Susceptibility of 169 USA300 methicillin-resistant Staphylococcus aureus isolates to two copper-based biocides, CuAL42 and CuWB50.

Science.gov (United States)

Luna, Vicki Ann; Hall, Tony J; King, Debbie S; Cannons, Andrew C

2010-05-01

To test the activity of two copper-based biocides, CuAL42 and CuWB50, and benzalkonium chloride against 169 isolates of methicillin-resistant Staphylococcus aureus (MRSA) pulsotype USA300, a virulent, multiply resistant, widespread clone in the USA. Tests including MIC, MBC and time-kill studies were performed multiple times. The MIC range, MIC(50) and MIC(90) (0.59-18.75, 4.69 and 4.69 ppm, respectively) and the MBC range, MBC(50) and MBC(90) (1.17-18.75, 4.69 and 9.38 ppm, respectively) for CuAL42 were identical with those obtained with CuWB50, except that the MBC range for CuWB50 was wider (0.59-37.5 ppm). In time-kill studies, a 6 log(10) reduction of cfu was achieved within 1 h (150 ppm) and 0.5 h (300 ppm) for CuAL42, and 1.5 h (150 ppm) and 0.75 h (300 ppm) for CuWB50. Both copper-based biocides can effectively kill USA300 MRSA and may facilitate the eradication of the organism from healthcare settings.

Aislamientos de Staphylococcus aureus sensibles a meticilina relacionados genéticamente con el clon USA300, ¿origen de los aislamientos SARM de genotipo comunitario en Colombia?

Directory of Open Access Journals (Sweden)

Javier Antonio Escobar-Pérez

2014-04-01

Full Text Available Introducción. USA300 es un linaje genético que se encuentra en aislamientos de Staphylococcus aureus sensibles (SASM y resistentes a meticilina (SARM. Actualmente, en Colombia las infecciones por SARM en hospitales y en la comunidad son causadas principalmente por un clon con genotipo comunitario (SARM-GC relacionado genéticamente con el clon USA300. El origen de esta variante es aún desconocido. Objetivo. Identificar y caracterizar aislamientos de S. aureus resistentes y sensibles a meticilina con el fin de aportar información para establecer un posible origen de los aislamientos SARM-GC en Colombia. Materiales y métodos. Se realizó una caracterización de aislamientos SASM relacionados con el clon USA300 detectados a partir de un análisis de 184 aislamientos de S. aureus (90 SARM y 94 SASM causantes de infecciones. La relación genética de los aislamientos se determinó por electroforesis en gel de campo pulsado (PFGE, tipificación de secuencias multilocus (MLST y tipificación del gen de la proteína A (spa. Resultados. De los 184 aislamientos, 27 (14,7 % presentaron características moleculares y relación genética con el clon USA300, y de ellos, 18 fueron SARM y nueve fueron SASM. Todos los aislamientos SARM relacionados con este clon albergaban un casete estafilocócico cromosómico mec (SCCmec IVc (3.1.2. En ningún aislamiento SASM se detectaron secuencias remanentes de SCCmec o una duplicación del sitio attB que evidenciaran la pérdida del casete. Conclusión. El origen de los aislamientos SARM-GC en Colombia probablemente se encuentre en la diseminación de clones SASM relacionados con el clon USA300 que adquirieron el SCCmec IVc posteriormente.

A horizontally gene transferred copper resistance locus confers hyper‐resistance to antibacterial copper toxicity and enables survival of community acquired methicillin resistant Staphylococcus aureus USA300 in macrophages

Science.gov (United States)

Purves, Joanne; Thomas, Jamie; Riboldi, Gustavo P.; Zapotoczna, Marta; Tarrant, Emma; Andrew, Peter W.; Londoño, Alejandra; Planet, Paul J.; Geoghegan, Joan A.; Waldron, Kevin J.

2018-01-01

Summary Excess copper is highly toxic and forms part of the host innate immune system's antibacterial arsenal, accumulating at sites of infection and acting within macrophages to kill engulfed pathogens. We show for the first time that a novel, horizontally gene transferred copper resistance locus (copXL), uniquely associated with the SCCmec elements of the highly virulent, epidemic, community acquired methicillin resistant Staphylococcus aureus (CA‐MRSA) USA300, confers copper hyper‐resistance. These genes are additional to existing core genome copper resistance mechanisms, and are not found in typical S. aureus lineages, but are increasingly identified in emerging pathogenic isolates. Our data show that CopX, a putative P1B‐3‐ATPase efflux transporter, and CopL, a novel lipoprotein, confer copper hyper‐resistance compared to typical S. aureus strains. The copXL genes form an operon that is tightly repressed in low copper environments by the copper regulator CsoR. Significantly, CopX and CopL are important for S. aureus USA300 intracellular survival within macrophages. Therefore, the emergence of new S. aureus clones with the copXL locus has significant implications for public health because these genes confer increased resistance to antibacterial copper toxicity, enhancing bacterial fitness by altering S. aureus interaction with innate immunity. PMID:29521441

First report of Panton–Valentine leukocidin-positive methicillin-susceptible Staphylococcus aureus ST88 harbouring ΦSa2usa isolated from refractory breast abscesses in Japan

Directory of Open Access Journals (Sweden)

A. Togashi

2016-09-01

Full Text Available A methicillin-susceptible Staphylococcus aureus with Panton–Valentine leukocidin (PVL genes was isolated from refractory breast abscesses of 12-year-old girl in Japan, and classified into ST88, spa-t1245 and coa-IIIa. This strain harboured PVL phage ΦSa2usa, which is usually found in ST8 community-acquired methicillin-resistant S. aureus clone USA300.

Community-associated methicillin-resistant Staphylococcus aureus causing chronic pneumonia.

Science.gov (United States)

Enayet, Iram; Nazeri, Ali; Johnson, Leonard B; Riederer, Kathleen; Pawlak, Joan; Saravolatz, Louis D

2006-04-01

A young woman presented with pneumonia of a 3-month duration with predominantly nodular pulmonary infiltrates. Methicillin-resistant Staphylococcus aureus was identified in multiple cultures of sputum specimens. According to findings of pulsed-field gel electrophoresis, the isolate was identical to USA 300 and carried a type IV Staphylococcus cassette chromosome mec type IV gene and the genes for Panton-Valentine leukocidin.

Role of lipase from community-associated methicillin-resistant Staphylococcus aureus strain USA300 in hydrolyzing triglycerides into growth-inhibitory free fatty acids.

Science.gov (United States)

Cadieux, Brigitte; Vijayakumaran, Vithooshan; Bernards, Mark A; McGavin, Martin J; Heinrichs, David E

2014-12-01

Part of the human host innate immune response involves the secretion of bactericidal lipids on the skin and delivery of triglycerides into abscesses to control invading pathogens. Two Staphylococcus aureus lipases, named SAL1 and SAL2, were identified in the community-associated methicillin-resistant S. aureus strain USA300, which, presumably, are produced and function to degrade triglycerides to release free fatty acids. We show that the SAL2 lipase is one of the most abundant proteins secreted by USA300 and is proteolytically processed from the 72-kDa proSAL2 to the 44-kDa mature SAL2 by the metalloprotease aureolysin. We show that spent culture supernatants had lipase activity on both short- and long-chain fatty acid substrates and that deletion of gehB, encoding SAL2, resulted in the complete loss of these activities. With the use of gas chromatography-mass spectrometry, we show that SAL2 hydrolyzed trilinolein to linoleic acid, a fatty acid with known antistaphylococcal properties. When added to cultures of USA300, trilinolein and, to a lesser extent, triolein inhibited growth in a SAL2-dependent manner. This effect was shown to be due to the enzymatic activity of SAL2 on these triglycerides, since the catalytically inactive SAL2 Ser412Ala mutant was incapable of hydrolyzing the triglycerides or yielding delayed growth in their presence. Overall, these results reveal that SAL2 hydrolyzes triglycerides of both short- and long-chain fatty acids and that the released free fatty acids have the potential to cause significant delays in growth, depending on the chemical nature of the free fatty acid. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Thioridazine Induces Major Changes in Global Gene Expression and Cell Wall Composition in Methicillin-Resistant Staphylococcus aureus USA300

DEFF Research Database (Denmark)

Thorsing, Mette; Klitgaard, Janne Kudsk; Atilano, Magda L.

2013-01-01

and the transcriptomic response of S. aureus to known inhibitors of cell wall synthesis suggests that TDZ disturbs PGN biosynthesis at a stage that precedes transpeptidation by penicillin-binding proteins (PBPs). In support of this notion, dramatic changes in the muropeptide profile of USA300 were observed following....... In the present study, we have examined the effect of a subinhibitory concentration of TDZ on antimicrobial resistance, the global transcriptome, and the cell wall composition of MRSA USA300. We show that TDZ is able to sensitize the bacteria to several classes of antimicrobials targeting the late stages...... a major impact on the cell wall biosynthesis pathway in S. aureus and provides new insights into how MRSA may be sensitized towards β-lactam antibiotics....

Complete genome sequence of community-associated methicillin-resistant Staphylococcus aureus (strain USA400-0051, a prototype of the USA400 clone

Directory of Open Access Journals (Sweden)

Marina Farrel Côrtes

Full Text Available Staphylococcus aureus subsp. aureus, commonly referred as S. aureus, is an important bacterial pathogen frequently involved in hospital- and community-acquired infections in humans, ranging from skin infections to more severe diseases such as pneumonia, bacteraemia, endocarditis, osteomyelitis, and disseminated infections. Here, we report the complete closed genome sequence of a community-acquired methicillin-resistant S. aureus strain, USA400-0051, which is a prototype of the USA400 clone.

Norlichexanthone Reduces Virulence Gene Expression and Biofilm Formation in Staphylococcus aureus

DEFF Research Database (Denmark)

Baldry, Mara; Nielsen, Anita; Bojer, Martin S.

2016-01-01

Staphylococcus aureus is a serious human pathogen and antibiotic resistant, community-associated strains, such as the methicillin resistant S. aureus (MRSA) strain USA300, continue to spread. To avoid resistance, anti-virulence therapy has been proposed where toxicity is targeted rather than...... viability. Previously we have shown that norlichexanthone, a small non-reduced tricyclic polyketide produced by fungi and lichens, reduces expression of hla encoding α-hemolysin as well as the regulatory RNAIII of the agr quorum sensing system in S. aureus 8325-4. The aim of the present study was to further...... SaeRS system. Our data show that norlichexanthone treatment reduces expression of key virulence factors in CA-MRSA strain USA300 via AgrA binding and represses biofilm formation....

Monoclonal antibodies protect from Staphylococcal Enterotoxin K (SEK) induced toxic shock and sepsis by USA300 Staphylococcus aureus.

Science.gov (United States)

Aguilar, Jorge L; Varshney, Avanish K; Pechuan, Ximo; Dutta, Kaushik; Nosanchuk, Joshua D; Fries, Bettina C

2017-08-18

Staphylococcus aureus is a leading infectious cause of life-threatening disease in humans, yet there is currently no vaccine to combat this bacterium. The pathogenesis of S. aureus is mediated by a diverse array of protein toxins including a large family of secreted pyrogenic superantigens. Neutralization of superantigens, including SEB and TSST-1, has proven to be protective in several animal models of toxic shock and sepsis. We demonstrate, for the first time, that a far more prevalent staphylococcal superantigen, SEK, can also induce lethal shock in mice. Additionally, we describe monoclonal antibodies (mAbs) that inhibit SEK-induced mitogenicity as well as protect against SEK-induced lethality, and enhance survival from S. aureus septicemia in murine models. MAb-4G3 (IgG2b), mAb-5G2 (IgG1), and mAb-9H2 (IgG1), all inhibit SEK-induced proliferation and cytokine production of human immune cells. We then demonstrate that passive immunization with a combination of mAb-4G3 and mAb-5G4, 2 mAbs that do not compete for epitope(s) on SEK, significantly enhance survival in a murine model of SEK-induced toxic shock (p = 0.006). In the setting of sepsis, passive immunization with this combination of mAbs also significantly enhances survival in mice after challenge with CA-MRSA strain USA300 (p = 0.03). Furthermore, septic mice that received mAb treatment in conjunction with vancomycin exhibit less morbidity than mice treated with vancomycin alone. Taken together, these findings suggest that the contribution of SEK to S. aureus pathogenesis may be greater than previously appreciated, and that adjunctive therapy with passive immunotherapy against SEs may be beneficial.

Hospital Epidemiology of Methicillin-Resistant Staphylococcus aureus in a Tertiary Care Hospital in Moshi, Tanzania, as Determined by Whole Genome Sequencing

DEFF Research Database (Denmark)

Kumburu, Happiness H.; Sonda, Tolbert; Leekitcharoenphon, Pimlapas

2018-01-01

Objective. To determine molecular epidemiology of methicillin-resistant S. aureus in Tanzania using whole genome sequencing. Methods. DNA from 33 Staphylococcus species was recovered from subcultured archived Staphylococcus isolates. Whole genome sequencing was performed on IlluminaMiseq using...... among the 30 S. aureus isolates, with ST-8 (n = seven, 23%) being the most common. Gene detection in S. aureus stains were as follows: mecA, 10 (33.3%); pvl, 5 (16.7%); tst, 2 (6.7%). The SNP difference among the six Tanzanian ST-8MRSA isolates ranged from 24 to 196 SNPs and from 16 to 446 SNPs when...... using the USA300_FPR3757 or the USA500 2395 as a reference, respectively. The mutation rate was 1.38 x 10(-11) SNPs/site/year or 1.4 x 10(-6) SNPs/site/year as estimated by USA300 FPR3757 or the USA500 2395, respectively. Conclusion. S. aureus isolates causing infections in hospitalized patients...

Subtle genetic changes enhance virulence of methicillin resistant and sensitive Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Hawes Alicia C

2007-11-01

Full Text Available Abstract Background Community acquired (CA methicillin-resistant Staphylococcus aureus (MRSA increasingly causes disease worldwide. USA300 has emerged as the predominant clone causing superficial and invasive infections in children and adults in the USA. Epidemiological studies suggest that USA300 is more virulent than other CA-MRSA. The genetic determinants that render virulence and dominance to USA300 remain unclear. Results We sequenced the genomes of two pediatric USA300 isolates: one CA-MRSA and one CA-methicillin susceptible (MSSA, isolated at Texas Children's Hospital in Houston. DNA sequencing was performed by Sanger dideoxy whole genome shotgun (WGS and 454 Life Sciences pyrosequencing strategies. The sequence of the USA300 MRSA strain was rigorously annotated. In USA300-MRSA 2658 chromosomal open reading frames were predicted and 3.1 and 27 kilobase (kb plasmids were identified. USA300-MSSA contained a 20 kb plasmid with some homology to the 27 kb plasmid found in USA300-MRSA. Two regions found in US300-MRSA were absent in USA300-MSSA. One of these carried the arginine deiminase operon that appears to have been acquired from S. epidermidis. The USA300 sequence was aligned with other sequenced S. aureus genomes and regions unique to USA300 MRSA were identified. Conclusion USA300-MRSA is highly similar to other MRSA strains based on whole genome alignments and gene content, indicating that the differences in pathogenesis are due to subtle changes rather than to large-scale acquisition of virulence factor genes. The USA300 Houston isolate differs from another sequenced USA300 strain isolate, derived from a patient in San Francisco, in plasmid content and a number of sequence polymorphisms. Such differences will provide new insights into the evolution of pathogens.

Antibiotic sensitivity pattern of Staphylococcus aureus from clinical

African Journals Online (AJOL)

raoul

2011-01-26

Jan 26, 2011 ... Key words: Staphylococcus aureus, antibiotic sensitivity, Nigeria, Kano ... infection have an increased colonization risks [8]. ... confirmed Staphylococcus aureus isolates was prepared in peptone water to ... 5 g methicillin discs (oxoid, USA) were aseptically placed on the surface of the inoculated plates and ...

Antimicrobial blue light inactivation of Methicillin-resistant Staphylococcus aureus

Science.gov (United States)

Wang, Yucheng; Dai, Tianhong; Gu, Ying

2016-10-01

Background: With the increasing emergence of multidrug-resistant (MDR) bacterial strains, there is a pressing need for the development of alternative treatment for infections. Antimicrobial blue light (aBL) has provided a simple and effective approach. Methods: We first investigated the effectiveness of aBL (415 nm) inactivation of USA300 LAClux (a communityacquired Methicillin-resistant Staphylococcus aureus strain) both in the planktonic and biofilm forms. The survival of the bacteria in suspensions was determined by serial dilution and that of the biofilm-embedded bacteria was determined by bioluminescence quantification. Using a mouse model of thermal burn infected with USA300 LAClux, we further assessed the effectiveness of aBL for treating localized infections. Bioluminescence imaging was performed to monitor in real time bacterial viability in vivo. Results: In vitro study showed that, for the planktonic counterpart of the bacteria or the 24-h-old biofilms, an irradiance of 55 mW/cm2 for 60 min resulted in a 4.61 log10 or 2.56 log10 inactivation, respectively. In vivo study using infected mouse burns demonstrated that a 2.56-log10 inactivation was achieved after 100-mW/cm2 irradiation for 62 min. Conclusions: aBL is a potential alternative approach for treating Methicillin-resistant Staphylococcus aureus infections.

Local circulating clones of Staphylococcus aureus in Ecuador.

Science.gov (United States)

Zurita, Jeannete; Barba, Pedro; Ortega-Paredes, David; Mora, Marcelo; Rivadeneira, Sebastián

The spread of pandemic Staphylococcus aureus clones, mainly methicillin-resistant S. aureus (MRSA), must be kept under surveillance to assemble an accurate, local epidemiological analysis. In Ecuador, the prevalence of the USA300 Latin American variant clone (USA300-LV) is well known; however, there is little information about other circulating clones. The aim of this work was to identify the sequence types (ST) using a Multiple-Locus Variable number tandem repeat Analysis 14-locus genotyping approach. We analyzed 132 S. aureus strains that were recovered from 2005 to 2013 and isolated in several clinical settings in Quito, Ecuador. MRSA isolates composed 46.97% (62/132) of the study population. Within MRSA, 37 isolates were related to the USA300-LV clone (ST8-MRSA-IV, Panton-Valentine Leukocidin [PVL] +) and 10 were related to the Brazilian clone (ST239-MRSA-III, PVL-). Additionally, two isolates (ST5-MRSA-II, PVL-) were related to the New York/Japan clone. One isolate was related to the Pediatric clone (ST5-MRSA-IV, PVL-), one isolate (ST45-MRSA-II, PVL-) was related to the USA600 clone, and one (ST22-MRSA-IV, PVL-) was related to the epidemic UK-EMRSA-15 clone. Moreover, the most prevalent MSSA sequence types were ST8 (11 isolates), ST45 (8 isolates), ST30 (8 isolates), ST5 (7 isolates) and ST22 (6 isolates). Additionally, we found one isolate that was related to the livestock associated S. aureus clone ST398. We conclude that in addition to the high prevalence of clone LV-ST8-MRSA-IV, other epidemic clones are circulating in Quito, such as the Brazilian, Pediatric and New York/Japan clones. The USA600 and UK-EMRSA-15 clones, which were not previously described in Ecuador, were also found. Moreover, we found evidence of the presence of the livestock associated clone ST398 in a hospital environment. Copyright © 2016 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

Identification and characterization of the multidrug resistance gene cfr in a Panton-Valentine leukocidin-positive sequence type 8 methicillin-resistant Staphylococcus aureus IVa (USA300) isolate.

LENUS (Irish Health Repository)

Shore, Anna C

2010-12-01

The staphylococcal cfr gene mediates resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A, a phenotype that has been termed PhLOPS(A). The cfr gene has mainly been associated with coagulase-negative staphylococcal isolates from animals, and only a few cfr-positive methicillin-resistant Staphylococcus aureus (MRSA) isolates have been described so far. This study reports the first description of a cfr-positive MRSA isolate (M05\\/0060) belonging to the pandemic Panton-Valentine leukocidin (PVL)-positive sequence type 8 MRSA IVa\\/USA300 (ST8-MRSA-IVa\\/USA300) clone. The cfr gene was detected in M05\\/0060 using a DNA microarray which was used to screen PVL-positive MRSA isolates for the presence of virulence genes, typing markers, and antimicrobial resistance genes. Antimicrobial susceptibility testing revealed that M05\\/0060 exhibited the cfr-associated resistance phenotype. Molecular analysis identified the presence of cfr and a second phenicol resistance gene, fexA, on a novel 45-kb conjugative plasmid, which was designated pSCFS7. Within pSCFS7, a DNA segment consisting of cfr, a truncated copy of insertion sequence IS21-558, and a region with homology to the DNA invertase gene bin3 of transposon Tn552 from Bacillus mycoides was integrated into the transposase gene tnpB of the fexA-carrying transposon Tn558. The emergence of a multidrug-resistant cfr-positive variant of ST8-MRSA-IVa\\/USA300 is alarming and requires ongoing surveillance. Moreover, the identification of a novel conjugative plasmid carrying the cfr gene indicates the ability of cfr to spread to other MRSA strains.

