping patients reach their optimal dose of insulin glargine, (2) determine if the intervention is feasible within the setting and population, (3) assess patient satisfaction with the intervention, and (4) measure the costs associated with this intervention. This is a pilot study evaluating an approach to insulin titration using text messages and phone calls among patients with insulin-dependent type 2 diabetes in the outpatient medical clinic of Bellevue Hospital Center, a safety-net hospital in New York City. Patients will be randomized in a 1:1 ratio to either the MITI arm (texting/phone call intervention) or the usual-care arm (in-person clinic visits). Using a Web-based platform, weekday text messages will be sent to patients in the MITI arm, asking them to text back their fasting blood glucose values. In addition to daily reviews for alarm values, a clinician will rereview the texted values weekly, consult our physician-approved titration algorithm, and call the patients with advice on how to adjust their insulin dose. The primary outcome will be whether or not a patient reaches his/her optimal dose of insulin glargine within 12 weeks. Recruitment for this study occurred between June 2013 and December 2014. We are continuing to collect intervention and follow-up data from our patients who are currently enrolled. The results of our data analysis are expected to be available in 2015. This study explores the use of widely-available text messaging and voice technologies for insulin titration

  14. Prolonged fever and involuntary weight loss as manifestations of bacterial endocarditis: A case report

    Science.gov (United States)

    Sukmawati, N. M. D. D.; Merati, T. P.; Somia, A.; Utama, S.; Gayatri, Y.

    2018-03-01

    We reported an unusual presentation of prolonged fever and involuntary weight loss in older adult as a manifestation of infective bacterial endocarditis. The patient had pre-existing compensated asymptomatic valvular heart disease without treatment. A positive fecal occult blood test is prompting an investigation of malignancy of gastrointestinal as one of other possible cause of prolonged fever with wasting, evaluation of HIV serostatus shows seronegative. The case fulfilled criteria for definitive infective endocarditis: one major criterion of positive blood culture for Streptococcus mitis, which was one of viridans group streptococci and three minor criteria of fever at least 38°Celsius, immunologic phenomena in the form of glomerulonephritis, and a predisposing heart condition. One course of third-generation cephalosporin successfully cleared the Streptococcus mitis infection proven by culture. Infective endocarditis should be considered as one of the causes of prolonged fever with wasting, especially in cases with the previous history of heart disease.

  15. RgpF Is Required for Maintenance of Stress Tolerance and Virulence in Streptococcus mutans.

    Science.gov (United States)

    Kovacs, C J; Faustoferri, R C; Quivey, R G

    2017-12-15

    Bacterial cell wall dynamics have been implicated as important determinants of cellular physiology, stress tolerance, and virulence. In Streptococcus mutans , the cell wall is composed primarily of a rhamnose-glucose polysaccharide (RGP) linked to the peptidoglycan. Despite extensive studies describing its formation and composition, the potential roles for RGP in S. mutans biology have not been well investigated. The present study characterizes the impact of RGP disruption as a result of the deletion of rgpF , the gene encoding a rhamnosyltransferase involved in the construction of the core polyrhamnose backbone of RGP. The Δ rgpF mutant strain displayed an overall reduced fitness compared to the wild type, with heightened sensitivities to various stress-inducing culture conditions and an inability to tolerate acid challenge. The loss of rgpF caused a perturbation of membrane-associated functions known to be critical for aciduricity, a hallmark of S. mutans acid tolerance. The proton gradient across the membrane was disrupted, and the Δ rgpF mutant strain was unable to induce activity of the F 1 F o ATPase in cultures grown under low-pH conditions. Further, the virulence potential of S. mutans was also drastically reduced following the deletion of rgpF The Δ rgpF mutant strain produced significantly less robust biofilms, indicating an impairment in its ability to adhere to hydroxyapatite surfaces. Additionally, the Δ rgpF mutant lost competitive fitness against oral peroxigenic streptococci, and it displayed significantly attenuated virulence in an in vivo Galleria mellonella infection model. Collectively, these results highlight a critical function of the RGP in the maintenance of overall stress tolerance and virulence traits in S. mutans IMPORTANCE The cell wall of Streptococcus mutans , the bacterium most commonly associated with tooth decay, is abundant in rhamnose-glucose polysaccharides (RGP). While these structures are antigenically distinct to S. mutans

  16. Survival, persistence, and regeneration of the reindeer lichens, Cladina stellaris, C. rangiferina, and C. mitis following clearcut logging and forest fire in northwestern Ontario

    Directory of Open Access Journals (Sweden)

    Elizabeth T. Webb

    1998-03-01

    Full Text Available The responses of the reindeer lichens (Cladina stellaris, C. rangiferina, and C. mitis to logging and fire were compared in lichen-rich forest stands in northwestern Ontario. In the summer of 1992, reindeer lichen cover, in total and by species, was visually estimated and detailed notes were taken on reindeer lichen conditions, modes of reproduction, and substrate use on 34 undisturbed, burned, or logged sites. While virtually no reindeer lichens survived forest fire, much of the reindeer lichen cover remained after logging. Reindeer lichen cover increased with time since fire. Total reindeer lichen cover was not correlated with time since logging. Fragment growth was found to be an important mode of reproduction on logged sites, and occurred with greater frequency on logged sites than on burned sites. Colonization of organic substrates by reindeer lichens was observed on both logged and burned sites.

  17. Different Erythromycin Resistance Mechanisms in Group C and Group G Streptococci

    OpenAIRE

    Kataja, Janne; Seppälä, Helena; Skurnik, Mikael; Sarkkinen, Hannu; Huovinen, Pentti

    1998-01-01

    Different mechanisms of erythromycin resistance predominate in group C and G streptococcus (GCS and GGS, respectively) isolates collected from 1992 to 1995 in Finland. Of the 21 erythromycin-resistant GCS and 32 erythromycin-resistant GGS isolates, 95% had the mefA or mefE drug efflux gene and 94% had the ermTR methylase gene, respectively.

  18. Salivary agglutinin, which binds Streptococcus mutans and Helicobacter pylori, is the lung scavenger receptor cysteine-rich protein gp-340.

    Science.gov (United States)

    Prakobphol, A; Xu, F; Hoang, V M; Larsson, T; Bergstrom, J; Johansson, I; Frängsmyr, L; Holmskov, U; Leffler, H; Nilsson, C; Borén, T; Wright, J R; Strömberg, N; Fisher, S J

    2000-12-22

    Salivary agglutinin is a high molecular mass component of human saliva that binds Streptococcus mutans, an oral bacterium implicated in dental caries. To study its protein sequence, we isolated the agglutinin from human parotid saliva. After trypsin digestion, a portion was analyzed by matrix-assisted laser/desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), which gave the molecular mass of 14 unique peptides. The remainder of the digest was subjected to high performance liquid chromatography, and the separated peptides were analyzed by MALDI-TOF/post-source decay; the spectra gave the sequences of five peptides. The molecular mass and peptide sequence information showed that salivary agglutinin peptides were identical to sequences in lung (lavage) gp-340, a member of the scavenger receptor cysteine-rich protein family. Immunoblotting with antibodies that specifically recognized either lung gp-340 or the agglutinin confirmed that the salivary agglutinin was gp-340. Immunoblotting with an antibody specific to the sialyl Le(x) carbohydrate epitope detected expression on the salivary but not the lung glycoprotein, possible evidence of different glycoforms. The salivary agglutinin also interacted with Helicobacter pylori, implicated in gastritis and peptic ulcer disease, Streptococcus agalactiae, implicated in neonatal meningitis, and several oral commensal streptococci. These results identify the salivary agglutinin as gp-340 and suggest it binds bacteria that are important determinants of either the oral ecology or systemic diseases.

  19. Comparison of antimicrobial efficacy of chlorhexidine and combination mouth rinse in reducing the Mutans streptococcus count in plaque

    Directory of Open Access Journals (Sweden)

    Laxmi S Lakade

    2014-01-01

    Full Text Available Background: The removal of plaque is utmost important to control dental caries. But in children, factors like lack of dexterity, individual motivation and monitoring limit the effectiveness of tooth brushing. This necessitates the use of chemotherapeutic agents for control of plaque. Aims: To compare the antimicrobial efficacy of 0.2% chlorhexidine mouth rinse and mouth rinse containing 0.03% triclosan, 0.05% sodium fluoride, and 5% xylitol in reducing the Mutans streptococcus count in plaque. Materials and Methods: Thirty healthy children aged 8-10 years with dmft (decay component of three or four were selected. They were divided randomly into two groups: The control or chlorhexidine group and the study group or combination mouth rinse. Both the groups practiced rinsing with respective mouth wash for 1 min for 15 d twice a day. The plaque samples were collected and after incubation Mutans streptococcus count was estimated on the strips from the Dentocult SM kit and evaluated using manufacture′s chart. Statistical Analysis Used: Wilcoxon matched pairs signed ranks test and Mann-Whitney U test were used to analyze the findings. Results: Statistically significant reduction in the Mutans streptococci count in the plaque was seen in the control and study group from baseline level. But when both the groups were compared, the antimicrobial effect of chlorhexidine was more.

  20. Co-aggregation and growth inhibition of probiotic lactobacilli and clinical isolates of mutans streptococci: An in vitro study

    DEFF Research Database (Denmark)

    Keller, Mette Kirstine; Hassl F, Pamela; Stecks N-Blicks, Christina

    2011-01-01

    -free and caries-susceptible individuals. Conclusions. The selected lactobacilli displayed co-aggregation activity and inhibited growth of clinical mutans streptococci. The growth inhibition was strain-specific and dependent on pH and cell concentration. The findings indicate that the outcome of lactobacilli...

  1. EFFECT OF XYLITOL AND SORBITOL IN CHEWING-GUMS ON MUTANS STREPTOCOCCI, PLAQUE PH AND MINERAL LOSS OF ENAMEL

    NARCIS (Netherlands)

    WENNERHOLM, K; ARENDS, J; BIRKHED, D; RUBEN, J; EMILSON, CG; DIJKMAN, AG

    1994-01-01

    Seventeen subjects with more than 3 x 10(5) mutans streptococci per millilitre of saliva completed this randomised, cross-over study. Four different chewing-gums, containing: (1) 70% xylitol, (2) 35% xylitol + 35% sorbitol, (3) 17.5% xylitol + 52.5% sorbitol, and (4) 70% sorbitol, were tested. The

  2. Antimicrobial treatment of infective endocarditis caused by viridans streptococci highly susceptible to penicillin: historic overview and future considerations

    NARCIS (Netherlands)

    Verhagen, D. W. M.; Vedder, A. C.; Speelman, P.; van der Meer, J. T. M.

    2006-01-01

    In this article we present the path that led to current concepts regarding antimicrobial treatment of endocarditis caused by viridans streptococci highly susceptible to penicillin. Early treatment trials indicate that some patients with subacute endocarditis can be cured with shorter treatment

  3. Biochemical and biological properties of the binding of human fibrinogen to M protein in group A streptococci

    International Nuclear Information System (INIS)

    Whitnack, E.; Beachey, E.H.

    1985-01-01

    Fibrinogen is known to bind to group A streptococci and precipitate with extracts containing streptococcal M protein. The authors have previously shown that the binding of fibrinogen to M-positive streptococci prevents opsonization by complement and protects that organism from phagocytosis in nonimmune blood. In the present study, they used 3 H-labeled fibrinogen, a highly purified peptide fragment of type 24 M protein (pep M24), and anti-pep M sera to show that fibrinogen binds to M-positive streptococci with high affinity; occupation of the high-affinity binding sites suffices to protect the organism from phagocytosis; proteolytic treatments that remove M protein from streptococcal cells abolish binding; binding is competitively inhibited by anti-pep M sera; pep M24 precipitates fibrinogen; and binding to type 24 cells is inhibited by pep M24. They conclude that M protein is the cell surface structure principally responsible for binding fibrinogen on the surface of M-positive streptococci and that this binding contributes to the known antiopsonic property of M proteins

  4. Radiosynthesis and biodistribution of 99mTc-tricarbonyl complex of temafloxacin dithiocarbamate. A potential Streptococci pneumoniae infection radiotracer

    International Nuclear Information System (INIS)

    Syed Qaiser Shah; Muhammad Rafiullah Khan

    2011-01-01

    In the current investigation the complexation of derivatized temafloxacin with 99m Tc using [ 99m Tc(CO) 3 (H 2 O) 3 ] + precursor was assessed. The tricarbonyl complex of the temafloxacin dithiocarbamate ( 99m Tc(CO) 3 -TAND) was characterized in terms of radiochemical purity (RCP) yield in saline, in vitro radiochemical stability in serum, in vitro binding with Streptococci pneumoniae and biodistribution in male Wister rats (MWR) artificially infected with living and heat killed Streptococci pneumoniae. The 99m Tc(CO) 3 -TAND complex showed 98.10 ± 15% RCP value at 30 min of the reconstitution and remained more than 90% stable up to 120 min in normal saline at room temperature. In serum a stable behavior with the appearance of 15.30% unwanted side product up to 16 h of incubation was observed. A saturated in vitro binding with Streptococci pneumoniae was observed. The complex showed almost six times higher uptake in the infected muscle as compared to the inflamed and normal muscles of the MWR infected with living Streptococci pneumoniae. Insignificant difference in the uptake of the tracer in the infected, inflamed and normal muscles of the MWR infected with heat killed Streptococci pneumoniae was noted. Based on the elevated RCP in saline, in vitro stability in serum at 37 deg C, saturated in vitro binding with pathogens and better biodistribution behavior with higher accumulation of the tracer in target organs confirmed the suitability of the 99m Tc(CO) 3 -TAND complex as promising infection radiotracer. (author)

  5. Structural insight into the role of Streptococcus parasanguinis Fap1 within oral biofilm formation

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, James A.; Simpson, Peter J.; Taylor, Jonathan; Benjamin, Stefi V.; Tagliaferri, Camille; Cota, Ernesto [Department of Biological Sciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom); Chen, Yi-Ywan M. [Department of Microbiology and Immunology, and Research Center for Pathogenic Bacteria, Chang Gung University, Tao-Yuan, Taiwan (China); Wu, Hui [Department of Pediatric Dentistry, University of Alabama at Birmingham, School of Dentistry, Birmingham, AL 35294 (United States); Matthews, Stephen, E-mail: s.j.matthews@imperial.ac.uk [Department of Biological Sciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ (United Kingdom)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Crystal structure of Streptococcus parasanguinis Fap1-NR{sub {alpha}} at pH 5.0. Black-Right-Pointing-Pointer pH-dependent conformational changes mediated through electrostatic potential of Fap1-NR{sub {alpha}}. Black-Right-Pointing-Pointer Fap1 facilitates pH-dependent biofilms. Black-Right-Pointing-Pointer We model inter-Fap1 biofilm interactions. -- Abstract: The fimbriae-associated protein 1 (Fap1) is a major adhesin of Streptococcus parasanguinis, a primary colonizer of the oral cavity that plays an important role in the formation of dental plaque. Fap1 is an extracellular adhesive surface fibre belonging to the serine-rich repeat protein (SRRP) family, which plays a central role in the pathogenesis of streptococci and staphylococci. The N-terminal adhesive region of Fap1 (Fap1-NR) is composed of two domains (Fap1-NR{sub {alpha}} and Fap1-NR{sub {beta}}) and is projected away from the bacterial surface via the extensive serine-rich repeat region, for adhesion to the salivary pellicle. The adhesive properties of Fap1 are modulated through a pH switch in which a reduction in pH results in a rearrangement between the Fap1-NR{sub {alpha}} and Fap1-NR{sub {beta}} domains, which assists in the survival of S. parasanguinis in acidic environments. We have solved the structure of Fap1-NR{sub {alpha}} at pH 5.0 at 3.0 A resolution and reveal how subtle rearrangements of the 3-helix bundle combined with a change in electrostatic potential mediates 'opening' and activation of the adhesive region. Further, we show that pH-dependent changes are critical for biofilm formation and present an atomic model for the inter-Fap1-NR interactions which have been assigned an important role in the biofilm formation.

  6. Structural insight into the role of Streptococcus parasanguinis Fap1 within oral biofilm formation

    International Nuclear Information System (INIS)

    Garnett, James A.; Simpson, Peter J.; Taylor, Jonathan; Benjamin, Stefi V.; Tagliaferri, Camille; Cota, Ernesto; Chen, Yi-Ywan M.; Wu, Hui; Matthews, Stephen

    2012-01-01

    Highlights: ► Crystal structure of Streptococcus parasanguinis Fap1-NR α at pH 5.0. ► pH-dependent conformational changes mediated through electrostatic potential of Fap1-NR α . ► Fap1 facilitates pH-dependent biofilms. ► We model inter-Fap1 biofilm interactions. -- Abstract: The fimbriae-associated protein 1 (Fap1) is a major adhesin of Streptococcus parasanguinis, a primary colonizer of the oral cavity that plays an important role in the formation of dental plaque. Fap1 is an extracellular adhesive surface fibre belonging to the serine-rich repeat protein (SRRP) family, which plays a central role in the pathogenesis of streptococci and staphylococci. The N-terminal adhesive region of Fap1 (Fap1-NR) is composed of two domains (Fap1-NR α and Fap1-NR β ) and is projected away from the bacterial surface via the extensive serine-rich repeat region, for adhesion to the salivary pellicle. The adhesive properties of Fap1 are modulated through a pH switch in which a reduction in pH results in a rearrangement between the Fap1-NR α and Fap1-NR β domains, which assists in the survival of S. parasanguinis in acidic environments. We have solved the structure of Fap1-NR α at pH 5.0 at 3.0 A resolution and reveal how subtle rearrangements of the 3-helix bundle combined with a change in electrostatic potential mediates ‘opening’ and activation of the adhesive region. Further, we show that pH-dependent changes are critical for biofilm formation and present an atomic model for the inter-Fap1-NR interactions which have been assigned an important role in the biofilm formation.

  7. Identification of salivary mucin MUC7 binding proteins from Streptococcus gordonii

    Directory of Open Access Journals (Sweden)

    Thornton David J

    2009-08-01

    Full Text Available Abstract Background The salivary mucin MUC7 (previously known as MG2 can adhere to various strains of streptococci that are primary colonizers and predominant microorganisms of the oral cavity. Although there is a growing interest in interaction between oral pathogens and salivary mucins, studies reporting the specific binding sites on the bacteria are rather limited. Identification and characterization of the specific interacting proteins on the bacterial cell surface, termed adhesins, are crucial to further understand host-pathogen interactions. Results We demonstrate here, using purified MUC7 to overlay blots of SDS-extracts of Streptococcus gordonii cell surface proteins, 4 MUC7-binding bands, with apparent molecular masses of 62, 78, 84 and 133 kDa from the Streptococcus gordonii strain, PK488. Putative adhesins were identified by in-gel digestion and subsequent nanoLC-tandem mass spectrometry analysis of resultant peptides. The 62 kDa and 84 kDa bands were identified as elongation factor (EF Tu and EF-G respectively. The 78 kDa band was a hppA gene product; the 74 kDa oligopeptide-binding lipoprotein. The 133 kDa band contained two proteins; alpha enolase and DNA-directed RNA polymerase, beta' subunit. Some of these proteins, for example alpha enolase are expected to be intracellular, however, flow cytometric analysis confirmed its location on the bacterial surface. Conclusion Our data demonstrated that S. gordonii expressed a number of putative MUC7 recognizing proteins and these contribute to MUC7 mucin binding of this streptococcal strain.

  8. Reduction of salivary mutans streptococci in orthodontic patients during daily consumption of yoghurt containing probiotic bacteria

    DEFF Research Database (Denmark)

    Cildir, Sule Kavaloglu; Germec, Derya; Sandalli, Nuket

    2009-01-01

    Previous studies have suggested that probiotic supplements in dairy products may affect the oral microbial ecology, but the effect in orthodontic patients has not previously been reported. The aim of the present study was to examine whether short-term consumption of fruit yogurt containing....... During periods 2 and 4 (2 weeks each), the subjects ingested 200 g fruit yogurt containing Bifidobacterium animalis subsp. lactis DN-173010 (2 x 10(8) colony forming units/g) once daily or a control yogurt without viable bacteria. Periods 1 and 3 were run-in and wash-out periods of 1 and 6 weeks......, respectively. Salivary mutans streptococci and lactobacilli were enumerated with chair-side kits before and after the yogurt consumption periods. Pre- and post-treatment values within each regimen were compared with a two-tailed marginal homogeneity test for categorical data. A statistically significant...

  9. Effect of Probiotic Curd on Salivary pH and Streptococcus mutans: A Double Blind Parallel Randomized Controlled Trial.

    Science.gov (United States)

    Srivastava, Shivangi; Saha, Sabyasachi; Kumari, Minti; Mohd, Shafaat

    2016-02-01

    Dairy products like curd seem to be the most natural way to ingest probiotics which can reduce Streptococcus mutans level and also increase salivary pH thereby reducing the dental caries risk. To estimate the role of probiotic curd on salivary pH and Streptococcus mutans count, over a period of 7 days. This double blind parallel randomized clinical trial was conducted at the institution with 60 caries free volunteers belonging to the age group of 20-25 years who were randomly allocated into two groups. Test Group consisted of 30 subjects who consumed 100ml of probiotic curd daily for seven days while an equal numbered Control Group were given 100ml of regular curd for seven days. Saliva samples were assessed at baseline, after ½ hour 1 hour and 7 days of intervention period using pH meter and Mitis Salivarius Bacitracin agar to estimate salivary pH and S. mutans count. Data was statistically analysed using Paired and Unpaired t-test. The study revealed a reduction in salivary pH after ½ hour and 1 hour in both the groups. However after 7 days, normal curd showed a statistically significant (psalivary pH while probiotic curd showed a statistically significant (psalivary pH. Similarly with regard to S. mutans colony counts probiotic curd showed statistically significant reduction (psalivary pH elevation and reduction of salivary S. mutans counts and thus can be exploited for the prevention of enamel demineralization as a long-term remedy keeping in mind its cost effectiveness.

  10. Isolation of Streptococcus spp from nile tilapia (Oreochromis niloticus and quality of water in hapas nets in North Region of Parana State, Brazil/ Isolamento de Streptococcus spp de tilápias do nilo (Oreochromis niloticus e qualidade da água de tanques rede na Região Norte do Estado do Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    Aleksey Machado Moreno

    2003-05-01

    Full Text Available This study evaluated 12 intensive breed of Nile tilapia (Oreochromis niloticus in four properties localized in the north of Parana State, Brazil. In the period of 13 months, 71 fishes were collected and analyzed of hapas nets that presenting morbidity and mortality of tilapias. Parallel, to evaluate the quality of the water of these hapas nets, there was measured the temperature, dissolved oxygen, pH, alkalinity, nitrite and ammonia. Of the 71 fishes, were collected 220 biological samples. 17 (23.94% fishes were positive for Streptococcus spp. Of the 53 biological samples from 17 fishes, in 24 (45.28% were isolated streptococci. The main clinical signs and macroscopic lesions in the fishes with isolation of Streptococcus spp. were hepatomegaly and splenomegaly, skin lesion and base of the fins and exoftalmia with cornea opacity. The higher incidence of infections caused by streptococci happened in the months with higher temperatures, mainly in the transition period winter for spring. The values of dissolved oxygen, pH, alkalinity, nitrite and ammonia of the water were normal.Foram estudados doze tanques-rede de quatro propriedades de criação intensiva de tilápia do Nilo (Oreochomis niloticus da região Norte do Paraná, Brasil. No período de 13 meses foram analisados 71 peixes provenientes de tanques apresentando morbidade e mortalidade de tilápias. Paralelamente, para avaliar a qualidade da água destes tanques, foi medida a temperatura, oxigênio dissolvido, pH, alcalinidade, nitrito e amônia. Dos 71 peixes, foram coletadas 220 materiais biológicos. Em 17 (23.94% peixes foram isolados Streptococcus spp e dos 53 materiais biológicos provenientes destes peixes, 24 (45.28% apresentaram Streptococcus spp. Os principais sinais clínicos e lesões macroscópicas nos peixes com isolamento de Streptococcus spp foram hepatomegalia e esplenomegalia, lesão de pele e base das nadadeiras e exoftalmia com opacidade de córnea. O maior número de

  11. In vitro activity of daptomycin against clinical isolates of Gram-positive bacteria.

    Science.gov (United States)

    Piper, Kerryl E; Steckelberg, James M; Patel, Robin

    2005-08-01

    We determined the activity of daptomycin, a recently FDA-approved antimicrobial agent, against clinical isolates of Gram-positive bacteria, including viridans group streptococci (16 Streptococcus mitis species group, 12 S. mutans species group, 9 S. anginosus species group, 8 S. sanguinis species group, 5 S. salivarius species group) from patients with infective endocarditis, 32 methicillin-resistant Staphylococcus aureus, 32 high-level penicillin-resistant Streptococcus pneumoniae, 38 vancomycin-resistant enterococci (including 1 linezolid-resistant isolate), and the following unusual Gram-positive bacteria: 3 Listeria monocytogenes, 4 Erysipelothrix rhusiopathiae, 9 Corynebacterium species, 10 Abiotrophia/Granulicatella species, 2 Rothia (Stomatococcus) mucilaginosus, and 4 Gemella morbillorum. Daptomycin minimum inhibitory concentration (MIC)(90) values for the viridans group streptococci, methicillin-resistant S. aureus, penicillin-resistant S. pneumoniae, and Enterococcus species were 0.5, 0.5, endocarditis as well as against several types of unusual Gram-positive bacteria that can cause endocarditis.

  12. Occurrence, isolation and DNA identification of Streptococcus ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... Streptococcus thermophilus involved in Algerian ... among reference, and wild strains of S. thermophilus and for their differentiation from Enterococcus spp. ..... Isolation and characterization of Lactobacillus delbrueckii ssp.

  13. streptococcus pneumoniae , klebsiella pneumoniae proteus vulgaris

    African Journals Online (AJOL)

    DR. AMINU

    2-20mm) on Streptococcus pneumoniae and Proteus vulgaris when compared to the ... The result from this preliminary study suggests that the plant contains active compounds that .... Veterinary and Medical Laboratory Technology, Vom,. Jos.

  14. Streptococcus pneumoniae urinary tract infection in pedeatrics.

    Science.gov (United States)

    Pougnet, Richard; Sapin, Jeanne; De Parscau, Loïc; Pougnet, Laurence

    2017-06-01

    Streptococcus pneumoniae infections in children are most often lung infections or meningitis. Urinary tract infections are much rarer. We present the case of a urinary tract infection with Streptococcus pneumoniae. The clinical picture was classical. The urine culture showed the presence of Streptococcus pneumoniae in urine (10 4 UFC/mL; with 2 × 10 4 leucocytes/mL). The literature mentions a few cases of such infections. In some studies, the prevalence of Streptococcus pneumoniae in urine of children is less than 1%. Those children mostly present abnormalities of urinary tract. In our case, urinary ultrasound scan have shown the presence of an ectopic kidney in this child. The discussion between the clinician and the biologist has contributed to the discovery of this renal anomaly.

  15. Insertional inactivation of genes responsible for the D-alanylation of lipoteichoic acid in Streptococcus gordonii DL1 (Challis) affects intrageneric coaggregations.

    Science.gov (United States)

    Clemans, D L; Kolenbrander, P E; Debabov, D V; Zhang, Q; Lunsford, R D; Sakone, H; Whittaker, C J; Heaton, M P; Neuhaus, F C

    1999-05-01

    Most human oral viridans streptococci participate in intrageneric coaggregations, the cell-to-cell adherence among genetically distinct streptococci. Two genes relevant to these intrageneric coaggregations were identified by transposon Tn916 mutagenesis of Streptococcus gordonii DL1 (Challis). A 626-bp sequence flanking the left end of the transposon was homologous to dltA and dltB of Lactobacillus rhamnosus ATCC 7469 (formerly called Lactobacillus casei). A 60-kb probe based on this flanking sequence was used to identify the homologous DNA in a fosmid library of S. gordonii DL1. This DNA encoded D-alanine-D-alanyl carrier protein ligase that was expressed in Escherichia coli from the fosmid clone. The cloned streptococcal dltA was disrupted by inserting an ermAM cassette, and then it was linearized and transformed into S. gordonii DL1 for allelic replacement. Erythromycin-resistant transformants containing a single insertion in dltA exhibited a loss of D-alanyl esters in lipoteichoic acid (LTA) and a loss of intrageneric coaggregation. This phenotype was correlated with the loss of a 100-kDa surface protein reported previously to be involved in mediating intrageneric coaggregation (C. J. Whittaker, D. L. Clemans, and P. E. Kolenbrander, Infect. Immun. 64:4137-4142, 1996). The mutants retained the parental ability to participate in intergeneric coaggregation with human oral actinomyces, indicating the specificity of the mutation in altering intrageneric coaggregations. The mutants were altered morphologically and exhibited aberrant cell septa in a variety of pleomorphs. The natural DNA transformation frequency was reduced 10-fold in these mutants. Southern analysis of chromosomal DNAs from various streptococcal species with the dltA probe revealed the presence of this gene in most viridans streptococci. Thus, it is hypothesized that D-alanyl LTA may provide binding sites for the putative 100-kDa adhesin and scaffolding for the proper presentation of this adhesin to

  16. Prevalence of Group A beta-haemolytic Streptococcus isolated from children with acute pharyngotonsillitis in Aden, Yemen.