Genomic Characterization of USA300 Methicillin-Resistant Staphylococcus aureus (MRSA) to Evaluate Intraclass Transmission and Recurrence of Skin and Soft Tissue Infection (SSTI) Among High-Risk Military Trainees.

Science.gov (United States)

Millar, Eugene V; Rice, Gregory K; Elassal, Emad M; Schlett, Carey D; Bennett, Jason W; Redden, Cassie L; Mor, Deepika; Law, Natasha N; Tribble, David R; Hamilton, Theron; Ellis, Michael W; Bishop-Lilly, Kimberly A

2017-08-01

Military trainees are at increased risk for methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI). Whole genome sequencing (WGS) can refine our understanding of MRSA transmission and microevolution in congregate settings. We conducted a prospective case-control study of SSTI among US Army infantry trainees at Fort Benning, Georgia, from July 2012 to December 2014. We identified clusters of USA300 MRSA SSTI within select training classes and performed WGS on clinical isolates. We then linked genomic, phylogenetic, epidemiologic, and clinical data in order to evaluate intra- and interclass disease transmission. Furthermore, among cases of recurrent MRSA SSTI, we evaluated the intrahost relatedness of infecting strains. Nine training classes with ≥5 cases of USA300 MRSA SSTI were selected. Eighty USA300 MRSA clinical isolates from 74 trainees, 6 (8.1%) of whom had recurrent infection, were subjected to WGS. We identified 2719 single nucleotide variants (SNVs). The overall median (range) SNV difference between isolates was 173 (1-339). Intraclass median SNV differences ranged from 23 to 245. Two phylogenetic clusters were suggestive of interclass MRSA transmission. One of these clusters stemmed from 2 classes that were separated by a 13-month period but housed in the same barracks. Among trainees with recurrent MRSA SSTI, the intrahost median SNV difference was 7.5 (1-48). Application of WGS revealed intra- and interclass transmission of MRSA among military trainees. An interclass cluster between 2 noncontemporaneous classes suggests a long-term reservoir for MRSA in this setting. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Discriminatory Indices of Typing Methods for Epidemiologic Analysis of Contemporary Staphylococcus aureus Strains.

Science.gov (United States)

Rodriguez, Marcela; Hogan, Patrick G; Satola, Sarah W; Crispell, Emily; Wylie, Todd; Gao, Hongyu; Sodergren, Erica; Weinstock, George M; Burnham, Carey-Ann D; Fritz, Stephanie A

2015-09-01

Historically, a number of typing methods have been evaluated for Staphylococcus aureus strain characterization. The emergence of contemporary strains of community-associated S. aureus, and the ensuing epidemic with a predominant strain type (USA300), necessitates re-evaluation of the discriminatory power of these typing methods for discerning molecular epidemiology and transmission dynamics, essential to investigations of hospital and community outbreaks. We compared the discriminatory index of 5 typing methods for contemporary S. aureus strain characterization. Children presenting to St. Louis Children's Hospital and community pediatric practices in St. Louis, Missouri (MO), with community-associated S. aureus infections were enrolled. Repetitive sequence-based PCR (repPCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), staphylococcal protein A (spa), and staphylococcal cassette chromosome (SCC) mec typing were performed on 200 S. aureus isolates. The discriminatory index of each method was calculated using the standard formula for this metric, where a value of 1 is highly discriminatory and a value of 0 is not discriminatory. Overall, we identified 26 distinct strain types by repPCR, 17 strain types by PFGE, 30 strain types by MLST, 68 strain types by spa typing, and 5 strain types by SCCmec typing. RepPCR had the highest discriminatory index (D) of all methods (D = 0.88), followed by spa typing (D = 0.87), MLST (D = 0.84), PFGE (D = 0.76), and SCCmec typing (D = 0.60). The method with the highest D among MRSA isolates was repPCR (D = 0.64) followed by spa typing (D = 0.45) and MLST (D = 0.44). The method with the highest D among MSSA isolates was spa typing (D = 0.98), followed by MLST (D = 0.93), repPCR (D = 0.92), and PFGE (D = 0.89). Among isolates designated USA300 by PFGE, repPCR was most discriminatory, with 10 distinct strain types identified (D = 0.63). We identified 45

Comparative Efficacy of Ceftaroline with Linezolid against Staphylococcus Aureus and Methicillin Resistant Staphylococcus Aureus

International Nuclear Information System (INIS)

Hafeez, A.; Munir, T.; Rehman, S.; Najeeb, S.; Gilani, M.; Latif, M.; Ansari, M.; Saad, N.

2015-01-01

Objective:To compare the in vitro antimicrobial efficacy of ceftaroline with linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. Study Design: Quasi-experimental study. Place and Duration of Study: Microbiology Department, Army Medical College, Rawalpindi, from January to December 2013. Methodology: Clinical samples from respiratory tract, blood, pus and various catheter tips routinely received in the Department of Microbiology, Army Medical College, Rawalpindi were innoculated on blood and MacConkey agar. Staphylococcus aureus was identified by colony morphology, Gram reaction, catalase test and coagulase test. Methicillin resistant Staphylococcus aureus detection was done by modified Kirby Bauer disc diffusion method using cefoxitin disc (30g) and the isolates were considered methicillin resistant if the zone of inhibition around cefoxitin disc was /sup 2/ 21 mm. Bacterial suspensions of 56 Staphylococcus aureus isolates and 50 MRSA isolates were prepared, which were standardized equal to 0.5 McFarland's turbidity standard and inoculated on Mueller-Hinton agar plates followed by application of ceftaroline and linezolid disc (Oxoid, UK), according to manufacturer's instructions. The plates were then incubated at 37 Degree C aerobically for 18 - 24 hours. Diameters of inhibition zone were measured and interpretated as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Out of 106 isolates all of the 56 Staphylococcus aureus (100%) were sensitive to ceftaroline and linezolid. However, out of 50 methicillin resistant Staphylococcus aureus, 48 (96%) were sensitive to ceftaroline whereas, 49 (98%) were sensitive to linezolid. Conclusion: Ceftaroline is equally effective as linezolid against Staphylococcus aureus and methicillin resistant Staphylococcus aureus. (author)

Staphylococcus aureus Esx Factors Control Human Dendritic Cell Functions Conditioning Th1/Th17 Response

Directory of Open Access Journals (Sweden)

Melania Cruciani

2017-07-01

Full Text Available The opportunistic pathogen Staphylococcus aureus (S. aureus is a major cause of nosocomial- and community-acquired infections. In addition, many antibiotic-resistant strains are emerging worldwide, thus, there is an urgent unmet need to pinpoint novel therapeutic and prophylactic strategies. In the present study, we characterized the impact of infection with the pandemic methicillin-resistant USA300 S. aureus strain on human primary dendritic cells (DC, key initiators and regulators of immune responses. In particular, among staphylococcal virulence factors, the function of EsxA and EsxB, two small acidic dimeric proteins secreted by the type VII-like secretion system Ess (ESAT-6-like secretion system, was investigated in human DC setting. A comparative analysis of bacterial entry, replication rate as well as DC maturation, apoptosis, signaling pathway activation and cytokine production was performed by using wild type (wt USA300 and three isogenic mutants carrying the deletion of esxA (ΔesxA, esxB (ΔesxB, or both genes (ΔesxAB. The S. aureus mutant lacking only the EsxA protein (ΔesxA stimulated a stronger pro-apoptotic phenotype in infected DC as compared to wt USA300, ΔesxAB, and ΔesxB strains. When the mutant carrying the esxB deletion (ΔesxB was analyzed, a higher production of both regulatory and pro-inflammatory mediators was found in the infected DC with respect to those challenged with the wt counterpart and the other esx mutants. In accordance with these data, supernatant derived from ΔesxB-infected DC promoted a stronger release of both IFN-γ and IL-17 from CD4+ T cells as compared with those conditioned with supernatants derived from wild type USA300-, ΔesxAB-, and ΔesxA-infected cultures. Although, the interaction of S. aureus with human DC is not yet fully understood, our data suggest that both cytokine production and apoptotic process are modulated by Esx factors, thus indicating a possible role of these proteins in the

The impact of CodY on virulence determinant production in community-associated methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Rivera, Frances E; Miller, Halie K; Kolar, Stacey L; Stevens, Stanley M; Shaw, Lindsey N

2012-01-01

Staphylococcus aureus is a leading human pathogen of both hospital and community-associated diseases worldwide. This organism causes a wealth of infections within the human host as a result of the vast arsenal of toxins encoded within its genome. Previous transcriptomic studies have shown that toxin production in S. aureus can be strongly impacted by the negative regulator CodY. CodY acts by directly, and indirectly (via Agr), repressing toxin production during times of plentiful nutrition. In this study, we use iTRAQ-based proteomics for the first time to study virulence determinant production in S. aureus, so as to correlate transcriptional observations with actual changes in protein synthesis. Using a codY mutant in the epidemic CA-MRSA clone USA300 we demonstrate that deletion of this transcription factor results in a major upregulation of toxin synthesis in both post-exponential and stationary growth. Specifically, we observe hyper-production of secreted proteases, leukocidins and hemolysins in both growth phases in the USA300 codY mutant. Our findings demonstrate the power of mass spectrometry-based quantitative proteomics for studying toxin production in S. aureus, and the importance of CodY to this central process in disease causation and infection. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design of two molecular methodologies for the rapid identification of Colombian community-acquired methicillin-resistant Staphylococcus aureus isolates

OpenAIRE

Escobar, Javier Antonio; Gómez, Ingrid Tatiana; Murillo, Martha Johanna; Castro, Betsy Esperanza; Chavarro, Bibiana; Márquez, Ricaurte Alejandro; Vanegas, Natasha

2012-01-01

Introduction. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are found with increasing the frequency, both in healthy individuals in the community and in hospitalized patients. In Colombia and the Andean region, CA-MRSA isolates have a genetic background that is related to the pandemic USA300 clone. Objective. Two molecular methods are designed and standardized for the rapid differentiation of Colombian community-acquired and hospital-acquired methicillin-...

Staphylococcus aureus Central Nervous System Infections in Children.

Science.gov (United States)

Vallejo, Jesus G; Cain, Alexandra N; Mason, Edward O; Kaplan, Sheldon L; Hultén, Kristina G

2017-10-01

Central nervous system (CNS) infections caused by Staphylococcus aureus are uncommon in pediatric patients. We review the epidemiology, clinical features and treatment in 68 patients with a S. aureus CNS infection evaluated at Texas Children's Hospital. Cases of CNS infection in children with positive cerebrospinal fluid cultures or spinal epidural abscess (SEA) for S. aureus at Texas Children's Hospital from 2001 to 2013 were reviewed. Seventy cases of S. aureus CNS infection occurred in 68 patients. Forty-nine cases (70%) were secondary to a CNS device, 5 (7.1%) were postoperative meningitis, 9 (12.8%) were hematogenous meningitis and 7 (10%) were SEAs. Forty-seven (67.2%) were caused by methicillin-sensitive S. aureus (MSSA) and 23 (32.8%) by methicillin-resistant S. aureus (MRSA). Community-acquired infections were more often caused by MRSA that was clone USA300/pvl. Most patients were treated with nafcillin (MSSA) or vancomycin (MRSA) with or without rifampin. Among patients with MRSA infection, 50% had a serum vancomycin trough obtained with the median level being 10.6 μg/mL (range: 5.4-15.7 μg/mL). Only 1 death was associated with S. aureus infection. The epidemiology of invasive of S. aureus infections continues to evolve with MSSA accounting for most of the infections in this series. The majority of cases were associated with neurosurgical procedures; however, hematogenous S. aureus meningitis and SEA occurred as community-acquired infections in patients without predisposing factors. Patients with MRSA CNS infections had a favorable response to vancomycin, but the beneficial effect of combination therapy or targeting vancomycin trough concentrations of 15-20 μg/mL remains unclear.

Genetic pathway in acquisition and loss of vancomycin resistance in a methicillin resistant Staphylococcus aureus (MRSA strain of clonal type USA300.

Directory of Open Access Journals (Sweden)

Susana Gardete

2012-02-01

Full Text Available An isolate of the methicillin-resistant Staphylococcus aureus (MRSA clone USA300 with reduced susceptibility to vancomycin (SG-R (i.e, vancomycin-intermediate S. aureus, VISA and its susceptible "parental" strain (SG-S were recovered from a patient at the end and at the beginning of an unsuccessful vancomycin therapy. The VISA phenotype was unstable in vitro generating a susceptible revertant strain (SG-rev. The availability of these 3 isogenic strains allowed us to explore genetic correlates of antibiotic resistance as it emerged in vivo. Compared to the susceptible isolate, both the VISA and revertant strains carried the same point mutations in yycH, vraG, yvqF and lspA genes and a substantial deletion within an intergenic region. The revertant strain carried a single additional frameshift mutation in vraS which is part of two component regulatory system VraSR. VISA isolate SG-R showed complex alterations in phenotype: decreased susceptibility to other antibiotics, slow autolysis, abnormal cell division and increased thickness of cell wall. There was also altered expression of 239 genes including down-regulation of major virulence determinants. All phenotypic properties and gene expression profile returned to parental levels in the revertant strain. Introduction of wild type yvqF on a multicopy plasmid into the VISA strain caused loss of resistance along with loss of all the associated phenotypic changes. Introduction of the wild type vraSR into the revertant strain caused recovery of VISA type resistance. The yvqF/vraSR operon seems to function as an on/off switch: mutation in yvqF in strain SG-R turns on the vraSR system, which leads to increase in vancomycin resistance and down-regulation of virulence determinants. Mutation in vraS in the revertant strain turns off this regulatory system accompanied by loss of resistance and normal expression of virulence genes. Down-regulation of virulence genes may provide VISA strains with a "stealth

Molecular characterization of antimicrobial resistance genes against Staphylococcus aureus isolates from Trinidad and Tobago

Directory of Open Access Journals (Sweden)

Patrick E. Akpaka

2017-05-01

Full Text Available Summary: Staphylococcus aureus continues to pose major public health challenges in many areas because of antibiotic resistance problems. In the Caribbean, especially Trinidad and Tobago, the challenge is not different. This study was performed to evaluate the antimicrobial resistance gene prevalence among S. aureus isolates in Trinidad and Tobago.Standard and molecular microbiological methods, including the Microscan automated system, DNA microarray and multi locus sequence typing (MLST analysis, were performed on 309 clinical S. aureus isolates recovered from patients who were treated at three of the country's main health institutions.S. aureus exhibited susceptibilities ≥80% to eleven of the 19 antimicrobials tested against it, and these belong to the most commonly used and available antibiotics in the country. While the antibiotic to which it was most susceptible of the commonly used antibiotics was trimethoprim/sulfamethoxazole, the antibiotics to which it was least susceptible or most resistant to were ampicillin and penicillin. S. aureus isolates from the pediatric ward produced the greatest rate of susceptibility among the isolates recovered from patients admitted into hospitals, while isolates from Accident and Emergency rooms displayed the greatest susceptibilities among patients from the community.S. aureus isolates from the country did not harbor acquired resistant genes targeting clindamycin/macrolides (ermB, linezolid (cfr or vancomycin (vanA. The blaZ gene, which is the most common beta lactam (Penicillinase resistance mechanism for S. aureus, was observed in 88.7% of the methicillin susceptible S. aureus, while methicillin resistance mediated by the mec gene was present in 13.6%. Most of the resistance markers found in MRSA isolates were significantly associated with the ST239-MRSA-III strain in this study, and all isolates that belonged to the USA300 strain, which additionally encoded both the PVL gene and ACME cluster

Methicillin-resistant Staphylococcus aureus (MRSA)

Science.gov (United States)

Methicillin-resistant Staphylococcus aureus; Hospital-acquired MRSA (HA-MRSA); Staph - MRSA; Staphylococcal - MRSA ... Centers for Disease Control and Prevention website. Methicillin-resistant Staphylococcus aureus (MRSA). www.cdc.gov/mrsa/index.html . Updated ...

Antibiotic susceptibility pattern of staphylococcus aureus and methicillin-resistant staphylococcus aureus in a tertiary care hospital

Directory of Open Access Journals (Sweden)

CP Bhatt

2014-04-01

Full Text Available Background: Methicillin resistant Staphylococcus aureushas emerged as one of the most important nosocomial pathogens. It invokes a tremendous financial burden and enhanced morbidity and mortality due to difficult to treat systemic infections.Aim of this study was to determine antibiotic susceptibility pattern of Staphylococcus aureus and Methicillin resistant Staphylococcus aureus. Materials and Methods: Different clinical specimens were collected and processed for routine culture and antibiotic sensitivity test by standard microbiology techniques. Results: Out of 1173 samples received for microbiological examination, 100 were found to be S. aureus with 19% cases were Methicillin resistant Staphylococcus aureus (MRSA. Fourteen MRSA were found from inpatient and 5 were from outpatient. MRSA was found higher in female than male and maximum number (31.5% was found in age group 0-10 years. Staphylococcus aureus was 100% sensitive to Vancomycin followed by Amikacin (90%, Gentamycin (83%, and tetracycline (81%. On urine isolates Nitrofurantoin(91.6% was drug of choice. All the isolates were resistant to Penicillin G. In case of Methicillin resistant Staphylococcus aureus showed 100% sensitive to Vancomycin followed by Amikacin (84.2%, Tetracycline (63.1%, Ciprofloxacin (42% and Gentamycin (36.8%. Among urine isolates Nitrofutantoin showed 87.5% sensitive followed by Norfloxacin (75%. Conclusion: Methicillin resistant Staphylococcus aureus was found 19% of Staphylococcus aureus isolates. It was most common in females, hospitalized patients and young age group. Vancomycin seems to be drug of choice followed by Amikacin. It would be helpful to formulating and monitoring the antibiotic policy and ensure proper empiric treatment. DOI: http://dx.doi.org/10.3126/jpn.v4i7.10297 Journal of Pathology of Nepal (2014 Vol. 4, 548-551   

METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS (MRSA ...

African Journals Online (AJOL)

Nosocomial infections caused by methicillin-resistant strains of Staphylococcus aureus often pose therapeutic dilemma to the clinicians because of the multi resistant nature of these strains of Staphylococcus aureus. Outbreaks of both nosocomial and community acquired infections are also frequent and difficult to control.

Staphylococcus aureus colonization of healthy military service members in the United States and Afghanistan.

Science.gov (United States)

Vento, Todd J; Calvano, Tatjana P; Cole, David W; Mende, Katrin; Rini, Elizabeth A; Tully, Charla C; Landrum, Michael L; Zera, Wendy; Guymon, Charles H; Yu, Xin; Beckius, Miriam L; Cheatle, Kristelle A; Murray, Clinton K

2013-07-16

Staphylococcus aureus [methicillin-resistant and methicillin-susceptible (MRSA/MSSA)] is a leading cause of infections in military personnel, but there are limited data regarding baseline colonization of individuals while deployed. We conducted a pilot study to screen non-deployed and deployed healthy military service members for MRSA/MSSA colonization at various anatomic sites and assessed isolates for molecular differences. Colonization point-prevalence of 101 military personnel in the US and 100 in Afghanistan was determined by swabbing 7 anatomic sites. US-based individuals had received no antibiotics within 30 days, and Afghanistan-deployed personnel were taking doxycycline for malaria prophylaxis. Isolates underwent identification and testing for antimicrobial resistance, virulence factors, and pulsed-field type (PFT). 4 individuals in the US (4 isolates- 3 oropharynx, 1 perirectal) and 4 in Afghanistan (6 isolates- 2 oropharynx, 2 nare, 1 hand, 1 foot) were colonized with MRSA. Among US-based personnel, 3 had USA300 (1 PVL+) and 1 USA700. Among Afghanistan-based personnel, 1 had USA300 (PVL+), 1 USA800 and 2 USA1000. MSSA was present in 40 (71 isolates-25 oropharynx, 15 nare) of the US-based and 32 (65 isolates- 16 oropharynx, 24 nare) of the Afghanistan-based individuals. 56 (79%) US and 41(63%) Afghanistan-based individuals had MSSA isolates recovered from extra-nare sites. The most common MSSA PFTs were USA200 (9 isolates) in the US and USA800 (7 isolates) in Afghanistan. MRSA/MSSA isolates were susceptible to doxycycline in all but 3 personnel (1 US, 2 Afghanistan; all were MSSA isolates that carried tetM). MRSA and MSSA colonization of military personnel was not associated with deployment status or doxycycline exposure. Higher S. aureus oropharynx colonization rates were observed and may warrant changes in decolonization practices.

MRSA and multidrug-resistant Staphylococcus aureus in U.S. retail meats, 2010-2011.

Science.gov (United States)

Ge, Beilei; Mukherjee, Sampa; Hsu, Chih-Hao; Davis, Johnnie A; Tran, Thu Thuy T; Yang, Qianru; Abbott, Jason W; Ayers, Sherry L; Young, Shenia R; Crarey, Emily T; Womack, Niketta A; Zhao, Shaohua; McDermott, Patrick F

2017-04-01

Methicillin-resistant Staphylococcus aureus (MRSA) has been detected in retail meats, although large-scale studies are scarce. We conducted a one-year survey in 2010-2011 within the framework of the National Antimicrobial Resistance Monitoring System. Among 3520 retail meats collected from eight U.S. states, 982 (27.9%) contained S. aureus and 66 (1.9%) were positive for MRSA. Approximately 10.4% (107/1032) of S. aureus isolates, including 37.2% (29/78) of MRSA, were multidrug-resistant (MDRSA). Turkey had the highest MRSA prevalence (3.5%), followed by pork (1.9%), beef (1.7%), and chicken (0.3%). Whole-genome sequencing was performed for all 66 non-redundant MRSA. Among five multilocus sequence types identified, ST8 (72.7%) and ST5 (22.7%) were most common and livestock-associated MRSA ST398 was assigned to one pork isolate. Eleven spa types were represented, predominately t008 (43.9%) and t2031 (22.7%). All four types of meats harbored t008, whereas t2031 was recovered from turkey only. The majority of MRSA (84.8%) possessed SCCmec IV and 62.1% harbored Panton-Valentine leukocidin. Pulsed-field gel electrophoresis showed that all ST8 MRSA belonged to the predominant human epidemic clone USA300, and others included USA100 and USA200. We conclude that a diverse MRSA population was present in U.S. retail meats, albeit at low prevalence. Published by Elsevier Ltd.

Transcription and translation products of the cytolysin gene psm-mec on the mobile genetic element SCCmec regulate Staphylococcus aureus virulence.

Directory of Open Access Journals (Sweden)

Chikara Kaito

Full Text Available The F region downstream of the mecI gene in the SCCmec element in hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA contains two bidirectionally overlapping open reading frames (ORFs, the fudoh ORF and the psm-mec ORF. The psm-mec ORF encodes a cytolysin, phenol-soluble modulin (PSM-mec. Transformation of the F region into the Newman strain, which is a methicillin-sensitive S. aureus (MSSA strain, or into the MW2 (USA400 and FRP3757 (USA300 strains, which are community-acquired MRSA (CA-MRSA strains that lack the F region, attenuated their virulence in a mouse systemic infection model. Introducing the F region to these strains suppressed colony-spreading activity and PSMα production, and promoted biofilm formation. By producing mutations into the psm-mec ORF, we revealed that (i both the transcription and translation products of the psm-mec ORF suppressed colony-spreading activity and promoted biofilm formation; and (ii the transcription product of the psm-mec ORF, but not its translation product, decreased PSMα production. These findings suggest that both the psm-mec transcript, acting as a regulatory RNA, and the PSM-mec protein encoded by the gene on the mobile genetic element SCCmec regulate the virulence of Staphylococcus aureus.

[Carriage of Staphylococcus aureus among food service workers].

Science.gov (United States)

Alarcón-Lavín, María Paula; Oyarzo, Carolina; Escudero, Carlos; Cerda-Leal, Fabiola; Valenzuela, Francisco J

2017-12-01

Background Staphylococcus aureus produces 11 serotypes of endotoxins that may cause food poisoning. Aim To determine the prevalence of type A enterotoxigenic Staphylococcus aureus carriage among food service workers in Chillan, Chile. Material and Methods Pharyngeal swabs were obtained from 100 food service workers and were cultured in Agar plates. After identifying the presence of Staphylococcus aureus, DNA was extracted to identify type A toxin by conventional PCR. Results Thirty eight percent of samples were colonized with Staphylococcus aureus. Among these, 26% were toxin A producers. Conclusions Half of the sampled workers carried Staphylococcus aureus and a quarter of these produced type A enterotoxin.

Community-associated Methicillin-resistant Staphylococcus aureus Bacteremia and Endocarditis among HIV Patients: A cohort study

Directory of Open Access Journals (Sweden)

Stine Oscar C

2011-10-01

Full Text Available Abstract Background HIV patients are at increased risk of development of infections and infection-associated poor health outcomes. We aimed to 1 assess the prevalence of USA300 community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA among HIV-infected patients with S. aureus bloodstream infections and. 2 determine risk factors for infective endocarditis and in-hospital mortality among patients in this population. Methods All adult HIV-infected patients with documented S. aureus bacteremia admitted to the University of Maryland Medical Center between January 1, 2003 and December 31, 2005 were included. CA-MRSA was defined as a USA300 MRSA isolate with the MBQBLO spa-type motif and positive for both the arginine catabolic mobile element and Panton-Valentin Leukocidin. Risk factors for S. aureus-associated infective endocarditis and mortality were determined using logistic regression to calculate odds ratios (OR and 95% confidence intervals (CI. Potential risk factors included demographic variables, comorbid illnesses, and intravenous drug use. Results Among 131 episodes of S. aureus bacteremia, 85 (66% were MRSA of which 47 (54% were CA-MRSA. Sixty-three patients (48% developed endocarditis and 10 patients (8% died in the hospital on the index admission Patients with CA-MRSA were significantly more likely to develop endocarditis (OR = 2.73, 95% CI = 1.30, 5.71. No other variables including comorbid conditions, current receipt of antiretroviral therapy, pre-culture severity of illness, or CD4 count were significantly associated with endocarditis and none were associated with in-hospital mortality. Conclusions CA-MRSA was significantly associated with an increased incidence of endocarditis in this cohort of HIV patients with MRSA bacteremia. In populations such as these, in which the prevalence of intravenous drug use and probability of endocarditis are both high, efforts must be made for early detection, which may improve

The dominant Australian community-acquired methicillin-resistant Staphylococcus aureus clone ST93-IV [2B] is highly virulent and genetically distinct.

Directory of Open Access Journals (Sweden)

Kyra Y L Chua

Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA USA300 has spread rapidly across North America, and CA-MRSA is also increasing in Australia. However, the dominant Australian CA-MRSA strain, ST93-IV [2B] appears distantly related to USA300 despite strikingly similar clinical and epidemiological profiles. Here, we compared the virulence of a recent Australian ST93 isolate (JKD6159 to other MRSA, including USA300, and found that JKD6159 was the most virulent in a mouse skin infection model. We fully sequenced the genome of JKD6159 and confirmed that JKD6159 is a distinct clone with 7616 single nucleotide polymorphisms (SNPs distinguishing this strain from all other S. aureus genomes. Despite its high virulence there were surprisingly few virulence determinants. However, genes encoding α-hemolysin, Panton-Valentine leukocidin (PVL and α-type phenol soluble modulins were present. Genome comparisons revealed 32 additional CDS in JKD6159 but none appeared to encode new virulence factors, suggesting that this clone's enhanced pathogenicity could lie within subtler genome changes, such as SNPs within regulatory genes. To investigate the role of accessory genome elements in CA-MRSA epidemiology, we next sequenced three additional Australian non-ST93 CA-MRSA strains and compared them with JKD6159, 19 completed S. aureus genomes and 59 additional S. aureus genomes for which unassembled genome sequence data was publicly available (82 genomes in total. These comparisons showed that despite its distinctive genotype, JKD6159 and other CA-MRSA clones (including USA300 share a conserved repertoire of three notable accessory elements (SSCmecIV, PVL prophage, and pMW2. This study demonstrates that the genetically distinct ST93 CA-MRSA from Australia is highly virulent. Our comparisons of geographically and genetically diverse CA-MRSA genomes suggest that apparent convergent evolution in CA-MRSA may be better explained by the rapid

Staphylococcus aureus and hand eczema severity

DEFF Research Database (Denmark)

Haslund, P; Bangsgaard, N; Jarløv, J O

2009-01-01

BACKGROUND: The role of bacterial infections in hand eczema (HE) remains to be assessed. OBJECTIVES: To determine the prevalence of Staphylococcus aureus in patients with HE compared with controls, and to relate presence of S. aureus, subtypes and toxin production to severity of HE. METHODS......: Bacterial swabs were taken at three different visits from the hand and nose in 50 patients with HE and 50 controls. Staphylococcus aureus was subtyped by spa typing and assigned to clonal complexes (CCs), and isolates were tested for exotoxin-producing S. aureus strains. The Hand Eczema Severity Index...... and in the nose in all cases, and between visits in 90% of cases. Ten different CC types were identified, no association with severity was found, and toxin-producing strains were not found more frequently in patients with HE than in controls. CONCLUSIONS: Staphylococcus aureus was present on hands in almost half...

Colonization of nursing professionals by Staphylococcus aureus La colonización de los profesionales de enfermería por Staphylococcus aureus A colonização dos profissionais de enfermagem por Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Josely Pinto de Moura

2011-04-01

Full Text Available This cross-sectional study aimed to investigate the presence of Staphylococcus aureus in the saliva of the nursing team of a teaching hospital in the interior of São Paulo State. Three saliva samples were collected from 351 individuals with an interval of two months between each collection. All ethical aspects were considered. In 867 (82.3% cultures there was no identification of Staphylococcus aureus in the saliva, in 88 (17.7% cultures Staphylococcus aureus was isolated, 26 (2.5% of which were resistant to methicillin. The prevalence of professionals colonized by Staphylococcus aureus was 41.0% (144/351, of which 7.1% (25/351 were characterized as methicillin-resistant Staphylococcus aureus. Transient carriers represented 81.2% and persistent carriers 18.8%. Resistance to mupirocin was 73.1% of MRSA and 9.3% of MSSA. The results demonstrate that it is the nurse and nursing technician that are the professional categories most susceptible to MRSA. Broader discussion on the thematic and interventions are needed.Se trata de un estudio transversal que tuvo como objetivo investigar la presencia de Staphylococcus aureus en la saliva del equipo de enfermería de un hospital escuela del interior del estado de Sao Paulo. Fueron recolectadas tres muestras de saliva de 351 individuos con intervalo de dos meses. Todos los aspectos éticos fueron contemplados. En 867 (82,3% culturas no hubo identificación de Staphylococcus aureus en la saliva, en 88 (17,7% culturas fue aislado Staphylococcus aureus, siendo 26 (2,5% resistentes a la meticilina. La prevalencia de profesionales colonizados por Staphylococcus aureus fue de 41,0% (144/351, de los cuales 7,1% (25/351 fueron caracterizados como Staphylococcus aureus resistentes a la meticilina. Los portadores transitorios representaron 81,2% y los persistentes 18,8%. La resistencia a la mupirocina fue de 73,1% entre los resistentes a la meticilina y 9,3% en los sensibles a la meticilina. Los resultados

One-year mortality in coagulase-negative Staphylococcus and Staphylococcus aureus infective endocarditis

DEFF Research Database (Denmark)

Rasmussen, Rasmus V; Snygg-Martin, Ulrika; Olaison, Lars

2009-01-01

The aim of this study was to investigate in-hospital mortality and 12-month mortality in patients with coagulase-negative Staphylococcus (CoNS) compared to Staphylococcus aureus (S. aureus) infective endocarditis (IE). We used a prospective cohort study of 66 consecutive CoNS and 170 S. aureus IE...

Glycerol monolaurate and dodecylglycerol effects on Staphylococcus aureus and toxic shock syndrome toxin-1 in vitro and in vivo.

Directory of Open Access Journals (Sweden)

Ying-Chi Lin

2009-10-01

Full Text Available Glycerol monolaurate (GML, a 12 carbon fatty acid monoester, inhibits Staphylococcus aureus growth and exotoxin production, but is degraded by S. aureus lipase. Therefore, dodecylglycerol (DDG, a 12 carbon fatty acid monoether, was compared in vitro and in vivo to GML for its effects on S. aureus growth, exotoxin production, and stability.Antimicrobial effects of GML and DDG (0 to 500 microg/ml on 54 clinical isolates of S. aureus, including pulsed-field gel electrophoresis (PFGE types USA200, USA300, and USA400, were determined in vitro. A rabbit Wiffle ball infection model assessed GML and DDG (1 mg/ml instilled into the Wiffle ball every other day effects on S. aureus (MN8 growth (inoculum 3x10(8 CFU/ml, toxic shock syndrome toxin-1 (TSST-1 production, tumor necrosis factor-alpha (TNF-alpha concentrations and mortality over 7 days. DDG (50 and 100 microg/ml inhibited S. aureus growth in vitro more effectively than GML (p<0.01 and was stable to lipase degradation. Unlike GML, DDG inhibition of TSST-1 was dependent on S. aureus growth. GML-treated (4 of 5; 80% and DDG-treated rabbits (2 of 5; 40% survived after 7 days. Control rabbits (5 of 5; 100% succumbed by day 4. GML suppressed TNF-alpha at the infection site on day 7; however, DDG did not (<10 ng/ml versus 80 ng/ml, respectively.These data suggest that DDG was stable to S. aureus lipase and inhibited S. aureus growth at lower concentrations than GML in vitro. However, in vivo GML was more effective than DDG by reducing mortality, and suppressing TNF-alpha, S. aureus growth and exotoxin production, which may reduce toxic shock syndrome. GML is proposed as a more effective anti-staphylococcal topical anti-infective candidate than DDG, despite its potential degradation by S. aureus lipase.

Antibiotic susceptibility of Staphylococcus aureus in suppurative ...

African Journals Online (AJOL)

1299, p<0.05) and Methicillin resistance was confirmed by PCR. Conclusion: Staphylococcus aureus is highly prevalent and more resistant in inpatients. There is a higher risk of acquiring drug resistant staphylococcus aureus infection in ...

Staphylococcus aureus detection in the mouth of housekeepers Detección de Staphylococcus aureus en la boca de trabajadores de la limpieza hospitalaria Detecção de Staphylococcus aureus na boca de trabalhadores da limpeza hospitalar

Directory of Open Access Journals (Sweden)

Elaine Drehmer de Almeida Cruz

2011-02-01

Full Text Available This study assessed the prevalence of colonization by Staphylococcus aureus in hospital housekeepers, and their knowledge and beliefs regarding this problem. Three saliva samples were collected and a questionnaire regarding knowledge and beliefs was applied. Of the 92 workers, 63 (68.5% participated in the study; 20 were not and 43 were colonized; 13 by methicillin resistant Staphylococcus aureus and 30 by methicillin sensitive Staphylococcus aureus. Persistent carrier status of methicillin resistant Staphylococcus aureus was detected in 15.4% of cases. Low knowledge and perception of occupational risk were observed. The mouth was identified as an important reservoir of methicillin resistant Staphylococcus aureus. Analyzing knowledge and beliefs, as well as the state of carrier, is an important strategy to be added to educational actions for the prevention of workers' colonization.Este estudio evaluó la prevalencia de la colonización por Staphylococcus aureus en trabajadores de limpieza hospitalaria, y su conocimiento y creencias acerca de la problemática. Fueron recolectadas tres muestras de saliva y aplicado un cuestionario referente al conocimiento y creencias. De 92 trabajadores, 63 (68,5% participaron del estudio; 20 se presentaron no colonizados y 43 colonizados; 13 para Staphylococcus aureus resistente a la meticilina y 30 para Staphylococcus aureus sensibles a la meticilina. El estado de portador persistente por Staphylococcus aureus resistente a la meticilina fue detectado en 15,4% de los casos. Bajo conocimiento y percepción del riesgo ocupacional fueron observados. La boca fue identificada como importante reservatorio de Staphylococcus aureus resistente a la meticilina. Analizar el conocimiento y creencias juntamente con la investigación del estado de portador es una importante estrategia a ser agregada a las acciones educativas para la prevención de la colonización de trabajadores.Este estudo avaliou a prevalência da coloniza

Community-associated methicillin-resistant Staphylococcus aureus infection in Portugal

Directory of Open Access Journals (Sweden)

R. Nazareth

2012-01-01

Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA has recently emerged as a cause of community-acquired infections among individuals without risk factors. Community-associated MRSA (CA-MRSA appears to be more virulent, causing superficial mild skin and soft tissue infections to severe necrotizing fasciitis, and in rare cases, pneumonia.Community-associated MRSA was first reported in Australia in the early 80s, after almost two decades in the USA, and then in several countries in Europe, Asia and South America. No data exists in Portugal.We report the first case of CA-MRSA infection in Portugal, in a young adult with severe necrotizing pneumonia, complicated with bilateral empyema and respiratory failure. Resumo: Recentemente assistiu-se à emergência de infeções na comunidade por Staphylococcus aureus meticilina-resistente (MRSA em indivíduos sem fatores de risco. O MRSA associado à comunidade (CA-MRSA parece ser mais virulento, causando desde infeções superficiais da pele e tecidos moles até fasceíte necrosante e, raramente, pneumonia.O CA-MRSA foi inicialmente identificado na Austrália no início da década de 80 e, após cerca de duas décadas, surgiu nos EUA e em vários países da Europa, Ásia e América do Sul. Não existe informação disponível acerca da prevalência em Portugal.Os autores reportam o primeiro caso de infeção por CA-MRSA em Portugal, num adulto jovem com pneumonia necrotizante grave complicada por empiema bilateral e insuficiência respiratória. Keywords: Community-associated, MRSA, Staphylococcus aureus, Necrotizing pneumonia, Empyema, Palavras-chave: comunidade associada, MRSA, Staphylococcus aureus, pneumonia necrosante, empiema

Staphylococcus aureus and community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in and around therapeutic whirlpools in college athletic training rooms.

Science.gov (United States)

Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A

2015-04-01

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Cross-sectional study. National Collegiate Athletic Association Division I university. Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F(2,238) = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses.

The agr inhibitors solonamide B and analogues alter immune responses to Staphylococccus aureus but do not exhibit adverse effects on immune cell functions

DEFF Research Database (Denmark)

Baldry, Mara; Kitir, Betül; Frøkiær, Hanne

2016-01-01

Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed as an alte......Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed...... as an alternative approach to treat multi-drug resistant pathogens. One interesting anti-virulence target is the agr quorum-sensing system, which regulates virulence of CA-MRSA in response to agr-encoded autoinducing peptides. Agr regulation confines exotoxin production to the stationary growth phase...

Methicillin resistant Staphylococcus aureus in Ethiopia: a meta-analysis.

Science.gov (United States)

Eshetie, Setegn; Tarekegn, Fentahun; Moges, Feleke; Amsalu, Anteneh; Birhan, Wubet; Huruy, Kahsay

2016-11-21

The burden of methicillin resistant Staphylococcus aureus is a major public health concern worldwide; however the overall epidemiology of multidrug resistant strains is neither coordinated nor harmonized, particularly in developing countries including Ethiopia. Therefore, the aim of this meta-analysis was to assess the burden of methicillin resistant Staphylococcos aureus and its antibiotic resistance pattern in Ethiopia at large. PubMed, Google Scholar, and lancet databases were searched and a total of 20 studies have been selected for meta-analysis. Six authors have independently extracts data on the prevalence of methicillin resistant Staphylococcus aureus among clinical isolates of Staphylococcus aureus. Statistical analysis was achieved by using Open meta-analyst (version 3.13) and Comprehensive meta-analysis (version 3.3) softwares. The overall prevalence of methicillin resistant Staphylococcus aureus and its antibiotic resistance pattern were pooled by using the forest plot, table and figure with 95% CI. The pooled prevalence of methicillin resistant Staphylococcus aureus was 32.5% (95% CI, 24.1 to 40.9%). Moreover, methicillin resistant Staphylococcus aureus strains were found to be highly resistant to penicillin, ampicillin, erythromycin, and amoxicillin, with a pooled resistance ratio of 99.1, 98.1, 97.2 and 97.1%, respectively. On the other hand, comparably low levels of resistance ratio were noted to vancomycin, 5.3%. The overall burden of methicillin resistant Staphylococcus aureus is considerably high, besides these strains showed extreme resistance to penicillin, ampicillin, erythromycin and amoxicillin. In principle, appropriate use of antibiotics, applying safety precautions are the key to reduce the spread of multidrug resistant strains, methicillin resistant Staphylococcus aureus in particular.