    Science.gov (United States)

    Ba-Saddik, I A; Munibari, A A; Alhilali, A M; Ismail, S M; Murshed, F M; Coulter, J B S; Cuevas, L E; Hart, C A; Brabin, B J; Parry, C M

    2014-04-01

    To estimate the prevalence of Group A beta-haemolytic streptococcus (GAS) and non-GAS infections among children with acute pharyngotonsillitis in Aden, Yemen, to evaluate the value of a rapid diagnostic test and the McIsaac score for patient management in this setting and to determine the occurrence of emm genotypes among a subset of GAS isolated from children with acute pharyngotonsillitis and a history of acute rheumatic fever (ARF) or rheumatic heart disease (RHD). Group A beta-haemolytic streptococcus infections in school-aged children with acute pharyngotonsillitis in Aden, Yemen, were diagnosed by a rapid GAS antigen detection test (RADT) and/or GAS culture from a throat swab. The RADT value and the McIsaac screening score for patient management were evaluated. The emm genotype of a subset of GAS isolates was determined. Group A beta-haemolytic streptococcus pharyngotonsillitis was diagnosed in 287/691 (41.5%; 95% CI 37.8-45.3) children. Group B, Group C and Group G beta-haemolytic streptococci were isolated from 4.3% children. The RADT had a sensitivity of 238/258 (92.2%) and specificity of 404/423 (95.5%) against GAS culture. A McIsaac score of ≥4 had a sensitivity of 93% and a specificity of 82% for confirmed GAS infection. The emm genotypes in 21 GAS isolates from children with pharyngitis and a history of ARF and confirmed RHD were emm87 (11), emm12 (6), emm28 (3) and emm5 (1). This study demonstrates a very high prevalence of GAS infections in Yemeni children and the value of the RADT and the McIsaac score in this setting. More extensive emm genotyping is necessary to understand the local epidemiology of circulating strains. © 2014 John Wiley & Sons Ltd.

  17. Role of Streptococcus Anginosus on the formation of dental caries

    Directory of Open Access Journals (Sweden)

    Yetty Herdiyati Nonong

    2011-11-01

    Full Text Available Generally, the etiology of dental caries is the cariogenic properties of bacteria, these are always associated with Streptococcus mutans. Glucosyltransferase fragment (Gtf are also in other strains of Streptococcus such as Streptococcus anginosus, Streptococcus milleri which includes beta hemolysis. Genotypically B Streptococcus anginosus has genetic characteristics that are similar to Streptococcus mutans. The research objective was to determine the existence of Gtf B/C gene as a cause of caries in Streptococcus anginosus. The study was conducted in experimental laboratories with PCR technique by taking a sample of 20 children who had caries. The results showed there was the amplification of Streptococcus anginosus with a level of homology 96%, 97%, and 99%. The results of the Gtf genes amplification fragment B/C provided 600 pb ribbon. The conclusion was Streptococcus anginosus classified as cariogenic bacteria because they had Gtf B/C genes.

  18. The streptococcal phage SA2 and B30 endolysins act synergistically and kill mastitis causing streptococci in milk

    Science.gov (United States)

    Bovine mastitis results in billion dollar losses annually in the United States alone. Among the most relevant causative agents of this disease are members of the genus Streptococcus, particularly the species S. agalactiae (Group B Streptococcus; GBS), S. dysgalactiae (Group C; GCS), and S. uberis....

  19. Aortitis with bacteraemia by Streptococcus equi Zooepidemicus

    International Nuclear Information System (INIS)

    Betancur, Carlos Alberto; Giraldo, Juan David; Saldarriaga Eugenia Lucia

    2005-01-01

    Infections by Streptococcus equi subspecies zooepidemicus occur in animals. In human beings these infections are generally accidental, and few cases have been reported. We present the case of a 56-year-old male, a butcher, who presented with abdominal pain. Aneurismatic dilatation of the aorta below the renal arteries was documented by CT-scanning. A purulent collection and arterial ulceration were found during surgery; Streptococcus equi zooepidemicus was isolated from the collection and from blood cultures

  20. Non-invasive monitoring of Streptococcus pyogenes vaccine efficacy using biophotonic imaging.

    Directory of Open Access Journals (Sweden)

    Faraz M Alam

    Full Text Available Streptococcus pyogenes infection of the nasopharynx represents a key step in the pathogenic cycle of this organism and a major focus for vaccine development, requiring robust models to facilitate the screening of potentially protective antigens. One antigen that may be an important target for vaccination is the chemokine protease, SpyCEP, which is cell surface-associated and plays a role in pathogenesis. Biophotonic imaging (BPI can non-invasively characterize the spatial location and abundance of bioluminescent bacteria in vivo. We have developed a bioluminescent derivative of a pharyngeal S. pyogenes strain by transformation of an emm75 clinical isolate with the luxABCDE operon. Evaluation of isogenic recombinant strains in vitro and in vivo confirmed that bioluminescence conferred a growth deficit that manifests as a fitness cost during infection. Notwithstanding this, bioluminescence expression permitted non-invasive longitudinal quantitation of S. pyogenes within the murine nasopharynx albeit with a detection limit corresponding to approximately 10(5 bacterial colony forming units (CFU in this region. Vaccination of mice with heat killed streptococci, or with SpyCEP led to a specific IgG response in the serum. BPI demonstrated that both vaccine candidates reduced S. pyogenes bioluminescence emission over the course of nasopharyngeal infection. The work suggests the potential for BPI to be used in the non-invasive longitudinal evaluation of potential S. pyogenes vaccines.

  1. Detection of potentially cariogenic strains of Streptococcus mutans using the polymerase chain reaction.

    Science.gov (United States)

    Aguilera Galaviz, Luis Alejandro; Aceves Medina, Ma del Carmen; Estrada García, Iris C

    2002-01-01

    Streptococcus mutans is a pathogen related to the occurrence of human dental caries. The determination of total amounts of mutans streptococci, as well as the proportion related to other oral bacteria, is of interest when assessing the risk of developing caries. In this context, it is better to use a sensitive, specific and non-time consuming method such as the polymerase chain reaction (PCR), than to use culture and biochemical identification methods. In this work we identified potentially cariogenic strains of S. mutans and assessed the relationship with the dmft, DMFT or dmft/DMFT index. Using DNA isolated from dental plaque, a 192 bp sequence was identified and amplified from the spaP gene and a 722 bp sequence from the dexA gene. The results suggest that it is important to evaluate the presence of cariogenic S. mutans strains in plaque content rather than the accumulation of plaque itself However, other factors like diet, hygiene, genetic background, the flow rate of saliva and the presence of specific antibodies, also play a key role in the development of caries.

  2. The effect of five probiotic lactobacilli strains on the growth and biofilm formation of Streptococcus mutans.

    Science.gov (United States)

    Lin, X; Chen, X; Chen, Y; Jiang, W; Chen, H

    2015-01-01

    To compare the effects of five probiotic lactobacilli strains on the growth and biofilm formation of Streptococcus mutans (MS). Five probiotic lactobacilli bacteria (LB), Lactobacillus casei Shirota, Lactobacillus casei LC01, Lactobacillus plantarum ST-III, Lactobacillus paracasei Lpc-37, and Lactobacillus rhamnosus HN001, were used as test strains effecting on the Streptococci strain S. mutans UA159 in this study. The effect of LB strains and their supernatants on the viability of the MS was evaluated. Then, the effect of LB strains on the growth of MS biofilm formation was observed by fluorescence microscope. All of the LB strains inhibited the growth of MS at concentrations of 1 × 10(8) and 3 × 10(8) CFU ml(-1) (P strains inhibited the growth of MS (P strains inhibited the growth and biofilm formation of MS, likely through the production of an acid environment, bacteriocin-like poly peptides, or both, and the effects on MS were dependent on the LB strains used. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Streptococcus mutans copper chaperone, CopZ, is critical for biofilm formation and competitiveness.

    Science.gov (United States)

    Garcia, S S; Du, Q; Wu, H

    2016-12-01

    The oral cavity is a dynamic environment characterized by hundreds of bacterial species, saliva, and an influx of nutrients and metal ions such as copper. Although there is a physiologic level of copper in the saliva, the oral cavity is often challenged with an influx of copper ions. At high concentrations copper is toxic and must therefore be strictly regulated by pathogens for them to persist and cause disease. The cariogenic pathogen Streptococcus mutans manages excess copper using the copYAZ operon that encodes a negative DNA-binding repressor (CopY), the P1-ATPase copper exporter (CopA), and the copper chaperone (CopZ). These hypothetical roles of the copYAZ operon in regulation and copper transport to receptors led us to investigate their contribution to S. mutans virulence. Mutants defective in the copper chaperone CopZ, but not CopY or CopA, were impaired in biofilm formation and competitiveness against commensal streptococci. Characterization of the CopZ mutant biofilm revealed a decreased secretion of glucosyltransferases and reduced expression of mutacin genes. These data suggest that the function of copZ on biofilm and competitiveness is independent of copper resistance and CopZ is a global regulator for biofilm and other virulence factors. Further characterization of CopZ may lead to the identification of new biofilm pathways. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Passive Immunization with Milk Produced from an Immunized Cow Prevents Oral Recolonization by Streptococcus mutans

    Science.gov (United States)

    Shimazaki, Yoshihiro; Mitoma, Morihide; Oho, Takahiko; Nakano, Yoshio; Yamashita, Yoshihisa; Okano, Kaoru; Nakano, Yutaka; Fukuyama, Masataka; Fujihara, Noboru; Nada, Youichi; Koga, Toshihiko

    2001-01-01

    Cell surface protein antigen (PAc) and water-insoluble glucan-synthesizing enzyme (GTF-I) produced by cariogenic Streptococcus mutans are two major factors implicated in the colonization of the human oral cavity by this bacterium. We examined the effect of bovine milk, produced after immunization with a fusion protein of functional domains of these proteins, on the recolonization of S. mutans. To prepare immune milk, a pregnant Holstein cow was immunized with the fusion protein PAcA-GB, a fusion of the saliva-binding alanine-rich region (PAcA) of PAc and the glucan-binding (GB) domain of GTF-I. After eight adult subjects received cetylpyridinium chloride (CPC) treatment, one subgroup (n = 4) rinsed their mouths with immune milk and a control group (n = 4) rinsed with nonimmune milk. S. mutans levels in saliva and dental plaque decreased after CPC treatment in both groups. Mouth rinsing with immune milk significantly inhibited recolonization of S. mutans in saliva and plaque. On the other hand, the numbers of S. mutans cells in saliva and plaque in the control group increased immediately after the CPC treatment and surpassed the baseline level 42 and 28 days, respectively, after the CPC treatment. The ratios of S. mutans to total streptococci in saliva and plaque in the group that received immune milk were lower than those in the control group. These results suggest that milk produced from immunized cow may be useful for controlling S. mutans in the human oral cavity. PMID:11687453

  5. Effect of Eugenol against Streptococcus agalactiae and Synergistic Interaction with Biologically Produced Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Renata Perugini Biasi-Garbin

    2015-01-01

    Full Text Available Streptococcus agalactiae (group B streptococci (GBS is an important infections agent in newborns associated with maternal vaginal colonization. Intrapartum antibiotic prophylaxis in GBS-colonized pregnant women has led to a significant reduction in the incidence of early neonatal infection in various geographic regions. However, this strategy may lead to resistance selecting among GBS, indicating the need for new alternatives to prevent bacterial transmission and even to treat GBS infections. This study reported for the first time the effect of eugenol on GBS isolated from colonized women, alone and in combination with silver nanoparticles produced by Fusarium oxysporum (AgNPbio. Eugenol showed a bactericidal effect against planktonic cells of all GBS strains, and this effect appeared to be time-dependent as judged by the time-kill curves and viability analysis. Combination of eugenol with AgNPbio resulted in a strong synergistic activity, significantly reducing the minimum inhibitory concentration values of both compounds. Scanning and transmission electron microscopy revealed fragmented cells and changes in bacterial morphology after incubation with eugenol. In addition, eugenol inhibited the viability of sessile cells during biofilm formation and in mature biofilms. These results indicate the potential of eugenol as an alternative for controlling GBS infections.

  6. Comprehensive Evaluation of Streptococcus sanguinis Cell Wall-Anchored Proteins in Early Infective Endocarditis▿ †

    Science.gov (United States)

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L.; Wu, Hui; Kitten, Todd

    2009-01-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) approach to evaluate their contributions to virulence. Thirty-three predicted cell wall-anchored proteins were identified—a number much larger than those found in related species. The requirement of each cell wall-anchored protein for infective endocarditis was assessed in the rabbit model. It was found that no single cell wall-anchored protein was essential for the development of early infective endocarditis. STM screening was also employed for the evaluation of three predicted sortase transpeptidase enzymes, which mediate the cell surface presentation of cell wall-anchored proteins. The sortase A mutant exhibited a modest (∼2-fold) reduction in competitiveness, while the other two sortase mutants were indistinguishable from the parental strain. The combined results suggest that while cell wall-anchored proteins may play a role in S. sanguinis infective endocarditis, strategies designed to interfere with individual cell wall-anchored proteins or sortases would not be effective for disease prevention. PMID:19703977

  7. Ecto-5'-nucleotidase: a candidate virulence factor in Streptococcus sanguinis experimental endocarditis.

    Science.gov (United States)

    Fan, Jingyuan; Zhang, Yongshu; Chuang-Smith, Olivia N; Frank, Kristi L; Guenther, Brian D; Kern, Marissa; Schlievert, Patrick M; Herzberg, Mark C

    2012-01-01

    Streptococcus sanguinis is the most common cause of infective endocarditis (IE). Since the molecular basis of virulence of this oral commensal bacterium remains unclear, we searched the genome of S. sanguinis for previously unidentified virulence factors. We identified a cell surface ecto-5'-nucleotidase (Nt5e), as a candidate virulence factor. By colorimetric phosphate assay, we showed that S. sanguinis Nt5e can hydrolyze extracellular adenosine triphosphate to generate adenosine. Moreover, a nt5e deletion mutant showed significantly shorter lag time (PS. sanguinis caused IE (4 d) in a rabbit model with significantly decreased mass of vegetations (PS. sanguinis in vivo. As a virulence factor, Nt5e may function by (i) hydrolyzing ATP, a pro-inflammatory molecule, and generating adenosine, an immunosuppressive molecule to inhibit phagocytic monocytes/macrophages associated with valvular vegetations. (ii) Nt5e-mediated inhibition of platelet aggregation could also delay presentation of platelet microbicidal proteins to infecting bacteria on heart valves. Both plausible Nt5e-dependent mechanisms would promote survival of infecting S. sanguinis. In conclusion, we now show for the first time that streptococcal Nt5e modulates S. sanguinis-induced platelet aggregation and may contribute to the virulence of streptococci in experimental IE.

  8. Comprehensive evaluation of Streptococcus sanguinis cell wall-anchored proteins in early infective endocarditis.

    Science.gov (United States)

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L; Wu, Hui; Kitten, Todd

    2009-11-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) approach to evaluate their contributions to virulence. Thirty-three predicted cell wall-anchored proteins were identified-a number much larger than those found in related species. The requirement of each cell wall-anchored protein for infective endocarditis was assessed in the rabbit model. It was found that no single cell wall-anchored protein was essential for the development of early infective endocarditis. STM screening was also employed for the evaluation of three predicted sortase transpeptidase enzymes, which mediate the cell surface presentation of cell wall-anchored proteins. The sortase A mutant exhibited a modest (approximately 2-fold) reduction in competitiveness, while the other two sortase mutants were indistinguishable from the parental strain. The combined results suggest that while cell wall-anchored proteins may play a role in S. sanguinis infective endocarditis, strategies designed to interfere with individual cell wall-anchored proteins or sortases would not be effective for disease prevention.

  9. Ecto-5′-Nucleotidase: A Candidate Virulence Factor in Streptococcus sanguinis Experimental Endocarditis

    Science.gov (United States)

    Fan, Jingyuan; Zhang, Yongshu; Chuang-Smith, Olivia N.; Frank, Kristi L.; Guenther, Brian D.; Kern, Marissa; Schlievert, Patrick M.; Herzberg, Mark C.

    2012-01-01

    Streptococcus sanguinis is the most common cause of infective endocarditis (IE). Since the molecular basis of virulence of this oral commensal bacterium remains unclear, we searched the genome of S. sanguinis for previously unidentified virulence factors. We identified a cell surface ecto-5′-nucleotidase (Nt5e), as a candidate virulence factor. By colorimetric phosphate assay, we showed that S. sanguinis Nt5e can hydrolyze extracellular adenosine triphosphate to generate adenosine. Moreover, a nt5e deletion mutant showed significantly shorter lag time (PS. sanguinis caused IE (4 d) in a rabbit model with significantly decreased mass of vegetations (PS. sanguinis in vivo. As a virulence factor, Nt5e may function by (i) hydrolyzing ATP, a pro-inflammatory molecule, and generating adenosine, an immunosuppressive molecule to inhibit phagocytic monocytes/macrophages associated with valvular vegetations. (ii) Nt5e-mediated inhibition of platelet aggregation could also delay presentation of platelet microbicidal proteins to infecting bacteria on heart valves. Both plausible Nt5e-dependent mechanisms would promote survival of infecting S. sanguinis. In conclusion, we now show for the first time that streptococcal Nt5e modulates S. sanguinis-induced platelet aggregation and may contribute to the virulence of streptococci in experimental IE. PMID:22685551

  10. New Insights into the Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus Host Interaction Mechanisms.

    Directory of Open Access Journals (Sweden)

    Ana María Sánchez-Díaz

    Full Text Available Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus were classically clustered into the Lancefield Group D streptococci and despite their taxonomic reclassification still share a similar genetic content and environment. Both species are considered as opportunistic pathogens. E. faecium is often associated with nosocomial bacteraemia, and S. gallolyticus is sporadically found in endocarditis of colorectal cancer patients. In both cases, the source of infection is commonly endogenous with a translocation process that launches through the intestinal barrier. To get new insights into the pathological processes preceding infection development of both organisms, we used an in vitro model with Caco-2 cells to study and compare the adhesion, invasion and translocation inherent abilities of 6 E. faecium and 4 S. gallolyticus well-characterized isolates. Additionally, biofilm formation on polystyrene, collagen I and IV was also explored. Overall results showed that E. faecium translocated more efficiently than S. gallolyticus, inducing a destabilization of the intestinal monolayer. Isolates Efm106, Efm121 and Efm113 (p < .001 compared to Ef222 exhibited the higher translocation ability and were able to adhere 2-3 times higher than S. gallolyticus isolates. Both species preferred the collagen IV coated surfaces to form biofilm but the S. gallolyticus structures were more compact (p = .01. These results may support a relationship between biofilm formation and vegetation establishment in S. gallolyticus endocarditis, whereas the high translocation ability of E. faecium high-risk clones might partially explain the increasing number of bacteraemia.

  11. Inhibitory effect on Streptococcus mutans and mechanical properties of the chitosan containing composite resin

    Directory of Open Access Journals (Sweden)

    Ji-Sun Kim

    2013-02-01

    Full Text Available Objectives This study evaluated the antibacterial effect and mechanical properties of composite resins (LCR, MCR, HCR incorporating chitosan with three different molecular weights (L, Low; M, Medium; H, High. Materials and Methods Streptococcus (S. mutans 100 mL and each chitosan powder were inoculated in sterilized 10 mL Brain-Heart Infusion (BHI solution, and was centrifuged for 12 hr. Absorbance of the supernatent was measured at OD660 to estimate the antibacterial activities of chitosan. After S. mutans was inoculated in the disc shaped chitosan-containing composite resins, the disc was cleansed with BHI and diluted with serial dilution method. S. mutans was spread on Mitis-salivarius bacitracin agar. After then, colony forming unit (CFU was measured to verify the inhibitory effect on S. mutans biofilm. To ascertain the effect on the mechanical properties of composite resin, 3-point bending and Vickers hardness tests were done after 1 and 3 wk water storage, respectively. Using 2-way analysis of variance (ANOVA and Scheffe test, statistical analysis was done with 95% significance level. Results All chitosan powder showed inhibition effect against S. mutans. CFU number in chitosan-containing composite resins was smaller than that of control resin without chitosan. The chitosan containing composite resins did not show any significant difference in flexural strength and Vickers hardness in comparison with the control resin. However, the composite resin, MCR showed a slightly decreased flexural strength and the maximum load than those of control and the other composite resins HCR and LCR. Conclusions LCR and HCR would be recommended as a feasible antibacterial restorative due to its antibacterial nature and mechanical properties.

  12. Recommended conservation of the names Streptococcus sanguis, Streptococcus rattus, Streptococcus cricetus, and seven other names included in the Approved Lists of Bacterial Names. Request for an opinion

    DEFF Research Database (Denmark)

    Kilian, Mogens

    2001-01-01

    With reference to the first Principle of the International Code of Nomenclature of Bacteria, which emphasizes stability of names, it is proposed that the original names Streptococcus sanguis, Streptococcus rattus, Streptococcus cricetus, Erwinia ananas, Eubacterium tarantellus, Lactobacillus sake......, Nitrosococcus oceanus, Pseudomonas betle, Rickettsia canada and Streptomyces rangoon, all included in the Approved Lists of Bacterial Names, be conserved. Request for an Opinion...

  13. Effects of Lactobacillus reuteri-derived biosurfactant on the gene expression profile of essential adhesion genes (gtfB, gtfC and ftf of Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Rasoul Salehi

    2014-01-01

    Full Text Available Background: Streptococci are the main causative agents in plaque formation and mutans streptococci are the principle etiological agent of dental plaque and caries. The process of biofilm formation is a step-wise process, starting with adhesion of planktonic cells to the surfaces. It is now a well known fact that expression of glucosyltransferases (gtfs and fructosyltransferase (ftf genes play a critical role in the initial adhesion of Streptococcus mutans to the tooth surface, which results in the formation of dental plaques and consequently caries and other periodontal diseases. Materials and Methods: In the present study, we have determined the effect of biosurfactants purified from Lactobacillus reuteri (DSM20016 culture on gene expression profile of gftB/C and fft of S. mutans (ATCC35668 using quantitative real-time polymerase chain reaction. Results: The application of biosurfactant caused considerable down-regulation of the expression of all three genes under study. The reduction in gene expression was statistically very significant (P > 0.0001 for all three genes. Conclusions: Inhibition of these genes by the extracted L. reuteri biosurfactant shows the emergence of a powerful alternative to the presently practicing alternatives. In view of the importance of these gene products for S. mutans attachment to the tooth surface, which is the initial important step in biofilm production and dental caries, we believe that the biosurfactant prepared in this study could be considered as a step ahead in dental caries prevention.

  14. Functional variation of the antigen I/II surface protein in Streptococcus mutans and Streptococcus intermedius

    NARCIS (Netherlands)

    Petersen, FC; Assev, S; van der Mei, HC; Busscher, HJ; Scheie, AA

    Although Streptococcus intermedius and Streptococcus mutans are regarded as members of the commensal microflora of the body, S. intermedius is often associated with deep-seated purulent infections, whereas S. mutans is frequently associated with dental caries. In this study, we investigated the

  15. Relation of Growth of Streptococcus lactis and Streptococcus cremoris to Amino Acid Transport

    NARCIS (Netherlands)

    Poolman, Bert; Konings, Wil N.

    The maximum specific growth rate of Streptococcus lactis and Streptococcus cremoris on synthetic medium containing glutamate but no glutamine decreases rapidly above pH 7. Growth of these organisms is extended to pH values in excess of 8 in the presence of glutamine. These results can be explained

  16. Novel IgG-Degrading Enzymes of the IgdE Protease Family Link Substrate Specificity to Host Tropism of Streptococcus Species.

    Science.gov (United States)

    Spoerry, Christian; Hessle, Pontus; Lewis, Melanie J; Paton, Lois; Woof, Jenny M; von Pawel-Rammingen, Ulrich

    2016-01-01

    Recently we have discovered an IgG degrading enzyme of the endemic pig pathogen S. suis designated IgdE that is highly specific for porcine IgG. This protease is the founding member of a novel cysteine protease family assigned C113 in the MEROPS peptidase database. Bioinformatical analyses revealed putative members of the IgdE protease family in eight other Streptococcus species. The genes of the putative IgdE family proteases of S. agalactiae, S. porcinus, S. pseudoporcinus and S. equi subsp. zooepidemicus were cloned for production of recombinant protein into expression vectors. Recombinant proteins of all four IgdE family proteases were proteolytically active against IgG of the respective Streptococcus species hosts, but not against IgG from other tested species or other classes of immunoglobulins, thereby linking the substrate specificity to the known host tropism. The novel IgdE family proteases of S. agalactiae, S. pseudoporcinus and S. equi showed IgG subtype specificity, i.e. IgdE from S. agalactiae and S. pseudoporcinus cleaved human IgG1, while IgdE from S. equi was subtype specific for equine IgG7. Porcine IgG subtype specificities of the IgdE family proteases of S. porcinus and S. pseudoporcinus remain to be determined. Cleavage of porcine IgG by IgdE of S. pseudoporcinus is suggested to be an evolutionary remaining activity reflecting ancestry of the human pathogen to the porcine pathogen S. porcinus. The IgG subtype specificity of bacterial proteases indicates the special importance of these IgG subtypes in counteracting infection or colonization and opportunistic streptococci neutralize such antibodies through expression of IgdE family proteases as putative immune evasion factors. We suggest that IgdE family proteases might be valid vaccine targets against streptococci of both human and veterinary medical concerns and could also be of therapeutic as well as biotechnological use.

  17. Identification of clinically relevant nonhemolytic Streptococci on the basis of sequence analysis of 16S-23S intergenic spacer region and partial gdh gene

    DEFF Research Database (Denmark)

    Nielsen, Xiaohui Chen; Justesen, Ulrik Stenz; Dargis, Rimtas

    2009-01-01

    Nonhemolytic streptococci (NHS) cause serious infections, such as endocarditis and septicemia. Many conventional phenotypic methods are insufficient for the identification of bacteria in this group to the species level. Genetic analysis has revealed that single-gene analysis is insufficient...

  18. Antimicrobial susceptibility of streptococci from various indications of swine, horses, dogs and cats as determined in the BfT-GermVet monitoring program 2004-2006.

    Science.gov (United States)

    Schwarz, Stefan; Alesík, Eva; Grobbel, Mirjam; Lübke-Becker, Antina; Werckenthin, Christiane; Wieler, Lothar H; Wallmann, Jürgen

    2007-01-01

    A total of 500 streptococci from two indications of swine (beta-haemolytic streptococci from infections of the urinary/genital tract including strains from the mastitis metritis agalactia syndrome as well as S. suis from infections of the central nervous system and the musculoskeletal system), two indications of horses (S. equi from respiratory tract infections and beta-haemolytic streptococci from infections of the genital tract), as well as three indications of dogs and cats (beta-haemolytic streptococci from infections of the respiratory tract, the urinary/genital tract, and skin/ear/mouth) were investigated for their susceptibility to antimicrobial agents. Regardless of the animal origin and indication, the most frequently detected resistance properties were resistances against sulfamethoxazole (20-78%), tetracycline (17-93%) as well as gentamicin (14-79%). Resistance to penicillins or cephalosporins was very rarely detected - if at all.

  19. Epidemiology of intramammary infections with Staphylococcus aureus and mastitis streptococci in a dairy cattle herd with a history of recurrent clinical mastitis.

    Science.gov (United States)

    Vlkova, H; Babak, V; Vrtkova, I; Cervinkova, D; Marosevic, D; Moravkova, M; Jaglic, Z

    2017-03-28

    The aim of the present work was to examine a dairy herd with an anamnesis of recurrent clinical mastitis and decreased milk production. A total of 239 individual cow milk samples originating from asymptomatic cows were collected at four-month intervals and examined mainly for the presence of Staphylococcus aureus and mastitis streptococci using standard cultivation methods. In total, 29.7% and 9.2% samples were positive for S. aureus and mastitis streptococci, respectively. Unlike for mastitis streptococci, the prevalence of animals positive for S. aureus had an increasing trend (pmastitis, reproductive and periparturient disorders and administration of antibiotics. In contrast to S. aureus, the occurrence of mastitis streptococci in milk was linked with previous cases of clinical mastitis and intramammary administration of antibiotics.