New antimicrobial combinations: substituted chalcones- oxacillin against methicillin resistant Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Juan Manuel Talia

2011-06-01

Full Text Available Staphylococcus aureus, the most virulent Staphylococcus species, is also the prevalent pathogen isolated from hospitalized patients and the second most common from patients in outpatient settings. In general, bacteria have the genetic ability to transmit and acquire resistance to drugs, which are utilized as therapeutic agents. Related studies of antimicrobial activity indicate that crude extracts containing flavonoids, triterpenes and steroids have showed significative activity against several Staphylococcus aureus strains. Combination effects between flavonoids and antibiotics also have been reported. The aim of the present work was to investigate in vitro synergism between several chalcones substituted in combination with oxacillin, an antibiotic used conventionally against S. aureus ATCC 43 300 that is resistant to meticillin, using the kinetic turbidimetric method developed earlier. The results were satisfactory for all assayed combinations and in accordance with the mechanism of bacteriostatic inhibition previously proposed, except for 2´,4´-dihydroxy-3´-methoxychalcone - oxacillin. The best combination was 2´,3´-dihydroxychalcone - oxacillin (MIC: 11.2 μg/mL. Further investigations are needed to characterize the interaction mechanism with antibiotics. Thus, chalcones - oxacillin combination could lead to the development of new antibiotics against methicillin resistant S. aureus infection.

Panton-Valentine leukocidin is not the primary determinant of outcome for Staphylococcus aureus skin infections: evaluation from the CANVAS studies.

Directory of Open Access Journals (Sweden)

Amy Tong

Full Text Available The impact of Panton-Valentine leukocidin (PVL on the severity of complicated skin and skin structure infections (cSSSI caused by Staphylococcus aureus is controversial. We evaluated potential associations between clinical outcome and PVL presence in both methicillin-resistant S. aureus (MRSA and methicillin-susceptible S. aureus (MSSA isolates from patients enrolled in two large, multinational phase three clinical trials assessing ceftaroline fosamil for the treatment of cSSSI (the CANVAS 1 and 2 programs. Isolates from all microbiologically evaluable patients with monomicrobial MRSA or MSSA infections (n = 473 were genotyped by PCR for pvl and underwent pulsed-field gel electrophoresis (PFGE. Genes encoding pvl were present in 266/473 (56.2% isolates. Infections caused by pvl-positive S. aureus were associated with younger patient age, North American acquisition, and presence of major abscesses (P<0.001 for each. Cure rates of patients infected with pvl-positive and pvl-negative S. aureus were similar overall (93.6% versus 92.8%; P = 0.72, and within MRSA-infected (94.5% vs. 93.1%; P = 0.67 and MSSA-infected patients (92.2% vs. 92.7%; P = 1.00. This finding persisted after adjustment for multiple patient characteristics. Outcomes were also similar when USA300 PVL+ and non-USA300 PVL+ infections were compared. The results of this contemporary, international study suggest that pvl presence was not the primary determinant of outcome in patients with cSSSI due to either MRSA or MSSA.

Staphylococcus aureus and Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) in and Around Therapeutic Whirlpools in College Athletic Training Rooms

Science.gov (United States)

Kahanov, Leamor; Kim, Young Kyun; Eberman, Lindsey; Dannelly, Kathleen; Kaur, Haninder; Ramalinga, A.

2015-01-01

Context: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a leading cause of skin and soft tissue infection in the nonhospitalized community. Care of the athletes in athletic training rooms is specifically designed with equipment tailored to the health care needs of the athletes, yet recent studies indicate that CA-MRSA is still prevalent in athletic facilities and that cleaning methods may not be optimal. Objective: To investigate the prevalence of Staphylococcus aureus and CA-MRSA in and around whirlpools in the athletic training room. Design: Cross-sectional study. Setting: National Collegiate Athletic Association Division I university. Patients or Other Participants: Student-athletes (n = 109) consisting of 46 men (42%) and 63 women (58%) representing 6 sports. Main Outcome Measure(s): Presence of MRSA and Staphylococcus aureus in and around the whirlpool structures relative to sport and number of athletes using the whirlpools. Results: We identified Staphylococcus aureus in 22% (n = 52/240) of the samples and MRSA in 0.8% (n = 2/240). A statistically significant difference existed between the number of athletes using the whirlpool and the presence of Staphylococcus aureus in and around the whirlpools (F2,238 = 2.445, P = .007). However, Staphylococcus aureus was identified regardless of whether multiple athletes used a whirlpool or no athletes used a whirlpool. We did not identify a relationship between the number of athletes who used a whirlpool and Staphylococcus aureus or MRSA density (P = .134). Conclusions: Staphylococcus aureus and MRSA were identified in and around the whirlpools. Transmission of the bacteria can be reduced by following the cleaning and disinfecting protocols recommended by the Centers for Disease Control and Prevention. Athletic trainers should use disinfectants registered by the Environmental Protection Agency to sanitize all whirlpools between uses. PMID:25710853

Genome-wide Annotation, Identification, and Global Transcriptomic Analysis of Regulatory or Small RNA Gene Expression in Staphylococcus aureus.

Science.gov (United States)

Carroll, Ronan K; Weiss, Andy; Broach, William H; Wiemels, Richard E; Mogen, Austin B; Rice, Kelly C; Shaw, Lindsey N

2016-02-09

In Staphylococcus aureus, hundreds of small regulatory or small RNAs (sRNAs) have been identified, yet this class of molecule remains poorly understood and severely understudied. sRNA genes are typically absent from genome annotation files, and as a consequence, their existence is often overlooked, particularly in global transcriptomic studies. To facilitate improved detection and analysis of sRNAs in S. aureus, we generated updated GenBank files for three commonly used S. aureus strains (MRSA252, NCTC 8325, and USA300), in which we added annotations for >260 previously identified sRNAs. These files, the first to include genome-wide annotation of sRNAs in S. aureus, were then used as a foundation to identify novel sRNAs in the community-associated methicillin-resistant strain USA300. This analysis led to the discovery of 39 previously unidentified sRNAs. Investigating the genomic loci of the newly identified sRNAs revealed a surprising degree of inconsistency in genome annotation in S. aureus, which may be hindering the analysis and functional exploration of these elements. Finally, using our newly created annotation files as a reference, we perform a global analysis of sRNA gene expression in S. aureus and demonstrate that the newly identified tsr25 is the most highly upregulated sRNA in human serum. This study provides an invaluable resource to the S. aureus research community in the form of our newly generated annotation files, while at the same time presenting the first examination of differential sRNA expression in pathophysiologically relevant conditions. Despite a large number of studies identifying regulatory or small RNA (sRNA) genes in Staphylococcus aureus, their annotation is notably lacking in available genome files. In addition to this, there has been a considerable lack of cross-referencing in the wealth of studies identifying these elements, often leading to the same sRNA being identified multiple times and bearing multiple names. In this work

Prevalence of Methicillin-Resistant Staphylococcus aureus among ...

African Journals Online (AJOL)

Purpose: To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in apparently healthy ... treatment failures is vital. Keywords: Methicillin-resistant Staphylococcus aureus, Nasal swabs, Multidrug resistance, Rational .... defined as resistance to three or more classes of antibiotics other than the ...

The sensitivity status of community-acquired Staphylococcus aureus ...

African Journals Online (AJOL)

Community acquired Staphylococcus aureus was isolated from various infectious sites in two private laboratories in Kano-city, Nigeria. A total of 247 (11%) Staphylococcu aureus isolates were recovered from all infectious sites except cerebro-spinal fluid. The least Staphylococcus aureus isolates were found in urine ...

Communications of Staphylococcus aureus and non-aureus Staphylococcus species from bovine intramammary infections and teat apex colonization.

Science.gov (United States)

Mahmmod, Yasser S; Klaas, Ilka Christine; Svennesen, Line; Pedersen, Karl; Ingmer, Hanne

2018-05-16

The role of non-aureus staphylococci (NAS) in the risk of acquisition of intramammary infections with Staphylococcus aureus is vague and still under debate. The objectives of this study were to (1) investigate the distribution patterns of NAS species from milk and teat skin in dairy herds with automatic milking systems, and (2) examine if the isolated NAS influences the expression of S. aureus virulence factors controlled by the accessory gene regulator (agr) quorum sensing system. In 8 herds, 14 to 20 cows with elevated somatic cell count were randomly selected for teat skin swabbing and aseptic quarter foremilk samples from right hind and left front quarters. Teat skin swabs were collected using the modified wet-dry method and milk samples were taken aseptically for bacterial culture. Colonies from quarters with suspicion of having NAS in milk or teat skin samples (or both) were subjected to MALDI-TOF assay for species identification. To investigate the interaction between S. aureus and NAS, 81 isolates NAS were subjected to a qualitative β-galactosidase reporter plate assay. In total, 373 NAS isolates were identified representing 105 from milk and 268 from teat skin of 284 quarters (= 142 cows). Sixteen different NAS species were identified, 15 species from teat skin and 10 species from milk. The most prevalent NAS species identified from milk were Staphylococcus epidermidis (50%), Staphylococcus haemolyticus (15%), and Staphylococcus chromogenes (11%), accounting for 76%. Meanwhile, the most prevalent NAS species from teat skin were Staphylococcus equorum (43%), S. haemolyticus (16%), and Staphylococcus cohnii (14%), accounting for 73%. Using reporter gene fusions monitoring transcriptional activity of key virulence factors and regulators, we found that out of 81 supernatants of NAS isolates, 77% reduced expression of hla, encoding a-hemolysin, 70% reduced expression of RNAIII, the key effector molecule of agr, and 61% reduced expression of spa encoding

First report in South America of companion animal colonization by the USA1100 clone of community-acquired meticillin-resistant Staphylococcus aureus (ST30) and by the European clone of methicillin-resistant Staphylococcus pseudintermedius (ST71).

Science.gov (United States)

Quitoco, Isidório Mebinda Zuco; Ramundo, Mariana Severo; Silva-Carvalho, Maria Cícera; Souza, Raquel Rodrigues; Beltrame, Cristiana Ossaille; de Oliveira, Táya Figueiredo; Araújo, Rodrigo; Del Peloso, Pedro Fernandez; Coelho, Leonardo Rocchetto; Figueiredo, Agnes Marie Sá

2013-08-27

Methicillin-resistant staphylococci can colonize and cause diseases in companion animals. Unfortunately, few molecular studies have been carried out in Brazil and other countries with the aim of characterizing these isolates. Consequently, little is known about the potential role of companion animals in transmitting these resistant bacteria to humans. In this work we searched for mecA gene among Staphylococcus isolates obtained from nasal microbiota of 130 healthy dogs and cats attended in a veterinary clinic located in the west region of Rio de Janeiro. The isolates recovered were identified to the species level and characterized using molecular tools. A community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolate related to USA1100 (Southwest Pacific clone) and susceptible to all non-β-lactams was detected in a cat (1.7%, 1/60). Another coagulase-positive isolate harboring mecA was recovered from a dog (1.4%, 1/70) and identified as Staphylococcus pseudintermedius (MRSP) related to the European clone (ST71). The two isolates of Staphylococcus conhii subsp. urealyticus (1.4%, 1/70 dogs and 1.7%, 1/60 cats), similarly to the MRSP isolate, also presented high-level multiresistance. The majority of the methicillin-resistant coagulase-negative staphylococci recovered were Staphylococcus saprophyticus (5.7%, 4/70 dogs and 6.7%, 4/60 cats) and all clustered into the same PFGE type. This work demonstrates that mecA-harboring Staphylococcus isolates are common members of the nasal microbiota of the healthy companion animals studied (9.2%, 12/130 animals), including some high-level multiresistant isolates of S. pseudintermedius and S. conhii subsp. urealyticus. The detection, for the first time in South America, of USA1100-related CA-MRSA and of ST71 MRSP (European clone), colonizing companion animals, is of concern. Both S. pseudintermedius and S. aureus are important agents of infections for animals. The USA1100 CA-MRSA is a causative of severe and

Molecular epidemiology of community-onset methicillin-resistant Staphylococcus aureus infections in Israel.

Science.gov (United States)

Biber, A; Parizade, M; Taran, D; Jaber, H; Berla, E; Rubin, C; Rahav, G; Glikman, D; Regev-Yochay, G

2015-08-01

Data on community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) in Israel are scarce. The objective of this study was to characterize the major CA-MRSA clones in Israel. All clinical MRSA isolates detected in the community during a period of 2.5 years (2011-2013) from individuals insured by a major health maintenance organization in Israel were collected, with additional data from medical records. Antibiotic susceptibility patterns and staphylococcal chromosomal cassette mec (SCCmec) typing were determined. SCCmec IV and V isolates were further typed by pulsed-field gel electrophoresis (PFGE), spa typing, and detection of a panel of toxin genes. MRSA were detected in 280 patients, mostly from skin infections. Patients with SCCmec IV (n = 120, 43 %) were younger (p Israel, approximately 20 % are typical CA-MRSA clones, mainly USA300 and a local clone, t991.

Inhibition of Virulence Gene Expression in Staphylococcus aureus by Novel Depsipeptides from a Marine Photobacterium

Directory of Open Access Journals (Sweden)

Lone Gram

2011-12-01

Full Text Available During a global research expedition, more than five hundred marine bacterial strains capable of inhibiting the growth of pathogenic bacteria were collected. The purpose of the present study was to determine if these marine bacteria are also a source of compounds that interfere with the agr quorum sensing system that controls virulence gene expression in Staphylococcus aureus. Using a gene reporter fusion bioassay, we recorded agr interference as enhanced expression of spa, encoding Protein A, concomitantly with reduced expression of hla, encoding α-hemolysin, and rnaIII encoding RNAIII, the effector molecule of agr. A marine Photobacterium produced compounds interfering with agr in S. aureus strain 8325-4, and bioassay-guided fractionation of crude extracts led to the isolation of two novel cyclodepsipeptides, designated solonamide A and B. Northern blot analysis confirmed the agr interfering activity of pure solonamides in both S. aureus strain 8325-4 and the highly virulent, community-acquired strain USA300 (CA-MRSA. To our knowledge, this is the first report of inhibitors of the agr system by a marine bacterium.

Genetic Screen Reveals the Role of Purine Metabolism in Staphylococcus aureus Persistence to Rifampicin

Directory of Open Access Journals (Sweden)

Rebecca Yee

2015-12-01

Full Text Available Chronic infections with Staphylococcus aureus such as septicemia, osteomyelitis, endocarditis, and biofilm infections are difficult to treat because of persisters. Despite many efforts in understanding bacterial persistence, the mechanisms of persister formation in S. aureus remain elusive. Here, we performed a genome-wide screen of a transposon mutant library to study the molecular mechanisms involved in persistence of community-acquired S. aureus. Screening of the library for mutants defective in persistence or tolerance to rifampicin revealed many genes involved in metabolic pathways that are important for antibiotic persistence. In particular, the identified mutants belonged to metabolic pathways involved in carbohydrate, amino acid, lipid, vitamin and purine biosynthesis. Five mutants played a role in purine biosynthesis and two mutants, purB, an adenylosuccinate lyase, and purM, a phosphoribosylaminoimidazole synthetase, were selected for further confirmation. Mutants purB and purM showed defective persistence compared to the parental strain USA300 in multiple stress conditions including various antibiotics, low pH, and heat stress. The defect in persistence was restored by complementation with the wildtype purB and purM gene in the respective mutants. These findings provide new insights into the mechanisms of persistence in S. aureus and provide novel therapeutic targets for developing more effective treatment for persistent infections due to S. aureus.

Methicillin-resistant Staphylococcus aureus in palliative care: A prospective study of Methicillin-resistant Staphylococcus aureus prevalence in a hospital-based palliative care unit.

Science.gov (United States)

Schmalz, Oliver; Strapatsas, Tobias; Alefelder, Christof; Grebe, Scott Oliver

2016-07-01

Methicillin-resistant Staphylococcus aureus is a common organism in hospitals worldwide and is associated with morbidity and mortality. However, little is known about the prevalence in palliative care patients. Furthermore, there is no standardized screening protocol or treatment for patients for whom therapy concentrates on symptom control. Examining the prevalence of methicillin-resistant Staphylococcus aureus in palliative care patients as well as the level of morbidity and mortality. We performed a prospective study where methicillin-resistant Staphylococcus aureus screening was undertaken in 296 consecutive patients within 48 h after admission to our palliative care unit. Medical history was taken, clinical examination was performed, and the Karnofsky Performance Scale and Palliative Prognostic Score were determined. Prevalence of Methicillin-resistant Staphylococcus aureus was compared to data of general hospital patients. In total, 281 patients were included in the study having a mean age of 69.7 years (standard deviation = 12.9 years) and an average Karnofsky Performance Scale between 30% and 40%. The mean length of stay was 9.7 days (standard deviation = 7.6 days). A total of 24 patients were methicillin-resistant Staphylococcus aureus positive on the first swab. Median number of swabs was 2. All patients with a negative methicillin-resistant Staphylococcus aureus swab upon admission remained Methicillin-resistant Staphylococcus aureus negative in all subsequent swabs. Our study suggests that the prevalence of Methicillin-resistant Staphylococcus aureus among patients in an in-hospital palliative care unit is much higher than in other patient populations. © The Author(s) 2016.

Antimicrobial resistant coagulase positive Staphylococcus aureus ...

African Journals Online (AJOL)

ADEYEYE

S. aureus is associated with many clinical syndromes including tenosynovitis, omphalitis, femoral head necrosis, .... Markey, 2008) where occurrence of multidrug ... Staphylococcus aureus isolates from bovine mastitis in. Denmark. Veterinary.

Diseño de dos metodologías moleculares para la rápida identificación de aislamientos de Staphylococcus aureus resistente a meticilina asociados a la comunidad en Colombia

OpenAIRE

Javier Antonio Escobar; Ingrid Tatiana Gómez; Martha Johanna Murillo; Betsy Esperanza Castro; Bibiana Chavarro; Ricaurte Alejandro Márquez; Natasha Vanegas

2012-01-01

Introducción. Los aislamientos de Staphylococcus aureus resistente a la meticilina asociado a la comunidad (SARM-AC), están aumentando la frecuencia de infecciones en personas sanas de la comunidad y en pacientes hospitalizados. En Colombia y en la región andina estos aislamientos tienen un componente genético relacionado con el clon pandémico USA300. Objetivo. Diseñar y estandarizar dos metodologías para la diferenciación rápida de aislamientos colombianos de S. aureus resistente a la me...

PREVALENCIA DE Staphylococcus epidermidis Y Staphylococcus aureus EN PACIENTES CON CONJUNTIVITIS

Directory of Open Access Journals (Sweden)

P. Hernández-Rodríguez

2005-12-01

Full Text Available Con el fin de establecer la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, se evaluaron clínica y bacteriológicamente 131 pacientes con diagnóstico clínico presuntivo de conjuntivitis. A cada participante se le tomó muestra de secreción ocular, para la coloración de Gram y cultivo; además, se probó la susceptibilidad de los aislamientos frente a Oxacilina (Ox, Gentamicina (GM, Vancomicina (Va, Trimetoprim Sulfamethoxazole (SXT, Tetraciclina (Te, Cefalothin (CF, Ceftriaxone (CRO y Ciprofloxacina (CIP. El 53% de los cultivos bacteriológicos fueron positivos, donde el 87% de los aislamientos correspondieron a Gram positivos, siendo los más frecuentes Staphylococcus epidermidis (43%, Staphylococcus aureus (30%, Streptococcus sp. (15%, Enterococcus (7%, Corynebacterium sp. 5%. Se observó multirresistencia frente a 3 ó más antibióticos en S. epidermidis (44% y S.aureus (42%. La alta frecuencia de estos microorganismos y la multirresistencia encontrada en este estudio, determinan la importancia que tienen, como posibles patógenos oculares, y la necesidad de implementar las pruebas de susceptibilidad bacteriana en el ámbito oftalmológico. Este es el primer estudio publicado en Colombia sobre la prevalencia de Staphylococcus epidermidis y Staphylococcus aureus en pacientes con conjuntivitis, el cual seguramente originará la iniciación de posteriores investigaciones, encaminadas a determinar el verdadero papel de estos microorganismos, en el proceso infeccioso ocular.

Staphylococcus aureus hyaluronidase is a CodY-regulated virulence factor.

Science.gov (United States)

Ibberson, Carolyn B; Jones, Crystal L; Singh, Shweta; Wise, Matthew C; Hart, Mark E; Zurawski, Daniel V; Horswill, Alexander R

2014-10-01

Staphylococcus aureus is a Gram-positive pathogen that causes a diverse range of bacterial infections. Invasive S. aureus strains secrete an extensive arsenal of hemolysins, immunomodulators, and exoenzymes to cause disease. Our studies have focused on the secreted enzyme hyaluronidase (HysA), which cleaves the hyaluronic acid polymer at the β-1,4 glycosidic bond. In the study described in this report, we have investigated the regulation and contribution of this enzyme to S. aureus pathogenesis. Using the Nebraska Transposon Mutant Library (NTML), we identified eight insertions that modulate extracellular levels of HysA activity. Insertions in the sigB operon, as well as in genes encoding the global regulators SarA and CodY, significantly increased HysA protein levels and activity. By altering the availability of branched-chain amino acids, we further demonstrated CodY-dependent repression of HysA activity. Additionally, through mutation of the CodY binding box upstream of hysA, the repression of HysA production was lost, suggesting that CodY is a direct repressor of hysA expression. To determine whether HysA is a virulence factor, a ΔhysA mutant of a community-associated methicillin-resistant S. aureus (CA-MRSA) USA300 strain was constructed and found to be attenuated in a neutropenic, murine model of pulmonary infection. Mice infected with this mutant strain exhibited a 4-log-unit reduction in bacterial burden in their lungs, as well as reduced lung pathology and increased levels of pulmonary hyaluronic acid, compared to mice infected with the wild-type, parent strain. Taken together, these results indicate that S. aureus hyaluronidase is a CodY-regulated virulence factor. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Preclinical Efficacy of Clumping Factor A in Prevention of Staphylococcus aureus Infection

Directory of Open Access Journals (Sweden)

Xue Li

2016-02-01

Full Text Available Treatment of Staphylococcus aureus infections has become increasingly difficult because of the emergence of multidrug-resistant isolates. Development of a vaccine to prevent staphylococcal infections remains a priority. To determine whether clumping factor A (ClfA is a good target protein for inclusion in a multivalent vaccine, we evaluated its efficacy in a variety of relevant staphylococcal infection models, challenging with different S. aureus strains. ClfA adsorbed to Alhydrogel and mixed with Sigma Adjuvant System was more immunogenic and stimulated a more robust Th17 response than ClfA administered with alum alone. ClfA immunization induced the production of functional antibodies in rabbits and mice that blocked S. aureus binding to fibrinogen and were opsonic for S. aureus strains that produced little or no capsular polysaccharide. Mice immunized with ClfA showed a modest reduction in the bacterial burden recovered from subcutaneous abscesses provoked by S. aureus USA300 strain LAC. In addition, the ClfA vaccine reduced lethality in a sepsis model following challenge with strain Newman, but not ST80. Vaccination with ClfA did not protect against surgical wound infection, renal abscess formation, or bacteremia. Passive immunization with antibodies to ClfA did not protect against staphylococcal bacteremia in mice or catheter-induced endocarditis in rats. Some enhancement of bacteremia was observed by ClfA immunization or passive administration of ClfA antibodies when mice were challenged by the intraperitoneal route. Although rodent models of staphylococcal infection have their limitations, our data do not support the inclusion of ClfA in an S. aureus multivalent vaccine.

Preclinical Efficacy of Clumping Factor A in Prevention of Staphylococcus aureus Infection

Science.gov (United States)

Li, Xue; Wang, Xiaogang; Thompson, Christopher D.; Park, Saeyoung; Park, Wan Beom

2016-01-01

ABSTRACT Treatment of Staphylococcus aureus infections has become increasingly difficult because of the emergence of multidrug-resistant isolates. Development of a vaccine to prevent staphylococcal infections remains a priority. To determine whether clumping factor A (ClfA) is a good target protein for inclusion in a multivalent vaccine, we evaluated its efficacy in a variety of relevant staphylococcal infection models, challenging with different S. aureus strains. ClfA adsorbed to Alhydrogel and mixed with Sigma Adjuvant System was more immunogenic and stimulated a more robust Th17 response than ClfA administered with alum alone. ClfA immunization induced the production of functional antibodies in rabbits and mice that blocked S. aureus binding to fibrinogen and were opsonic for S. aureus strains that produced little or no capsular polysaccharide. Mice immunized with ClfA showed a modest reduction in the bacterial burden recovered from subcutaneous abscesses provoked by S. aureus USA300 strain LAC. In addition, the ClfA vaccine reduced lethality in a sepsis model following challenge with strain Newman, but not ST80. Vaccination with ClfA did not protect against surgical wound infection, renal abscess formation, or bacteremia. Passive immunization with antibodies to ClfA did not protect against staphylococcal bacteremia in mice or catheter-induced endocarditis in rats. Some enhancement of bacteremia was observed by ClfA immunization or passive administration of ClfA antibodies when mice were challenged by the intraperitoneal route. Although rodent models of staphylococcal infection have their limitations, our data do not support the inclusion of ClfA in an S. aureus multivalent vaccine. PMID:26838725

Pseudomonas aeruginosa induces pigment production and enhances virulence in a white phenotypic variant of Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Antonic V

2013-11-01

Full Text Available Vlado Antonic,1–3 Alexander Stojadinovic,3–5 Binxue Zhang,1–3 Mina J Izadjoo,1–3,5 Mohammad Alavi1–3 1Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA; 2Diagnostic and Translational Research Center, Gaithersburg, MD, USA; 3Combat Wound Initiative Program, Bethesda, MD, USA; 4Walter Reed National Military Medical Center, Bethesda, MD, USA; 5Uniformed Services University of the Health Sciences, Bethesda, MD, USA Abstract: Staphyloxanthin is a virulence factor which protects Staphylococcus aureus in stress conditions. We isolated two pigment variants of S. aureus and one strain of Pseudomonas aeruginosa from a single wound infection. S. aureus variants displayed white and yellow colony phenotypes. The sequence of the operons for staphyloxanthin synthesis indicated that coding and promoter regions were identical between the two pigment variants. Quorum sensing controls pigment synthesis in some bacteria. It is also shown that P. aeruginosa quorum-sensing molecules affect S. aureus transcription. We explored whether the co-infecting P. aeruginosa can affect pigment production in the white S. aureus variant. In co-culture experiments between the white variants and a selected number of Gram-positive and Gram-negative bacteria, only P. aeruginosa induced pigment production in the white variant. Gene expression analysis of the white variant did not indicate upregulation of the crtM and other genes known to be involved in pigment production (sigB, sarA, farnesyl pyrophosphate synthase gene [FPP-synthase], hfq. In contrast, transcription of the catalase gene was significantly upregulated after co-culture. P. aeruginosa-induced pigment synthesis and catalase upregulation correlated with increased resistance to polymyxin B, hydrogen peroxide, and the intracellular environment of macrophages. Our data indicate the presence of silent but functional staphyloxanthin synthesis machinery in a white phenotypic variant

Staphylococcus aureus bacteraemia in children: a formidable foe ...

African Journals Online (AJOL)

Staphylococcus aureus remains one of the most common causes of bacteraemia in children. In order to evade and overcome the immune responses of its host and any antimicrobial therapies aimed at destroying it, this organism, through various mechanisms, continues to evolve. Staphylococcus aureus bacteraemia is a ...

Prevalence and risk factors for Staphylococcus aureus and ...

African Journals Online (AJOL)

Prevalence and risk factors for Staphylococcus aureus and methicillin‑resistant Staphylococcus aureus nasal carriage inpatients in a tertiary care hospital's chest clinic in Turkey. ... of the participants and risk factors for carriage. Fisher's exact test, univariate and multivariate logistic regression analysis were used. A P < 0.05 ...

Identification of single nucleotide polymorphisms associated with hyperproduction of alpha-toxin in Staphylococcus aureus.

Directory of Open Access Journals (Sweden)

Xudong Liang

2011-04-01

Full Text Available The virulence factor α-toxin (hla is needed by Staphylococcus aureus in order to cause infections in both animals and humans. Although the complicated regulation of hla expression has been well studied in human S. aureus isolates, the mechanisms of of hla regulation in bovine S. aureus isolates remain undefined. In this study, we found that many bovine S. aureus isolates, including the RF122 strain, generate dramatic amounts of α-toxin in vitro compared with human clinical S. aureus isolates, including MRSA WCUH29 and MRSA USA300. To elucidate potential regulatory mechanisms, we analyzed the hla promoter regions and identified predominant single nucleotide polymorphisms (SNPs at positions -376, -483, and -484 from the start codon in α-toxin hyper-producing isolates. Using site-directed mutagenesis and hla promoter-gfp-luxABCDE dual reporter approaches, we demonstrated that the SNPs contribute to the differential control of hla expression among bovine and human S. aureus isolates. Using a DNA affinity assay, gel-shift assays and a null mutant, we identified and revealed that an hla positive regulator, SarZ, contributes to the involvement of the SNPs in mediating hla expression. In addition, we found that the bovine S. aureus isolate RF122 exhibits higher transcription levels of hla positive regulators, including agrA, saeR, arlR and sarZ, but a lower expression level of hla repressor rot compared to the human S. aureus isolate WCUH29. Our results indicate α-toxin hyperproduction in bovine S. aureus is a multifactorial process, influenced at both the genomic and transcriptional levels. Moreover, the identification of predominant SNPs in the hla promoter region may provide a novel method for genotyping the S. aureus isolates.

Transfer of Antibiotic Resistance in Staphylococcus aureus

DEFF Research Database (Denmark)

Haaber, Jakob; Penadés, José R; Ingmer, Hanne

2017-01-01

Staphylococcus aureus is a serious human pathogen with remarkable adaptive powers. Antibiotic-resistant clones rapidly emerge mainly by acquisition of antibiotic-resistance genes from other S. aureus strains or even from other genera. Transfer is mediated by a diverse complement of mobile genetic...... of plasmids that can be transferred by conjugation and the efficiency with which transduction occurs. Here, we review the main routes of antibiotic resistance gene transfer in S. aureus in the context of its biology as a human commensal and a life-threatening pathogen. Staphylococcus aureus cells...... are effective in exchanging mobile genetic elements, including antibiotic-resistance genes.During colonization or infection of host organisms, the exchange appears to be particularly effective.Bacteriophage-mediated transfer involves both transduction and autotransduction, which may enable lysogenic S. aureus...

Staphylococcus aureus and healthcare-associated infections

NARCIS (Netherlands)

Ekkelenkamp, M.B.

2011-01-01

Many medical procedures breach or suppress patients’ natural defences, leaving them vulnerable to infections which would not occur in healthy humans: “healthcare-associated infections”. Healthcare-associated infections caused by the bacterium Staphylococcus aureus (S. aureus) are probably the most

spa Typing and Multilocus Sequence Typing Show Comparable Performance in a Macroepidemiologic Study of Staphylococcus aureus in the United States.

Science.gov (United States)

O'Hara, F Patrick; Suaya, Jose A; Ray, G Thomas; Baxter, Roger; Brown, Megan L; Mera, Robertino M; Close, Nicole M; Thomas, Elizabeth; Amrine-Madsen, Heather

2016-01-01

A number of molecular typing methods have been developed for characterization of Staphylococcus aureus isolates. The utility of these systems depends on the nature of the investigation for which they are used. We compared two commonly used methods of molecular typing, multilocus sequence typing (MLST) (and its clustering algorithm, Based Upon Related Sequence Type [BURST]) with the staphylococcal protein A (spa) typing (and its clustering algorithm, Based Upon Repeat Pattern [BURP]), to assess the utility of these methods for macroepidemiology and evolutionary studies of S. aureus in the United States. We typed a total of 366 clinical isolates of S. aureus by these methods and evaluated indices of diversity and concordance values. Our results show that, when combined with the BURP clustering algorithm to delineate clonal lineages, spa typing produces results that are highly comparable with those produced by MLST/BURST. Therefore, spa typing is appropriate for use in macroepidemiology and evolutionary studies and, given its lower implementation cost, this method appears to be more efficient. The findings are robust and are consistent across different settings, patient ages, and specimen sources. Our results also support a model in which the methicillin-resistant S. aureus (MRSA) population in the United States comprises two major lineages (USA300 and USA100), which each consist of closely related variants.

Root cause analysis of methicillin resistant Staphylococcus aureus bacteraemia.

Science.gov (United States)

Aslam, Nadia; Mehdi, Naima; Izhar, Mateen

2015-10-01

To find the important risk factors and sources of bacteraemia in patients suffering from methicillin-resistant staphylococcus aureus bacteraemia. The descriptive study was carried out at Shaikh Zayed Hospital, Lahore, from October 2010 to August 2011. Blood cultures were processed to isolate methicillin-resistant staphylococcus aureus. A questionnaire was completed by the participating patients suffering from bacteraemia. Information about risk factors present at the time and risk factors that served as the source of bacteraemia were noted. Total 4058 blood cultures were processed and 669(16.5%) were positive. Of them, 194(29%) cultures were found to be positive for staphylococci. Out of these 194 blood cultures, coagulase-negative staphylococci were isolated from 117(60%), and 77(40%) were positive for S. aureus. Out of these 77 samples, 26(34%) were found to be methicillin-sensitive staphylococcus aureus and 51(66%) were methicillin-resistant staphylococcus aureus. The overall frequency of methicillin-resistant staphylococcus aureus was 1.25%; 7.62% out of positive blood culture; 26.28% out of total staphylococci; and 66% out of total S. aureus. As for the source of infection, central venous pressure line 11(21.6%), post-influenza pneumonia 9(17.6%), peripheral intravenous line 8(15.7%) and dialysis line 7(13.7%) were major reasons. Taking care of aseptic measures while insertion, frequent change and early removal of the central venous and dialysis lines is of critical significance.

Streptococcus pneumoniae eradicates preformed Staphylococcus aureus biofilms through a mechanism requiring physical contact

Directory of Open Access Journals (Sweden)

Faidad Khan

2016-09-01

Full Text Available Staphylococcus aureus (Sau strains are a main cause of disease, including nosocomial infections which have been linked to the production of biofilms and the propagation of antibiotic resistance strains such as methicillin-resistant Staphylococcus aureus (MRSA. A previous study found that Streptococcus pneumoniae (Spn strains kill planktonic cultures of Sau strains. In this work, we have further evaluated in detail the eradication of Sau biofilms and investigated ultrastructural interactions of the biofilmicidal effect. Spn strain D39, which produces the competence stimulating peptide 1 (CSP1, reduced Sau biofilms within 8 h of inoculation, while TIGR4, producing CSP2, eradicated Sau biofilms and planktonic cells within 4 h. Differences were not attributed to pherotypes as other Spn strains producing different pheromones eradicated Sau within 4 h. Experiments using Transwell devices, which physically separated both species growing in the same well, demonstrated that direct contact between Spn and Sau was required to efficiently eradicate Sau biofilms and biofilm-released planktonic cells. Physical contact-mediated killing of Sau was not related to production of hydrogen peroxide as an isogenic TIGR4spxB mutant eradicated Sau bacteria within 4 h. Confocal micrographs confirmed eradication of Sau biofilms by TIGR4 and allowed us to visualize ultrastructural point of contacts between Sau and Spn. A time-course study further demonstrated spatial colocalization of Spn chains and Sau tetrads as early as 30 min post-inoculation (Pearson’s coefficient >0.72. Finally, precolonized biofilms produced by Sau strain Newman, or MRSA strain USA300, were eradicated by mid-log phase cultures of washed TIGR4 bacteria within 2 h post-inoculation. In conclusion, Spn strains rapidly eradicate pre-colonized Sau aureus biofilms, including those formed by MRSA strains, by a mechanism(s requiring bacterium-bacterium contact, but independent from the production of

An Unexpected Location of the Arginine Catabolic Mobile Element (ACME) in a USA300-Related MRSA Strain

DEFF Research Database (Denmark)

Damkjær Bartels, Mette; Hansen, Lars H.; Boye, Kit

2011-01-01

In methicillin resistant Staphylococcus aureus (MRSA), the arginine catabolic mobile element (ACME) was initially described in USA300 (t008-ST8) where it is located downstream of the staphylococcal cassette chromosome mec (SCCmec). A common health-care associated MRSA in Copenhagen, Denmark (t024......-ST8) is clonally related to USA300 and is frequently PCR positive for the ACME specific arcA-gene. This study is the first to describe an ACME element upstream of the SCCmec in MRSA. By traditional SCCmec typing schemes, the SCCmec of t024-ST8 strain M1 carries SCCmec IVa, but full sequencing...... of SCCmec, M1 had two new DR between the orfX gene and the J3 region of the SCCmec. The region between the orfX DR (DR1) and DR2 contained the ccrAB4 genes. An ACME II-like element was located between DR2 and DR3. The entire 26,468 bp sequence between DR1 and DR3 was highly similar to parts of the ACME...

Participation of the arcRACME protein in self-activation of the arc operon located in the arginine catabolism mobile element in pandemic clone USA300.

Science.gov (United States)

Rozo, Zayda Lorena Corredor; Márquez-Ortiz, Ricaurte Alejandro; Castro, Betsy Esperanza; Gómez, Natasha Vanegas; Escobar-Pérez, Javier

2017-07-01

Staphylococcus aureus pandemic clone USA300 has, in addition to its constitutive arginine catabolism (arc) gene cluster, an arginine catabolism mobile element (ACME) carrying another such cluster, which gives this clone advantages in colonisation and infection. Gene arcR, which encodes an oxygen-sensitive transcriptional regulator, is inside ACME and downstream of the constitutive arc gene cluster, and this situation may have an impact on its activation. Different relative expression behaviours are proven here for arcRACME and the arcACME operon compared to the constitutive ones. We also show that the artificially expressed recombinant ArcRACME protein binds to the promoter region of the arcACME operon; this mechanism can be related to a positive feedback model, which may be responsible for increased anaerobic survival of the USA300 clone during infection-related processes.

Alpha-Toxin Promotes Mucosal Biofilm Formation by Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Michele J Anderson

2012-05-01

Full Text Available Staphylococcus aureus causes numerous diseases in humans ranging from the mild skin infections to serious, life-threatening, superantigen-mediated Toxic Shock Syndrome (TSS. S. aureus may also be asymptomatically carried in the anterior nares, vagina or on the skin, which serve as reservoirs for infection. Pulsed-field gel electrophoresis clonal type USA200 is the most widely disseminated colonizer and a major cause of TSS. Our prior studies indicated that α-toxin was a major epithelial proinflammatory exotoxin produced by TSS S. aureus USA200 isolates. It also facilitated the penetration of TSS Toxin-1 (TSST-1 across vaginal mucosa. However, the majority of menstrual TSS isolates produce low α-toxin due to a nonsense point mutation at codon 113, designated hly, suggesting mucosal adaptation. The aim of this study was to characterize the differences between TSS USA200 strains [high (hla+ and low (hly+ α-toxin producers] in their abilities to infect and disrupt vaginal mucosal tissue. A mucosal model was developed using ex vivo porcine vaginal mucosa, LIVE/DEAD® staining and confocal microscropy to characterize biofilm formation and tissue viability of TSS USA 200 isolates CDC587 and MN8, which contain the α-toxin pseudogene (hly, MNPE (hla+ and MNPE isogenic hla knockout (hlaKO. All TSS strains grew to similar bacterial densities (1-5 x 108 CFU on the mucosa and were proinflammatory over 3 days. However, MNPE formed biofilms with significant reductions in the mucosal viability whereas neither CDC587, MN8 (hly+, or MNPE hlaKO, formed biofilms and were less cytotoxic. The addition of exogenous, purified α-toxin to MNPE hlaKO restored the biofilm phenotype. Our studies suggest α-toxin affects S. aureus phenotypic growth on vaginal mucosa, by promoting tissue disruption and biofilm formation; and α–toxin mutants (hly are not benign colonizers, but rather form a different type of infection, which we have termed high density pathogenic

Active immunization with an octa-valent Staphylococcus aureus antigen mixture in models of S. aureus bacteremia and skin infection in mice.