  20. Veillonella Catalase Protects the Growth of Fusobacterium nucleatum in Microaerophilic and Streptococcus gordonii-Resident Environments.

    Science.gov (United States)

    Zhou, Peng; Li, Xiaoli; Huang, I-Hsiu; Qi, Fengxia

    2017-10-01

    The oral biofilm is a multispecies community in which antagonism and mutualism coexist among friends and foes to keep an ecological balance of community members. The pioneer colonizers, such as Streptococcus gordonii , produce H 2 O 2 to inhibit the growth of competitors, like the mutans streptococci, as well as strict anaerobic middle and later colonizers of the dental biofilm. Interestingly, Veillonella species, as early colonizers, physically interact (coaggregate) with S. gordonii A putative catalase gene ( catA ) is found in most sequenced Veillonella species; however, the function of this gene is unknown. In this study, we characterized the ecological function of catA from Veillonella parvula PK1910 by integrating it into the only transformable strain, Veillonella atypica OK5, which is catA negative. The strain (OK5- catA ) became more resistant to H 2 O 2 Further studies demonstrated that the catA gene expression is induced by the addition of H 2 O 2 or coculture with S. gordonii Mixed-culture experiments further revealed that the transgenic OK5- catA strain not only enhanced the growth of Fusobacterium nucleatum , a strict anaerobic periodontopathogen, under microaerophilic conditions, but it also rescued F. nucleatum from killing by S. gordonii A potential role of catalase in veillonellae in biofilm ecology and pathogenesis is discussed here. IMPORTANCE Veillonella species, as early colonizers, can coaggregate with many bacteria, including the initial colonizer Streptococcus gordonii and periodontal pathogen Fusobacterium nucleatum , during various stages of oral biofilm formation. In addition to providing binding sites for many microbes, our previous study also showed that Veillonella produces nutrients for the survival and growth of periodontal pathogens. These findings indicate that Veillonella plays an important "bridging" role in the development of oral biofilms and the ecology of the human oral cavity. In this study, we demonstrated that the reducing

  1. The Distribution of Mutans Streptococci in Plaque on the margin of Amalgam, on the Enamel, and on the Surface of Amalgam Restoration

    Directory of Open Access Journals (Sweden)

    Soeherwin Mangundjaja

    2015-10-01

    Full Text Available The aim of the study was to evaluate the level of distribution of mutans streptococci on the margin of amalgam restoration, compared with that on the enamel and on the surface of restoration. It is assumed that the level of distribution of mutans streptococci on the margin will be able to influence the presence of secondary caries. In this study the first molars of 20 patients were treated with amalgam restoration. The mutans streptococci was measured as the percentage of total CFU count in the plaque. The results showed a mean count of 108.8 (SD= 55.2 of mutans streptococci in the margin; 97.7 (SD=63.5 on the enamel; and 61.4 (SD=32.4 on the surface of amalgam restoration. It seems that the level of mutans streptococci on the margin is higher than those on the enamel (p=0.006 as well as higher than those on the surface of (p=0.031. It is suggested that elevated level of mutans streptococci on the margin can indicate risk to secondary caries.

  2. Detection of oral streptococci in dental unit water lines after therapy with air turbine handpiece: biological fluid retraction more frequent than expected.

    Science.gov (United States)

    Petti, Stefano; Moroni, Catia; Messano, Giuseppe Alessio; Polimeni, Antonella

    2013-03-01

    Oral streptococci detected in water from dental unit water lines (DUWLs) are a surrogate marker of patients' biological fluid retraction during therapy. We investigated oral streptococci detection rate in DUWLs in a representative sample of private offices in real-life conditions. Samples of nondisinfected water (100 ml) were collected from the DUWL designated for the air turbine handpiece in 81 dental units, immediately after dental treatment of patients with extensive air turbine handpiece use. Water was filtered and plated on a selective medium for oral streptococci and, morphologically, typical colonies of oral streptococci were counted. The lowest detection limit was 0.01 CFU/ml. The oral streptococci detection rate was 72% (95% CI: 62-81%), with a mean level of 0.7 CFU/ml. Oral streptococci detection was not affected by handpiece age or dental treatment type, but was associated with dental unit age. Biological fluid retraction into DUWLs during patient treatment and, possibly, the risk for patient-to-patient blood- or air-borne pathogen transmission are more frequent than expected.

  3. Human milk oligosaccharides inhibit growth of group B Streptococcus

    NARCIS (Netherlands)

    Lin, Ann E; Autran, Chloe A; Szyszka, Alexandra; Escajadillo, Tamara; Huang, Mia; Godula, Kamil; Prudden, Anthony R; Boons, Geert-Jan; Lewis, Amanda L; Doran, Kelly S; Nizet, Victor; Bode, Lars

    2017-01-01

    Streptococcus agalactiae (group B Streptococcus, GBS) is a leading cause of invasive bacterial infections in newborns, typically acquired vertically during childbirth secondary to maternal vaginal colonization. Human milk oligosaccharides (HMOs) have important nutritional and biological activities

  4. Rapid identification of pneumococci, enterococci, beta-haemolytic streptococci and S. aureus from positive blood cultures enabling early reports

    OpenAIRE

    Larsson, Marie C.; Karlsson, Ewa; Woksepp, Hanna; Frolander, Kerstin; Mårtensson, Agneta; Rashed, Foad; Annika, Wistedt; Schön, Thomas; Serrander, Lena

    2014-01-01

    BACKGROUND: The aim of this study was to evaluate diagnostic tests in order to introduce a diagnostic strategy to identify the most common gram-positive bacteria (pneumococci, enterococci, β-haemolytic streptococci and S. aureus) found in blood cultures within 6 hours after signalling growth. METHODS: The tube coagulase test was optimized and several latex agglutination tests were compared and evaluated before a validation period of 11 months was performed on consecutive positive blood cultur...

  5. Streptococcus agalactiae: a vaginal pathogen?

    Science.gov (United States)

    Maniatis, A N; Palermos, J; Kantzanou, M; Maniatis, N A; Christodoulou, C; Legakis, N J

    1996-03-01

    The significance of Streptococcus agalactiae as an aetiological agent in vaginitis was evaluated. A total of 6226 samples from women who presented with vaginal symptoms was examined. The presence of >10 leucocytes/high-power field (h.p.f.) was taken to be the criterion of active infection. S. agalactiae was isolated from 10.1% of these samples. The isolation rates of other common pathogens such as Candida spp., Gardnerella vaginalis and Trichomonas spp. were 54.1%, 27.2% and 4.2%, respectively, in the same group of patients. In contrast, the isolation rates of these micro-organisms in the group of patients who had no infection (S. agalactiae was isolated, it was the sole pathogen isolated (83%) and its presence was associated with an inflammatory response in 80% of patients. Furthermore, the relative risk of vaginal infection with S. agalactiae (2.38) in patients with purulent vaginal discharge was greater than that of Candida spp. infection (1.41) and lower than that of Trichomonas spp. infection (8.32). These data suggest that S. agalactiae in symptomatic women with microscopic evidence of inflammation should be considered a causative agent of vaginitis.

  6. Prevalence of Streptococcus dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus in a sample of healthy dogs, cats and horses.

    Science.gov (United States)

    Acke, E; Midwinter, A C; Lawrence, K; Gordon, S J G; Moore, S; Rasiah, I; Steward, K; French, N; Waller, A

    2015-09-01

    To estimate the prevalence of β-haemolytic Lancefield group C streptococci in healthy dogs, cats and horses; to determine if frequent contact with horses was associated with isolation of these species from dogs and cats; and to characterise recovered S. equi subsp. zooepidemicus isolates by multilocus sequence typing. Oropharyngeal swabs were collected from 197 dogs and 72 cats, and nasopharyngeal swabs from 93 horses. Sampling was carried out at the Massey University Veterinary Teaching Hospital, on sheep and beef farms or on premises where horses were present. All animals were healthy and were categorised as Urban dogs and cats (minimal contact with horses or farm livestock), Farm dogs (minimal contact with horses) and Stable dogs and cats (frequent contact with horses). Swabs were cultured for β-haemolytic Streptococcus spp. and Lancefield group C streptococcal subspecies were confirmed by phenotypic and molecular techniques. Of the 197 dogs sampled, 21 (10.7 (95% CI= 4.0-25.4)%) tested positive for S. dysgalactiae subsp. equisimilis and 4 (2.0 (95% CI=0.7-5.5)%) tested positive for S. equi subsp. zooepidemicus. All these isolates, except for one S. dysgalactiae subsp. equisimilis isolate in an Urban dog, were from Stable dogs. S. dysgalactiae subsp. equisimilis was isolated from one Stable cat. Of the 93 horses, 22 (23.7 (95% CI=12.3-40.6)%) and 6 (6.5 (95% CI=2.8-14.1)%) had confirmed S. dysgalactiae subsp. equisimilis and S. equi subsp. zooepidemicus isolation respectively. Isolation of S. dysgalactiae subsp. equisimilis from dogs was associated with frequent contact with horses (OR=9.8 (95% CI=2.6-72.8)). Three different multilocus sequence type profiles of S. equi subsp. zooepidemicus that have not been previously reported in dogs were recovered. Subclinical infection or colonisation by S. equi subsp. zooepidemicus and S. dysgalactiae subsp. equisimilis occurs in dogs and further research on inter-species transmission and the pathogenic potential of these

  7. Use of Cefazolin for Group B Streptococci Prophylaxis in Women Reporting a Penicillin Allergy Without Anaphylaxis.

    Science.gov (United States)

    Briody, Victoria A; Albright, Catherine M; Has, Phinnara; Hughes, Brenna L

    2016-03-01

    To estimate the proportion of group B streptococci (GBS)-colonized women with a reported penicillin allergy without anaphylaxis receiving appropriate intrapartum antibiotic prophylaxis. We performed a retrospective cohort study of GBS-colonized, penicillin-allergic women delivering at term receiving intrapartum antibiotic prophylaxis during labor. Scheduled cesarean deliveries were excluded. The primary outcome was the proportion of women who received appropriate antibiotic coverage, defined as penicillin or cefazolin. Secondary outcomes included neonatal outcomes such as Apgar score, blood draws, antibiotic use, length of hospital stay, and composite morbidity. Of 165 women reporting a penicillin allergy without anaphylaxis, 73 (44.2%) received an appropriate antibiotic and 92 (55.8%) received an inappropriate antibiotic. Of those receiving an inappropriate antibiotic, 56 (60.9%) were given clindamycin, 1 (1.1%) erythromycin, and 35 (38.0%) vancomycin. Women reporting rash as a penicillin reaction were more likely to receive cefazolin than another antibiotic (44 [60.3%] compared with 24 [26.1%], respectively; Ppenicillin without anaphylaxis received an antibiotic other than penicillin or cefazolin as prophylaxis, indicating poor adherence to national guidelines.

  8. Evaluation of simplified dna extraction methods for EMM typing of group a streptococci

    Directory of Open Access Journals (Sweden)

    Jose JJM

    2006-01-01

    Full Text Available Simplified methods of DNA extraction for amplification and sequencing for emm typing of group A streptococci (GAS can save valuable time and cost in resource crunch situations. To evaluate this, we compared two methods of DNA extraction directly from colonies with the standard CDC cell lysate method for emm typing of 50 GAS strains isolated from children with pharyngitis and impetigo. For this, GAS colonies were transferred into two sets of PCR tubes. One set was preheated at 94oC for two minutes in the thermal cycler and cooled while the other set was frozen overnight at -20oC and then thawed before adding the PCR mix. For the cell lysate method, cells were treated with mutanolysin and hyaluronidase before heating at 100oC for 10 minutes and cooling immediately as recommended in the CDC method. All 50 strains could be typed by sequencing the hyper variable region of the emm gene after amplification. The quality of sequences and the emm types identified were also identical. Our study shows that the two simplified DNA extraction methods directly from colonies can conveniently be used for typing a large number of GAS strains easily in relatively short time.

  9. Antimicrobial Activity of Allicin against Colonizing Group B Streptococci Isolated from Pregnant Women in Ardabil, Iran

    Directory of Open Access Journals (Sweden)

    Elham Jannati

    2014-06-01

    Full Text Available Background and Objectives: Group B streptococci (GBS are the major cause of neonatal and maternal infections. They are susceptible to penicillin, ampicillin and first-generation cephalosporins. However, resistance to other antibiotics such as erythromycin and clindamycin is common among GBS strains. The aim of this study was to evaluate the antimicrobial activity of allicin against colonizing GBS strains in vitro.   Methods: Garlic extract was prepared and allicin was purified using semi-preparative HPLC procedure. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC of allicin were determined for 52 GBS strains using microdilution method in Todd Hewitt broth medium.   Results: MIC of allicin was 64-128 µg/mL (MIC90 = 128 and MBC of allicin was 128 to 512µg/mL (MBC90 = 256 for GBS strains.   Conclusion: The results of this study showed that allicin can inhibit growth of GBS in vitro. Further studies on allicin might be worthy of evaluation as a therapeutic agent in treatment of GBS infections.

  10. Identification of Streptococcus agalactiae by fluorescent in situ hybridization compared to culturing and the determination of prevalence of Streptococcus agalactiae colonization among pregnant women in Bushehr, Iran.

    Science.gov (United States)

    Tajbakhsh, Saeed; Norouzi Esfahani, Marjan; Emaneini, Mohammad; Motamed, Niloofar; Rahmani, Elham; Gharibi, Somayyeh

    2013-09-08

    Pregnant women colonized by Streptococcus agalactiae (group B streptococci [GBS]) may transfer this microorganism to their newborns. S. agalactiae is an important cause of pneumonia, sepsis, and meningitis in newborns. Fluorescent in situ hybridization (FISH) is considered as a method of identification in the field of diagnostic microbiology. In this paper, we have designed a study to compare the DNA FISH after 7 h Lim broth enrichment and culturing for the identification of S. agalactiae and to determine the prevalence of vaginal colonization by S. agalactiae among pregnant women in Bushehr, Iran. Vaginal swab specimens were obtained from 285 pregnant women at 35 weeks or more than 35 weeks of gestation. The specimens were inoculated into Lim broth. In order to evaluate the sensitivity and specificity of GBS DNA FISH after 7 h Lim broth enrichment, the specimens were tested using both FISH and conventional culture methods. In addition, the prevalence of GBS colonization was determined. Based on the results of this study, both the sensitivity and specificity of FISH were 100%. S. agalactiae was detected by both culture and FISH in 27 of the 285 pregnant women. Thus, the prevalence of GBS colonization was 9.5%. Since short-term (7 h) Lim broth enrichment followed by FISH using oligonucleotide probes showed a high sensitivity and specificity, this protocol is therefore a highly accurate and relatively rapid method for the detection of S. agalactiae. Our analysis suggests that the use of DNA FISH to screen for S. agalactiae colonization in pregnant women may be considered in the absence of GBS culture availability.

  11. Monoclonal Idiotope Vaccine against Streptococcus pneumoniae Infection

    Science.gov (United States)

    McNamara, Mary K.; Ward, Ronald E.; Kohler, Heinz

    1984-12-01

    A monoclonal anti-idiotope antibody coupled to a carrier protein was used to immunize BALB/c mice against a lethal Streptococcus pneumoniae infection. Vaccinated mice developed a high titer of antibody to phosphorylcholine, which is known to protect against infection with Streptococcus pneumoniae. Measurement of the median lethal dose of the bacteria indicated that anti-idiotope immunization significantly increased the resistance of BALB/c mice to the bacterial challenge. Antibody to an idiotope can thus be used as an antigen substitute for the induction of protective immunity.

  12. Oral Streptococci growth on aging and non-aging esthetic restorations after radiotherapy

    International Nuclear Information System (INIS)

    Cruz, Adriana D. da; Boscolo, Frab N.; Almeida, Solange M. de; Cogo, Karina; Bergamaschi, Cristiane de C.; Groppo, Francisco C.

    2010-01-01

    The aim of this study was to examine Streptococcus mutans biofilm growth on both aged and non-aged restorative dental resins, which were submitted to therapeutic irradiation. Sixty-four disks of an esthetic restorative material (Filtek Supreme) were divided into two groups: aged group (AG) and a non-aged group (NAG). Each group was subdivided into four subgroups: non-irradiated and irradiated with 10 Gy, 35 Gy, and 70 Gy. The biofilms were produced by Streptococcus mutans UA159 growing on both AG and NAG surfaces. The colony-forming units per mL (CFU/mL) were evaluated by the ANOVA and the Tukey LSD tests (a=0.05). AG presented smaller amounts of CFU/mL than the NAG before irradiation and after 10 Gy of irradiation (p<0.05). AG irradiated with 35 and 70 Gy showed increased amount of bacterial biofilm when compared to non-irradiated and 10 Gy-irradiated disks (p<0.05). The exposure to ionizing radiation at therapeutic doses promoted changes in bacterial adherence of aged dental restorative material. (author)

  13. Oral Streptococci growth on aging and non-aging esthetic restorations after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Adriana D. da; Boscolo, Frab N.; Almeida, Solange M. de [State University of Campinas (UNICAMP), Piracicaba, SP (Brazil). Dental School. Dept. of Oral Diagnosis; Cogo, Karina; Bergamaschi, Cristiane de C.; Groppo, Francisco C., E-mail: karicogo@hotmail.co [State University of Campinas (UNICAMP), Piracicaba, SP (Brazil). Dental School. Dept. of Physiology

    2010-07-01

    The aim of this study was to examine Streptococcus mutans biofilm growth on both aged and non-aged restorative dental resins, which were submitted to therapeutic irradiation. Sixty-four disks of an esthetic restorative material (Filtek Supreme) were divided into two groups: aged group (AG) and a non-aged group (NAG). Each group was subdivided into four subgroups: non-irradiated and irradiated with 10 Gy, 35 Gy, and 70 Gy. The biofilms were produced by Streptococcus mutans UA159 growing on both AG and NAG surfaces. The colony-forming units per mL (CFU/mL) were evaluated by the ANOVA and the Tukey LSD tests (a=0.05). AG presented smaller amounts of CFU/mL than the NAG before irradiation and after 10 Gy of irradiation (p<0.05). AG irradiated with 35 and 70 Gy showed increased amount of bacterial biofilm when compared to non-irradiated and 10 Gy-irradiated disks (p<0.05). The exposure to ionizing radiation at therapeutic doses promoted changes in bacterial adherence of aged dental restorative material. (author)

  14. Characterization of biosurfactants produced by Lactobacillus spp. and their activity against oral streptococci biofilm.

    Science.gov (United States)

    Ciandrini, Eleonora; Campana, Raffaella; Casettari, Luca; Perinelli, Diego R; Fagioli, Laura; Manti, Anita; Palmieri, Giovanni Filippo; Papa, Stefano; Baffone, Wally

    2016-08-01

    Lactic acid bacteria (LAB) can interfere with pathogens through different mechanisms; one is the production of biosurfactants, a group of surface-active molecules, which inhibit the growth of potential pathogens. In the present study, biosurfactants produced by Lactobacillus reuteri DSM 17938, Lactobacillus acidophilus DDS-1, Lactobacillus rhamnosus ATCC 53103, and Lactobacillus paracasei B21060 were dialyzed (1 and 6 kDa) and characterized in term of reduction of surface tension and emulsifying activity. Then, aliquots of the different dialyzed biosurfactants were added to Streptococcus mutans ATCC 25175 and Streptococcus oralis ATCC 9811 in the culture medium during the formation of biofilm on titanium surface and the efficacy was determined by agar plate count, biomass analyses, and flow cytometry. Dialyzed biosurfactants showed abilities to reduce surface tension and to emulsifying paraffin oil. Moreover, they significantly inhibited the adhesion and biofilm formation on titanium surface of S. mutans and S. oralis in a dose-dependent way, as demonstrated by the remarkable decrease of cfu/ml values and biomass production. The antimicrobial properties observed for dialyzed biosurfactants produced by the tested lactobacilli opens future prospects for their use against microorganisms responsible of oral diseases.

  15. The accuracy of using the lytA-gene to distinguish Streptococcus pneumoniae from related species

    DEFF Research Database (Denmark)

    Greve, Thomas; Møller, Jens Kjølseth

    2012-01-01

    with primers and probes. The remaining 11 S. pneumoniae strains could be placed in a different cluster, which also contained the five S. mitis and two S. pseudopneumoniae strains. All strains had no match with primers and probes. The S. pneumoniae strains in the second cluster were all characterised by being....... The real-time PCR targeting the lytA-gene thus constitutes a sensitive and specific assay that distinguishes S. pneumoniae from its close relatives in the Mitis group....

  16. Distinct Biological Potential of Streptococcus gordonii and Streptococcus sanguinis Revealed by Comparative Genome Analysis

    OpenAIRE

    Zheng, Wenning; Tan, Mui Fern; Old, Lesley A.; Paterson, Ian C.; Jakubovics, Nicholas S.; Choo, Siew Woh

    2017-01-01

    Streptococcus gordonii and Streptococcus sanguinis are pioneer colonizers of dental plaque and important agents of bacterial infective endocarditis (IE). To gain a greater understanding of these two closely related species, we performed comparative analyses on 14 new S. gordonii and 5 S. sanguinis strains using various bioinformatics approaches. We revealed S. gordonii and S. sanguinis harbor open pan-genomes and share generally high sequence homology and number of core genes including virule...

  17. Adaptive Immunity against Streptococcus pyogenes in Adults Involves Increased IFN-gamma and IgG3 Responses Compared with Children

    DEFF Research Database (Denmark)

    Mortensen, Rasmus; Nissen, Thomas Norrelykke; Blauenfeldt, Thomas

    2015-01-01

    Each year, millions of people are infected with Streptococcus pyogenes, leading to an estimated 500,000 annual deaths worldwide. For unknown reasons, school-aged children have substantially higher infection rates than adults. The goal for this study was to provide, to our knowledge, the first det...... cellular memory response in combination with IgG1/IgG3-dominated humoral immunity that increase with age. The significance of these data regarding both the increased GAS infection rate in children and the development of protective GAS vaccines is discussed.......Each year, millions of people are infected with Streptococcus pyogenes, leading to an estimated 500,000 annual deaths worldwide. For unknown reasons, school-aged children have substantially higher infection rates than adults. The goal for this study was to provide, to our knowledge, the first...... detailed characterization of the human adaptive immune response against S. pyogenes in both children and adults. We report that all adults in our study, as well as most children, showed immunity against the two conserved group A streptococci (GAS) Ags, streptococcal C5a peptidase and immunogenic secreted...

  18. Streptococcus loxodontisalivarius sp. nov. and Streptococcus saliviloxodontae sp. nov., isolated from oral cavities of elephants.

    Science.gov (United States)

    Saito, Masanori; Shinozaki-Kuwahara, Noriko; Hirasawa, Masatomo; Takada, Kazuko

    2014-09-01

    Four Gram-stain-positive, catalase-negative, coccoid-shaped organisms were isolated from elephant oral cavities. The isolates were tentatively identified as streptococcal species based on the results of biochemical tests. Comparative 16S rRNA gene sequencing studies confirmed the organisms to be members of the genus Streptococcus. Two isolates (NUM 6304(T) and NUM 6312) were related most closely to Streptococcus salivarius with 96.8 % and 93.1 % similarity based on the 16S rRNA gene and the RNA polymerase β subunit encoding gene (rpoB), respectively, and to Streptococcus vestibularis with 83.7 % similarity based on the 60 kDa heat-shock protein gene (groEL). The other two isolates (NUM 6306(T) and NUM 6318) were related most closely to S. vestibularis with 97.0 % and 82.9 % similarity based on the 16S rRNA and groEL genes, respectively, and to S. salivarius with 93.5 % similarity based on the rpoB gene. Based on phylogenetic and phenotypic evidence, these isolates are suggested to represent novel species of the genus Streptococcus, for which the names Streptococcus loxodontisalivarius sp. nov. (type strain NUM 6304(T) = JCM 19287(T) = DSM 27382(T)) and Streptococcus saliviloxodontae sp. nov. (type strain NUM 6306(T) = JCM 19288(T) = DSM 27513(T)) are proposed. © 2014 IUMS.

  19. Streptococcus moroccensis sp. nov. and Streptococcus rifensis sp. nov., isolated from raw camel milk.

    Science.gov (United States)

    Kadri, Zaina; Amar, Mohamed; Ouadghiri, Mouna; Cnockaert, Margo; Aerts, Maarten; El Farricha, Omar; Vandamme, Peter

    2014-07-01

    Two catalase- and oxidase-negative Streptococcus-like strains, LMG 27682(T) and LMG 27684(T), were isolated from raw camel milk in Morocco. Comparative 16S rRNA gene sequencing assigned these bacteria to the genus Streptococcus with Streptococcus rupicaprae 2777-2-07(T) as their closest phylogenetic neighbour (95.9% and 95.7% similarity, respectively). 16S rRNA gene sequence similarity between the two strains was 96.7%. Although strains LMG 27682(T) and LMG 27684(T) shared a DNA-DNA hybridization value that corresponded to the threshold level for species delineation (68%), the two strains could be distinguished by multiple biochemical tests, sequence analysis of the phenylalanyl-tRNA synthase (pheS), RNA polymerase (rpoA) and ATP synthase (atpA) genes and by their MALDI-TOF MS profiles. On the basis of these considerable phenotypic and genotypic differences, we propose to classify both strains as novel species of the genus Streptococcus, for which the names Streptococcus moroccensis sp. nov. (type strain, LMG 27682(T)  = CCMM B831(T)) and Streptococcus rifensis sp. nov. (type strain, LMG 27684(T)  = CCMM B833(T)) are proposed. © 2014 IUMS.

  20. Factors associated with colonization of Streptococcus pneumoniae ...

    African Journals Online (AJOL)

    with schooling and presence chronic diseases. ... Streptococcus pneumoniae is a leading cause of serious community-acquired infections such as ... large number of individuals are still suffering from infections caused by these bacteria, especially ... samples of children with severe pneumonia (Nantanda et al., 2008).

  1. Streptococcus suis meningitis in the Netherlands

    NARCIS (Netherlands)

    van de Beek, Diederik; Spanjaard, Lodewijk; de Gans, Jan

    2008-01-01

    We present four patients with Streptococcus suis meningitis identified during a 3.5-year prospective surveillance study in the Netherlands. All cases were associated with exposure to pigs. Patients presented with classic symptoms and signs of bacterial meningitis. Outcome was characterized by severe

  2. STREPTOCOCCUS: A WORLDWIDE FISH HEALTH PROBLEM

    Science.gov (United States)

    Streptococcus iniae and S. agalactiae are important emergent pathogens that affect many fish species worldwide, especially in warm-water regions. In marine and freshwater systems, these Gram-positive bacteria cause significant economic losses, estimated at hundreds of millions of dollars annually. ...

  3. Detection and quantification of Streptococcus pneumoniae from ...

    African Journals Online (AJOL)

    The aim of this study was to develop a real time polymerase chain reaction (PCR) for quantitative detection of Streptococcus pneumoniae from clinical respiratory specimens. Initially, 184 respiratory specimens from patients with community acquired pneumonia (CAP) (n = 129) and 55 cases with hospital associated ...

  4. Antibacterial activity of Euphorbia hirta against Streptococcus ...

    African Journals Online (AJOL)

    This investigation was conducted to determine the in-vitro effect of aqueous, ethanol and methanol crude extracts of Euphorbia hirta at concentrations ranging from 10mg/ml – 100mg/ml against three pathogenic bacteria (Streptococcus pneumoniae, Klebsiella pneumoniae and Proteus vulgaris) using cup plate method.

  5. Dyrkningsnegativ Streptococcus pneumoniae endokarditis diagnosticeret med polymerasekaedereaktion

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus Vedby; Kemp, Michael; Bangsborg, Jette Marie

    2008-01-01

    A 60-year old man was admitted with sepsis and meningitis of unknown aetiology. Underlying aortic valve endocarditis was diagnosed by echocardiography and severe insufficiency led to aortic valve replacement. Application of broad-range PCR to cusp tissue revealed a DNA product, and a diagnosis of...... of Streptococcus pneumoniae endocarditis was obtained by DNA sequencing....

  6. NEW VIRULENCE FACTORS OF STREPTOCOCCUS PNEUMONIAE

    NARCIS (Netherlands)

    Hermans, Peter Wilhelmus Maria; Bootsma, Jeanette Hester; Burghout, Pieter Jan; Kuipers, Oscar; Bijlsma, Johanna Jacoba Elisabeth; Kloosterman, Tomas Gerrit; Andersen, Christian O.

    2011-01-01

    The present invention provides proteins/genes, which are essential for survival, and consequently, for virulence of Streptococcus pneumoniae in vivo, and thus are ideal vaccine candidates for a vaccine preparation against pneumococcal infection. Further, also antibodies against said protein(s) are

  7. 9230 FECAL ENTEROCOCCUS/STREPTOCOCCUS GROUPS

    Science.gov (United States)

    In 1903 the genus name Enterococcus was proposed for gram-positive, catalase-negative, coccoid-shaped bacterial of intestinal origin. Several years later, it was suggested that the genus name be changed to Streptococcus because of the organisms' ability to form chains of coccoid...

  8. Salivary levels of mutans streptococci and Lactobacilli among Palestinian school children in East Jerusalem.

    Science.gov (United States)

    Steinberg, Doron; Eskander, Lana; Zini, Avraham; Sgan-Cohen, Harold; Bajali, Musa

    2014-04-01

    The aim of the present study was to investigate the distribution of oral cariogenic bacteria among 12-year-old Palestinian children attending schools in East Jerusalem. Salivary levels of mutans streptococci (MS) and Lactobacilli (LB) were examined by semi-quantitative commercial kits and then correlated to social-demographic parameters. Overall, 52.1 % of the examined children presented the highest possible ranking score categories for MS bacteria, with only 5.4 % in the lowest category. Only 12.6 % of the school children presented the highest LB score, while 25 % had the lowest ranking score. Salivary MS levels in children attending private schools were lower than those of children in government schools and United Nations Relief and Works Agency (UNRWA) schools. Conversely, levels of LB were lowest in children attending UNRWA schools compared to government and private schools. Girls had significantly higher amounts of MS and LB than boys (p = 0.001). Lower MS levels were significantly related to the following socioeconomic variables: higher father's education level (p = 0.037), higher mother's education level (p = 0.063), mother's employment status (p = 0.012), and lower home density (p = 0.001). For LB, the only significant socioeconomic variable was higher father's employment level, which was related to lower LB level (p = 0.025). Levels of MS and LB were found to be strongly related with socioeconomic status among Palestinian children in East Jerusalem. The relatively high prevalence of cariogenic bacteria suggests that oral care prevention and treatment demands special attention from the health care institutions and authorities.

  9. Frequency of Group B Streptococci in Pregnant Women in a Tertiary Care Hospital

    International Nuclear Information System (INIS)

    Munir, S. I.; Waheed, K.; Khanum, A.; Iqbal, R.; Eusaph, A. Z.; Hanif, A.

    2016-01-01

    Objective: To determine the frequency and risk factors of Group B Streptococci (GBS) in pregnant patients in third trimester in a tertiary care hospital in Lahore. Study Design: Cross-sectional, prospective study. Place and Duration of Study: Lady Willingdon Hospital, Lahore, from October 2014 to March 2015. Methodology: Sterile lower vaginal swabs were taken from 200 women aged 20 years and over, in third trimester, with no history of vaginal bleeding, ruptured membrane, recent intake of antibiotics or chronic illness. These swabs were cultured for detection of GBS. The risk factors of GBS and its frequency were noted in the pregnant population. Quantitative and qualitative data was analyzed by SPSS version 20. Chi-square test was applied to see association between diagnosis of GBS and other categorical variables. P-value 0.05 was considered as statistically significant. Results: In this study, the mean age of all the females was 26.36 ±4.32 years and mean duration of pregnancy was 35.54 ±2.65 weeks. Frequency of GBS in pregnant women was found as 14 percentage. We observed significant association of GBS with parity and previous history of miscarriage (p-value = 0.033 and 0.010 respectively). Moreover, significant association between vaginal discharge and GBS was also found (p = 0.027). Conclusion: GBS is present in a small but significant number of pregnant women in our setting and it has association with multiparity, vaginal discharge during pregnancy, and previous history of miscarriage. (author)

  10. Plasticity of the Pyruvate Node Modulates Hydrogen Peroxide Production and Acid Tolerance in Multiple Oral Streptococci.

    Science.gov (United States)

    Cheng, Xingqun; Redanz, Sylvio; Cullin, Nyssa; Zhou, Xuedong; Xu, Xin; Joshi, Vrushali; Koley, Dipankar; Merritt, Justin; Kreth, Jens

    2018-01-15

    Commensal Streptococcus sanguinis and Streptococcus gordonii are pioneer oral biofilm colonizers. Characteristic for both is the SpxB-dependent production of H 2 O 2 , which is crucial for inhibiting competing biofilm members, especially the cariogenic species Streptococcus mutans H 2 O 2 production is strongly affected by environmental conditions, but few mechanisms are known. Dental plaque pH is one of the key parameters dictating dental plaque ecology and ultimately oral health status. Therefore, the objective of the current study was to characterize the effects of environmental pH on H 2 O 2 production by S. sanguinis and S. gordonii S. sanguinis H 2 O 2 production was not found to be affected by moderate changes in environmental pH, whereas S. gordonii H 2 O 2 production declined markedly in response to lower pH. Further investigation into the pyruvate node, the central metabolic switch modulating H 2 O 2 or lactic acid production, revealed increased lactic acid levels for S. gordonii at pH 6. The bias for lactic acid production at pH 6 resulted in concomitant improvement in the survival of S. gordonii at low pH and seems to constitute part of the acid tolerance response of S. gordonii Differential responses to pH similarly affect other oral streptococcal species, suggesting that the observed results are part of a larger phenomenon linking environmental pH, central metabolism, and the capacity to produce antagonistic amounts of H 2 O 2 IMPORTANCE Oral biofilms are subject to frequent and dramatic changes in pH. S. sanguinis and S. gordonii can compete with caries- and periodontitis-associated pathogens by generating H 2 O 2 Therefore, it is crucial to understand how S. sanguinis and S. gordonii adapt to low pH and maintain their competitiveness under acid stress. The present study provides evidence that certain oral bacteria respond to environmental pH changes by tuning their metabolic output in favor of lactic acid production, to increase their acid survival

  11. Microbial Diversity in Milk of Women With Mastitis: Potential Role of Coagulase-Negative Staphylococci, Viridans Group Streptococci, and Corynebacteria.

    Science.gov (United States)

    Mediano, Pilar; Fernández, Leonides; Jiménez, Esther; Arroyo, Rebeca; Espinosa-Martos, Irene; Rodríguez, Juan M; Marín, María

    2017-05-01

    Lactational mastitis constitutes a significant cause of premature weaning. However, its etiology, linked to the presence of pathogenic microorganisms, has been scarcely reported. Research aim: The aim of this study was to describe the microbial diversity in milk samples from women suffering from lactational mastitis and to identify more accurately a collection of isolates belonging to coagulase-negative staphylococci, streptococci, and coryneform bacteria. This is a cross-sectional descriptive one-group study. A total of 5,009 isolates from 1,849 mastitis milk samples was identified by culture, biochemical, and/or molecular methods at the species or genus level. A more precise identification of a collection of 211 isolates was carried out by 16S rRNA gene sequencing. Mean total bacterial count in milk samples was 4.11 log 10 colony-forming units/ml, 95% confidence interval [4.08, 4.15]. Staphylococcus epidermidis was the most common species being isolated from 91.56% of the samples, whereas Staphylococcus aureus was detected in 29.74%. Streptococci and corynebacteria constituted the second (70.20%) and third (16.60%) most prevalent bacterial groups, respectively, found in this study. In contrast, Candida spp. was present in only 0.54% of the samples. Sequencing of the 16S rRNA gene revealed a high diversity of bacterial species among identified isolates. Many coagulase-negative staphylococci, viridans group streptococci, and corynebacteria, usually dismissed as contaminant bacteria, may play an important role as etiologic agents of mastitis. Proper diagnosis of mastitis should be established after performing microbiological testing of milk based on standardized procedures. A reliable analysis must identify the mastitis-causing pathogen(s) at the species level and its(their) concentration(s).

  12. Deletion of Repeats in the Alpha C Protein Enhances the Pathogenicity of Group B Streptococci in Immune Mice

    OpenAIRE

    Gravekamp, C.; Rosner, Bernard; Madoff, L. C.

    1998-01-01

    The alpha C protein is a protective surface-associated antigen of group B streptococci (GBS). The prototype alpha C protein of GBS (strain A909) contains nine identical tandem repeats, each comprising 82 amino acids, flanked by N- and C-terminal domains. Clinical isolates of GBS show variable numbers of repeats with a normal distribution and a median of 9 to 10 repeats. Here, we show that escape mutants of GBS expressing one-repeat alpha C protein were 100-fold more pathogenic than GBS expres...

  13. Cariogram outcome after 90 days of oral treatment with Streptococcus salivarius M18 in children at high risk for dental caries: results of a randomized, controlled study

    Directory of Open Access Journals (Sweden)

    Di Pierro F

    2015-10-01

    Full Text Available Francesco Di Pierro,1 Alberto Zanvit,2 Piero Nobili,2 Paolo Risso,3 Carlo Fornaini4 1Scientific Department, Velleja Research, 2Stomatology Institute, Milan, Italy; 3Department of Health Science, University of Genoa, Genoa, Italy; 4Teleo Laboratory, Faculty of Dentistry, University of Nice, Nice, France Abstract: Dental caries is the most common chronic disease of childhood. Cariogram is a well-recognized algorithm-based software program based on different caries-related risk factors and intended to aid clinicians in performing more objective and consistent dental caries risk assessments. This type of approach precedes the diagnosis of caries and allows the dentist to identify at-risk patients and then take appropriate preventive measures before caries develop further. One of the etiological factors favoring the development of dental caries is the mutans streptococci. These acidogenic dental plaque inhabitants can be effectively antagonized by the activity of bacteriocins released by the probiotic Streptococcus salivarius M18 (salivarius M18. Moreover, salivarius M18 after colonizing the human oral mucosa produces the enzymes dextranase and urease that are able to counteract plaque formation and saliva acidity, respectively. Seventy-six subjects at high risk of dental caries were randomized and then either treated or not treated for 90 days with an oral formulation containing the oral probiotic salivarius M18 (Carioblis®. The results indicate that the use of salivarius M18 increases the chances of avoiding new dental caries development in children, and its application could be proposed as a new tool in the dentist's armory to be adopted in subjects considered at high risk on the basis of their Cariogram outcome. Keywords: BLIS M18, caries prediction, dextranase, urease, Streptococcus mutans, Streptococcus sobrinus, plaque, salivary pH, bacteriocins

  14. Genotypic characterization of initial acquisition of Streptococcus mutans in American Indian children

    Directory of Open Access Journals (Sweden)

    David J. Lynch

    2015-04-01

    Full Text Available Background: Severe-early childhood caries (S-ECC is one of the most common infectious diseases in children and is prevalent in lower socio-economic populations. American Indian children suffer from the highest levels of S-ECC in the United States. Members of the mutans streptococci, Streptococcus mutans, in particular, are key etiologic agents in the development of caries. Children typically acquire S. mutans from their mothers and early acquisition is often associated with higher levels of tooth decay. Methods: We have conducted a 5-year birth cohort study with a Northern Plains Tribe to determine the temporality and fidelity of S. mutans transmission from mother to child in addition to the genotypic diversity of S. mutans in this community. Plaque samples were collected from 239 mother/child dyads at regular intervals from birth to 36 months and S. mutans were isolated and genotyped by arbitrarily primed-polymerase chain reaction (AP-PCR. Results: Here we present preliminary findings from a subset of the cohort. The focus for this paper is on initial acquisition events in the children. We identified 17 unique genotypes in 711 S. mutans isolates in our subset of 40 children, 40 mothers and 14 primary caregivers. Twelve of these genotypes were identified in more than one individual. S. mutans colonization occurred by 16 months in 57.5% of the children and early colonization was associated with higher decayed, missing and filled surface (DMFS scores (p=0.0007. Children colonized by S. mutans shared a common genotype with their mothers 47.8% of the time. While multiple genotypes were common in adults, only 10% of children harbored multiple genotypes. Conclusion: These children acquire S. mutans at an earlier age than the originally described ‘window of infectivity’ and often, but not exclusively, from their mothers. Early acquisition is associated with both the caries status of the children and the mothers.

  15. Detection of Group B Streptococcus in Brazilian pregnant women and antimicrobial susceptibility patterns

    Directory of Open Access Journals (Sweden)

    Didier Silveira Castellano-Filho

    2010-12-01

    Full Text Available Group B Streptococcus (GBS is still not routinely screened during pregnancy in Brazil, being prophylaxis and empirical treatment based on identification of risk groups. This study aimed to investigate GBS prevalence in Brazilian pregnant women by culture or polymerase chain reaction (PCR associated to the enrichment culture, and to determine the antimicrobial susceptibility patterns of isolated bacteria, so as to support public health policies and empirical prophylaxis. After an epidemiological survey, vaginal and anorectal specimens were collected from 221 consenting laboring women. Each sample was submitted to enrichment culture and sheep blood agar was used to isolate suggestive GBS. Alternatively, specific PCR was performed from enrichment cultures. Antimicrobial susceptibility patterns were determined for isolated bacteria by agar diffusion method. No risk groups were identified. Considering the culture-based methodology, GBS was detected in 9.5% of the donors. Twenty five bacterial strains were isolated and identified. Through the culture-PCR methodology, GBS was detected in 32.6% specimens. Bacterial resistance was not detected against ampicillin, cephazolin, vancomycin and ciprofloxacin, whereas 22.7% were resistant to erythromycin and 50% were resistant to clindamycin. GBS detection may be improved by the association of PCR and enrichment culture. Considering that colony selection in agar plates may be laboring and technician-dependent, it may not reflect the real prevalence of streptococci. As in Brazil prevention strategies to reduce the GBS associated diseases have not been adopted, prospective studies are needed to anchor public health policies especially considering the regional GBS antimicrobial susceptibility patterns.

  16. Crystallization and preliminary X-ray diffraction analysis of phosphoglycerate kinase from Streptococcus pneumoniae

    International Nuclear Information System (INIS)

    Bernardo-García, Noelia; Bartual, Sergio G.; Fulde, Marcus; Bergmann, Simone; Hermoso, Juan A.

    2011-01-01

    Phosphoglycerate kinase, a two-domain enzyme involved in the glycolytic pathway, has been crystallized. Both the N-terminal domain and a ternary complex of the full-length enzyme with substrates were crystallized by the sitting-drop vapour-diffusion method. Inclusion of the substrates was critical in order to obtain crystals of the full-length protein. Phosphoglycerate kinase (PGK) is a widespread two-domain enzyme that plays a critical role in the glycolytic pathway. Several glycolytic enzymes from streptococci have been identified as surface-exposed proteins that are involved in streptococcal virulence by their ability to bind host proteins. This binding allows pneumococcal cells to disseminate through the epithelial and endothelial layers. Crystallization of PGK from Streptococcus pneumoniae yielded orthorhombic crystals (space group I222, unit-cell parameters a = 62.73, b = 75.38, c = 83.63 Å). However, the unit cell of these crystals was not compatible with the presence of full-length PGK. Various analytical methods showed that only the N-terminal domain of PGK was present in the I222 crystals. The ternary complex of PGK with adenylyl imidodiphosphate (AMP-PNP) and 3-phospho-d-glycerate (3PGA) produced monoclinic crystals (space group P2 1 , unit-cell parameters a = 40.35, b = 78.23, c = 59.03 Å, β = 96.34°). Molecular replacement showed that this new crystal form contained full-length PGK, thereby indicating the relevance of including substrates in order to avoid proteolysis during the crystallization process

  17. Identification and characterization of an autolysin-encoding gene of Streptococcus mutans.

    Science.gov (United States)

    Shibata, Yukie; Kawada, Miki; Nakano, Yoshio; Toyoshima, Kuniaki; Yamashita, Yoshihisa

    2005-06-01

    We identified a gene (atlA) encoding autolytic activity from Streptococcus mutans Xc. The AtlA protein predicted to be encoded by atlA is composed of 979 amino acids with a molecular weight of 107,279 and has a conserved beta-1,4-N-acetylmuramidase (lysozyme) domain in the C-terminal portion. Sodium dodecyl sulfate extracts of strain Xc showed two major bacteriolytic bands with molecular masses of 107 and 79 kDa, both of which were absent from a mutant with inactivated atlA. Western blot analysis revealed that the 79-kDa band was derived from the 107-kDa peptide by cleavage of its N-terminal portion. The inactivation of atlA resulted in a marked decrease in autolysis and the formation of very long chains of cells compared to the case for the parent strain. Although both the parent and mutant strains formed biofilms in the presence of sucrose, the biofilms formed by the mutant had a sponge-like architecture with large gaps and contained 30% less biomass than those formed by the parent strain. Furthermore, strain Xc formed glucose-dependent, loose biofilms in the absence of sucrose, but the mutant lost this ability. These results suggest that AtlA may play an important role in biofilm formation by S. mutans. The antibody produced against the C-terminal peptide containing the beta-1,4-N-acetylmuramidase domain drastically inhibited the autolytic activity of strain Xc. This inhibition was specific among the oral streptococci to S. mutans. These results indicate that the catalytic domain of AtlA is located at the C terminus, suggesting that further characterization of this domain may provide a means to control cariogenic dental plaque formation.

  18. Alanine racemase is essential for the growth and interspecies competitiveness of Streptococcus mutans.

    Science.gov (United States)

    Wei, Yuan; Qiu, Wei; Zhou, Xue-Dong; Zheng, Xin; Zhang, Ke-Ke; Wang, Shi-Da; Li, Yu-Qing; Cheng, Lei; Li, Ji-Yao; Xu, Xin; Li, Ming-Yun

    2016-12-16

    D-alanine (D-Ala) is an essential amino acid that has a key role in bacterial cell wall synthesis. Alanine racemase (Alr) is a unique enzyme that interconverts L-alanine and D-alanine in most bacteria, making this enzyme a potential target for antimicrobial drug development. Streptococcus mutans is a major causative factor of dental caries. The factors involved in the survival, virulence and interspecies interactions of S. mutans could be exploited as potential targets for caries control. The current study aimed to investigate the physiological role of Alr in S. mutans. We constructed alr mutant strain of S. mutans and evaluated its phenotypic traits and interspecies competitiveness compared with the wild-type strain. We found that alr deletion was lethal to S. mutans. A minimal supplement of D-Ala (150 μg·mL -1 ) was required for the optimal growth of the alr mutant. The depletion of D-alanine in the growth medium resulted in cell wall perforation and cell lysis in the alr mutant strain. We also determined the compromised competitiveness of the alr mutant strain relative to the wild-type S. mutans against other oral streptococci (S. sanguinis or S. gordonii), demonstrated using either conditioned medium assays or dual-species fluorescent in situ hybridization analysis. Given the importance and necessity of alr to the growth and competitiveness of S. mutans, Alr may represent a promising target to modulate the cariogenicity of oral biofilms and to benefit the management of dental caries.

  19. Molecular Characterization of Streptococcus agalactiae Causing Community- and Hospital-acquired Infections in Shanghai, China

    Directory of Open Access Journals (Sweden)

    Haoqin Jiang

    2016-08-01

    Full Text Available Streptococcus agalactiae, a colonizing agent in pregnant women and the main cause of neonatal sepsis and meningitis, has been increasingly associated with invasive disease in nonpregnant adults. We collected a total of 87 non-repetitive S. agalactiae isolates causing community-acquired (CA and hospital-acquired (HA infections in nonpregnant adults from a teaching hospital in Shanghai between 2009 and 2013. We identified and characterized their antibiotic resistance, sequence type (ST, serotype, virulence, and biofilm formation. The most frequent STs were ST19 (29.9%, ST23 (16.1%, ST12 (13.8%, and ST1 (12.6%. ST19 had significantly different distributions between CA- and HA-group B Streptococci (GBS isolates. The most frequent serotypes were III (32.2%, Ia (26.4%, V (14.9%, Ib (13.8%, and II (5.7%. Serotype III/ST19 was significantly associated with levofloxacin resistance in all isoates. The HA-GBS multidrug resistant rate was much higher than that of CA-GBS. Virulence genes pavA, cfb were found in all isolates. Strong correlations exist between serotype Ib (CA and HA and surface protein genes spb1 and bac, serotype III (HA and surface protein gene cps and GBS pilus cluster. The serotype, epidemic clone, PFGE-based genotype, and virulence gene are closely related between CA-GBS and HA-GBS, and certain serotypes and clone types were significantly associated with antibiotic resistance. However, CA-GBS and HA-GBS still had significant differences in their distribution of clone types, antibiotic resistance, and specific virulence genes, which may provide a basis for infection control.

  20. Ecto-5'-nucleotidase: a candidate virulence factor in Streptococcus sanguinis experimental endocarditis.

    Directory of Open Access Journals (Sweden)

    Jingyuan Fan

    Full Text Available Streptococcus sanguinis is the most common cause of infective endocarditis (IE. Since the molecular basis of virulence of this oral commensal bacterium remains unclear, we searched the genome of S. sanguinis for previously unidentified virulence factors. We identified a cell surface ecto-5'-nucleotidase (Nt5e, as a candidate virulence factor. By colorimetric phosphate assay, we showed that S. sanguinis Nt5e can hydrolyze extracellular adenosine triphosphate to generate adenosine. Moreover, a nt5e deletion mutant showed significantly shorter lag time (P<0.05 to onset of platelet aggregation than the wild-type strain, without affecting platelet-bacterial adhesion in vitro (P=0.98. In the absence of nt5e, S. sanguinis caused IE (4 d in a rabbit model with significantly decreased mass of vegetations (P<0.01 and recovered bacterial loads (log(10CFU, P=0.01, suggesting that Nt5e contributes to the virulence of S. sanguinis in vivo. As a virulence factor, Nt5e may function by (i hydrolyzing ATP, a pro-inflammatory molecule, and generating adenosine, an immunosuppressive molecule to inhibit phagocytic monocytes/macrophages associated with valvular vegetations. (ii Nt5e-mediated inhibition of platelet aggregation could also delay presentation of platelet microbicidal proteins to infecting bacteria on heart valves. Both plausible Nt5e-dependent mechanisms would promote survival of infecting S. sanguinis. In conclusion, we now show for the first time that streptococcal Nt5e modulates S. sanguinis-induced platelet aggregation and may contribute to the virulence of streptococci in experimental IE.

  1. Commensal Streptococcus salivarius Modulates PPARγ Transcriptional Activity in Human Intestinal Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Benoît Couvigny

    Full Text Available The impact of commensal bacteria in eukaryotic transcriptional regulation has increasingly been demonstrated over the last decades. A multitude of studies have shown direct effects of commensal bacteria from local transcriptional activity to systemic impact. The commensal bacterium Streptococcus salivarius is one of the early bacteria colonizing the oral and gut mucosal surfaces. It has been shown to down-regulate nuclear transcription factor (NF-кB in human intestinal cells, a central regulator of the host mucosal immune system response to the microbiota. In order to evaluate its impact on a further important transcription factor shown to link metabolism and inflammation in the intestine, namely PPARγ (peroxisome proliferator-activated receptor, we used human intestinal epithelial cell-lines engineered to monitor PPARγ transcriptional activity in response to a wide range of S. salivarius strains. We demonstrated that different strains from this bacterial group share the property to inhibit PPARγ activation independently of the ligand used. First attempts to identify the nature of the active compounds showed that it is a low-molecular-weight, DNase-, proteases- and heat-resistant metabolite secreted by S. salivarius strains. Among PPARγ-targeted metabolic genes, I-FABP and Angptl4 expression levels were dramatically reduced in intestinal epithelial cells exposed to S. salivarius supernatant. Both gene products modulate lipid accumulation in cells and down-regulating their expression might consequently affect host health. Our study shows that species belonging to the salivarius group of streptococci impact both host inflammatory and metabolic regulation suggesting a possible role in the host homeostasis and health.

  2. Streptococcus mutans SpaP binds to RadD of Fusobacterium nucleatum ssp. polymorphum.

    Science.gov (United States)

    Guo, Lihong; Shokeen, Bhumika; He, Xuesong; Shi, Wenyuan; Lux, Renate

    2017-10-01

    Adhesin-mediated bacterial interspecies interactions are important elements in oral biofilm formation. They often occur on a species-specific level, which could determine health or disease association of a biofilm community. Among the key players involved in these processes are the ubiquitous fusobacteria that have been recognized for their ability to interact with numerous different binding partners. Fusobacterial interactions with Streptococcus mutans, an important oral cariogenic pathogen, have previously been described but most studies focused on binding to non-mutans streptococci and specific cognate adhesin pairs remain to be identified. Here, we demonstrated differential binding of oral fusobacteria to S. mutans. Screening of existing mutant derivatives indicated SpaP as the major S. mutans adhesin specific for binding to Fusobacterium nucleatum ssp. polymorphum but none of the other oral fusobacteria tested. We inactivated RadD, a known adhesin of F. nucleatum ssp. nucleatum for interaction with a number of gram-positive species, in F. nucleatum ssp. polymorphum and used a Lactococcus lactis heterologous SpaP expression system to demonstrate SpaP interaction with RadD of F. nucleatum ssp. polymorphum. This is a novel function for SpaP, which has mainly been characterized as an adhesin for binding to host proteins including salivary glycoproteins. In conclusion, we describe an additional role for SpaP as adhesin in interspecies adherence with RadD-SpaP as the interacting adhesin pair for binding between S. mutans and F. nucleatum ssp. polymorphum. Furthermore, S. mutans attachment to oral fusobacteria appears to involve species- and subspecies-dependent adhesin interactions. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Evaluation of procedures for typing of group B Streptococcus: a retrospective study

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    Hans-Christian Slotved

    2017-03-01

    Full Text Available Background This study evaluates two procedures for typing of Streptococcus agalactiae (group B streptococci; GBS isolates, using retrospective typing data from the period 2010 to 2014 with a commercial latex agglutination test (latex test and the Lancefield precipitation test (LP test. Furthermore, the genotype distribution of phenotypically non-typable (NT GBS isolates is presented. We also raise the awareness, that the difference in typing results obtained by phenotypical methods and genotype based methods may have implications on vaccine surveillance in case a GBS vaccine is introduced. Methods A total of 616 clinical GBS isolates from 2010 to 2014 were tested with both a latex test and the LP test. Among these, 66 isolates were genotyped by PCR, including 41 isolates that were phenotypically NT. Results The latex test provided a serotype for 83.8% of the isolates (95% CI [80.7–86.6] compared to 87.5% (95% CI [84.6–90.0] obtained by the LP method. The two assays provided identical capsular identification for all sero-typeable isolates (excluding NT isolates. The PCR assay provided a genotype designation to the 41 isolates defined as phenotypically NT isolates. Discussion We found that the latex test showed a slightly lower identification percentage than the LP test. Our recommendation is to use the latex agglutination as the routine primary assay for GBS surveillance, and then use the more labour intensive precipitation test on the NT isolates to increase the serotyping rate. A genotype could be assigned to all the phenotypically NT isolates, however, as a consequence genotyping will overestimate the coverage from possible future capsular polysaccharide based GBS vaccines.

  4. Comparative genomic characterization of three Streptococcus parauberis strains in fish pathogen, as assessed by wide-genome analyses.

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    Seong-Won Nho

    Full Text Available Streptococcus parauberis, which is the main causative agent of streptococcosis among olive flounder (Paralichthys olivaceus in northeast Asia, can be distinctly divided into two groups (type I and type II by an agglutination test. Here, the whole genome sequences of two Japanese strains (KRS-02083 and KRS-02109 were determined and compared with the previously determined genome of a Korean strain (KCTC 11537. The genomes of S. parauberis are intermediate in size and have lower GC contents than those of other streptococci. We annotated 2,236 and 2,048 genes in KRS-02083 and KRS-02109, respectively. Our results revealed that the three S. parauberis strains contain different genomic insertions and deletions. In particular, the genomes of Korean and Japanese strains encode different factors for sugar utilization; the former encodes the phosphotransferase system (PTS for sorbose, whereas the latter encodes proteins for lactose hydrolysis, respectively. And the KRS-02109 strain, specifically, was the type II strain found to be able to resist phage infection through the clustered regularly interspaced short palindromic repeats (CRISPR/Cas system and which might contribute valuably to serologically distribution. Thus, our genome-wide association study shows that polymorphisms can affect pathogen responses, providing insight into biological/biochemical pathways and phylogenetic diversity.