Directory of Open Access Journals (Sweden)

Sanne van den Berg

Full Text Available Proteomic studies with different Staphylococcus aureus isolates have shown that the cell surface-exposed and secreted proteins IsaA, LytM, Nuc, the propeptide of Atl (pro-Atl and four phenol-soluble modulins α (PSMα are invariantly produced by this pathogen. Therefore the present study was aimed at investigating whether these proteins can be used for active immunization against S. aureus infection in mouse models of bacteremia and skin infection. To this end, recombinant His-tagged fusions of IsaA, LytM, Nuc and pro-Atl were isolated from Lactococcus lactis or Escherichia coli, while the PSMα1-4 peptides were chemically synthesized. Importantly, patients colonized by S. aureus showed significant immunoglobulin G (IgG responses against all eight antigens. BALB/cBYJ mice were immunized subcutaneously with a mixture of the antigens at day one (5 μg each, and boosted twice (25 μg of each antigen with 28 days interval. This resulted in high IgG responses against all antigens although the response against pro-Atl was around one log lower compared to the other antigens. Compared to placebo-immunized mice, immunization with the octa-valent antigen mixture did not reduce the S. aureus isolate P load in blood, lungs, spleen, liver, and kidneys in a bacteremia model in which the animals were challenged for 14 days with a primary load of 3 × 10(5 CFU. Discomfort scores and animal survival rates over 14 days did not differ between immunized mice and placebo-immunized mice upon bacteremia with S. aureus USA300 (6 × 10(5 CFU. In addition, this immunization did not reduce the S. aureus isolate P load in mice with skin infection. These results show that the target antigens are immunogenic in both humans and mice, but in the used animal models do not result in protection against S. aureus infection.

Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

Directory of Open Access Journals (Sweden)

Mohammad Mehdi Soltan Dallal

2015-12-01

Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2013. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion methodResults: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

Directory of Open Access Journals (Sweden)

Mohammad Mehdi Soltan Dallal

2016-02-01

Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2014. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion method.Results: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

Structural variations of staphylococcal cassette chromosome mec Type IVa in Staphylococcus aureus clonal complex 8 and unrelated lineages

DEFF Research Database (Denmark)

Damborg, Peter Panduro; Bartels, Mette Damkjær; Boye, Kit

2011-01-01

PCR mapping of staphylococcal cassette chromosome mec type IVa and adjacent mobile elements in 94 methicillin-resistant Staphylococcus aureus (MRSA) strains identified two primary structures (A and B) that could be further classified into two (A1 and A2) and five (B1 to B5) variants, primarily...... based on structural differences in the orfX-J3 region. While spa type t008 (USA300) invariably contained the A variants, other spa types belonging to clonal complex 8 and unrelated lineages generally contained B variants. These findings have important implications for the typing and identification...

Resistência à mupirocina entre isolados de Staphylococcus aureus de profissionais de enfermagem Resistencia al mupirocin en cepas aisladas de Staphylococcus aureus de profesionales de enfermería Mupirocin-resistant Staphylococcus aureus in samples belonging to professional nurses

Directory of Open Access Journals (Sweden)

Josely Pinto de Moura

2010-06-01

Full Text Available OBJETIVOS: Avaliar a colonização por Staphylococcus aureus sensíveis e resistentes à meticilina na saliva de profissionais de enfermagem e o perfil de resistência à mupirocina. MÉTODOS: Foram coletadas três amostras da saliva de 356 (94,2% profissionais participantes da pesquisa, totalizando 1.068 amostras processadas. Todos os aspectos éticos foram contemplados. A análise microbiológica compreendeu a identificação fenotípica, segundo normas do Clinical and Laboratory Standards Institute. RESULTADOS: Foram obtidos 73 indivíduos colonizados por Staphylococcus aureus na primeira coleta, 48 na segunda e 37 na terceira, somando 158 isolados de Staphylococcus aureus. Desses, 24 (15,2% eram resistentes à oxacilina e 30 resistentes à mupirocina (18,9%. A resistência à mupirocina foi observada de forma pronunciada nos Staphylococcus aureus metacilina resistente (MRSA; dos 24 MRSA, 17 (70,8% apresentaram-se resistentes a este antimicrobiano. CONCLUSÃO: Os resultados indicaram que a resistência à mupirocina é um importante problema, pois esse antibiótico é um excelente aliado nas medidas de controle das infecções de serviços de saúde.OBJETIVOS: Evaluar la colonización por Staphylococcus aureus sensibles y resistentes al meticilín en la saliva de profesionales de enfermería y, reconocer el perfil de resistencia a la mupirocina. MÉTODOS: Fueron recolectadas tres muestras de saliva de 356 (94,2% profesionales participantes de la investigación, totalizando 1.068 muestras procesadas. Todos los aspectos éticos fueron contemplados. El análisis microbiológico comprendió la identificación fenotípica, según normas del Clinical and Laboratory Standards Institute. RESULTADOS: Fueron obtenidos 73 individuos colonizados por Staphylococcus aureus en la primera recolección, 48 en la segunda y 37 en la tercera, sumando 158 muestras aisladas de Staphylococcus aureus. De esas, 24 (15,2% eran resistentes a la oxacilina y 30

Staphylococcus aureus Transcriptome Architecture

DEFF Research Database (Denmark)

Mäder, Ulrike; Nicolas, Pierre; Depke, Maren

2016-01-01

Staphylococcus aureus is a major pathogen that colonizes about 20% of the human population. Intriguingly, this Gram-positive bacterium can survive and thrive under a wide range of different conditions, both inside and outside the human body. Here, we investigated the transcriptional adaptation of...

Communications of Staphylococcus aureus and non-aureus Staphylococcus species from bovine intramammary infections and teat apex colonization

DEFF Research Database (Denmark)

Mahmmod, Yasser S.; Klaas, Ilka Christine; Svennesen, Line

2018-01-01

The role of non-aureus staphylococci (NAS) in the risk of acquisition of intramammary infections with Staphylococcus aureus is vague and still under debate. The objectives of this study were to (1) investigate the distribution patterns of NAS species from milk and teat skin in dairy herds with au...

Characterization of methicillin-resistant Staphylococcus aureus Sequence Type 398

DEFF Research Database (Denmark)

Christiansen, Mette Theilgaard

Staphylococcus aureus is an opportunistic pathogen that colonizes the nares and skin surfaces of several animal species, including man. S. aureus can cause a wide variety of infections ranging from superficial soft tissue and skin infections to severe and deadly systemic infections. Traditionally S....... aureus and methicillin-resistant Staphylococcus aureus (MRSA) have been associated with hospitals, but during the past decades MRSA has emerged in the community and now a new branch of MRSA has been found in association with livestock (LA-MRSA). A specific lineage (multilocus sequence type 398 (ST398...

Nasal Staphylococcus aureus and methicillin-resistant Staphylococcus aureus carriage among college student athletes in northern Taiwan

Directory of Open Access Journals (Sweden)

Hong-Kai Wang

2017-08-01

Full Text Available Of 259 college students in northern Taiwan surveyed, nasal carriage rate of Staphylococcus aureus and methicillin-resistant S. aureus (MRSA was 22.4% and 1.54%, respectively and no significant difference was found between athlete students and non-athlete students. Three of four MRSA isolates belonged to sequence type 59, the endemic community clone.

Staphylococcus aureus bacteriuria as a prognosticator for outcome of Staphylococcus aureus bacteremia: a case-control study

Directory of Open Access Journals (Sweden)

Weinstein Robert A

2010-07-01

Full Text Available Abstract Background When Staphylococcus aureus is isolated in urine, it is thought to usually represent hematogenous spread. Because such spread might have special clinical significance, we evaluated predictors and outcomes of S. aureus bacteriuria among patients with S. aureus bacteremia. Methods A case-control study was performed at John H. Stroger Jr. Hospital of Cook County among adult inpatients during January 2002-December 2006. Cases and controls had positive and negative urine cultures, respectively, for S. aureus, within 72 hours of positive blood culture for S. aureus. Controls were sampled randomly in a 1:4 ratio. Univariate and multivariable logistic regression analyses were done. Results Overall, 59% of patients were African-American, 12% died, 56% of infections had community-onset infections, and 58% were infected with methicillin-susceptible S. aureus (MSSA. Among 61 cases and 247 controls, predictors of S. aureus bacteriuria on multivariate analysis were urological surgery (OR = 3.4, p = 0.06 and genitourinary infection (OR = 9.2, p = 0.002. Among patients who died, there were significantly more patients with bacteriuria than among patients who survived (39% vs. 17%; p = 0.002. In multiple Cox regression analysis, death risks in bacteremic patients were bacteriuria (hazard ratio 2.9, CI 1.4-5.9, p = 0.004, bladder catheter use (2.0, 1.0-4.0, p = 0.06, and Charlson score (1.1, 1.1-1.3, p = 0.02. Neither length of stay nor methicillin-resistant Staphylococcus aureus (MRSA infection was a predictor of S. aureus bacteriuria or death. Conclusions Among patients with S. aureus bacteremia, those with S. aureus bacteriuria had 3-fold higher mortality than those without bacteriuria, even after adjustment for comorbidities. Bacteriuria may identify patients with more severe bacteremia, who are at risk of worse outcomes.

Methicillin-Susceptible, Vancomycin-Resistant Staphylococcus aureus, Brazil

OpenAIRE

Panesso , Diana; Planet , Paul J.; Diaz , Lorena; Hugonnet , Jean-Emannuel; Tran , Truc T.; Narechania , Apurva; Munita , José M.; Rincon , Sandra; Carvajal , Lina P.; Reyes , Jinnethe; Londono , Alejandra; Smith , Hannah; Sebra , Robert; Deikus , Gintaras; Weinstock , George M

2015-01-01

International audience; We report characterization of a methicillin-susceptible, vancomycin-resistant bloodstream isolate of Staphylococcus aureus recovered from a patient in Brazil. Emergence of vancomycin resistance in methicillin-susceptible S. aureus would indicate that this resistance trait might be poised to disseminate more rapidly among S. aureus and represents a major public health threat.

Association between phage types and antimicrobial resistance among bovine Staphylococcus aureus from 10 countries

DEFF Research Database (Denmark)

Vintov, J.; Aarestrup, Frank Møller; Zinn, C. E.

2003-01-01

This study was conducted to investigate the diversity of phage types and associations between penicillin resistance and phage types among 815 Staphylococcus aureus isolates from bovine mastitis in nine European countries and USA. All isolates were examined for susceptibility to antimicrobial agents...... associated with penicillin resistance in contrast to phage group I (P = 0.0023) and phage complex-80 (P = 0.0066). This study confirms that a large number of phage types of S. aureus cause bovine mastitis, but that some types predominate. In addition, these findings could indicate that the use of penicillin...... in the bovine environment has selected for specific types of S. aureus in countries with a high frequency of resistance....

Factors determining Staphylococcus aureus susceptibility to photoantimicrobial chemotherapy: RsbU activity, staphyloxanthin level and membrane fluidity.

Directory of Open Access Journals (Sweden)

Monika Kossakowska-Zwierucho

2016-07-01

Full Text Available Photoantimicrobial chemotherapy (PACT constitutes a particular type of stress condition, in which bacterial cells induce a pleiotropic and as yet unexplored effect. In light of this, the key master regulators are of putative significance to the overall phototoxic outcome. In Staphylococcus aureus, the alternative sigma factor σB controls the expression of genes involved in the response to environmental stress. We show that aberration of any sigB operon genes in S. aureus USA300 isogenic mutants causes a pronounced sensitization (>5 log10 reduction in CFU drop to PACT with selected photosensitizers, namely protoporphyrin diarginate, zinc phthalocyanine and rose bengal. This effect is partly due to aberration-coupled staphyloxanthin synthesis inhibition. We identified frequent mutations in RsbU, a σB activator, in PACT-vulnerable clinical isolates of S. aureus, resulting in σB activity impairment. Locations of significant changes in protein structure (IS256 insertion, early STOP codon occurrence, substitutions A230T and A276D were shown in a theoretical model of S. aureus RsbU. As a phenotypic hallmark of PACT-vulnerable S. aureus strains, we observed an increased fluidity of bacterial cell membrane, which is a result of staphyloxanthin content and other yet unidentified factors. Our research indicates σB as a promising target of adjunctive antimicrobial therapy and suggests that enhanced cell membrane fluidity may be an adjuvant strategy in photoantimicrobial chemotherapy.

Prevalence of nasal portal of Staphylococcus aureus in disabled children.

Directory of Open Access Journals (Sweden)

Clotilde Molin

2016-06-01

Full Text Available Introduction: Colonization of the nasal mucosa by Staphylococcus aureus set a carrier state. Which is recognized as a potential source of infection and a high risk factor for subsequent invasive infections. The prevalence of nasal carriage of this germ in disabled children in Paraguay is not known, thus contributing to the knowledge of their frequency and evaluate the profile of sensitivity to common antimicrobials was conducted this study, from May to July 2015.  Objective: to determine the prevalence of Staphylococcus aureus nasal carriage and profile of antimicrobial resistance in disabled children. Materials and Methods: A descriptive cross-sectional study in which 80 nasal swabs of children, who attended the service laboratory of SENADIS (Secretaria Nacional por los Derechos Humanos de las Personas con Discapacidad. The identification and sensitivity of germ was accomplished by conventional testing.  Results: 80 pediatric patients, 46 boys and 34 girls. 18 isolates of Staphylococcus aureus were obtained, corresponding to a prevalence of 22,5%. Susceptibility testing indicated that 14 strains were MSSA (Methicillin – Sensitive Staphylococcus aureus and 4 RMSA ( Methicillin- resistant Staphylococcus aureus. Conclusion: The prevalence of Staphylococcus aureus in a population with its own characteristics provides valuable data for the epidemiology, reflecting the need for continued vigilance and take steps to reduce associated infections. The detection of RMAR evidences their progress; it is important to evaluate the empirical treatment to primary care.

Human factor in Staphylococcus aureus nasal carriage

NARCIS (Netherlands)

J.L. Nouwen (Jan); H.A.M. Boelens (Hélène); A.F. van Belkum (Alex); H.A. Verbrugh (Henri)

2004-01-01

textabstractPersistent nasal carriers and noncarriers of Staphylococcus aureus were inoculated with a mixture of different S. aureus strains. The majority of noncarriers and nearly all persistent carriers returned to their original carrier state after artificial inoculation. Furthermore, the

UJI ZONA HAMBAT EKSTRAK DAUN PUTRI MALU (Mimosa pudica TERHADAP BAKTERI Staphylococcus aureus DAN Methicillin-resistant Staphylococcus aureus (MRSA SECARA IN VITRO

Directory of Open Access Journals (Sweden)

Nyoman Ririn Chandrika Sari

2015-04-01

Full Text Available Resistensi Staphylococcus aureus dan MRSA terhadap antibiotika spektrum luas mendorong berbagai penelitian untuk menemukan senyawa aktif yang sensitif dan efektif dalam menghambat pertumbuhan bakteri.Penelitian ini bertujuan untuk mengetahui efek penghambatan ekstrak daun putri malu (Mimosa pudica terhadap pertumbuhan bakteri Staphylococcus aureus dan MRSA.Penelitian terhadap aktivitas antimikrobial ekstrak daun putri malu dilakukan dengan metode agar difusi cakram dengan menggunakan metode Kirby-Bauer.Suspensi bakteri disesuaikan dengan standar kekeruhan Mc Farland 0.5. Biakan bakteri dalam cawan petri masing-masing diberikan 6 perlakuan, yaitu kontrol positif (amoxicillin atau vancomycin, kontrol negatif (alkohol, serta ekstrak daun putri malu dengan konsentrasi 25 mcg/ml, 50 mcg/ml, 75 mcg/ml dan 100 mcg/ml. Pertumbuhan Staphylococcus aureus dihambat secara signifikan oleh ekstrak daun putri malu, dengan efek inhibisi pada semua konsentrasi secara signifikan lebih baik dibandingkan dengan kontrol positif (p<0.05. Zona inhibisi Staphylococcus aureus pada konsentrasi 25 mcg/ml adalah 28.86 mm dan telah memenuhi kriteria sebagai antimikrobial sensitif berdasarkan Clinical and Laboratory Standard Institute (CLSI. Inhibisi pertumbuhan MRSA secara signifikan terjadi pada semua konsentrasi ekstrak daun putri malu dibandingkan dengan kontrol negatif (p=0.00. Zona inhibisi terbesar ditemukan pada konsentrasi 100 mcg/ml dengan diameter sebesar 14.16 mm dan memiliki efek antimikrobial sebanding dengan vancomycin dalam menghambat pertumbuhan MRSA (p=0.186. Hasil uji agar difusi cakram menunjukkan bahwa senyawa aktif dalam ekstrak daun putri malu memiliki aktivitas antimikrobial yang tinggi terhadap Staphylococcus aureus dan MRSA secara in vitro.

Global analysis of the impact of linezolid onto virulence factor production in S. aureus USA300

NARCIS (Netherlands)

Bonn, Florian; Pane-Farre, Jan; Schlueter, Rabea; Schaffer, Marc; Fuchs, Stephan; Bernhardt, Joerg; Riedel, Katharina; Otto, Andreas; Voelker, Uwe; van Dijl, Jan Maarten; Hecker, Michael; Maeder, Ulrike; Becher, Doerte

The translation inhibitor linezolid is an antibiotic of last resort against Gram-positive pathogens including methicillin resistant strains of the nosocomial pathogen Staphylococcus aureus. Linezolid is reported to inhibit production of extracellular virulence factors, but the molecular cause is

Population structure of Staphylococcus aureus in China

NARCIS (Netherlands)

Yan, Xiaomei

2015-01-01

The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance

Testing the sensitivity of Staphylococcus aureus antibiotics

Directory of Open Access Journals (Sweden)

Marioara Nicoleta FILIMON

2009-11-01

Full Text Available This study has in view to establish and test the sensitivity of Staphylococcus aureus antibiotics. There are different injuries caused by superficial skin infections: from simple pimples to infections that endanger our lives, like an abscess, furuncle septicemia, meningitis, toxic food, urinary tract infection at sexually active young women. Samples have been taken from 30 people with staphylococcus infections. They were nineteen women and eleven men, between the age of 2 and 79. During this study some antibiograms have been made, based on pharyngeal exudates, acne secretion and urine culture. It has been established that the most efficient recommended antibiotics are: oxacilin, erythromycin, rifampicin and ciprofloxacin. The penicillin turned out to be less efficient to remove and destroy the Staphylococcus aureus species.

Infeção por staphylococcus aureus meticilina-resistente da comunidade em Portugal

Directory of Open Access Journals (Sweden)

R. Nazareth

2012-01-01

Full Text Available Resumo: Recentemente assistiu-se à emergência de infeções na comunidade por Staphylococcus aureus meticilina-resistente (MRSA em indivíduos sem fatores de risco. O MRSA associado à comunidade (CA-MRSA parece ser mais virulento, causando desde infeções superficiais da pele e tecidos moles até fasceíte necrosante e, raramente, pneumonia.O CA-MRSA foi inicialmente identificado na Austrália no início da década de 80 e, após cerca de duas décadas, surgiu nos EUA e em vários países da Europa, Ásia e América do Sul. Não existe informação disponível acerca da prevalência em Portugal.Os autores reportam o primeiro caso de infeção por CA-MRSA em Portugal, num adulto jovem com pneumonia necrotizante grave complicada por empiema bilateral e insuficiência respiratória. Abstract: Methicillin-resistant Staphylococcus aureus (MRSA has recently emerged as a cause of community-acquired infections among individuals without risk factors. Community-associated MRSA (CA-MRSA appears to be more virulent, causing superficial mild skin and soft tissue infections to severe necrotizing fasciitis, and in rare cases, pneumonia.Community-associated MRSA was first reported in Australia in the early 80s, after almost two decades in the USA, and then in several countries in Europe, Asia and South America. No data exists in Portugal.We report the first case of CA-MRSA infection in Portugal, in a young adult with severe necrotizing pneumonia, complicated with bilateral empyema and respiratory failure. Palavras-chave: comunidade associada, MRSA, Staphylococcus aureus, pneumonia necrosante, empiema, Keywords: Community-associated, MRSA, Staphylococcus aureus, Necrotizing pneumonia, Empyema

Contribution of Panton-Valentine leukocidin in community-associated methicillin-resistant Staphylococcus aureus pathogenesis.