  5. The AgI/II family adhesin AspA is required for respiratory infection by Streptococcus pyogenes.

    Directory of Open Access Journals (Sweden)

    Linda Franklin

    Full Text Available Streptococcus pyogenes (GAS is a human pathogen that causes pharyngitis and invasive diseases such as toxic shock syndrome and sepsis. The upper respiratory tract is the primary reservoir from which GAS can infect new hosts and cause disease. The factors involved in colonisation are incompletely known however. Previous evidence in oral streptococci has shown that the AgI/II family proteins are involved. We hypothesized that the AspA member of this family might be involved in GAS colonization. We describe a novel mouse model of GAS colonization of the nasopharynx and lower respiratory tract to elucidate these interactions. We used two clinical M serotypes expressing AspA, and their aspA gene deletant isogenic mutants in experiments using adherence assays to respiratory epithelium, macrophage phagocytosis and neutrophil killing assays and in vivo models of respiratory tract colonisation and infection. We demonstrated the requirement for AspA in colonization of the respiratory tract. AspA mutants were cleared from the respiratory tract and were deficient in adherence to epithelial cells, and susceptible to phagocytosis. Expression of AspA in the surrogate host Lactococcus lactis protected bacteria from phagocytosis. Our results suggest that AspA has an essential role in respiratory infection, and may function as a novel anti-phagocytic factor.

  6. Co-infection of Acipenserid herpesvirus 2 (AciHV-2) and Streptococcus iniae in cultured white sturgeon Acipenser transmontanus.

    Science.gov (United States)

    Soto, Esteban; Richey, Christine; Stevens, Brittany; Yun, Susan; Kenelty, Kirsten; Reichley, Stephen; Griffin, Matt; Kurobe, Tomofumi; Camus, Al

    2017-03-30

    A mortality event in cultured white sturgeon Acipenser transmontanus (Richardson, 1836) sub-adults was investigated. After transfer between farms, high mortality was observed in fish, associated with back arching, abnormal swimming, and ulcerative skin lesions. Necropsy of moribund individuals revealed hemorrhagic ascites and petechial hemorrhages in the coelomic peritoneum and serosa of internal organs. Acipenserid herpesvirus 2 (AciHV-2) was isolated from external tissue samples, then identified and genotyped by sequencing of the terminase and polymerase genes. In addition, Streptococcus iniae was recovered from internal organs of affected fish. Histologic changes were limited to interstitial hematopoietic areas of the kidney and consisted of small foci of necrosis accompanied by fibrin deposition, minimal inflammatory response, and small numbers of bacterial cocci compatible with streptococci. Identity was confirmed by partial sequencing of the 16S rRNA, rpoB, and gyrB genes. Genetic fingerprinting demonstrated a genetic profile distinct from S. iniae isolates recovered from previous outbreaks in wild and cultured fish in North America, South America, and the Caribbean. Although the isolates were resistant to white sturgeon complement in serum killing assays, in vivo challenges failed to fulfill Koch's postulates. However, the clinical presentation, coupled with consistent recovery of S. iniae and AciHV-2 from moribund fish, suggests viral and bacterial co-infection were the proximate cause of death. To our knowledge, this represents the first report of AciHV-2 and S. iniae co-infection in cultured white sturgeon.

  7. LocZ Is a New Cell Division Protein Involved in Proper Septum Placement in Streptococcus pneumoniae

    Science.gov (United States)

    Holečková, Nela; Molle, Virginie; Buriánková, Karolína; Benada, Oldřich; Kofroňová, Olga; Ulrych, Aleš; Branny, Pavel

    2014-01-01

    ABSTRACT How bacteria control proper septum placement at midcell, to guarantee the generation of identical daughter cells, is still largely unknown. Although different systems involved in the selection of the division site have been described in selected species, these do not appear to be widely conserved. Here, we report that LocZ (Spr0334), a newly identified cell division protein, is involved in proper septum placement in Streptococcus pneumoniae. We show that locZ is not essential but that its deletion results in cell division defects and shape deformation, causing cells to divide asymmetrically and generate unequally sized, occasionally anucleated, daughter cells. LocZ has a unique localization profile. It arrives early at midcell, before FtsZ and FtsA, and leaves the septum early, apparently moving along with the equatorial rings that mark the future division sites. Consistently, cells lacking LocZ also show misplacement of the Z-ring, suggesting that it could act as a positive regulator to determine septum placement. LocZ was identified as a substrate of the Ser/Thr protein kinase StkP, which regulates cell division in S. pneumoniae. Interestingly, homologues of LocZ are found only in streptococci, lactococci, and enterococci, indicating that this close phylogenetically related group of bacteria evolved a specific solution to spatially regulate cell division. PMID:25550321

  8. Acquisition through Horizontal Gene Transfer of Plasmid pSMA198 by Streptococcus macedonicus ACA-DC 198 Points towards the Dairy Origin of the Species

    Science.gov (United States)

    Papadimitriou, Konstantinos; Anastasiou, Rania; Maistrou, Eleni; Plakas, Thomas; Papandreou, Nikos C.; Hamodrakas, Stavros J.; Ferreira, Stéphanie; Supply, Philip; Renault, Pierre; Pot, Bruno; Tsakalidou, Effie

    2015-01-01

    Background Streptococcus macedonicus is an intriguing streptococcal species whose most frequent source of isolation is fermented foods similarly to Streptococcus thermophilus. However, S. macedonicus is closely related to commensal opportunistic pathogens of the Streptococcus bovis/Streptococcus equinus complex. Methodology/Principal Findings We analyzed the pSMA198 plasmid isolated from the dairy strain Streptococcus macedonicus ACA-DC 198 in order to provide novel clues about the main ecological niche of this bacterium. pSMA198 belongs to the narrow host range pCI305/pWV02 family found primarily in lactococci and to the best of our knowledge it is the first such plasmid to be reported in streptococci. Comparative analysis of the pSMA198 sequence revealed a high degree of similarity with plasmids isolated from Lactococcus lactis strains deriving from milk or its products. Phylogenetic analysis of the pSMA198 Rep showed that the vast majority of closely related proteins derive from lactococcal dairy isolates. Additionally, cloning of the pSMA198 ori in L. lactis revealed a 100% stability of replication over 100 generations. Both pSMA198 and the chromosome of S. macedonicus exhibit a high percentage of potential pseudogenes, indicating that they have co-evolved under the same gene decay processes. We identified chromosomal regions in S. macedonicus that may have originated from pSMA198, also supporting a long co-existence of the two replicons. pSMA198 was also found in divergent biotypes of S. macedonicus and in strains isolated from dispersed geographic locations (e.g. Greece and Switzerland) showing that pSMA198’s acquisition is not a recent event. Conclusions/Significance Here we propose that S. macedonicus acquired plasmid pSMA198 from L. lactis via an ancestral genetic exchange event that took place most probably in milk or dairy products. We provide important evidence that point towards the dairy origin of this species. PMID:25584532

  9. Adhesive Properties and Acid-Forming Activity of Lactobacilli and Streptococci Under Inhibitory Substances, Such as Nitrates.

    Science.gov (United States)

    Hakobyan, L; Harutyunyan, K; Harutyunyan, N; Melik-Andreasyan, G; Trchounian, A

    2016-06-01

    One of the main requirements for probiotics is their ability to survive during passage through gastrointestinal tract and to maintain their activity at different adverse conditions. The aim of the study was to look for the strains of lactobacilli and streptococci with high adhesive properties even affected by inhibitory substances, such as nitrates (NO3 (-)). To study the adhesion properties hemagglutination reaction of bacterial cells with red blood cells of different animals and humans was used. The acid formation ability of bacteria was determined by the method of titration after 7 days of incubation in the sterile milk. These properties were investigated at different concentrations of NO3 (-). The high concentration (mostly ≥2.0 %) NO3 (-) inhibited the growth of both lactobacilli and streptococci, but compared with streptococcal cultures lactobacilli, especially Lactobacillus acidophilus Ep 317/402, have shown more stability and higher adhesive properties. In addition, the concentrations of NO3 (-) of 0.5-2.0 % decreased the acid-forming activity of the strains, but even under these conditions they coagulated milk and, in comparison to control, formed low acidity in milk. Thus, the L. acidophilus Ep 317/402 with high adhesive properties has demonstrated a higher activity of NO3 (-) transformation.

  10. Seeing Streptococcus pneumoniae, a Common Killer Bacteria

    DEFF Research Database (Denmark)

    Kjærgaard, Rikke Schmidt; Andersen, Ebbe Sloth

    2014-01-01

    Look around you. The diversity and complexity of life on earth is overwhelming and data continues to grow. In our desire to understand and explain everything scientifically from molecular evolution to supernovas we depend on visual representations. This paper investigates visual representations...... of the bacteria Streptococcus pneumoniae by use of ink, watercolours and computer graphics. We propose a novel artistic visual rendering of Streptococcus pneumoniae and ask what the value of these kind of representations are compared to traditional scientific data. We ask if drawings and computer......-assisted representations can add to our scientific knowledge about this dangerous bacteria. Is there still a role for the scientific illustrator in the scientific process and synthesis of scientific knowledge?...

  11. Infective Endocarditis: Identification of Catalase-Negative, Gram-Positive Cocci from Blood Cultures by Partial 16S rRNA Gene Analysis and by Vitek 2 Examination

    DEFF Research Database (Denmark)

    Abdul-Redha, Rawaa Jalil; Kemp, Michael; Bangsborg, Jette M

    2010-01-01

    Streptococci, enterococci and Streptococcus-like bacteria are frequent etiologic agents of infective endocarditis and correct species identification can be a laboratory challenge. Viridans streptococci (VS) not seldomly cause contamination of blood cultures. Vitek 2 and partial sequencing of the 16......S rRNA gene were applied in order to compare the results of both methods. STRAINS ORIGINATED FROM TWO GROUPS OF PATIENTS: 149 strains from patients with infective endocarditis and 181 strains assessed as blood culture contaminants. Of the 330 strains, based on partial 16S rRNA gene sequencing......-agreeing identifications with the two methods with respect to allocation to the same VS group. Non-agreeing species identification mostly occurred among strains in the contaminant group, while for endocarditis strains notably fewer disagreeing results were observed.Only 67 of 150 strains in the mitis group strains...

  12. Serological Evidence of Immune Priming by Group A Streptococci in Patients with Acute Rheumatic Fever

    Directory of Open Access Journals (Sweden)

    Jeremy M Raynes

    2016-07-01

    Full Text Available Acute rheumatic fever (ARF is an autoimmune response to Group A Streptococcus (GAS infection. Repeated GAS exposures are proposed to ‘prime’ the immune system for autoimmunity. This notion of immune-priming by multiple GAS infections was first postulated in the 1960s, but direct experimental evidence to support the hypothesis has been lacking. Here we present novel methodology, based on antibody responses to GAS T‑antigens, that enables previous GAS exposures to be mapped in patient sera. T-antigens are surface expressed, type specific antigens and GAS strains fall into 18 major clades or T-types. A panel of recombinant T-antigens was generated and immunoassays were performed in parallel with serum depletion experiments allowing type-specific T‑antigen antibodies to be distinguished from cross-reactive antibodies. At least two distinct GAS exposures were detected in each of the ARF sera tested. Furthermore, no two sera had the same T-antigen reactivity profile suggesting that each patient was exposed to a unique series of GAS T‑types prior to developing ARF. The methods have provided much-needed experimental evidence to substantiate the immune-priming hypothesis, and will facilitate further serological profiling studies that explore the multifaceted interactions between GAS and the host.

  13. [Streptococcus suis infection--clinical manifestations].

    Science.gov (United States)

    Dragojlović, Julijana; Milosević, Branko; Sasić, Neda; Pelemis, Mijomir; Sasić, Milan

    2005-01-01

    Streptococcus suis is a bacterium causing a disease in pigs and rarely in humans. This zoonosis is mostly found as a sporadic disease in individuals that were in contact with the affected or infected pigs: farmers, veterinarians and workers engaged in fresh pork processing. It is assumed that the bacterium enters the body through a cut abrasion in the skin. Initially, the condition resembles a flu, followed by signs of bacteriemia and sepsis. The most frequent clinical manifestation of Streptococcus suis infection is meningitis, leading to hearing loss in over 75% of patients, and subsequent arthritis, endophtalmitis, endocarditis and pneumonia. Toxic shock syndrome with hemorhagic manifestations rarely develops. This study included five male patients aged 22 to 63 years treated in the Intensive Care Unit of the Institute of Infectious and Tropical Diseases in Belgrade, due to Streptococcus suis infection. The aim of this study was to point to the existence of this bacteria in our environment, to describe clinical manifestations of the disease and to point out the importance of its prevention. All patients had epidemiological evidence of being in contact with pork meat. There were no data about diseased pigs. The estimated incubation period was 4 to 8 days. All patients had meningeal signs. Clinical symptoms included shivering, fever, vomiting, headache, malaise, vertigo and tinitus. Three patients presented with alerterd level of awarrness. Four patients developed very severe bilateral hearing impairment, whereas one endophtalmtis and one developed endocarditis. The cerebrospinal fluid (CSF) was opalescent in four patients, and only one patient presented with clear CSF. CSF examination showed typical changes characteristic for bacterial meningitis. Streptoccocus suis was isolated in CSF in all patients, and in one patient the bacteria was isolated in blood as well. All patients underwent treatement with II and III generation cephalosporins and one with one

  14. Proteome analysis identifies the Dpr protein of Streptococcus mutans as an important factor in the presence of early streptococcal colonizers of tooth surfaces.

    Directory of Open Access Journals (Sweden)

    Akihiro Yoshida

    Full Text Available Oral streptococci are primary colonizers of tooth surfaces and Streptococcus mutans is the principal causative agent of dental caries in humans. A number of proteins are involved in the formation of monospecies biofilms by S. mutans. This study analyzed the protein expression profiles of S. mutans biofilms formed in the presence or absence of S. gordonii, a pioneer colonizer of the tooth surface, by two-dimensional gel electrophoresis (2-DE. After identifying S. mutans proteins by Mass spectrometric analysis, their expression in the presence of S. gordonii was analyzed. S. mutans was inoculated with or without S. gordonii DL1. The two species were compartmentalized using 0.2-μl Anopore membranes. The biofilms on polystyrene plates were harvested, and the solubilized proteins were separated by 2-DE. When S. mutans biofilms were formed in the presence of S. gordonii, the peroxide resistance protein Dpr of the former showed 4.3-fold increased expression compared to biofilms that developed in the absence of the pioneer colonizer. In addition, we performed a competition assay using S. mutans antioxidant protein mutants together with S. gordonii and other initial colonizers. Growth of the dpr-knockout S. mutans mutant was significantly inhibited by S. gordonii, as well as by S. sanguinis. Furthermore, a cell viability assay revealed that the viability of the dpr-defective mutant was significantly attenuated compared to the wild-type strain when co-cultured with S. gordonii. Therefore, these results suggest that Dpr might be one of the essential proteins for S. mutans survival on teeth in the presence of early colonizing oral streptococci.

  15. Proteome Analysis Identifies the Dpr Protein of Streptococcus mutans as an Important Factor in the Presence of Early Streptococcal Colonizers of Tooth Surfaces

    Science.gov (United States)

    Yoshida, Akihiro; Niki, Mamiko; Yamamoto, Yuji; Yasunaga, Ai; Ansai, Toshihiro

    2015-01-01

    Oral streptococci are primary colonizers of tooth surfaces and Streptococcus mutans is the principal causative agent of dental caries in humans. A number of proteins are involved in the formation of monospecies biofilms by S. mutans. This study analyzed the protein expression profiles of S. mutans biofilms formed in the presence or absence of S. gordonii, a pioneer colonizer of the tooth surface, by two-dimensional gel electrophoresis (2-DE). After identifying S. mutans proteins by Mass spectrometric analysis, their expression in the presence of S. gordonii was analyzed. S. mutans was inoculated with or without S. gordonii DL1. The two species were compartmentalized using 0.2-μl Anopore membranes. The biofilms on polystyrene plates were harvested, and the solubilized proteins were separated by 2-DE. When S. mutans biofilms were formed in the presence of S. gordonii, the peroxide resistance protein Dpr of the former showed 4.3-fold increased expression compared to biofilms that developed in the absence of the pioneer colonizer. In addition, we performed a competition assay using S. mutans antioxidant protein mutants together with S. gordonii and other initial colonizers. Growth of the dpr-knockout S. mutans mutant was significantly inhibited by S. gordonii, as well as by S. sanguinis. Furthermore, a cell viability assay revealed that the viability of the dpr-defective mutant was significantly attenuated compared to the wild-type strain when co-cultured with S. gordonii. Therefore, these results suggest that Dpr might be one of the essential proteins for S. mutans survival on teeth in the presence of early colonizing oral streptococci. PMID:25816242

  16. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry identification of large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G

    DEFF Research Database (Denmark)

    Salgård Jensen, Christian; Dam-Nielsen, Casper; Arpi, Magnus

    2015-01-01

    BACKGROUND: The aim of this study was to investigate whether large colony beta-hemolytic streptococci containing Lancefield groups A, C, and G can be adequately identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-ToF). Previous studies show varying...

  17. Estimation of DMFT, Salivary Streptococcus Mutans Count, Flow Rate, Ph, and Salivary Total Calcium Content in Pregnant and Non-Pregnant Women: A Prospective Study.

    Science.gov (United States)

    Kamate, Wasim Ismail; Vibhute, Nupura Aniket; Baad, Rajendra Krishna

    2017-04-01

    Pregnancy, a period from conception till birth, causes changes in the functioning of the human body as a whole and specifically in the oral cavity that may favour the emergence of dental caries. Many studies have shown pregnant women at increased risk for dental caries, however, specific salivary caries risk factors and the particular period of pregnancy at heightened risk for dental caries are yet to be explored and give a scope of further research in this area. The aim of the present study was to assess the severity of dental caries in pregnant women compared to non-pregnant women by evaluating parameters like Decayed, Missing, Filled Teeth (DMFT) index, salivary Streptococcus mutans count, flow rate, pH and total calcium content. A total of 50 first time pregnant women in the first trimester were followed during their second trimester, third trimester and postpartum period for the evaluation of DMFT by World Health Organization (WHO) scoring criteria, salivary flow rate by drooling method, salivary pH by pH meter, salivary total calcium content by bioassay test kit and salivary Streptococcus mutans count by semiautomatic counting of colonies grown on Mitis Salivarius (MS) agar supplemented by 0.2U/ml of bacitracin and 10% sucrose. The observations of pregnant women were then compared with same parameters evaluated in the 50 non-pregnant women. Paired t-test and Wilcoxon sign rank test were performed to assess the association between the study parameters. Evaluation of different caries risk factors between pregnant and non-pregnant women clearly showed that pregnant women were at a higher risk for dental caries. Comparison of caries risk parameters during the three trimesters and postpartum period showed that the salivary Streptococcus mutans count had significantly increased in the second trimester , third trimester and postpartum period while the mean pH and mean salivary total calcium content decreased in the third trimester and postpartum period. These

  18. Estimation of DMFT, Salivary Streptococcus Mutans Count, Flow Rate, Ph, and Salivary Total Calcium Content in Pregnant and Non-Pregnant Women: A Prospective Study

    Science.gov (United States)

    Vibhute, Nupura Aniket; Baad, Rajendra Krishna

    2017-01-01

    Introduction Pregnancy, a period from conception till birth, causes changes in the functioning of the human body as a whole and specifically in the oral cavity that may favour the emergence of dental caries. Many studies have shown pregnant women at increased risk for dental caries, however, specific salivary caries risk factors and the particular period of pregnancy at heightened risk for dental caries are yet to be explored and give a scope of further research in this area. Aim The aim of the present study was to assess the severity of dental caries in pregnant women compared to non-pregnant women by evaluating parameters like Decayed, Missing, Filled Teeth (DMFT) index, salivary Streptococcus mutans count, flow rate, pH and total calcium content. Materials and Methods A total of 50 first time pregnant women in the first trimester were followed during their second trimester, third trimester and postpartum period for the evaluation of DMFT by World Health Organization (WHO) scoring criteria, salivary flow rate by drooling method, salivary pH by pH meter, salivary total calcium content by bioassay test kit and salivary Streptococcus mutans count by semiautomatic counting of colonies grown on Mitis Salivarius (MS) agar supplemented by 0.2U/ml of bacitracin and 10% sucrose. The observations of pregnant women were then compared with same parameters evaluated in the 50 non-pregnant women. Paired t-test and Wilcoxon sign rank test were performed to assess the association between the study parameters. Results Evaluation of different caries risk factors between pregnant and non-pregnant women clearly showed that pregnant women were at a higher risk for dental caries. Comparison of caries risk parameters during the three trimesters and postpartum period showed that the salivary Streptococcus mutans count had significantly increased in the second trimester, third trimester and postpartum period while the mean pH and mean salivary total calcium content decreased in the third

  19. Control of Glycolysis by Glyceraldehyde-3-Phosphate Dehydrogenase in Streptococcus cremoris and Streptococcus lactis

    NARCIS (Netherlands)

    POOLMAN, B; BOSMAN, B; KONINGS, WN

    1987-01-01

    The decreased response of the energy metabolism of lactose-starved Streptococcus cremoris upon readdition of lactose is caused by a decrease of the glycolytic activity. The decrease in glycolysis is accompanied by a decrease in the activities of glyceraldehyde-3-phosphate dehydrogenase and

  20. Antimicrobial activity of vanadium chloroperoxidase on planktonic Streptococcus mutans cells and Streptococcus mutans biofilms

    NARCIS (Netherlands)

    Hoogenkamp, M.A.; Crielaard, W.; ten Cate, J.M.; Wever, R.; Hartog, A.F.; Renirie, R.

    2009-01-01

    The aim of this study was to investigate the antimicrobial activity of vanadium chloroperoxidase (VCPO) reaction products on planktonic and biofilm cellsof Streptococcus mutans C180-2. Planktonic and biofilm cells were incubated in a buffered reaction mixture containing VCPO, halide (either chloride

  1. Influence of pH on inhibition of Streptococcus mutans by Streptococcus oligofermentans.

    Science.gov (United States)

    Liu, Ying; Chu, Lei; Wu, Fei; Guo, Lili; Li, Mengci; Wang, Yinghui; Wu, Ligeng

    2014-02-01

    Streptococcus oligofermentans is a novel strain of oral streptococcus that can specifically inhibit the growth of Streptococcus mutans. The aims of this study were to assess the growth of S. oligofermentans and the ability of S. oligofermentans to inhibit growth of Streptococcus mutans at different pH values. Growth inhibition was investigated in vitro using an interspecies competition assay. The 4-aminoantipyine method was used to measure the initial production rate and the total yield of hydrogen peroxide in S. oligofermentans. S. oligofermentans grew best at pH 7.0 and showed the most pronounced inhibitory effect when it was inoculated earlier than S. mutans. In terms of the total yield and the initial production rate of hydrogen peroxide by S. oligofermentans, the effects of the different culture pH values were as follows: pH 7.0 > 6.5 > 6.0 > 7.5 > 5.5 = 8.0 (i.e. there was no significant difference between pH 5.5 and pH 8.0). Environmental pH and the sequence of inoculation significantly affected the ability of S. oligofermentans to inhibit the growth of S. mutans. The degree of inhibition may be attributed to the amount of hydrogen peroxide produced. © 2013 Eur J Oral Sci.

  2. Spring forward with improved Nile tilapia Oreochromis niloticus resistant to Streptococcus iniae and Streptococcus agalactiae IB

    Science.gov (United States)

    Tilapia aquaculture worldwide is valued around US $ 7 billion. Tilapia are an important source of protein for domestic (top 5 most consumed seafoods) and global food security. Two gram postitive bacteria, Streptococcus iniae and S. agalactiae, are responsible for billion dollar losses annually. Gen...

  3. Efficacy of some synthetic antibiotics on Streptococcus pneumoniae ...

    African Journals Online (AJOL)

    Effects of some synthetic antibiotics on Streptococcus pnemoniae and Proteus mirabilis isolated from cultured Clarias gariepinus, an important food fish raised in a concrete tank was carried out to ascertain their remedies on mortalities of the Clarias gariepinus adult fish. Streptococcus pnemoniae and Proteus mirabilis were ...

  4. Streptococcus suis meningitis can require a prolonged treatment course

    Directory of Open Access Journals (Sweden)

    Jean Dejace

    2017-12-01

    Full Text Available We report a case of recrudescent Streptococcus suis meningitis requiring a prolonged treatment course. A few similar cases can be found in the burgeoning literature on what remains a relatively uncommon disease in humans, and these patients should be monitored carefully upon completion of therapy. Keywords: Meningitis, Relapse, Duration, Streptococcus suis

  5. Endocarditis caused by Streptococcus canis: an emerging zoonosis?

    Science.gov (United States)

    Lacave, Guillaume; Coutard, Aymeric; Troché, Gilles; Augusto, Sandrine; Pons, Stéphanie; Zuber, Benjamin; Laurent, Virginie; Amara, Marlène; Couzon, Brigitte; Bédos, Jean-Pierre; Pangon, Béatrice; Grimaldi, David

    2016-02-01

    We report a human case of infective endocarditis caused by Streptococcus canis. Identification was carried out from positive blood culture using mass spectrometry and SodA gene sequencing. S. canis related zoonotic invasive infections may have been previously underdiagnosed due to inadequate identification of group G Streptococcus species.

  6. Diversity of human small intestinal Streptococcus and Veillonella populations.

    Science.gov (United States)

    van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J; Zoetendal, Erwin G; Kleerebezem, Michiel

    2013-08-01

    Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed abundant populations of Streptococcus spp. most affiliated with S. salivarius, S. thermophilus, and S. parasanguinis, as well as Veillonella spp. affiliated with V. atypica, V. parvula, V. dispar, and V. rogosae. Relative abundances varied per subject and time of sampling. Streptococcus and Veillonella isolates were cultured using selective media from ileostoma effluent samples collected at two time points from a single subject. The richness of the Streptococcus and Veillonella isolates was assessed at species and strain level by 16S rRNA gene sequencing and genetic fingerprinting, respectively. A total of 160 Streptococcus and 37 Veillonella isolates were obtained. Genetic fingerprinting differentiated seven Streptococcus lineages from ileostoma effluent, illustrating the strain richness within this ecosystem. The Veillonella isolates were represented by a single phylotype. Our study demonstrated that the small intestinal Streptococcus populations displayed considerable changes over time at the genetic lineage level because only representative strains of a single Streptococcus lineage could be cultivated from ileostoma effluent at both time points. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  7. Correlates of vaginal colonization with group B streptococci among pregnant women

    Directory of Open Access Journals (Sweden)

    Tsering Chomu Dechen

    2010-01-01

    Full Text Available Background: A study of genital colonization by group B streptococcus (GBS was conducted in pregnant women in their third trimester, which is a known risk factor of morbidity and mortality among newborns. Aims: The present study was undertaken to study the prevalence and the correlates of vaginal colonization by GBS among pregnant women. Setting and Design: This observational cross-sectional study was conducted during September 2002 to March 2004 on 524 pregnant women. Materials and Methods: Three high vaginal swabs were obtained from all the pregnant women admitted at term and in preterm labor. Two swabs were used for aerobic culture and the third one for gram staining. The first set of swabs was cultured on 5% Sheep blood agar plates. The second set of swabs were inoculated into Todd-Hewitt broth and then subcultured in 5% Sheep blood agar plates. The main outcome measures were the presence of GBS infection in comparison to the age group, gravida, gestational age, premature rupture of membrane (PROM, preterm labor and association with febrile spells of the present pregnancy. Results: The culture positivity rate of GBS was 4.77% and coexistent organisms isolated were Candida species (36%, Staphylococcus aureus (8% and Enterococcus species (8%. Culture positivity in the age group of 18-25 years was 5.71%, of which 5.74% were in their first pregnancy. The correlation between age group and gravida with GBS culture positivity was statistically insignificant. The culture positivity in <36 weeks of gestational age was 6.93%. This relation was statistically significant. Twenty-eight percent developed PROM. Sixty-four percent of culture positives had preterm labor. Conclusion: GBS infection among pregnant women was significantly correlated with the gestational age, PROM and preterm labor. In pregnancy GBS colonization causes asymptomatic bacteriuria or UTI. It is a well known cause of puerperal infections with amnionitis,endometritis and sepsis being

  8. Radiocomplexation and biological evaluation of nemonoxacin in mice infected with multiresistant Staphylococcus aureus and penicillin-resistant Streptococci

    International Nuclear Information System (INIS)

    El-Kawy, O.A.; Farah, K.