Directory of Open Access Journals (Sweden)

Binh An Diep

2008-09-01

Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA strains typically carry genes encoding Panton-Valentine leukocidin (PVL. We used wild-type parental and isogenic PVL-deletion (Delta pvl strains of USA300 (LAC and SF8300 and USA400 (MW2 to test whether PVL alters global gene regulatory networks and contributes to pathogenesis of bacteremia, a hallmark feature of invasive staphylococcal disease. Microarray and proteomic analyses revealed that PVL does not alter gene or protein expression, thereby demonstrating that any contribution of PVL to CA-MRSA pathogenesis is not mediated through interference of global gene regulatory networks. Inasmuch as a direct role for PVL in CA-MRSA pathogenesis remains to be determined, we developed a rabbit bacteremia model of CA-MRSA infection to evaluate the effects of PVL. Following experimental infection of rabbits, an animal species whose granulocytes are more sensitive to the effects of PVL compared with the mouse, we found a contribution of PVL to pathogenesis over the time course of bacteremia. At 24 and 48 hours post infection, PVL appears to play a modest, but measurable role in pathogenesis during the early stages of bacteremic seeding of the kidney, the target organ from which bacteria were not cleared. However, the early survival advantage of this USA300 strain conferred by PVL was lost by 72 hours post infection. These data are consistent with the clinical presentation of rapid-onset, fulminant infection that has been associated with PVL-positive CA-MRSA strains. Taken together, our data indicate a modest and transient positive effect of PVL in the acute phase of bacteremia, thereby providing evidence that PVL contributes to CA-MRSA pathogenesis.

Cemaran Staphylococcus aureus dan Pseudomonas aerogenosa Pada Stetoskop dirumah Sakit

Directory of Open Access Journals (Sweden)

leka lutpiatina

2017-10-01

The result of the research was found contamination of Staphylococcus aureus and Pseudomonas aerogenosa on steteskop. The site home condition of the research data was 66.7% cleaned daily, the storage method was placed on the table 70% and the duration of using the set home more than 1 year as much as 70%. The conclusion of stethoscope at Banjarbaru Hospital was contaminated with Staphylococcus aureus by 70% and Pseudomonas aerogenosa by 17%. The suggestion of research can be continued by knowing the existence of Staphylococcus aureus resistant antibiotic and Pseudomonas aerogenous antibiotic resistant at steteskop at Hospital.

The human nasal microbiota and Staphylococcus aureus carriage.

Directory of Open Access Journals (Sweden)

Daniel N Frank

Full Text Available BACKGROUND: Colonization of humans with Staphylococcus aureus is a critical prerequisite of subsequent clinical infection of the skin, blood, lung, heart and other deep tissues. S. aureus persistently or intermittently colonizes the nares of approximately 50% of healthy adults, whereas approximately 50% of the general population is rarely or never colonized by this pathogen. Because microbial consortia within the nasal cavity may be an important determinant of S. aureus colonization we determined the composition and dynamics of the nasal microbiota and correlated specific microorganisms with S. aureus colonization. METHODOLOGY/PRINCIPAL FINDINGS: Nasal specimens were collected longitudinally from five healthy adults and a cross-section of hospitalized patients (26 S. aureus carriers and 16 non-carriers. Culture-independent analysis of 16S rRNA sequences revealed that the nasal microbiota of healthy subjects consists primarily of members of the phylum Actinobacteria (e.g., Propionibacterium spp. and Corynebacterium spp., with proportionally less representation of other phyla, including Firmicutes (e.g., Staphylococcus spp. and Proteobacteria (e.g. Enterobacter spp. In contrast, inpatient nasal microbiotas were enriched in S. aureus or Staphylococcus epidermidis and diminished in several actinobacterial groups, most notably Propionibacterium acnes. Moreover, within the inpatient population S. aureus colonization was negatively correlated with the abundances of several microbial groups, including S. epidermidis (p = 0.004. CONCLUSIONS/SIGNIFICANCE: The nares environment is colonized by a temporally stable microbiota that is distinct from other regions of the integument. Negative association between S. aureus, S. epidermidis, and other groups suggests microbial competition during colonization of the nares, a finding that could be exploited to limit S. aureus colonization.

Front-Loaded Linezolid Regimens Result in Increased Killing and Suppression of the Accessory Gene Regulator System of Staphylococcus aureus

Science.gov (United States)

Brown, Tanya; Parasrampuria, Ridhi; Brazeau, Daniel A.; Forrest, Alan; Kelchlin, Pamela A.; Holden, Patricia N.; Peloquin, Charles A.; Hanna, Debra; Bulitta, Jurgen B.

2012-01-01

Front loading is a strategy used to optimize the pharmacodynamic profile of an antibiotic through the administration of high doses early in therapy for a short duration. Our aims were to evaluate the impact of front loading of linezolid regimens on bacterial killing and suppression of resistance and on RNAIII, the effector molecule of the accessory gene regulator system (encoded by agr) in methicillin-resistant Staphylococcus aureus (MRSA). Time-killing experiments over 48 h were utilized for linezolid against four strains of MRSA: USA100, USA300, USA400, and ATCC 29213. A hollow-fiber infection model simulated traditional and front-loaded human therapeutic regimens of linezolid versus USA300 at 106 CFU/ml over 240 h. Over 48 h in time-kill experiments, linezolid displayed bacteriostatic activity, with reductions of >1 log10 CFU/ml for all strains. Front-loaded regimens that were administered over 5 days, 1,200 mg every 12 h (q12h) (total, 10 doses) and 2,400 mg q12h (total, 10 doses) followed by 300 mg q12h thereafter, resulted in sustained bactericidal activity, with reductions of the area under the CFU curve of −6.15 and −6.03, respectively, reaching undetectable limits at the 10-day study endpoint. All regimens displayed a reduction in RNAIII relative expression at 24 h and 240 h compared with that of the growth control. Monte Carlo simulations predicted a linezolid are promising and may be of utility in severe MRSA infections, where early aggressive therapy is necessary. PMID:22526313

Quality control of direct molecular diagnostics for methicillin-resistant Staphylococcus aureus

NARCIS (Netherlands)

van Belkum, Alex; Niesters, Hubert G M; MacKay, William G; van Leeuwen, Willem B

Ten samples containing various amounts of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus, methicillin-resistant Staphylococcus epidermidis (MRSE), and combinations thereof were distributed to 51 laboratories for molecular diagnostics testing. Samples containing

Long-term mortality after Staphylococcus aureus spondylodiscitis

DEFF Research Database (Denmark)

Aagaard, Theis; Roed, Casper; Larsen, Anders R

2014-01-01

Patients diagnosed with Staphylococcus aureus spondylodiscitis have increased long-term mortality compared with the background population mainly due to infectious, endocrine, cardiovascular, gastrointestinal and alcohol and drug abuse-related diseases.......Patients diagnosed with Staphylococcus aureus spondylodiscitis have increased long-term mortality compared with the background population mainly due to infectious, endocrine, cardiovascular, gastrointestinal and alcohol and drug abuse-related diseases....

Molecular Characterization of Endocarditis-Associated Staphylococcus aureus

OpenAIRE

Nethercott, Cara; Mabbett, Amanda N.; Totsika, Makrina; Peters, Paul; Ortiz, Juan C.; Nimmo, Graeme R.; Coombs, Geoffrey W.; Walker, Mark J.; Schembri, Mark A.

2013-01-01

Infective endocarditis (IE) is a life-threatening infection of the heart endothelium and valves. Staphylococcus aureus is a predominant cause of severe IE and is frequently associated with infections in health care settings and device-related infections. Multilocus sequence typing (MLST), spa typing, and virulence gene microarrays are frequently used to classify S. aureus clinical isolates. This study examined the utility of these typing tools to investigate S. aureus epidemiology associated ...

Identifying conditions for elimination and epidemic potential of methicillin-resistant Staphylococcus aureus in nursing homes

Directory of Open Access Journals (Sweden)

Nataliya G. Batina

2016-09-01

Full Text Available Abstract Background Residents of nursing homes are commonly colonized with methicillin-resistant Staphylococcus aureus (MRSA but there is a limited understanding of the dynamics and determinants of spread in this setting. To address this gap, we sought to use mathematical modeling to assess the epidemic potential of MRSA in nursing homes and to determine conditions under which non-USA300 and USA300 MRSA could be eliminated or reduced in the facilities. Methods Model parameters were estimated from data generated during a longitudinal study of MRSA in 6 Wisconsin nursing homes. The data included subject colonization status with strain-specific MRSA collected every 3 months for up to 1 year. Deterministic and stochastic co-colonization and single-strain models were developed to describe strain-specific dynamics of MRSA in these facilities. Basic reproduction numbers of strain-independent MRSA, non-USA300 and USA300 MRSA were estimated numerically. The impact of antibiotic use in the past 3 months on the prevalence of strain-specific MRSA and associated basic reproduction numbers were evaluated. Results Our models predicted that MRSA would persist in Wisconsin nursing homes, and non-USA300 would remain the dominant circulating strain. MRSA eradication was theoretically achievable by elimination of MRSA-positive admissions over the course of years. Substantial reductions in MRSA prevalence could be attained through marked increase in clearance rates or reduction in MRSA-positive admissions sustained over years. The basic reproduction number of strain-independent MRSA was 0.18 (95 % CI = 0.13–0.23. Recent antibiotic use increased the prevalence of strain-specific MRSA and associated basic reproduction numbers, but was unlikely to lead to an outbreak. Conclusions Based on our model, MRSA elimination from nursing homes, while theoretically possible, was unlikely to be achieved in practice. Decolonization therapy that can sustain higher

Relationship and susceptibility profile of Staphylococcus aureus infection diabetic foot ulcers with Staphylococcus aureus nasal carriage.

Science.gov (United States)

Taha, Aza Bahadeen

2013-03-01

Staphylococcus aureus is the main cause of diabetic foot infection with the patient's endogenous flora as the principal source. Nasal carriage of S. aureus has been identified as an important risk factor for the acquisition of diabetic foot infections. The study assessment the associations of S. aureus with methicillin resistant S. aureus were isolation from diabetic foot infection and nasal carriage of the same patients and their antibiotic susceptibility profile. Diagnosis of S. aureus and methicillin resistant S. aureus were carried out by using standard procedures. Antibiotic sensitivity profiles were determent by breakpoint dilution method. Out of 222 S. aureus isolation, 139 (62.61%) were isolated from the diabetic foot and 83 (37.39%) from the nasal carriage. Seventy one (30.87%) of the patients were S. aureus infection diabetic foot with nasal carriage. Among diabetic foot infection and nasal carriage patients, 40.85% of S. aureus were considered as methicillin resistant S. aureus. Rifampicin (96.40%) and Levofloxacin (91.44%) were active against S. aureus. Patients at strong risk for methicillin resistant S. aureus nasal carriage and subsequent diabetic foot infection with high resistance to antibiotics. Copyright © 2012 Elsevier Ltd. All rights reserved.

Selective biosensing of Staphylococcus aureus using chitosan quantum dots

Science.gov (United States)

Abdelhamid, Hani Nasser; Wu, Hui-Fen

2018-01-01

Selective biosensing of Staphylococcus aureus (S. aureus) using chitosan modified quantum dots (CTS@CdS QDs) in the presence of hydrogen peroxide is reported. The method is based on the intrinsic positive catalase activity of S. aureus. CTS@CdS quantum dots provide high dispersion in aqueous media with high fluorescence emission. Staphylococcus aureus causes a selective quenching of the fluorescence emission of CTS@CdS QDs in the presence of H2O2 compared to other pathogens such as Escherichia coli and Pseudomonas aeruginosa. The intrinsic enzymatic character of S. aureus (catalase positive) offers selective and fast biosensing. The present method is highly selective for positive catalase species and requires no expensive reagents such as antibodies, aptamers or microbeads. It could be extended for other species that are positive catalase.

Photoreactivation of ultraviolet-irradiation damage in Staphylococcus aureus

International Nuclear Information System (INIS)

Adkins, B. Jr.; Allen, W.E.

1982-01-01

This study reports the capacity of Staphylococcus aureus strain 7 - 8 to undergo photoenzymatic repair of UV-irradiation induced damage and compares it to the photoreactivation (PR) response of Escherichia coli strain B. Staphylococcus aureaus showed greater inhibition by UV irradiation than E. coli, consistent with its higher adenine and thymine content of DNA. Staphylococcus aureus showed an enhanced rate of photoreactivation with no lag in initiation of the PR response at low PR doses compared to E. coli. Maximum PR capacity of both cultures was about equal and occurred in cultures incubated at 23 - 25 0 . The PR responses at 11 - 12 and 35 - 37 0 for S. aureus and E. coli differed although both were capable of PR at each of these temperatures. The PR response of E. coli was directly related to the dosage of PR light (J/m 2 ); however, the photoenzymatic capacity of S. aureus was not directly responsive to continued decrease in light intensity. The capacity of S. aureus to undergo liquid holding recovery (LHR) occurred at 23 - 25 0 (not at 11 - 12 0 or 35 - 37 0 ), whereas E. coli underwent LHR at 11 - 12 0 and 23 - 25 0 but not at 35 - 37 0 . The LHR response of S. aureus was somewhat more effective than E. coli and did not show the direct response to increased liquid-holding period as did E. coli. (author)

Antibiotic resistance of Staphylococcus aureus isolated from fresh ...

African Journals Online (AJOL)

Antibiotic resistance of Staphylococcus aureus isolated from fresh cow milk in settled ... produced alpha haemolysin, 45.5% (n=25) produced beta haemolysin and ... resistant strains of S. aureus of animal and human biotypes and can serve as ...

Population structure of Staphylococcus aureus in China

OpenAIRE

Yan, Xiaomei

2015-01-01

The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance against rifampicin doubled to 68%. Staphylococcal food poisoning (SFP) is frequent in China. Two predominant S. aureus lineages, ST6 and ST943, were identified causing outbreaks of SFP in Southern China...

[Change in drug resistance of Staphylococcus aureus].

Science.gov (United States)

Lin, Yan; Liu, Yan; Luo, Yan-Ping; Liu, Chang-Ting

2013-11-01

To analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications. The SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines. SAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years. Drug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

Concurrent infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus bacteremia.

Science.gov (United States)

Wang, Li Jun; Du, Xiao Qin; Nyirimigabo, Eric; Shou, Song Tao

2014-04-01

It is rare to see a concurrent infection with infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus in Tianjin, China. Until now, there is still no any single recorded case of concurrent infectious mononucleosis and community-associated methicillin-resistant Staphylococcus aureus bacteremia.

Healing Potentials of Oral Moringa Oleifera Leaves Extract and Tetracycline on Methicillin Resistant Staphylococcus Aureus Infected Wounds of Wistar rats.

Science.gov (United States)

Eyarefe, Oghenemega D; Idowu, Aderayo; Afolabi, Jeremiah M

2015-12-20

The effects of oral dose of aqueous extract of Moringa oleifera and tetracycline antibiotics on cutaneous wounds infected with Staphylococcus aureus were studied in eighteen adult wistar rats (159±31.5g) randomized into three groups: Group A, n = 6, Moringa oleifera-(300 mg/kg). Group B, n = 6, tetracycline (9.4 mg/kg) and Group C, n = 6, Sterile water (control). Six millimetres diameter nape wound, created on each rat under 2% xylazine (5 mg/kg) and 5% ketamine (35 mg/kg), was contaminated with Staphylococcus aureus (108 Colony Forming Unit (CFU). Following infection, treatment was commenced with daily oral dose of test preparations and the wounds were evaluated every other day i.e., day 3, 5, 7, 9, 11, 13 and 15 for wetness (wound exudation), wound edge oedema, hyperaemia, granulation tissues and contraction (diameter). Severe wound exudation existed in all the groups between days 0-3 (p = 1.00). A significantly less wound exudation was observed at days 3-5 (p = 0.000) and 5-9 (p = 0.003) (ControlMoringa). Wound edge oedema was significantly less on days 5-9 (p = 0.000) and 9-15 (p = 0.001) (ControlMoringaMoringa Moringa> Tetracycline). Differences in wound diameter was not significant except at days 5-9 (p = 0.013) (Control> Moringa >Tetracycline). Oral doses of Moringa oleifera extract (300mg/kg) and tetracycline (9.4mg/kg) are not effective as antimicrobial or immune-boosting agents to enhance healing of wounds infected with Staphylococcus aureus and hence not recommended for rapid clearance of Staphylococcus aureus infected wounds.

Intercenter reproducibility of binary typing for Staphylococcus aureus

NARCIS (Netherlands)

van Leeuwen, Willem B.; Snoeijers, Sandor; van der Werken-Libregts, Christel; Tuip, Anita; van der Zee, Anneke; Egberink, Diane; de Proost, Monique; Bik, Elisabeth; Lunter, Bjorn; Kluytmans, Jan; Gits, Etty; van Duyn, Inge; Heck, Max; van der Zwaluw, Kim; Wannet, Wim; Noordhoek, Gerda T.; Mulder, Sije; Renders, Nicole; Boers, Miranda; Zaat, Sebastiaan; van der Riet, Daniëlle; Kooistra, Mirjam; Talens, Adriaan; Dijkshoorn, Lenie; van der Reyden, Tanny; Veenendaal, Dick; Bakker, Nancy; Cookson, Barry; Lynch, Alisson; Witte, Wolfgang; Cuny, Christa; Blanc, Dominique; Vernez, Isabelle; Hryniewicz, Waleria; Fiett, Janusz; Struelens, Marc; Deplano, Ariane; Landegent, Jim; Verbrugh, Henri A.; van Belkum, Alex

2002-01-01

The reproducibility of the binary typing (BT) protocol developed for epidemiological typing of Staphylococcus aureus was analyzed in a biphasic multicenter study. In a Dutch multicenter pilot study, 10 genetically unique isolates of methicillin-resistant S. aureus (MRSA) were characterized by the BT

The changing epidemiology of Staphylococcus aureus bloodstream infection

DEFF Research Database (Denmark)

Laupland, K.B.; Lyytikäinen, O.; Søgaard, Mette

2013-01-01

Clin Microbiol Infect ABSTRACT: Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance w...

Preliminary study of community-acquired Staphylococcus aureus infection in Manaus Hospital, Amazonia Region, Brazil Estudo preliminar das infeccões por Staphylococcus aureus na comunidade de um Hospital em Manaus, Região do Amazonas, Brasil

Directory of Open Access Journals (Sweden)

Jesus M. Egido

2003-12-01

Full Text Available Methicillin resistant Staphylococcus aureus is considered a public health problem with a strong potential for dissemination and high rates of morbidity and mortality. In this study we describe bacteriological and epidemiological characteristics of Staphylococcus aureus in Manaus (Amazon region. During the one-year study period (2000-2001, sixteen cases of acute pyogenic multiple abscess were evaluated. Community-acquired S. aureus was identified as causative agent in 10 (62.5% patients. The strains tested with antimicrobials by discs diffusion method, exhibited a high rate of sensitivity to cephalexin (100%, erythromycin (90%. Oxacillin-susceptible Staphylococcus aureus was 90%. No isolate was resistant to Vancomycin. To our knowledge, no series of community-acquired Staphylococcus aureus in Manaus hospital has been published. Our partial results showed a high rate of antimicrobial sensitivity among community-acquired Staphylococcus aureus in the hospital of Tropical Medicine Institute of Manaus, Amazon Region.O Staphylococcus aureus resistente a meticilina é considerado como um problema na saúde publica por seu grande potencial de disseminação e altas porcentagens de morbidade e mortalidade. No estudo descrevemos as características bacteriológicas e epidemiológicas do Staphylococcus aureus na cidade de Manaus. No período de um ano (2000-2001 avaliou-se dezesseis casos de abscessos piogênicos múltiplos. Em 10 (62,5% doentes o agente causal foi identificado como Staphylococcus aureus adquirido na comunidade O estudo das bacterias isoladas frente aos diferentes antimicrobianos, seguindo o método de difusão em disco, mostrou boa sensibilidade a cefalexina (100% e eritromicina (90%. Noventa porcento dos Staphylococcus aureus isolados foram sensíveis ao oxacilina. Nenhum dos isolados mostrou ser resistente a Vancomicina. Não temos informações sobre publicações dos Staphylococcus aureus adquiridos na comunidade em hospitais de Manaus

Detecting Staphylococcus aureus in milk from dairy cows using sniffer dogs.