    2015-01-01

    In the current investigation nemonoxacin (NMX) was radiolabeled with 99m Tc in the presence of stannous chloride dihydrate as reducing agent. Factors affecting the percent labeling yield of 99m Tc-Nemonoxacin ( 99m Tc-NMX) complex were studied in details. The labeled compound was radiochemically characterized and was stable for a time up to 4 h. The complex showed in vitro saturated binding with living multiresistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococci (PRSC). Biodistribution and imaging studies were performed. All results showed that 99m Tc-NMX complex is a promising agent for MRSA and PRSC infection imaging and can differentiate between infected and sterile inflammations. (author)

  9. Specialized adaptation of a lactic acid bacterium to the milk environment: the comparative genomics of Streptococcus thermophilus LMD-9

    Directory of Open Access Journals (Sweden)

    Altermann Eric

    2011-08-01

    Full Text Available Abstract Background Streptococcus thermophilus represents the only species among the streptococci that has “Generally Regarded As Safe” status and that plays an economically important role in the fermentation of yogurt and cheeses. We conducted comparative genome analysis of S. thermophilus LMD-9 to identify unique gene features as well as features that contribute to its adaptation to the dairy environment. In addition, we investigated the transcriptome response of LMD-9 during growth in milk in the presence of Lactobacillus delbrueckii ssp. bulgaricus, a companion culture in yogurt fermentation, and during lytic bacteriophage infection. Results The S. thermophilus LMD-9 genome is comprised of a 1.8 Mbp circular chromosome (39.1% GC; 1,834 predicted open reading frames and two small cryptic plasmids. Genome comparison with the previously sequenced LMG 18311 and CNRZ1066 strains revealed 114 kb of LMD-9 specific chromosomal region, including genes that encode for histidine biosynthetic pathway, a cell surface proteinase, various host defense mechanisms and a phage remnant. Interestingly, also unique to LMD-9 are genes encoding for a putative mucus-binding protein, a peptide transporter, and exopolysaccharide biosynthetic proteins that have close orthologs in human intestinal microorganisms. LMD-9 harbors a large number of pseudogenes (13% of ORFeome, indicating that like LMG 18311 and CNRZ1066, LMD-9 has also undergone major reductive evolution, with the loss of carbohydrate metabolic genes and virulence genes found in their streptococcal counterparts. Functional genome distribution analysis of ORFeomes among streptococci showed that all three S. thermophilus strains formed a distinct functional cluster, further establishing their specialized adaptation to the nutrient-rich milk niche. An upregulation of CRISPR1 expression in LMD-9 during lytic bacteriophage DT1 infection suggests its protective role against phage invasion. When co

  10. Specialized adaptation of a lactic acid bacterium to the milk environment: the comparative genomics of Streptococcus thermophilus LMD-9.

    Science.gov (United States)

    Goh, Yong Jun; Goin, Caitlin; O'Flaherty, Sarah; Altermann, Eric; Hutkins, Robert

    2011-08-30

    Streptococcus thermophilus represents the only species among the streptococci that has "Generally Regarded As Safe" status and that plays an economically important role in the fermentation of yogurt and cheeses. We conducted comparative genome analysis of S. thermophilus LMD-9 to identify unique gene features as well as features that contribute to its adaptation to the dairy environment. In addition, we investigated the transcriptome response of LMD-9 during growth in milk in the presence of Lactobacillus delbrueckii ssp. bulgaricus, a companion culture in yogurt fermentation, and during lytic bacteriophage infection. The S. thermophilus LMD-9 genome is comprised of a 1.8 Mbp circular chromosome (39.1% GC; 1,834 predicted open reading frames) and two small cryptic plasmids. Genome comparison with the previously sequenced LMG 18311 and CNRZ1066 strains revealed 114 kb of LMD-9 specific chromosomal region, including genes that encode for histidine biosynthetic pathway, a cell surface proteinase, various host defense mechanisms and a phage remnant. Interestingly, also unique to LMD-9 are genes encoding for a putative mucus-binding protein, a peptide transporter, and exopolysaccharide biosynthetic proteins that have close orthologs in human intestinal microorganisms. LMD-9 harbors a large number of pseudogenes (13% of ORFeome), indicating that like LMG 18311 and CNRZ1066, LMD-9 has also undergone major reductive evolution, with the loss of carbohydrate metabolic genes and virulence genes found in their streptococcal counterparts. Functional genome distribution analysis of ORFeomes among streptococci showed that all three S. thermophilus strains formed a distinct functional cluster, further establishing their specialized adaptation to the nutrient-rich milk niche. An upregulation of CRISPR1 expression in LMD-9 during lytic bacteriophage DT1 infection suggests its protective role against phage invasion. When co-cultured with L. bulgaricus, LMD-9 overexpressed genes

  11. Effect of Periodontal Therapy With Amoxicillin-Metronidazole on Pharyngeal Carriage of Penicillin- and Erythromycin-Resistant Viridans Streptococci.

    Science.gov (United States)

    Mombelli, Andrea; Cionca, Norbert; Almaghlouth, Adnan; Cherkaoui, Abdessalam; Schrenzel, Jacques; Giannopoulou, Catherine

    2016-05-01

    Previous studies have focused on antibiotic resistance of Gram-negative bacteria before and after periodontal therapy. The purpose of this analysis is to assess changes in resistance patterns of the commensal Gram-positive microbiota. The viridans group streptococci (VGS) have been suggested to serve as reservoirs of resistance genes for more pathogenic streptococci and may be implicated in some non-oral infections. In this randomized clinical trial, 80 patients with periodontitis are distributed randomly into two groups. In group A, patients received 375 mg amoxicillin and 500 mg metronidazole three times per day for 7 days during the non-surgical treatment phase (T1). In group B, the antibiotics were administered during the surgical phase (T2). Resistance of VGS to penicillin and erythromycin was determined by the epsilometer test. At baseline, VGS from 12.5% (group A) and 11.8% (group B) of patients had a minimum inhibitory concentration (MIC) >2 μg/mL to penicillin. Three months after T1, VGS from 15.6% and 16.7% of patients had an MIC >2 μg/mL, respectively. Six months after T2 VGS from 5.9% and 5.9% and 12 months after T2 VGS from 6.1% and 6.3% patients had an MIC >2 μg/mL. There was no effect of therapy with antibiotics, administered either in T1 or T2, on the carriage of penicillin-resistant VGS. Erythromycin resistance was high at baseline and remained unchanged throughout the study. MICs for penicillin and erythromycin were correlated (P penicillin or erythromycin.

  12. An investigation on drug resistance of viridance group streptococci isolated from 3-12 years healthy individuals

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    Abasalt Borji

    2010-11-01

    Full Text Available Background: Nowadays, dental and oral infections are regarded as major threats to human health whose treatments are always prime concern of dental surgeons. Staphylococci, streptococci, actinomycetes and mycoplasma are the most common causative agents of such infections.The objective of this study was to investigate drug resistance of viridance group streptococci (VGS isolated from healthy children between 3-12 years old versus common antibiotics utilized in dentistry. The findings of this study can help dentists using the antibiotic of choice in remedial practices as well as assessment of sensitivity or resistance of VGS.Materials and Method: In this cross sectional study saliva samples from of 213 healthy children aged between 3-12 years from their buccal surface of posterior teeth were collected and after culture. species were isolated. Next, drug sensitivity test was carried out by disc diffusion technique to find out sensitivity or resistance of VGS to penicillin, erythromycin, vancomycin, clindamycin, cephotaxim and cephteriaxon.Result: Our findings revealed that resistance of VGS to antibiotics including: clindamycin, penicillin, cephteriaxon, erythromycin, vancomycin and cephotaxim was 59.6%, 52.6%, 30.5%, 12.2%, 10.8% and 1.5% and sensitivity of VGS to such antibiotics was 19.7%, 29.6%, 23%, 13.4%, 4.5% and 29.6% respectively.Conclusion: The results showed widespread resistance of VGS against chosen antibiotics, this indicates considerable use of antibiotics in this region.Controlled use and prescription of different antibiotics as well as increasing people knowledge about misuse of antibiotics in order to decrease the drug resistance is important

  13. Necrotizing fasciitis caused by group A streptococcus

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    Mikić Dragan

    2002-01-01

    Full Text Available The first case of the confirmed necrotizing fasciitis caused by Group A Streptococcus in Yugoslavia was presented. Male patient, aged 28, in good health, suddenly developed symptoms and signs of severe infective syndrome and intensive pain in the axillary region. Parenteral antibiotic, substitution and supportive therapy was conducted along with the radical surgical excision of the necrotizing tissue. The patient did not develop streptococcal toxic shock syndrome thanks to the early established diagnosis and timely applied aggressive treatment. He was released from the hospital as completely cured two months after the admission.

  14. Streptococcus anginosus infections: crossing tissue planes.

    Science.gov (United States)

    Sunwoo, Bernie Y; Miller, Wallace T

    2014-10-01

    Streptococcus anginosus has long been recognized to cause invasive pyogenic infections. This holds true for thoracic infections where S. anginosus has a propensity for abscess and empyema formation. Early diagnosis is important given the significant morbidity and mortality associated with thoracic S. anginosus infections. Yet, distinguishing thoracic S. anginosus clinically is difficult. We present three cases of thoracic S. anginosus that demonstrated radiographic extension across tissue planes, including the interlobar fissure, diaphragm, and chest wall. Few infectious etiologies are known to cross tissue planes. Accordingly, we propose S. anginosus be considered among the differential diagnosis of potential infectious etiologies causing radiographic extension across tissue planes.

  15. Phylogenetic relationship and virulence inference of Streptococcus Anginosus Group: curated annotation and whole-genome comparative analysis support distinct species designation

    Science.gov (United States)

    2013-01-01

    Background The Streptococcus Anginosus Group (SAG) represents three closely related species of the viridans group streptococci recognized as commensal bacteria of the oral, gastrointestinal and urogenital tracts. The SAG also cause severe invasive infections, and are pathogens during cystic fibrosis (CF) pulmonary exacerbation. Little genomic information or description of virulence mechanisms is currently available for SAG. We conducted intra and inter species whole-genome comparative analyses with 59 publically available Streptococcus genomes and seven in-house closed high quality finished SAG genomes; S. constellatus (3), S. intermedius (2), and S. anginosus (2). For each SAG species, we sequenced at least one numerically dominant strain from CF airways recovered during acute exacerbation and an invasive, non-lung isolate. We also evaluated microevolution that occurred within two isolates that were cultured from one individual one year apart. Results The SAG genomes were most closely related to S. gordonii and S. sanguinis, based on shared orthologs and harbor a similar number of proteins within each COG category as other Streptococcus species. Numerous characterized streptococcus virulence factor homologs were identified within the SAG genomes including; adherence, invasion, spreading factors, LPxTG cell wall proteins, and two component histidine kinases known to be involved in virulence gene regulation. Mobile elements, primarily integrative conjugative elements and bacteriophage, account for greater than 10% of the SAG genomes. S. anginosus was the most variable species sequenced in this study, yielding both the smallest and the largest SAG genomes containing multiple genomic rearrangements, insertions and deletions. In contrast, within the S. constellatus and S. intermedius species, there was extensive continuous synteny, with only slight differences in genome size between strains. Within S. constellatus we were able to determine important SNPs and changes in

  16. Group B Streptococcus and the Vaginal Microbiota.

    Science.gov (United States)

    Rosen, Geoffrey H; Randis, Tara M; Desai, Purnahamsi V; Sapra, Katherine J; Ma, Bing; Gajer, Pawel; Humphrys, Michael S; Ravel, Jacques; Gelber, Shari E; Ratner, Adam J

    2017-09-15

    Streptococcus agalactiae (group B Streptococcus [GBS]) is an important neonatal pathogen and emerging cause of disease in adults. The major risk factor for neonatal disease is maternal vaginal colonization. However, little is known about the relationship between GBS and vaginal microbiota. Vaginal lavage samples from nonpregnant women were tested for GBS, and amplicon-based sequencing targeting the 16S ribosomal RNA V3-V4 region was performed. Four hundred twenty-eight of 432 samples met the high-quality read threshold. There was no relationship between GBS carriage and demographic characteristics, α-diversity, or overall vaginal microbiota community state type (CST). Within the non-Lactobacillus-dominant CST IV, GBS positive status was significantly more prevalent in CST IV-A than CST IV-B. Significant clustering by GBS status was noted on principal coordinates analysis, and 18 individual taxa were found to be significantly associated with GBS carriage by linear discriminant analysis. After adjusting for race/ethnicity, 4 taxa were positively associated with GBS, and 6 were negatively associated. Vaginal microbiota CST and α-diversity are not related to GBS status. However, specific microbial taxa are associated with colonization of this important human pathogen, highlighting a potential role for the microbiota in promotion or inhibition of GBS colonization. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  17. A new endemic representative of the genus Rascioduvalius S. B. Ćurčić, Brajković, Mitić & B. P. M. Ćurčić from Mt. Zlatibor, Western Serbia (Trechini, Carabidae, Coleoptera

    Directory of Open Access Journals (Sweden)

    Ćurčić Srećko B.

    2005-01-01

    Full Text Available A new species of cavernicolous and endemic trechine ground beetles Rascioduvalis zlatiborensis n. sp., is described and diagnosed in the present paper. Also, all important taxonomic features are considered and illustrated. The type specimens of the new species were collected from the Markova (= Ršumska Pećina Cave, village of Gornji Ljubiš, Mt. Zlatibor, Western Serbia. The new species and its congeners belong to a separate phyletic lineage of Tertiary age. All members of Rascioduvalius S. B. Ćurčić, Brajković, Mitić & B. P. M. Ćurčić are distributed in Western Serbia only, where they have gone through intense differentiation and radiation due to evolution of the karstic relief.

  18. Use of partial budgeting to determine the economic benefits of antibiotic treatment of chronic subclinical mastitis caused by Streptococcus uberis or Streptococcus dysgalactiae

    NARCIS (Netherlands)

    Swinkels, J.M.; Rooijendijk, J.G.A.; Zadoks, R.N.; Hogeveen, H.

    2005-01-01

    The economic effect of lactational antibiotic treatment of chronic subclinical intramammary infections due to Streptococcus uberis or Streptococcus dysgalactiae was explored by means of partial budgeting. Effects at cow level and herd level were modelled, including prevention of clinical mastitis

  19. Reappraisal of the taxonomy of Streptococcus suis serotypes 20, 22 and 26: Streptococcus parasuis sp. nov.

    Science.gov (United States)

    Nomoto, R; Maruyama, F; Ishida, S; Tohya, M; Sekizaki, T; Osawa, Ro

    2015-02-01

    In order to clarify the taxonomic position of serotypes 20, 22 and 26 of Streptococcus suis, biochemical and molecular genetic studies were performed on isolates (SUT-7, SUT-286(T), SUT-319, SUT-328 and SUT-380) reacted with specific antisera of serotypes 20, 22 or 26 from the saliva of healthy pigs as well as reference strains of serotypes 20, 22 and 26. Comparative recN gene sequencing showed high genetic relatedness among our isolates, but marked differences from the type strain S. suis NCTC 10234(T), i.e. 74.8-75.7 % sequence similarity. The genomic relatedness between the isolates and other strains of species of the genus Streptococcus, including S. suis, was calculated using the average nucleotide identity values of whole genome sequences, which indicated that serotypes 20, 22 and 26 should be removed taxonomically from S. suis and treated as a novel genomic species. Comparative sequence analysis revealed 99.0-100 % sequence similarities for the 16S rRNA genes between the reference strains of serotypes 20, 22 and 26, and our isolates. Isolate STU-286(T) had relatively high 16S rRNA gene sequence similarity with S. suis NCTC 10234(T) (98.8 %). SUT-286(T) could be distinguished from S. suis and other closely related species of the genus Streptococcus using biochemical tests. Due to its phylogenetic and phenotypic similarities to S. suis we propose naming the novel species Streptococcus parasuis sp. nov., with SUT-286(T) ( = JCM 30273(T) = DSM 29126(T)) as the type strain. © 2015 IUMS.

  20. Persistence of the oral probiotic Streptococcus salivarius M18 is dose dependent and megaplasmid transfer can augment their bacteriocin production and adhesion characteristics.

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    Jeremy P Burton

    Full Text Available Bacteriocin-producing probiotic Streptococcus salivarius M18 offers beneficial modulatory capabilities within the oral microbiome, apparently through potent inhibitory activity against potentially deleterious bacteria, such as Streptococcus pyogenes. The oral cavity persistence of S. salivarius M18 was investigated in 75 subjects receiving four different doses for 28 days. Sixty per cent of the subjects already had some inhibitor-producing S. salivarius in their saliva prior to probiotic intervention. Strain M18's persistence was dependent upon the dose, but not the period of administration. Culture analysis indicated that in some individuals the introduced strain had almost entirely replaced the indigenous S. salivarius, though the total numbers of the species did not increase. Selected subjects showing either high or low probiotic persistence had their salivary populations profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Analysis indicated that while certain bacterial phenotypes were markedly modulated, the overall composition of the oral microbiome was not modified by the probiotic treatment. Megaplasmids encoding bacteriocins and adhesion factors were transferred in vitro to generate a transconjugant S. salivarius exhibiting enhanced antimicrobial production and binding capabilities to HEp-2 cells. Since no widespread perturbation of the existing indigenous microbiota was associated with oral instillation and given its antimicrobial activity against potentially pathogenic streptococci, it appears that application of probiotic strain M18 offers potential low impact alternative to classical antibiotic prophylaxis. For candidate probiotic strains having relatively poor antimicrobial or adhesive properties, unique derivatives displaying improved probiotic performance may be engineered in vitro by megaplasmid transfer.

  1. Persistence of the oral probiotic Streptococcus salivarius M18 is dose dependent and megaplasmid transfer can augment their bacteriocin production and adhesion characteristics.

    Science.gov (United States)

    Burton, Jeremy P; Wescombe, Philip A; Macklaim, Jean M; Chai, Melissa H C; Macdonald, Kyle; Hale, John D F; Tagg, John; Reid, Gregor; Gloor, Gregory B; Cadieux, Peter A

    2013-01-01

    Bacteriocin-producing probiotic Streptococcus salivarius M18 offers beneficial modulatory capabilities within the oral microbiome, apparently through potent inhibitory activity against potentially deleterious bacteria, such as Streptococcus pyogenes. The oral cavity persistence of S. salivarius M18 was investigated in 75 subjects receiving four different doses for 28 days. Sixty per cent of the subjects already had some inhibitor-producing S. salivarius in their saliva prior to probiotic intervention. Strain M18's persistence was dependent upon the dose, but not the period of administration. Culture analysis indicated that in some individuals the introduced strain had almost entirely replaced the indigenous S. salivarius, though the total numbers of the species did not increase. Selected subjects showing either high or low probiotic persistence had their salivary populations profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Analysis indicated that while certain bacterial phenotypes were markedly modulated, the overall composition of the oral microbiome was not modified by the probiotic treatment. Megaplasmids encoding bacteriocins and adhesion factors were transferred in vitro to generate a transconjugant S. salivarius exhibiting enhanced antimicrobial production and binding capabilities to HEp-2 cells. Since no widespread perturbation of the existing indigenous microbiota was associated with oral instillation and given its antimicrobial activity against potentially pathogenic streptococci, it appears that application of probiotic strain M18 offers potential low impact alternative to classical antibiotic prophylaxis. For candidate probiotic strains having relatively poor antimicrobial or adhesive properties, unique derivatives displaying improved probiotic performance may be engineered in vitro by megaplasmid transfer.

  2. In vitro characterization of PlySK1249, a novel phage lysin, and assessment of its antibacterial activity in a mouse model of Streptococcus agalactiae bacteremia.

    Science.gov (United States)

    Oechslin, Frank; Daraspe, Jean; Giddey, Marlyse; Moreillon, Philippe; Resch, Grégory

    2013-12-01

    Beta-hemolytic Streptococcus agalactiae is the leading cause of bacteremia and invasive infections. These diseases are treated with β-lactams or macrolides, but the emergence of less susceptible and even fully resistant strains is a cause for concern. New bacteriophage lysins could be promising alternatives against such organisms. They hydrolyze the bacterial peptidoglycan at the end of the phage cycle, in order to release the phage progeny. By using a bioinformatic approach to screen several beta-hemolytic streptococci, a gene coding for a lysin was identified on a prophage carried by Streptococcus dysgalactiae subsp. equisimilis SK1249. The gene product, named PlySK1249, harbored an original three-domain structure with a central cell wall-binding domain surrounded by an N-terminal amidase and a C-terminal CHAP domain. Purified PlySK1249 was highly lytic and bactericidal for S. dysgalactiae (2-log10 CFU/ml decrease within 15 min). Moreover, it also efficiently killed S. agalactiae (1.5-log10 CFU/ml decrease within 15 min) but not several streptococcal commensal species. We further investigated the activity of PlySK1249 in a mouse model of S. agalactiae bacteremia. Eighty percent of the animals (n = 10) challenged intraperitoneally with 10(6) CFU of S. agalactiae died within 72 h, whereas repeated injections of PlySK1249 (45 mg/kg 3 times within 24 h) significantly protected the mice (P S. dysgalactiae, demonstrated high cross-lytic activity against S. agalactiae both in vitro and in vivo. These encouraging results indicated that PlySK1249 might represent a good candidate to be developed as a new enzybiotic for the treatment of systemic S. agalactiae infections.

  3. Prevalence of Complement-Mediated Cell Lysis-like Gene (sicG) in Streptococcus dysgalactiae subsp. equisimilis Isolates From Japan (2014-2016).

    Science.gov (United States)

    Takahashi, Takashi; Fujita, Tomohiro; Shibayama, Akiyoshi; Tsuyuki, Yuzo; Yoshida, Haruno

    2017-07-01

    Streptococcus dysgalactiae subsp. equisimilis (SDSE; a β-hemolytic streptococcus of human or animal origin) infections are emerging worldwide. We evaluated the clonal distribution of complement-mediated cell lysis-like gene (sicG) among SDSE isolates from three central prefectures of Japan. Group G/C β-hemolytic streptococci were collected from three institutions from April 2014 to March 2016. Fifty-five strains (52 from humans and three from animals) were identified as SDSE on the basis of 16S rRNA sequencing data.; they were obtained from 25 sterile (blood, joint fluid, and cerebrospinal fluid) and 30 non-sterile (skin-, respiratory tract-, and genitourinary tract-origin) samples. emm genotyping, multilocus sequence typing, sicG amplification/sequencing, and random amplified polymorphic DNA (RAPD) analysis of sicG-positive strains were performed. sicG was detected in 30.9% of the isolates (16 human and one canine) and the genes from the 16 human samples (blood, 10; open pus, 3; sputum, 2; throat swab, 1) and one canine sample (open pus) showed the same sequence pattern. All sicG-harboring isolates belonged to clonal complex (CC) 17, and the most prevalent emm type was stG6792 (82.4%). There was a significant association between sicG presence and the development of skin/soft tissue infections. CC17 isolates with sicG could be divided into three subtypes by RAPD analysis. CC17 SDSE harboring sicG might have spread into three closely-related prefectures in central Japan during 2014-2016. Clonal analysis of isolates from other areas might be needed to monitor potentially virulent strains in humans and animals. © The Korean Society for Laboratory Medicine

  4. Bovine S protein (vitronectin increases phagocytosis of Streptococcus dysgalactiae Aumento na fagocitose de Streptococcus dysgalactiae pela ação da proteína S bovina (vitronectina

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    Laerte Francisco Filippsen

    1999-01-01

    Full Text Available The effects of bovine S protein (vitronectin on phagocytosis of Streptococcus dysgalactiae strains isolated from cattle with mastitis were investigated. Phagocytized streptococci were determined by a fluorometric microassay using glass adherent polymorphonuclear neutrophils (PMN. Preincubation of S. dysgalactiae with bovine S protein significantly increased their phagocytosis by PMN. Bovine S protein had no effect on phagocytic killing of non-S protein binding S. pyogenes cultures. Enzymatic digestion of the bovine S protein binding sites on S. dysgalactiae with pronase resulted in a significative reduction of the effects of S protein on phagocytosis. It could thus be concluded that in addition to its role as a promoter of cellular adhesion and complement inhibitor, bovine S protein may also influence the phagocytosis of S. dysgalactiae during inflammatory processes.Foram investigados os efeitos da proteína S bovina (vitronectina na fagocitose de amostras de Streptococcus dysgalactiae isoladas de bovinos com mastite. A determinação do número de estreptococos fagocitados foi realizada pelo método fluorométrico utilizando neutrófilos polimorfonucleares (NPM aderidos em lâminas de vidro. A pré-incubação do S. dysgalactiae com a proteína S bovina aumentou significativamente a sua fagocitose por NPM. A proteína S bovina não causou efeito na fagocitose de culturas de S. pyogenes, já que não apresentam sítios de ligação para esta proteína. A digestão enzimática com pronase dos sítios de ligação S. dysgalactiae para a proteína S bovina resultou numa significativa redução do efeito da proteína S na fagocitose. Pode-se concluir que além do papel como promotor da adesão celular e inibidor do complemento, a proteína S bovina pode também influir na fagocitose do S. dysgalactiae durante os processos inflamatórios.

  5. Current Taxonomical Situation of Streptococcus suis.

    Science.gov (United States)

    Okura, Masatoshi; Osaki, Makoto; Nomoto, Ryohei; Arai, Sakura; Osawa, Ro; Sekizaki, Tsutomu; Takamatsu, Daisuke

    2016-06-24

    Streptococcus suis, a major porcine pathogen and an important zoonotic agent, is considered to be composed of phenotypically and genetically diverse strains. However, recent studies reported several "S. suis-like strains" that were identified as S. suis by commonly used methods for the identification of this bacterium, but were regarded as distinct species from S. suis according to the standards of several taxonomic analyses. Furthermore, it has been suggested that some S. suis-like strains can be assigned to several novel species. In this review, we discuss the current taxonomical situation of S. suis with a focus on (1) the classification history of the taxon of S. suis; (2) S. suis-like strains revealed by taxonomic analyses; (3) methods for detecting and identifying this species, including a novel method that can distinguish S. suis isolates from S. suis-like strains; and (4) current topics on the reclassification of S. suis-like strains.

  6. Streptococcus pneumoniae, mecanismos de resistencia antimicrobiana

    Directory of Open Access Journals (Sweden)

    Amauri Noda Albelo

    2011-09-01

    Full Text Available El Streptococcus pneumoniae, principal agente causal de la neumonía comunitaria, líder en la etiología de la otitis media y la meningitis, en las últimas 3 décadas ha incrementado, de manera importante, su resistencia a los agentes terapéuticos más utilizados, como los betalactámicos, macrólidos, azálidos y fluroquinolonas. La versatilidad adaptativa del microorganismo le ha permitido crear mecanismos capaces de sobreponerse a cualquiera de estas agresiones terapéuticas con un grado variable de eficacia. Se realiza una revisión de los mecanismos más importantes implicados en la adquisición de resistencia antimicrobiana por S. pneumoniae, y se precisan algunos de los factores de riesgo implicados en infección por S. pneumoniae resistente.

  7. The homodimeric GBS1074 from Streptococcus agalactiae

    International Nuclear Information System (INIS)

    Shukla, Anshuman; Pallen, Mark; Anthony, Mark; White, Scott A.

    2010-01-01

    The homodimeric nature of the ESAT-6 homologue GBS1074 and the potential for fibre-like assemblies are revealed by the 2 Å resolution crystal structure. ESAT-6 is a well characterized secreted protein from Mycobacterium tuberculosis and represents the archetype of the WXG100 family of proteins. Genes encoding ESAT-6 homologues have been identified in the genome of the human pathogen Streptococcus agalactiae; one of these genes, esxA, has been cloned and the recombinant protein has been crystallized. In contrast to M. tuberculosis ESAT-6, the crystal structure of GBS1074 reveals a homodimeric structure similar to homologous structures from Staphylococcus aureus and Helicobacter pylori. Intriguingly, GBS1074 forms elongated fibre-like assemblies in the crystal structure

  8. Streptococcus pyogenes vulvovaginitis in children in Nottingham.

    Science.gov (United States)

    Donald, F. E.; Slack, R. C.; Colman, G.

    1991-01-01

    Isolates of Streptococcus pyogenes from vaginal swabs of children with vulvovaginitis received at Nottingham Public Health Laboratory during 1986-9 were studied. A total of 159 isolates was made during the 4 years, increasing from 17 in 1986 to 64 in 1989 and accounting for 11% of all vaginal swabs received from children. The numbers of throat swabs yielding S. pyogenes also showed an increase from 974 in 1986 to 1519 in 1989. A winter peak of isolates was noted for both vaginal swabs and throat swabs. A total of 98 strains from vaginal swabs were serotyped: 22 different types were identified, 61% of which were the common types M4, M6, R28 and M12. Erythromycin sensitivity was done on 89 strains; 84% were highly sensitive (MIC less than 0.03 mg/l). There are no other reports of such large numbers in the literature; the reason for seeing this increase in Nottingham is unclear. PMID:2050200

  9. Development of Streptococcus agalactiae vaccines for tilapia.

    Science.gov (United States)

    Liu, Guangjin; Zhu, Jielian; Chen, Kangming; Gao, Tingting; Yao, Huochun; Liu, Yongjie; Zhang, Wei; Lu, Chengping

    2016-12-21

    Vaccination is a widely accepted and effective method to prevent most pathogenic diseases in aquaculture. Various species of tilapia, especially Nile tilapia Oreochromis niloticus, are farmed worldwide because of their high consumer demand. Recently, the tilapia-breeding industry has been hampered by outbreaks of Streptococcus agalactiae infection, which cause high mortality and huge economic losses. Many researchers have attempted to develop effective S. agalactiae vaccines for tilapia. This review provides a summary of the different kinds of S. agalactiae vaccines for tilapia that have been developed recently. Among the various vaccine types, inactivated S. agalactiae vaccines showed superior protection efficiency when compared with live attenuated, recombinant and DNA vaccines. With respect to vaccination method, injecting the vaccine into tilapia provided the most effective immunoprotection. Freund's incomplete adjuvant appeared to be suitable for tilapia vaccines. Other factors, such as immunization duration and number, fish size and challenge dose, also influenced the vaccine efficacy.

  10. The carriage of potentially pathogenic β-haemolytic streptococci (β-HS in healthy adult inhabitants of Wielkopolska, Poland

    Directory of Open Access Journals (Sweden)

    Maciej Bura

    2016-09-01

    Full Text Available Background . Acute pharyngitis is a common disease in primary health care patients. Beta-hemolytic streptococci (β-HS are a frequent etiological agent, while swab culture from the throat and palatine tonsils is the gold standard for diagnosis. Objectives. The evaluation of the prevalence of potentially pathogenic β-HS carriage in young adult inhabitants of Wielkopolska. Material and methods. The study included 205 healthy young adult (18–44 years old (29.0 ± 6.4 inhabitants (M – 95, F – 110 of Wielkopolska (Poland. Two swabs were taken from the throat: the first one was used to perform a rapid antigenic diagnostic test (RAD T for group A streptococci (GAS and the second to grow a conventional culture. If β-HS grew, isolates were serotyped according to Lancefield. In addition, simple demographic and medical data were collected from the subjects. The study was financed from funds granted within the first edition of the “Give a hand” project (Karol Marcinkowski Poznan University of Medical Sciences. Results . Positive throat cultures were obtained in 15.6% out of 205 persons (n = 32. The distribution of β-HS serogroup results was as follows: group C (GCS – 17 cases (53.1% of cases where β-HS was positive, group F (GFS – 9 cases (28.1%, GAS – 3 people (9.4% and group G (GGS – 3 subjects (9.4%. The growth of the discussed bacteria in cultures was moderate or high in 53% of these cases. RAD T was positive in 5 cases (but only one person had GAS in throat culture. The positive culture result was significantly more frequent in men (62.5% out of 32 cases with β-HS growth, p = 0.0460. Conclusions . 1. The possibility of β-HS carriage must be taken into account when analysing the results of throat swab cultures. 2. GAS carriage is significantly lower than non-GAS carriage. 3. GCS were the most prevalent among non-GAS. 4. Being male may predispose individuals to β-HS carriage.

  11. Stimulation of protective antibodies against type Ia and Ib group B streptococci by a type Ia polysaccharide-tetanus toxoid conjugate vaccine.

    OpenAIRE

    Wessels, M R; Paoletti, L C; Rodewald, A K; Michon, F; DiFabio, J; Jennings, H J; Kasper, D L

    1993-01-01

    Antisera elicited by type Ia group B streptococci (GBS) contain antibodies that react with both type Ia and type Ib strains. Previous studies suggested that antibodies elicited by type Ia organisms recognized a carbohydrate antigen or epitope common to Ia and Ib strains. We now report the synthesis and immunogenicity testing of a type Ia polysaccharide-tetanus toxoid (Ia-TT) conjugate vaccine. Ia-TT elicited type Ia polysaccharide-specific immunoglobulin G antibodies in all three of the rabbi...

  12. Anti-Streptococcus pyogenes Activity of Selected Medicinal Plant ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research August 2013; 12 (4): 535-540. ISSN: 1596-5996 .... Table 1: Antibacterial activity of selected Thai medicinal plants against Streptococcus pyogenes NPRC 101. Botanical ..... Naphthoquinones,.

  13. The changing epidemiology of group B streptococcus bloodstream infection

    DEFF Research Database (Denmark)

    Ballard, Mark S; Schønheyder, Henrik C; Knudsen, Jenny Dahl

    2016-01-01

    Background Population-based studies conducted in single regions or countries have identified significant changes in the epidemiology of invasive group B streptococcus (GBS) infection. However, no studies have concurrently compared the epidemiology of GBS infections among multiple different region...

  14. Case Report of Necrotizing Fasciitis Associated with Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Lei Jiao

    2016-01-01

    Full Text Available Necrotizing fasciitis, caused by Streptococcus pneumoniae, is an extremely rare and life-threatening bacterial soft tissue infection. We report a case of early necrotizing fasciitis associated with Streptococcus pneumoniae infection in a 26-year-old man who was immunocompromised with mixed connective tissue disease. The patient presented with acute, painful, erythematous, and edematous skin lesions of his right lower back, which rapidly progressed to the right knee. The patient underwent surgical exploration, and a diagnosis of necrotizing fasciitis was confirmed by pathological evidence of necrosis of the fascia and neutrophil infiltration in tissue biopsies. Cultures of fascial tissue biopsies and blood samples were positive for Streptococcus pneumoniae. To our knowledge, this is the first report of necrotizing fasciitis resulting from Streptococcus pneumoniae diagnosed at early phase; the patient recovered well without surgical debridement.

  15. 21 CFR 866.3740 - Streptococcus spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3740 Streptococcus... derived from clinical specimens. The identification aids in the diagnosis of diseases caused by bacteria...

  16. The post-vaccine microevolution of invasive Streptococcus pneumoniae

    NARCIS (Netherlands)

    Cremers, Amelieke J H; Mobegi, Fredrick M; de Jonge, Marien I; van Hijum, Sacha A F T; Meis, Jacques F; Hermans, Peter W M; Ferwerda, Gerben; Bentley, Stephen D; Zomer, Aldert L

    2015-01-01

    The 7-valent pneumococcal conjugated vaccine (PCV7) has affected the genetic population of Streptococcus pneumoniae in pediatric carriage. Little is known however about pneumococcal population genomics in adult invasive pneumococcal disease (IPD) under vaccine pressure. We sequenced and serotyped

  17. Novel metabolic activity indicator in Streptococcus mutans biofilms

    NARCIS (Netherlands)

    Deng, D.M.; Hoogenkamp, M.A.; ten Cate, J.M.; Crielaard, W.

    2009-01-01

    Antimicrobial resistance of micro-organisms in biofilms requires novel strategies to evaluate the efficacy of caries preventive agents in actual biofilms. Hence we investigated fluorescence intensity (FI) in Streptococcus mutans biofilms constitutively expressing green fluorescent protein (GFP).

  18. Diversity of human small intestinal Streptococcus and Veillonella populations

    NARCIS (Netherlands)

    van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

    Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed

  19. Quantification of bovine oxylipids during intramammary Streptococcus uberis infection

    Science.gov (United States)

    Streptococcus uberis mastitis results in severe mammary tissue damage in dairy cows due to uncontrolled inflammation. Oxylipids are potent lipid mediators that orchestrate pathogen-induced inflammatory responses, however, changes in oxylipid biosynthesis during S. uberis mastitis are unknown. Thus, ...

  20. EFFECTS OF SHORT-TERM USE OF XYLITOL CHEWING GUM AND MOLTITOL ORAL SPRAY ON SALIVARY STREPTOCOCCUS MUTANS AND ORAL PLAQUE.

    Science.gov (United States)

    Mitrakul, Kemthong; Srisatjaluk, Ratchapin; Vongsawan, Kutkao; Teerawongpairoj, Chayanid; Choongphong, Nachata; Panich, Tathata; Kaewvimonrat, Pravee

    2017-03-01

    The purpose of this study was to investigate the short-term effects of xylitol chewing gum and maltitol spray on the concentration of salivary mutans streptococci (MS) and on the plaque index. Eighty-one second, third and fourth year dental and dental assistant students with a salivary MS concentration > 103 CFU/ml cultured on mitis salivarius bacitracin (MSB) agar were included in the study. The age range of subjects was 18-23 years. The participants were divided into 3 groups: control, xylitol chewing gum and maltitol spray groups. Each subject brushed their teeth with fluoridated toothpaste (1,000 ppm). Each subject in the xylitol chewing gum group was told to chew 2 pieces, 6 times a day (total xylitol dose=7.3 g/day) for 4 weeks. Each subject in the maltitol spray group was told to spray one puff twice daily (morning and evening) for 4 weeks. A dental examination and saliva samples to determine the salivary MS concentration were collected at baseline and at 2 and 4 weeks after experiment initiation. The nonparametric Mann–Whitney U test was used to analyze differences among groups. The mean ages in the control, xylitol chewing gum and maltitol spray groups were 22±1, 20±1 and 20±1 years, respectively. The mean MS concentrations at the beginning of the study and after 2 weeks in the control, and xylitol chewing gum and moltitol oral spray groups were not significantly different from each other. There was a significantly lower MS concentration in the moltitol oral spray group than in the control group by 4 weeks (p=0.045) but no significant difference between the control group and the xylitol gum group by 4 weeks. There were no significant differences in the mean plaque index at baseline among the control group, the xylitol chewing gum group and the moltitol oral spray group. The plaque index was significantly lower in the xylitol chewing gum group than the control group (p=0.003) at 2 weeks but not 4 weeks. There was no significant difference in the mean

  1. [Prevention of perinatal infection caused by group B beta-hemolytic streptococcus].

    Science.gov (United States)

    Bevilacqua, G

    1999-01-01

    Streptococcus agalactiae strains or group B streptococci (GBS) are the leading cause of bacterial pneumoniae, sepsis and meningitis in neonates. GBS is also a major cause of bacteriemia in pregnant women. Colonization of the human rectovaginal tract with GBS is a risk factor associated with chorioamnionitis and transmission of the infection to the infant. Neonatal exposure to high concentrations of GBS, mainly during vaginal delivery, leads to colonisation of the lung airways and subsequent onset of severe diseases like pneumonia, sepsis and menigitis. GBS is present in the genitourinary tract of 10% to 40% of pregnant women, about 50% of the newborns of these mothers will be colonised during delivery and of these neonates, 1% to 2% present a severe invasive disease. The early-onset disease, appear in the neonates within 7 days of life and more than 90% occur within the first day of life. Fatal infection is associated commonly with fulminat and overwhelming early-onset disease. Maternal-intrapartum chemoprophylaxis is able to prevent the transmission of GBS to the newborn and to reduce the frequency and the severity of early onset disease. In many countries, in particular in US, several recommendations have been proposed to prevent the perinatal GBS infection. In this paper some recommendations to prevent GBS disease of the newborn, performed in collaboration with Italian Society of Perinatal Medicine, are presented. The most important problem in the prevention programme is the identification of the cases to treat, since it is not possible to give antibiotics to all the women. We combine two strategies for the identification of the women to be treated, one risk based and the other screening based. Intra-partum administration of ampicillin or penicillin is recommended for the women with one or more risk-factors (labour = 18 hours, intrapartum temperature > = 38 degrees C, previous infant with invasive GBS disease, diabetes) and for women with collect vaginal and

  2. Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited

    DEFF Research Database (Denmark)

    Martens, Pernille; Worm, Signe Westring; Lundgren, Bettina

    2004-01-01

    Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited.Martens P, Worm SW, Lundgren B, Konradsen HB, Benfield T. Department of Infectious Diseases 144, Hvidovre University Hospital, DK-2650 Hvidovre, Denmark. pernillemartens@yahoo.com BACKGROUND: Invasive infection...... with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome. METHODS: Retrospective review of 464 cases of invasive disease among adults diagnosed...

  3. Heterologous expression of Ralp3 in Streptococcus pyogenes M2 and M6 strains affects the virulence characteristics.

    Directory of Open Access Journals (Sweden)

    Nikolai Siemens

    Full Text Available BACKGROUND: Ralp3 is a transcriptional regulator present in a serotype specific fashion on the chromosome of the human pathogen Streptococcus pyogenes (group A streptococci, GAS. In serotypes harbouring the ralp3 gene either positive or negative effects on important metabolic and virulence genes involved in colonization and immune evasion in the human host were observed. A previous study revealed that deletion of ralp3 in a GAS M49 serotype significantly attenuated many virulence traits and caused metabolic disadvantages. This leads to two questions: (i which kind of consequences could Ralp3 expression have in GAS serotypes naturally lacking this gene, and (ii is Ralp3 actively lost during evolution in these serotypes. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the role of Ralp3 in GAS M2 and M6 pathogenesis. Both serotypes lack ralp3 on their chromosome. The heterologous expression of ralp3 in both serotypes resulted in reduced attachment to and internalization into the majority of tested epithelial cells. Both ralp3 expression strains showed a decreased ability to survive in human blood and exclusively M2::ralp3 showed decreased survival in human serum. Both mutants secreted more active SpeB in the supernatant, resulting in a higher activity compared to wild type strains. The respective M2 and M6 wild type strains outcompeted the ralp3 expression strains in direct metabolic competition assays. The phenotypic changes observed in the M2:ralp3 and M6:ralp3 were verified on the transcriptional level. Consistent with the virulence data, tested genes showed transcript level changes in the same direction. CONCLUSIONS/SIGNIFICANCE: Together these data suggest that Ralp3 can take over transcriptional control of virulence genes in serotypes lacking the ralp3 gene. Those serotypes most likely lost Ralp3 during evolution since obviously expression of this gene is disadvantageous for metabolism and pathogenesis.

  4. Heterologous expression of Ralp3 in Streptococcus pyogenes M2 and M6 strains affects the virulence characteristics.

    Science.gov (United States)

    Siemens, Nikolai; Kreikemeyer, Bernd

    2013-01-01

    Ralp3 is a transcriptional regulator present in a serotype specific fashion on the chromosome of the human pathogen Streptococcus pyogenes (group A streptococci, GAS). In serotypes harbouring the ralp3 gene either positive or negative effects on important metabolic and virulence genes involved in colonization and immune evasion in the human host were observed. A previous study revealed that deletion of ralp3 in a GAS M49 serotype significantly attenuated many virulence traits and caused metabolic disadvantages. This leads to two questions: (i) which kind of consequences could Ralp3 expression have in GAS serotypes naturally lacking this gene, and (ii) is Ralp3 actively lost during evolution in these serotypes. We investigated the role of Ralp3 in GAS M2 and M6 pathogenesis. Both serotypes lack ralp3 on their chromosome. The heterologous expression of ralp3 in both serotypes resulted in reduced attachment to and internalization into the majority of tested epithelial cells. Both ralp3 expression strains showed a decreased ability to survive in human blood and exclusively M2::ralp3 showed decreased survival in human serum. Both mutants secreted more active SpeB in the supernatant, resulting in a higher activity compared to wild type strains. The respective M2 and M6 wild type strains outcompeted the ralp3 expression strains in direct metabolic competition assays. The phenotypic changes observed in the M2:ralp3 and M6:ralp3 were verified on the transcriptional level. Consistent with the virulence data, tested genes showed transcript level changes in the same direction. Together these data suggest that Ralp3 can take over transcriptional control of virulence genes in serotypes lacking the ralp3 gene. Those serotypes most likely lost Ralp3 during evolution since obviously expression of this gene is disadvantageous for metabolism and pathogenesis.

  5. Multiple length peptide-pheromone variants produced by Streptococcus pyogenes directly bind Rgg proteins to confer transcriptional regulation.

    Science.gov (United States)

    Aggarwal, Chaitanya; Jimenez, Juan Cristobal; Nanavati, Dhaval; Federle, Michael J

    2014-08-08

    Streptococcus pyogenes, a human-restricted pathogen, accounts for substantial mortality related to infections worldwide. Recent studies indicate that streptococci produce and respond to several secreted peptide signaling molecules (pheromones), including those known as short hydrophobic peptides (SHPs), to regulate gene expression by a quorum-sensing mechanism. Upon transport into the bacterial cell, pheromones bind to and modulate activity of receptor proteins belonging to the Rgg family of transcription factors. Previously, we reported biofilm regulation by the Rgg2/3 quorum-sensing circuit in S. pyogenes. The aim of this study was to identify the composition of mature pheromones from cell-free culture supernatants that facilitate biofilm formation. Bioluminescent reporters were employed to detect active pheromones in culture supernatants fractionated by reverse-phase chromatography, and mass spectrometry was used to characterize their properties. Surprisingly, multiple SHPs that varied by length were detected. Synthetic peptides of each variant were tested individually using bioluminescence reporters and biofilm growth assays, and although activities differed widely among the group, peptides comprising the C-terminal eight amino acids of the full-length native peptide were most active. Direct Rgg/SHP interactions were determined using a fluorescence polarization assay that utilized FITC-labeled peptide ligands. Peptide receptor affinities were seen to be as low as 500 nm and their binding affinities directly correlated with observed bioactivity. Revelation of naturally produced pheromones along with determination of their affinity for cognate receptors are important steps forward in designing compounds whose purpose is positioned for future therapeutics aimed at treating infections through the interference of bacterial communication. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. The GlnR Regulon in Streptococcus mutans Is Differentially Regulated by GlnR and PmrA.

    Directory of Open Access Journals (Sweden)

    Yi-Ywan M Chen

    Full Text Available GlnR-mediated repression of the GlnR regulon at acidic pH is required for optimal acid tolerance in Streptococcus mutans, the etiologic agent for dental caries. Unlike most streptococci, the GlnR regulon is also regulated by newly identified PmrA (SMUGS5_RS05810 at the transcriptional level in S. mutans GS5. Results from gel mobility shift assays confirmed that both GlnR and PmrA recognized the putative GlnR box in the promoter regions of the GlnR regulon genes. By using a chemostat culture system, we found that PmrA activated the expression of the GlnR regulon at pH 7, and that this activation was enhanced by excess glucose. Deletion of pmrA (strain ΔPmrA reduced the survival rate of S. mutans GS5 at pH 3 moderately, whereas the GlnR mutant (strain ΔGlnR exhibited an acid-sensitive phenotype in the acid killing experiments. Elevated biofilm formation in both ΔGlnR and ΔPmrA mutant strains is likely a result of indirect regulation of the GlnR regulon since GlnR and PmrA regulate the regulon differently. Taken together, it is suggested that activation of the GlnR regulon by PmrA at pH 7 ensures adequate biosynthesis of amino acid precursor, whereas repression by GlnR at acidic pH allows greater ATP generation for acid tolerance. The tight regulation of the GlnR regulon in response to pH provides an advantage for S. mutans to better survive in its primary niche, the oral cavity.

  7. Streptococcal adhesin SspA/B analogue peptide inhibits adherence and impacts biofilm formation of Streptococcus mutans.

    Directory of Open Access Journals (Sweden)

    Tatsuro Ito

    Full Text Available Streptococcus mutans, the major causative agent of dental caries, adheres to tooth surfaces via the host salivary glycoprotein-340 (gp340. This adherence can be competitively inhibited by peptides derived from the SspA/B adhesins of Streptococcus gordonii, a human commensal microbe that competes for the same binding sites. Ssp(A4K-A11K, a double-lysine substituted SspA/B peptide analogue, has been shown to exhibit superior in vitro binding affinity for a gp340-derived peptide (SRCRP2, suggesting that Ssp(A4K-A11K may be of clinical interest. In the present work, we tested the inhibitory effects of Ssp(A4K-A11K on adherence and biofilm formation of S. mutans by reconstructing an artificial oral environment using saliva-coated polystyrene plates and hydroxyapatite disks. Bacterial adherence (adherence period: 1 h was assessed by an enzyme-linked immunosorbent assay using biotinylated bacterial cells. Biofilm formation (periods: 8, 11, or 14 h was assessed by staining and imaging of the sessile cells, or by recovering biofilm cells and plating for cell counts. The pH values of the culture media were measured as a biofilm acidogenicity indicator. Bactericidality was measured by loss of optical density during culturing in the presence of the peptide. We observed that 650 μM Ssp(A4K-A11K significantly inhibited adherence of S. mutans to saliva-coated polystyrene; a similar effect was seen on bacterial affinity for SRCRP2. Ssp(A4K-A11K had lesser effects on the adherence of commensal streptococci. Pretreatment of polystyrene and hydroxyapatite with 650 μM Ssp(A4K-A11K significantly attenuated biofilm formation, whether tested with glucose- or sucrose-containing media. The SspA/B peptide's activity did not reflect bactericidality. Strikingly, pH in Ssp-treated 8-h (6.8 ± 0.06 and 11-h (5.5 ± 0.06 biofilms showed higher values than the critical pH. Thus, Ssp(A4K-A11K acts by inhibiting bacterial adherence and cariogrnic biofilm formation. We further

  8. Development of Primer Sets for Loop-Mediated Isothermal Amplification that Enables Rapid and Specific Detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    Deguo Wang

    2015-05-01

    Full Text Available Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP for identification and differentiation of these three pathogens are not available. With the 16S rRNA gene and 16S-23S rRNA intergenic spacers as targets, four sets of LAMP primers were designed for identification and differentiation of S. dysgalactiae, S. uberis and S. agalactiae. The detection limit of all four LAMP primer sets were 0.1 pg DNA template per reaction, the LAMP method with 16S rRNA gene and 16S-23S rRNA intergenic spacers as the targets can differentiate the three pathogens, which is potentially useful in epidemiological studies.

  9. Development of Primer Sets for Loop-Mediated Isothermal Amplification that Enables Rapid and Specific Detection of Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae.

    Science.gov (United States)

    Wang, Deguo; Liu, Yanhong

    2015-05-26

    Streptococcus dysgalactiae, Streptococcus uberis and Streptococcus agalactiae are the three main pathogens causing bovine mastitis, with great losses to the dairy industry. Rapid and specific loop-mediated isothermal amplification methods (LAMP) for identification and differentiation of these three pathogens are not available. With the 16S rRNA gene and 16S-23S rRNA intergenic spacers as targets, four sets of LAMP primers were designed for identification and differentiation of S. dysgalactiae, S. uberis and S. agalactiae. The detection limit of all four LAMP primer sets were 0.1 pg DNA template per reaction, the LAMP method with 16S rRNA gene and 16S-23S rRNA intergenic spacers as the targets can differentiate the three pathogens, which is potentially useful in epidemiological studies.

  10. Comprehensive update of dalbavancin activity when tested against uncommonly isolated streptococci, Corynebacterium spp., Listeria monocytogenes, and Micrococcus spp. (1357 strains).

    Science.gov (United States)

    Jones, Ronald N; Stilwell, Matthew G

    2013-06-01

    Dalbavancin is an investigational lipoglycopeptide having an extended serum elimination half-life allowing once-weekly dosing. Data from testing 1357 strains of uncommonly isolated species expand the dalbavancin spectrum details as follows (MIC50/90): β-haemolytic streptococcal serogroups C, F, and G (≤0.03/≤0.03 μg/mL), 7 viridans group of streptococci (≤0.03/≤0.03-0.06 μg/mL), 5 Corynebacterium spp. (0.06/0.12 μg/mL), Listeria monocytogenes (0.06/0.12 μg/mL), and Micrococcus spp. (≤0.03/≤0.03 μg/mL). Among all reported isolates, 99.8% of tested strains were inhibited at dalbavancin MIC values at ≤0.12 μg/mL. Dalbavancin remains very potent against rarer Gram-positive pathogens, using in vitro test experience with organisms cultured through 2011. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Crystallization and preliminary X-ray analysis of βC–S lyases from two oral streptococci

    International Nuclear Information System (INIS)

    Kezuka, Yuichiro; Yoshida, Yasuo; Nonaka, Takamasa

    2009-01-01

    The βC-S lyases from two oral bacteria, Streptococcus anginosus and S. gordonii, were cloned, overproduced, purified and crystallized. The obtained crystals were characterized by X-ray diffraction. Hydrogen sulfide, which causes oral malodour, is generally produced from l-cysteine by the action of βC–S lyase from oral bacteria. The βC–S lyases from two oral bacteria, Streptococcus anginosus and S. gordonii, have been cloned, overproduced, purified and crystallized. X-ray diffraction data were collected from the two types of crystals using synchrotron radiation. The crystal of S. anginosus βC–S lyase belonged to the orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 67.0, b = 111.1, c = 216.4 Å, and the crystal of S. gordonii βC–S lyase belonged to the same space group, with unit-cell parameters a = 58.0, b = 73.9. c = 187.6 Å. The structures of the βC–S lyases were solved by molecular-replacement techniques

  12. Streptococcus pyogenes pharyngeal colonization resulting in recurrent, prepubertal vulvovaginitis.

    Science.gov (United States)

    Hansen, Megan T; Sanchez, Veronica T; Eyster, Kathleen; Hansen, Keith A

    2007-10-01

    Recurrent, prepubertal, vaginal infections are an uncommon, troublesome problem for the patient and her family. Failure of initial therapy to alleviate vulvovaginitis may be related to vulvar skin disease, foreign body, sexual abuse, pinworms, reactions to medications, anatomic anomalies, or allergies. This report describes a case of recurrent Streptococcus pyogenes vulvovaginitis secondary to presumed vaginal re-inoculation from pharyngeal colonization. A 4-yr-old presented with one year of culture proven, recurrent Streptococcus pyogenes vulvovaginitis. Her symptoms repeatedly resolved with penicillin therapy, but continued to recur following cessation of antibiotic therapy. Evaluation included physical examination, trans-abdominal pelvic ultrasound, and vaginoscopy which all revealed normal upper and lower genital tract anatomy. Both the patient and her mother demonstrated culture proven, Group A Streptococcus pharyngeal colonization. Because of the possibility of repeated inoculations of the vaginal area from the colonized pharynx, they were both treated for decolonization with a regimen of amoxicillin and rifampin for ten days. Following this therapy there was resolution of vaginal symptoms with no further recurrence. Follow-up pharyngeal culture done on both mother and child on their last visit were negative for Group A Streptococcus. This case demonstrated an unusual specific cause of recurrent vaginitis resulting from presumed self or maternal re-inoculation with group A beta-hemolytic streptococcus from pharyngeal colonization. Group A beta-hemolytic streptococcus are consistently sensitive to penicillin, but up to 25% of acute pharyngitis cases treated with penicillin having continued asymptomatic, bacterial carriage within the nasopharynx. Thus initial alleviation of symptoms in a patient with Group A beta-hemolytic vulvovaginitis treated with penicillin, can have continued asymptomatic pharyngeal colonization which can result in recurrence of the

  13. Características laboratoriais das ceratites e conjuntivites causadas por Streptococcus sp Laboratorial findings of Streptococcus keratitis and conjunctivitis

    Directory of Open Access Journals (Sweden)

    Helena Parente Solari

    2004-10-01

    Full Text Available OBJETIVOS: Analisar os resultados laboratoriais de conjuntivites e ceratites com cultura positiva para Streptococcus sp, avaliando a incidência das diferentes espécies e os dados dos antibiogramas. MÉTODOS: Estudo retrospectivo de revisão de prontuários de pacientes encaminhados ao laboratório de Doenças Externas do Departamento de Oftalmologia da UNIFESP com resultado de cultivo bacteriano positivo de córnea ou conjuntiva e com identificação de alguma cepa do gênero Streptococcus sp, no período de janeiro de 1995 a dezembro de 2001. Analisou-se idade do paciente, espécie de Streptococcus e os testes de sensibilidade aos seguintes antibióticos: cefalotina, amicacina, gentamicina, tobramicina, ciprofloxacina, lomefloxacina, ofloxacina, norfloxacina e vancomicina. RESULTADOS: As espécies mais encontradas foram Streptococcus pneumoniae e Streptococcus viridans. Com relação aos antibióticos, a sensibilidade foi maior à cefalotina, às quinolonas e à vancomicina. CONCLUSÕES: Considerando-se os antibióticos tópicos comercialmente disponíveis, as quinolonas apresentam melhor espectro de ação quando comparadas aos aminoglicosídios.PURPOSE: To evaluate laboratorial findings of Streptococcus keratitis and conjunctivitis, analyzing the different species and the results of bacterial susceptibility to an antibiotics. METHODS: Retrospective study of the records from the External Disease Laboratory of the Ophthalmology Department of the Federal University of São Paulo, with conjunctival or corneal positive bacterial culture for Streptococcus sp, between January 1995 and December 2001. The collected data were age, Streptococcus species and the bacterial susceptibility to the following antibiotics: cephalotin, amikacin, gentamicin, tobramicin, ciprofloxacin, lomefloxacin, ofloxacin, norfloxacin and vancomicin. RESULTS: The most frequent species were Streptococcus pneumoniae and Streptococcus viridans. Regarding bacterial

  14. Molecular and mathematical epidemiology of Staphylococcus aureus and Streptococcus uberis mastitis in dairy herds

    NARCIS (Netherlands)

    Zadoks, Ruth Nicolet

    2002-01-01

    Mastitis is the most common and costly production disease affecting dairy cows. Staphylococcus aureus and Streptococcus uberis are two major mastitis-causing pathogens. Staphylococcus aureus is traditionally classified as contagious pathogen, while Streptococcus uberis is classified as environmental

  15. Ornithine transport and exchange in Streptococcus lactis

    International Nuclear Information System (INIS)

    Thompson, J.

    1987-01-01

    Resting cells of Streptococcus lactis 133 appeared to accumulate [ 14 C]ornithine to a high concentration in the absence of an exogenous energy source. However, analysis of intracellular amino acid pool constituents and results of transport experiments revealed that the accumulation of ornithine represented a homoexchange between extracellular [ 14 C]ornithine and unlabeled ornithine in the cell. The energy-independent exchange of ornithine was not inhibited by proton-conducting uncouplers or by metabolic inhibitors. Intracellular [ 14 C]ornithine was retained by resting cells after suspension in a buffered medium. However, addition of unlabeled ornithine to the suspension elicited rapid exit of labeled amino acid. The initial rate of exist of [ 14 C]ornithine was dependent on the concentration of unlabeled ornithine in the medium, but this accelerative exchange diffusion process caused no net loss of amino acid. By contrast, the presence of a fermentable energy source caused a rapid expulsion of and new decrease in the concentration of intracellular ornithine. Kinetic analyses of amino acid transport demonstrated competitive inhibition between lysine and ornithine, and data obtained by two-dimensional thin-layer chromatography established the heteroexchange of these basic amino acids. The effects of amino acids and of ornithine analogs on both entry and exit of [ 14 C]ornithine have been examined. The data suggest that common carrier mediates the entry and exchange of lysine, arginine, and ornithine in cells of S. lactis

  16. Ecology and pathogenicity of gastrointestinal Streptococcus bovis.

    Science.gov (United States)

    Herrera, Paul; Kwon, Young Min; Ricke, Steven C

    2009-01-01

    Streptococcus bovis is an indigenous resident in the gastrointestinal tracts of both humans and animals. S. bovis is one of the major causes of bacterial endocarditis and has been implicated in the incidence of human colon cancer, possibly due to chronic inflammatory response at the site of intestinal colonization. Certain feeding regimens in ruminants can lead to overgrowth of S. bovis in the rumen, resulting in the over-production of lactate and capsular polysaccharide causing acute ruminal acidosis and bloat, respectively. There are multiple strategies in controlling acute lactic acidosis and bloat. The incidence of the two diseases may be controlled by strict dietary management. Gradual introduction of grain-based diets and the feeding of coarsely chopped roughage decrease the incidence of the two disease entities. Ionophores, which have been used to enhance feed conversion and growth rate in cattle, have been shown to inhibit the growth of lactic acid bacteria in the rumen. Other methods of controlling lactic acid bacteria in the ruminal environment (dietary supplementation of long-chain fatty acids, induction of passive and active immune responses to the bacteria, and the use of lytic bacteriophages) have also been investigated. It is anticipated that through continued in-depth ecological analysis of S. bovis the characteristics responsible for human and animal pathogenesis would be sufficiently identified to a point where more effective control strategies for the control of this bacteria can be developed.

  17. Peptide pheromone signaling in Streptococcus and Enterococcus

    Science.gov (United States)

    Cook, Laura C.; Federle, Michael J.

    2014-01-01

    Intercellular chemical signaling in bacteria, commonly referred to as quorum sensing (QS), relies on the production and detection of compounds known as pheromones to elicit coordinated responses among members of a community. Pheromones produced by Gram-positive bacteria are comprised of small peptides. Based on both peptide structure and sensory system architectures, Gram-positive bacterial signaling pathways may be classified into one of four groups with a defining hallmark: cyclical peptides of the Agr type, peptides that contain Gly-Gly processing motifs, sensory systems of the RNPP family, or the recently characterized Rgg-like regulatory family. The recent discovery that Rgg family members respond to peptide pheromones increases substantially the number of species in which QS is likely a key regulatory component. These pathways control a variety of fundamental behaviors including conjugation, natural competence for transformation, biofilm development, and virulence factor regulation. Overlapping QS pathways found in multiple species and pathways that utilize conserved peptide pheromones provide opportunities for interspecies communication. Here we review pheromone signaling identified in the genera Enterococcus and Streptococcus, providing examples of all four types of pathways. PMID:24118108

  18. Efflux inhibitor suppresses Streptococcus mutans virulence properties.

    Science.gov (United States)

    Zeng, Huihui; Liu, Jia; Ling, Junqi

    2017-04-01

    It is well established that efflux pumps play important roles in bacterial pathogenicity and efflux inhibitors (EIs) have been proved to be effective in suppressing bacterial virulence properties. However, little is known regarding the EI of Streptococcus mutans, a well-known caries-inducing bacterium. In this study, we identified the EI of S. mutans through ethidium bromide efflux assay and investigated how EI affected S. mutans virulence regarding the cariogenicity and stress response. Results indicated that reserpine, the identified EI, suppressed acid tolerance, mutacin production and transformation efficiency of S. mutans, and modified biofilm architecture and extracellular polysaccharide distribution. Suppressed glycosyltransferase activity was also noted after reserpine exposure. The data from quantitative real-time-PCR demonstrated that reserpine significantly altered the expression profile of quorum-sensing and virulence-associated genes. These findings suggest that reserpine represents a promising adjunct anticariogenic agent in that it suppresses virulence properties of S. mutans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Lactam inhibiting Streptococcus mutans growth on titanium

    Energy Technology Data Exchange (ETDEWEB)

    Xavier, J.G.; Geremias, T.C.; Montero, J.F.D. [Center for Research on Dental Implants (CEPID), School of Dentistry (ODT), Federal University of Santa Catarina - UFSC, Florianópolis/SC, 88040-900 (Brazil); Vahey, B.R. [Herman Ostrow School of Dentistry of USC, 925 W 34 St, Los Angeles, CA 90089 (United States); Benfatti, C.A.M.; Souza, J.C.M.; Magini, R.S. [Center for Research on Dental Implants (CEPID), School of Dentistry (ODT), Federal University of Santa Catarina - UFSC, Florianópolis/SC, 88040-900 (Brazil); Pimenta, A.L., E-mail: andrea@intelab.ufsc.br [Department of Biologia, ERRMECe, Université de Cergy Pontoise, 2, Av. Adolphe Chauvin 95302 Cergy, Pontoise (France); Integrated Laboratories Technologies (InteLab), Dept. Chemical and Food Engineering (EQA), Federal University of Santa Catarina - UFSC, Florianópolis/SC, 88040-970 (Brazil)

    2016-11-01

    The aim of this work was to analyze the activity of novel synthetic lactams on preventing biofilm formation on titanium surfaces. Titanium (Ti6Al4V) samples were exposed to Streptococcus mutans cultures in the presence or absence of a synthetic lactam. After 48 h incubation, planktonic growth was determined by spectrophotometry. Biofilm was evaluated by crystal violet staining and colony forming units (CFU·ml{sup −1}), followed by scanning electron microscopy (SEM). Results showed that the average of adhered viable cells was approximately 1.5 × 10{sup 2} CFU/ml in the presence of lactam and 4 × 10{sup 2} CFU/ml in its absence. This novel compound was considerable active in reducing biofilm formation over titanium surfaces, indicating its potential for the development of antimicrobial drugs targeting the inhibition of the initial stages of bacterial biofilms on dental implants abutments. - Highlights: • A novel synthetic compound is tested on preventing biofilm formation on titanium surfaces • Biofilm inhibition has been achieved on titanium surfaces containing the novel compound. • Planktonic growth of S. mutans was not affected by the presence of lactams on titanium.

  20. Lactam inhibiting Streptococcus mutans growth on titanium

    International Nuclear Information System (INIS)

    Xavier, J.G.; Geremias, T.C.; Montero, J.F.D.; Vahey, B.R.; Benfatti, C.A.M.; Souza, J.C.M.; Magini, R.S.; Pimenta, A.L.

    2016-01-01

    The aim of this work was to analyze the activity of novel synthetic lactams on preventing biofilm formation on titanium surfaces. Titanium (Ti6Al4V) samples were exposed to Streptococcus mutans cultures in the presence or absence of a synthetic lactam. After 48 h incubation, planktonic growth was determined by spectrophotometry. Biofilm was evaluated by crystal violet staining and colony forming units (CFU·ml −1 ), followed by scanning electron microscopy (SEM). Results showed that the average of adhered viable cells was approximately 1.5 × 10 2 CFU/ml in the presence of lactam and 4 × 10 2 CFU/ml in its absence. This novel compound was considerable active in reducing biofilm formation over titanium surfaces, indicating its potential for the development of antimicrobial drugs targeting the inhibition of the initial stages of bacterial biofilms on dental implants abutments. - Highlights: • A novel synthetic compound is tested on preventing biofilm formation on titanium surfaces • Biofilm inhibition has been achieved on titanium surfaces containing the novel compound. • Planktonic growth of S. mutans was not affected by the presence of lactams on titanium.

  1. Sorption of streptococcus faecium to glass

    International Nuclear Information System (INIS)

    Oerstavik, D.

    1977-01-01

    A method has been developed by which to study the sorption of Streptococcus faecium to soda-lime cover glasses. Conditions were chosen to minimize the influence on sorption of bacterial polymer production, passive sorption being studied rather than attachment mediated by metabolic activities. Sorption of S. faecium increased with increasing temperature (to 50degC), time, and cell concentration, but equilibrium apparently was not reached even after incubation for 8 hours or at a cell concentration of 3 x 10 10 per ml. Sorption increased with solute molarity up to 0.1 M concentration of NaCl and KCl, indicating an effect of the electrical double layers on the apposition of cells to the glass surface. Desorption of bacteria could be obtained after multiple washings of the glasses in buffer or by the action of Tween 80, but not if sorbed bacteria were left in distilled water, various salt solutions, urea, or in suspensions of unlabelled bacteria. It was concluded that sorption occurred as a result of chemical interactions between the glass and the cell surface. Tween 80 at a concentration of 1 per cent inhibited sorption to 26 per cent of buffer controls, 2 M urea was less effective, and 1 M NaCl was without effect. It is suggested that hydrophobic interactions may be of importance in the binding of S. faecium to glass. (author)

  2. In Vitro Effect of Zingiber officinale Extract on Growth of Streptococcus mutans and Streptococcus sanguinis.

    Science.gov (United States)

    Azizi, Arash; Aghayan, Shabnam; Zaker, Saeed; Shakeri, Mahdieh; Entezari, Navid; Lawaf, Shirin

    2015-01-01

    Background and Objectives. Tooth decay is an infectious disease of microbial origin. Considering the increasing prevalence of antibiotic resistance due to their overuse and also their side effects, medicinal plants are now considered for use against bacterial infections. This study aimed to assess the effects of different concentrations of Zingiber officinale extract on proliferation of Streptococcus mutans and Streptococcus sanguinis in vitro. Materials and Methods. In this experimental study, serial dilutions of the extract were prepared in two sets of 10 test tubes for each bacterium (total of 20). Standard amounts of bacterial suspension were added; 100ƛ of each tube was cultured on prepared solid agar plates and incubated at 37°C for 24 hours. Serial dilutions of the extract were prepared in another 20 tubes and 100ƛ of each tube was added to blood agar culture medium while being prepared. The mixture was transferred to the plates. The bacteria were inoculated on plates and incubated as described. Results. The minimum inhibitory concentration (MIC) was 0.02 mg/mL for S. mutans and 0.3 mg/mL for S. sanguinis. The minimum bactericidal concentration (MBC) was 0.04 mg for S. mutans and 0.6 mg for S. sanguinis. Conclusion. Zingiber officinale extract has significant antibacterial activity against S. mutans and S. sanguinis cariogenic microorganisms.

  3. In Vitro Effect of Zingiber officinale Extract on Growth of Streptococcus mutans and Streptococcus sanguinis

    Directory of Open Access Journals (Sweden)

    Arash Azizi

    2015-01-01

    Full Text Available Background and Objectives. Tooth decay is an infectious disease of microbial origin. Considering the increasing prevalence of antibiotic resistance due to their overuse and also their side effects, medicinal plants are now considered for use against bacterial infections. This study aimed to assess the effects of different concentrations of Zingiber officinale extract on proliferation of Streptococcus mutans and Streptococcus sanguinis in vitro. Materials and Methods. In this experimental study, serial dilutions of the extract were prepared in two sets of 10 test tubes for each bacterium (total of 20. Standard amounts of bacterial suspension were added; 100ƛ of each tube was cultured on prepared solid agar plates and incubated at 37°C for 24 hours. Serial dilutions of the extract were prepared in another 20 tubes and 100ƛ of each tube was added to blood agar culture medium while being prepared. The mixture was transferred to the plates. The bacteria were inoculated on plates and incubated as described. Results. The minimum inhibitory concentration (MIC was 0.02 mg/mL for S. mutans and 0.3 mg/mL for S. sanguinis. The minimum bactericidal concentration (MBC was 0.04 mg for S. mutans and 0.6 mg for S. sanguinis. Conclusion. Zingiber officinale extract has significant antibacterial activity against S. mutans and S. sanguinis cariogenic microorganisms.

  4. Inhibitory effects of antiseptic mouthrinses on Streptococcus mutans, Streptococcus sanguinis and Lactobacillus acidophilus.

    Science.gov (United States)

    Evans, A; Leishman, S J; Walsh, L J; Seow, W K

    2015-06-01

    Oral antiseptics are valuable in controlling oral infections caused by cariogenic bacteria. The aim of this study was to investigate the effects of mouthrinses and pure antiseptic compounds on Streptococcus mutans and non-mutans bacteria (Streptococcus sanguinis and Lactobacillus acidophilus). The agar diffusion assay was employed to determine bacterial growth inhibition. Commercial mouthrinses containing chlorhexidine gluconate (0.2%), cetylpyridinium chloride (0.05%) and sodium fluoride (0.05%) produced statistically similar growth inhibition of S. mutans, S. sanguinis and L. acidophilus (with zones of inhibition ranging from 7.56 ± 0.52 mm to 7.39 ± 0.53 mm, 17.44 ± 0.94 mm to 18.31 ± 0.62 mm and 8.61 ± 1.43 to 8.67 ± 1.43 mm respectively, p > 0.05). The chlorhexidine mouthwash produced the greatest mean growth inhibition of S. sanguinis and S. mutans compared to all other mouthrinses tested (p mutans could be detected were chlorhexidine gluconate at 0.005% (wt/vol), cetylpyridinium chloride 0.01% (wt/ vol), povidone iodine 10% (wt/vol) and sodium hypochlorite 0.5% (vol/vol). Chlorhexidine (0.01%), cetylpyridinium chloride (0.01%), povidone iodine (10%) and sodium hypochlorite (0.5%) are effective at inhibiting the growth of S. mutans, S. sanguinis and L. acidophilus. © 2015 Australian Dental Association.

  5. In-vitro efficacy of different morphology zinc oxide nanopowders on Streptococcus sobrinus and Streptococcus mutans.

    Science.gov (United States)

    Mohd Bakhori, Siti Khadijah; Mahmud, Shahrom; Ling, Chuo Ann; Sirelkhatim, Amna Hassan; Hasan, Habsah; Mohamad, Dasmawati; Masudi, Sam'an Malik; Seeni, Azman; Abd Rahman, Rosliza

    2017-09-01

    ZnO with two different morphologies were used to study the inhibition of Streptococcus sobrinus and Streptococcus mutans which are closely associated with tooth cavity. Rod-like shaped ZnO-A and plate-like shaped ZnO-B were produced using a zinc boiling furnace. The nanopowders were characterized using energy filtered transmission electron microscopy (EFTEM), X-ray diffraction (XRD), photoluminescence (PL) spectroscopy, Raman spectroscopy and dynamic light scattering (DLS) to confirm the properties of the ZnO polycrystalline wurtzite structures. XRD results show that the calculated crystallite sizes of ZnO-A and ZnO-B were 36.6 and 39.4nm, respectively, whereas DLS revealed particle size distributions of 21.82nm (ZnO-A) and 52.21nm (ZnO-B). PL spectra showed ion vacancy defects related to green and red luminescence for both ZnO particles. These defects evolved during the generation of reactive oxygen species which contributed to the antibacterial activity. Antibacterial activity was investigated using microdilution technique towards S. sobrinus and S. mutans at different nanopowder concentrations. Results showed that ZnO-A exhibited higher inhibition on both bacteria compared with ZnO-B. Moreover, S. mutans was more sensitive compared with S. sobrinus because of its higher inhibition rate. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Distinct Biological Potential of Streptococcus gordonii and Streptococcus sanguinis Revealed by Comparative Genome Analysis.

    Science.gov (United States)

    Zheng, Wenning; Tan, Mui Fern; Old, Lesley A; Paterson, Ian C; Jakubovics, Nicholas S; Choo, Siew Woh

    2017-06-07

    Streptococcus gordonii and Streptococcus sanguinis are pioneer colonizers of dental plaque and important agents of bacterial infective endocarditis (IE). To gain a greater understanding of these two closely related species, we performed comparative analyses on 14 new S. gordonii and 5 S. sanguinis strains using various bioinformatics approaches. We revealed S. gordonii and S. sanguinis harbor open pan-genomes and share generally high sequence homology and number of core genes including virulence genes. However, we observed subtle differences in genomic islands and prophages between the species. Comparative pathogenomics analysis identified S. sanguinis strains have genes encoding IgA proteases, mitogenic factor deoxyribonucleases, nickel/cobalt uptake and cobalamin biosynthesis. On the contrary, genomic islands of S. gordonii strains contain additional copies of comCDE quorum-sensing system components involved in genetic competence. Two distinct polysaccharide locus architectures were identified, one of which was exclusively present in S. gordonii strains. The first evidence of genes encoding the CylA and CylB system by the α-haemolytic S. gordonii is presented. This study provides new insights into the genetic distinctions between S. gordonii and S. sanguinis, which yields understanding of tooth surfaces colonization and contributions to dental plaque formation, as well as their potential roles in the pathogenesis of IE.

  7. INTERACTION BETWEEN DIFFERENT MOLECULAR FORMS OF IMMUNOGLOBULIN A AND RECOMBINANT DERIVATIVES POLYPEPTIDES OF BAC RECEPTOR PROTEINS FROM GROUP B STREPTOCOCCI

    Directory of Open Access Journals (Sweden)

    A. S. Korzhueva

    2008-01-01

    Full Text Available Abstract. The article concerns interactions between immunoglobulin A and recombinant P6, P7, P8 polypeptides, designed on the basis of externally localized Bac protein of the Group B streptococci, possessing IgA-binding activity.There is a current demand for immunochemical reagents that are strictly specific for IgA, in order to develop antigenic standards for detection of IgA levels in biological fluids, as well as for affinity purification of IgA and its fragments.To analyze an opportunity of the abovementioned application ways for these proteins, a special study was performed to assay an interaction capability of recombinant P6, P7, P8 polypeptides binding to Fc regions of different IgA forms (serum IgA, secretory IgA, subclasses of serum IgA – IgA1, IgA2. Selectivity of ligand binding was specially confirmed.It was found out that, among three presented polypeptides, the structure of recombinant P6 derivative proved to be optimal for IgA-binding ability of Bac protein.Structural features of IgA-binding fragments of Bac protein, i.e., binding site position on the IgA molecule (proximity to epitopes for three monoclonal antibodies, variability of the site structure, as well as resistance of binding site for P6, P7, P8 in IgA molecule against partial disulfide bonds reduction. (Med. Immunol., vol. 10, N 4-5, pp 327-336.

  8. Lactobacillus reuteri influences regrowth of mutans streptococci after full-mouth disinfection: a double-blind, randomised controlled trial.

    Science.gov (United States)

    Romani Vestman, N; Hasslöf, P; Keller, M K; Granström, E; Roos, S; Twetman, S; Stecksén-Blicks, C

    2013-01-01

    This study assessed whether the persistence of Lactobacillus reuteri DSM 17938 and ATCC PTA 5289 in saliva could delay the regrowth of mutans streptococci (MS) after a full-mouth disinfection with chlorhexidine (CHX). A randomised, double-blind, placebo-controlled study with a 6-week intervention period and 3- and 6-month follow-up was performed. 62 healthy subjects with moderate to high counts of MS were randomly assigned to a test group (n = 32) or a placebo group (n = 30). Before onset of the intervention, subjects received two sessions of professional cleaning, flossing, and application of CHX varnish and rinsed their mouth with a CHX solution between the sessions (2 days). Thereafter, the test group used probiotic lozenges (2/day) containing L. reuteri (DSM 17938 and ATCC PTA 5289; 1 × 10(8) CFU of each strain), and the placebo group used identical lozenges lacking the lactobacilli. Saliva samples were collected and cultured onto selective media, and isolates of L. reuteri as well as DNA directly extracted from saliva were tested by polymerase chain reaction (PCR) with specific primers. Presence of salivary MS was analysed with a chair-side test. L. reuteri was frequently detected by culture during the intervention period but in only 3 test group subjects at follow-ups. Regrowth of MS statistically significantly differed depending on the presence or absence of L. reuteri DSM 17938 detected by PCR. We conclude that cultivable L. reuteri strains may only sporadically be confirmed after termination of the intervention, but subjects with PCR-detected L. reuteri demonstrated slower regrowth of MS. Copyright © 2013 S. Karger AG, Basel.

  9. 21 CFR 866.3720 - Streptococcus spp. exo-enzyme reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Streptococcus spp. exo-enzyme reagents. 866.3720... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3720 Streptococcus spp. exo-enzyme reagents. (a) Identification. Streptococcus spp. exoenzyme reagents are devices used...

  10. Lung abscess caused by Streptococcus pneumoniae serotype 6B

    Directory of Open Access Journals (Sweden)

    Yuhei Ito

    Full Text Available Lung abscess has been considered to be a rare complication of pneumococcal infection, and most cases are reported to be Streptococcus pneumoniae serotype 3. A 67-year-old man presented with fever and was diagnosed to have lung abscess caused by S. pneumoniae serotype 6B. The minimal inhibitory concentration (MIC of penicillin for the isolate was 1 μg/mL. He was treated with high-dose intravenous sulbactam/ampicillin as definitive therapy based on susceptibility testing for S. pneumoniae and recovered successfully without surgical intervention. S. pneumoniae serotype 6B can cause lung abscess. Keywords: Streptococcus pneumoniae, Lung abscess, Serotype 6B, Penicillin-resistant Streptococcus pneumoniae

  11. Chlorophyll mediated photodynamic inactivation of blue laser on Streptococcus mutans

    Science.gov (United States)

    Astuti, Suryani Dyah; Zaidan, A.; Setiawati, Ernie Maduratna; Suhariningsih

    2016-03-01

    Photodynamic inactivation is an inactivation method in microbial pathogens that utilize light and photosensitizer. This study was conducted to investigate photodynamic inactivation effects of low intensity laser exposure with various dose energy on Streptococcus mutans bacteria. The photodynamic inactivation was achieved with the addition of chlorophyll as photosensitizers. To determine the survival percentage of Streptococcus mutans bacteria after laser exposure, the total plate count method was used. For this study, the wavelength of the laser is 405 nm and variables of energy doses are 1.44, 2.87, 4.31, 5.74, 7.18, and 8.61 in J/cm2. The results show that exposure to laser with energy dose of 7.18 J/cm2 has the best photodynamic inactivation with a decrease of 78% in Streptococcus

  12. Streptococcus pneumoniae necrotizing fasciitis in systemic lupus erythematosus.

    Science.gov (United States)

    Sánchez, A; Robaina, R; Pérez, G; Cairoli, E

    2016-04-01

    Necrotizing fasciitis is a rapidly progressive destructive soft tissue infection with high mortality. Streptococcus pneumoniae as etiologic agent of necrotizing fasciitis is extremely unusual. The increased susceptibility to Streptococcus pneumoniae infection in patients with systemic lupus erythematosus is probably a multifactorial phenomenon. We report a case of a patient, a 36-year-old Caucasian female with 8-year history of systemic lupus erythematosus who presented a fatal Streptococcus pneumoniae necrotizing fasciitis. The role of computed tomography and the high performance of blood cultures for isolation of the causative microorganism are emphasized. Once diagnosis is suspected, empiric antibiotic treatment must be prescribed and prompt surgical exploration is mandatory. © The Author(s) 2015.

  13. RovS and its associated signaling peptide form a cell-to-cell communication system required for Streptococcus agalactiae pathogenesis.

    Science.gov (United States)

    Pérez-Pascual, David; Gaudu, Philippe; Fleuchot, Betty; Besset, Colette; Rosinski-Chupin, Isabelle; Guillot, Alain; Monnet, Véronique; Gardan, Rozenn

    2015-01-20

    Bacteria can communicate with each other to coordinate their biological functions at the population level. In a previous study, we described a cell-to-cell communication system in streptococci that involves a transcriptional regulator belonging to the Rgg family and short hydrophobic peptides (SHPs) that act as signaling molecules. Streptococcus agalactiae, an opportunistic pathogenic bacterium responsible for fatal infections in neonates and immunocompromised adults, has one copy of the shp/rgg locus. The SHP-associated Rgg is called RovS in S. agalactiae. In this study, we found that the SHP/RovS cell-to-cell communication system is active in the strain NEM316 of S. agalactiae, and we identified different partners that are involved in this system, such as the Eep peptidase, the PptAB, and the OppA1-F oligopeptide transporters. We also identified a new target gene controlled by this system and reexamined the regulation of a previously proposed target gene, fbsA, in the context of the SHP-associated RovS system. Furthermore, our results are the first to indicate the SHP/RovS system specificity to host liver and spleen using a murine model, which demonstrates its implication in streptococci virulence. Finally, we observed that SHP/RovS regulation influences S. agalactiae's ability to adhere to and invade HepG2 hepatic cells. Hence, the SHP/RovS cell-to-cell communication system appears to be an essential mechanism that regulates pathogenicity in S. agalactiae and represents an attractive target for the development of new therapeutic strategies. Rgg regulators and their cognate pheromones, called small hydrophobic peptides (SHPs), are present in nearly all streptococcal species. The general pathways of the cell-to-cell communication system in which Rgg and SHP take part are well understood. However, many other players remain unidentified, and the direct targets of the system, as well as its link to virulence, remain unclear. Here, we identified the different players

  14. Functional amyloid formation by Streptococcus mutans

    Science.gov (United States)

    Oli, M. W.; Otoo, H. N.; Crowley, P. J.; Heim, K. P.; Nascimento, M. M.; Ramsook, C. B.; Lipke, P. N.

    2012-01-01

    Dental caries is a common infectious disease associated with acidogenic and aciduric bacteria, including Streptococcus mutans. Organisms that cause cavities form recalcitrant biofilms, generate acids from dietary sugars and tolerate acid end products. It has recently been recognized that micro-organisms can produce functional amyloids that are integral to biofilm development. We now show that the S. mutans cell-surface-localized adhesin P1 (antigen I/II, PAc) is an amyloid-forming protein. This conclusion is based on the defining properties of amyloids, including binding by the amyloidophilic dyes Congo red (CR) and Thioflavin T (ThT), visualization of amyloid fibres by transmission electron microscopy and the green birefringent properties of CR-stained protein aggregates when viewed under cross-polarized light. We provide evidence that amyloid is present in human dental plaque and is produced by both laboratory strains and clinical isolates of S. mutans. We provide further evidence that amyloid formation is not limited to P1, since bacterial colonies without this adhesin demonstrate residual green birefringence. However, S. mutans lacking sortase, the transpeptidase enzyme that media