Science.gov (United States)

Fischer-Tenhagen, C; Theby, V; Krömker, V; Heuwieser, W

2018-05-01

Fast and accurate identification of disease-causing pathogens is essential for specific antimicrobial therapy in human and veterinary medicine. In these experiments, dogs were trained to identify Staphylococcus aureus and differentiate it from other common mastitis-causing pathogens by smell. Headspaces from agar plates, inoculated raw milk samples, or field samples collected from cows with Staphylococcus aureus and other mastitis-causing pathogens were used for training and testing. The ability to learn the specific odor of Staphylococcus aureus in milk depended on the concentration of the pathogens in the training samples. Sensitivity and specificity for identifying Staphylococcus aureus were 91.3 and 97.9%, respectively, for pathogens grown on agar plates; 83.8 and 98.0% for pathogens inoculated in raw milk; and 59.0 and 93.2% for milk samples from mastitic cows. The results of these experiments underline the potential of odor detection as a diagnostic tool for pathogen diagnosis. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Nasal carriage of methicilli-resistant staphylococcus aureus with ...

African Journals Online (AJOL)

Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. Seventy-two percent (72%) of the isolates were methicillin-resistant S. aureus, while 20% were methicillin-susceptible. The isolates were generally resistant to multiple ...

Antimicrobial resistant coagulase positive Staphylococcus aureus ...

African Journals Online (AJOL)

ADEYEYE

Staphylococcus aureus is an Important agent of food poisoning. In many countries, it ... humans and animals (Casey et al., 2007). ... of widespread use of antibiotics in animals for ... Laboratory Standards Institute methods (CLSI, 2010). Briefly ...

Phenotypic occurrence of methicillin-resistant Staphylococcus ...

African Journals Online (AJOL)

To assess the occurrence of MRSA among camels in Kano abattoir, a total of 300 nasal swabs were collected from camels at the lairage in Kano abattoir, Kano state, Nigeria to isolate and biochemically characterize Staphylococcus aureus and confirm methicillin-resistant Staphylococcus aureus among isolates using ...

Determinants of carriage of resistant Staphylococcus aureus among S. aureus carriers in the Indonesian population inside and outside hospitals

NARCIS (Netherlands)

E.S. Lestari (Endang Sri); D.O. Duerink (Offra); U. Hadi (Usman); J.A. Severin (Juliëtte); N.J.D. Nagelkerke (Nico); K. Kuntaman (Kuntaman); H. Wahjono (Hendro); W. Gardjito (Widjoseno); A. Soejoenoes (Ariawan); P. van den Broek (Peterhans); M. Keuter (Monique); I.C. Gyssens (Inge); H.A. Verbrugh (Henri)

2010-01-01

textabstractOBJECTIVES: To identify determinants of carriage of resistant Staphylococcus aureus in both hospitalized patients and individuals from the community in two urban centres in Indonesia. METHODS: Staphylococcus aureus cultures and data on recent antibiotic use, demographic, socioeconomic,

Detection of some virulence factors in Staphylococcus aureus ...

African Journals Online (AJOL)

USER

2010-06-21

Jun 21, 2010 ... Mastitis is one of the common diseases of dairy cattle and an inflammatory ... Key words: Bovine mastitis, Staphylococcus aureus, virulence factors, ... frequent cause of subclinical intramammary infections in ... genotypes has not been investigated. ... genes in S. aureus, we were particularly interested in the.

Fermentation of Propionibacterium acnes, a commensal bacterium in the human skin microbiome, as skin probiotics against methicillin-resistant Staphylococcus aureus.

Directory of Open Access Journals (Sweden)

Muya Shu

Full Text Available Bacterial interference creates an ecological competition between commensal and pathogenic bacteria. Through fermentation of milk with gut-friendly bacteria, yogurt is an excellent aid to balance the bacteriological ecosystem in the human intestine. Here, we demonstrate that fermentation of glycerol with Propionibacterium acnes (P. acnes, a skin commensal bacterium, can function as a skin probiotic for in vitro and in vivo growth suppression of USA300, the most prevalent community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA. We also promote the notion that inappropriate use of antibiotics may eliminate the skin commensals, making it more difficult to fight pathogen infection. This study warrants further investigation to better understand the role of fermentation of skin commensals in infectious disease and the importance of the human skin microbiome in skin health.

Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk)

OpenAIRE

Pellegrino, MS; Frola, ID; Odierno, LM; Bogni, CI

2011-01-01

ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

Invasive Staphylococcus aureus infection in an African adolescent ...

African Journals Online (AJOL)

Staphylococcus aureus remains an important cause of mortality, in the community and health care set-ups. S. aureus strains with genes encoding lethal toxins and culture negative sepsis augment the diagnostic challenge in resource limited settings. With a growing rate of resistance to the causative bacteria and atypical ...

Association between phage types and antimicrobial resistance among bovine isolates of Staphylococcus aureus in 10 countries

DEFF Research Database (Denmark)

Vintov, J.; Aarestrup, Frank Møller; Zinn, C. E.

2003-01-01

This study was conducted to investigate the diversity of phage types and associations between penicillin resistance and phage types among 815 Staphylococcus aureus isolates from bovine mastitis in nine European countries and USA. All isolates were examined for susceptibility to antimicrobial agents...... associated with penicillin resistance in contrast to phage group I (P = 0.0023) and phage complex-80 (P = 0.0066). This study confirms that a large number of phage types of S. aureus cause bovine mastitis, but that some types predominate. In addition, these findings could indicate that the use of penicillin...... in the bovine environment has selected for specific types of S. aureus in countries with a high frequency of resistance. (C) 2003 Elsevier B.V. All rights reserved....

Prevalence of Methicillin and Vancomycin resistant Staphylococcus aureus colonization in nasopharynx; Amir-Alam hospital, 2005

Directory of Open Access Journals (Sweden)

Hasibi M

2007-07-01

Full Text Available Background: Staphylococcus aureus is one of the most common causes of nosocomial infections with high morbidity and mortality rate. Traditionally, methicillin resistant staphylococcus aureus has been considered a major nosocomial pathogen in healthcare facilities, but in the past decade, it has been observed emerging in the community as well. Informations regarding hospital microbial colonization could be an important step for prevention of nosocomial infections. Our objective was clarifying the prevalence of methicillin resistant and vancomycin resistant staphylococcus aureus colonization in nasopharynx. Methods: A descriptive cross sectional study was carried on 106 patients and nursing staff of surgery and hemodialysis wards in Amir-Alam hospital from April 2005 to July 2005. The samples were collected from nasal region of cases using cotton swab by two experienced technician and were sent to laboratory for culture and antibiogram. Results: Twenty six (29.5% out of 106 cases were nasopharyngeal carriers of staphylococcus aureus. Eight cases (7.5% had methicillin resistant staphylococcus aureus. The most frequent colonization rate was seen in hemodialysis nursing staff and in all of them methicillin resistant staphylococcus aureus was reported. Carrier rates in hemodialysis patients were twice compared to surgery ward patients. The interesting point was that no sample of vancomycin resistant staphylococcus aureus was isolated. Conclusion: Prevalence of methicillin resistant staphylococcus aureus colonization seems to be increased; therefore proper management for controlling this problem is mandatory. The results of the present study suggest that the prevalence of methicillin resistant staphylococcus aureus infections is higher than was expected in Iran and vigorous preventive strategies should therefore be taken to stop the growth of this major health problem.

Staphylococcus aureus: methicillin-susceptible S. aureus to methicillin-resistant S. aureus and vancomycin-resistant S. aureus.

Science.gov (United States)

Rehm, Susan J; Tice, Alan

2010-09-15

The evolution of methicillin-resistant and vancomycin-resistant Staphylococcus aureus has demanded serious review of antimicrobial use and development of new agents and revised approaches to prevent and overcome drug resistance. Depending on local conditions and patient risk factors, empirical therapy of suspected S. aureus infection may require coverage of drug-resistant organisms with newer agents and novel antibiotic combinations. The question of treatment with inappropriate antibiotics raises grave concerns with regard to methicillin-resistant S. aureus selection, overgrowth, and increased virulence. Several strategies to reduce the nosocomial burden of resistance are suggested, including shortened hospital stays and outpatient parenteral antimicrobial therapy of the most serious infections.

Molecular characterization of antimicrobial resistance genes against Staphylococcus aureus isolates from Trinidad and Tobago.

Science.gov (United States)

Akpaka, Patrick E; Roberts, Rashida; Monecke, Stefan

Staphylococcus aureus continues to pose major public health challenges in many areas because of antibiotic resistance problems. In the Caribbean, especially Trinidad and Tobago, the challenge is not different. This study was performed to evaluate the antimicrobial resistance gene prevalence among S. aureus isolates in Trinidad and Tobago. Standard and molecular microbiological methods, including the Microscan automated system, DNA microarray and multi locus sequence typing (MLST) analysis, were performed on 309 clinical S. aureus isolates recovered from patients who were treated at three of the country's main health institutions. S. aureus exhibited susceptibilities ≥80% to eleven of the 19 antimicrobials tested against it, and these belong to the most commonly used and available antibiotics in the country. While the antibiotic to which it was most susceptible of the commonly used antibiotics was trimethoprim/sulfamethoxazole, the antibiotics to which it was least susceptible or most resistant to were ampicillin and penicillin. S. aureus isolates from the pediatric ward produced the greatest rate of susceptibility among the isolates recovered from patients admitted into hospitals, while isolates from Accident and Emergency rooms displayed the greatest susceptibilities among patients from the community. S. aureus isolates from the country did not harbor acquired resistant genes targeting clindamycin/macrolides (ermB), linezolid (cfr) or vancomycin (vanA). The blaZ gene, which is the most common beta lactam (Penicillinase) resistance mechanism for S. aureus, was observed in 88.7% of the methicillin susceptible S. aureus, while methicillin resistance mediated by the mec gene was present in 13.6%. Most of the resistance markers found in MRSA isolates were significantly associated with the ST239-MRSA-III strain in this study, and all isolates that belonged to the USA300 strain, which additionally encoded both the PVL gene and ACME cluster, belonged to CC8. Several

Prevalence of Staphylococcus aureus colonization in renal transplant patients

Directory of Open Access Journals (Sweden)

Luiz Carlos Ribeiro Lamblet

2014-10-01

Full Text Available Objective to evaluate the prevalence of Staphylococcus aureus nasal colonization in renal transplant patients and to identify the related risk factors. Method Swabs were used to collect nasal samples from 160 patients who had undergone a transplant within the previous year at the Kidney and Hypertension Hospital. The ‘National Committee for Clinical Laboratory Standards’ norms were followed for the collection, isolation, identification and sensitivity measurements. Results There was a 9.4% (15 prevalence of Staphylococcus aureus nasal colonization, of which one (6.7% was resistant to oxacillin. It was possible to identify as an associated risk factor a wait of more than one year for accessing dialysis prior to the transplant (p=0.029. Conclusion Given the high morbidity and mortality rates that this microorganism causes in the target population, other studies should be carried out, and pre- and post-transplant screening should occur in order to develop strategies that improve the prevention and control of the spread of Staphylococcus aureus.

Characterization of Staphylococcus aureus Strains Associated with Food Poisoning in Shenzhen, China

NARCIS (Netherlands)

Yan, Xiaomei; Wang, Bing; Tao, Xiaoxia; Hu, Qinghua; Cui, Zhigang; Zhang, Jianzhong; Lin, Yiman; You, Yuanhai; Shi, Xiaolu; Grundmann, Hajo

To characterize isolates of Staphylococcus aureus that were associated with staphylococcal food poisoning between 2006 and 2009 in Shenzhen, Southern China, a total of 52 Staphylococcus aureus isolates from 11 outbreaks were analyzed by using multilocus sequence typing (MLST), spa typing, and

Beta-lactamase detection in Staphylococcus aureus and coagulase-negative Staphylococcus isolated from bovine mastitis

Directory of Open Access Journals (Sweden)

Bruno F. Robles

2014-04-01

Full Text Available The objectives of the study were to evaluate the presence/production of beta-lactamases by both phenotypic and genotypic methods, verify whether results are dependent of bacteria type (Staphylococcus aureus versus coagulase-negative Staphylococcus - CNS and verify the agreement between tests. A total of 200 bacteria samples from 21 different herds were enrolled, being 100 CNS and 100 S. aureus. Beta-lactamase presence/detection was performed by different tests (PCR, clover leaf test - CLT, Nitrocefin disk, and in vitro resistance to penicillin. Results of all tests were not dependent of bacteria type (CNS or S. aureus. Several S. aureus beta-lactamase producing isolates were from the same herd. Phenotypic tests excluding in vitro resistance to penicillin showed a strong association measured by the kappa coefficient for both bacteria species. Nitrocefin and CLT are more reliable tests for detecting beta-lactamase production in staphylococci.

A porcine model of haematogenous brain infectionwith staphylococcus aureus

DEFF Research Database (Denmark)

Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg

2012-01-01

A PORCINE MODEL OF HAEMATOGENOUS BRAIN INFECTION WITH STAPHYLOCOCCUS AUREUS Astrup Lærke1, Agerholm Jørgen1, Nielsen Ole1, Jensen Henrik1, Leifsson Páll1, Iburg Tine2. 1: Faculty of Health and Medical Sciences, University of Copenhagen, Denmark boye@life.ku.dk 2: National Veterinary Institute......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...... thromboemboli (two pigs). The venous catheter was used for blood sampling before, during and after inoculation. The pigs were euthanized either 24 or 48 hours after inoculation. The brains were collected and examined histologically. Results We describe unifocal suppurative encephalitis 48 hours after...

Occurrence and antimicrobial resistance of Staphylococcus aureus in bulk tank milk and milk filters

Directory of Open Access Journals (Sweden)

Kateřina Bogdanovičová

2014-02-01

Full Text Available This work is focused on the monitoring of Staphylococcus aureus prevalence in raw milk and milk filters, its antibiotic resistance and detection of methicillin resistant Staphylococcus aureus (MRSA. Samples of raw cow´s milk and milk filters were collected in the period from 2012 till 2014, from 50 dairy farms in the Czech Republic. The total of 261 samples (164 samples of raw milk and 97 milk filters were cultivated on Baird-Parker agar. Both the typical and atypical colonies were examined by plasmacoagulase test and PCR method was used for detection of species specific fragment SA442 and mecA gene. Standard disk diffusion method was used to determinate resistance to antimicrobial agents. The bacterium Staphylococcus aureus was detected on 25 farms (50%. The antimicrobial resistance showed differences between the farms. Total of 58 samples were positive for Staphylococcus aureus, of which were 37 (14.2% isolated from raw milk samples and 21 (8.1% from milk filters. From these samples we isolated 62 Staphylococcus aureus strains, 41 isolates bacteria S. aureus from raw milk (66.1% and 21 isolates S. aureus from milk filters (33.9%. The presence of antibiotic resistance in Staphylococcus aureus isolates was low, most of them were resistant to amoxicilin. According to the results obtained by the PCR method for the methicillin - resistant S. aureus (MRSA, the mecA gene was present in 6 strains (9.7%, 4 isolates obtained from milk samples (6.5% and 2 isolates from milk filters (3.2%.  These isolates can be considered as a possible source of resistance genes, which can be spread through the food chain. Nowadays, a globally unfavourable increasing trend of prevalence of methicillin resistant staphylococci strains especially Staphylococcus aureus is being observed worldwide. The improper hygiene and poor farm management practices contributed to the presence of S. aureus in the milk. This may have contributed to the high level of S. aureus isolated

Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant Staphylococcus aureus: a European cross-sectional study.

NARCIS (Netherlands)

Heijer, C.D.J. den; Bijnen, E.M.E. van; Paget, W.J.; Pringle, M.; Goossen, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

2014-01-01

Background: Information on the prevalence of Staphylococcus aureus resistance has mainly been obtained from invasive strains, although the commensal flora is considered an important reservoir of resistance. Within ‘The Appropriateness of prescribing antibiotics in primary health care in Europe with

Methicillin-resistant Staphylococcus aureus in pigs and farm workers on conventional and antibiotic-free swine farms in the USA.

Directory of Open Access Journals (Sweden)

Tara C Smith

Full Text Available Much uncertainty remains about the origin and public health implications of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA. This study aimed to investigate the occurrence and prevalence of MRSA in general and LA-MRSA in particular in pigs and farm workers in five states. We collected nasal swabs from pigs and farm workers at 45 swine herds (21 antibiotic-free herds; 24 conventional herds in Illinois, Iowa, Minnesota, North Carolina and Ohio. MRSA was isolated from 50 of 1085 pigs (4.6% and 31 of 148 (20.9% of farm workers. MRSA-positive pigs and people were clustered in four conventional swine farms in Iowa and Illinois. Based on genotyping, spa type t034, a common livestock associated variant, was predominant among both human and swine isolates. These results confirm the presence of LA-MRSA in pigs and swine farm workers in the USA, but the prevalence found is relatively low compared with European studies.

The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Hamza Ameer

2016-01-01

Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

The emerging ST8 methicillin-resistant Staphylococcus aureus clone in the community in Japan: associated infections, genetic diversity, and comparative genomics.

Science.gov (United States)

Iwao, Yasuhisa; Ishii, Rumiko; Tomita, Yusuke; Shibuya, Yasuhiro; Takano, Tomomi; Hung, Wei-Chun; Higuchi, Wataru; Isobe, Hirokazu; Nishiyama, Akihito; Yano, Mio; Matsumoto, Tetsuya; Ogata, Kikuyo; Okubo, Takeshi; Khokhlova, Olga; Ho, Pak-Leung; Yamamoto, Tatsuo

2012-04-01

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIVl (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jβ was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention.

Molecular Studies on Methicillin-Resistant Staphylococcus aureus

International Nuclear Information System (INIS)

Tawfik, Z.S.; Mohamed, H.A.; Abu Shady, H.M.; Abu Shady, M.R.

2011-01-01

The present study of the MecA gene in our clinical isolates has been detected and verified by antibiotic disc diffusion test and nested Polymerase Chain Reaction (PCR). Part of the product of the second PCR was also sequenced. The results indicated 97.7% similarity between the sequences of the mecA gene isolated from an Egyptian Staphylococcus aureus strain and that compared from Staphylococcus aureus strain no. GI46628 cited at the European Molecular Biology Laboratory (EMBL) database under accession number Y00688 in the region from nucleotide 467 to 875. The effect of gamma-radiation on these isolates was observed by plotting the dose survival curves of these isolates and determining their D10 values. Their D10 values were found to be ranged from 0.44 to 0.66 kGy. Antibiotic sensitivity tests were also carried out after exposure of Oxacillin-susceptible isolate to sub -lethal doses of γ-radiation.Results indicated that Staphylococcus aureus isolates which were sensitive to oxacillin discs were found by PCR to harbor the mecA gene in their genomes. Also, exposure of a sensitive isolate to sublethal doses of gamma radiation led to the emergence of a oxacillin-resistant variant which could be a serious problem in case of using sub-lethal doses of radiation for the sterilization of medical products

Staphylococcus aureus enterotoxins A- and B

DEFF Research Database (Denmark)

Danielsen, E Michael; Hansen, Gert H; Karlsdóttir, Edda

2013-01-01

Enterotoxins of Staphylococcus aureus are among the most common causes of food poisoning. Acting as superantigens they intoxicate the organism by causing a massive uncontrolled T cell activation that ultimately may lead to toxic shock and death. In contrast to our detailed knowledge regarding...

Nasal carriage of multi-drug resistant Staphylococcus aureus in ...

African Journals Online (AJOL)

Background: Nasal Staphylococcus aureus is a major source of community and hospital associated staphylococcal infections. This study determined the prevalence of nasal S. aureus isolates and investigated their antimicrobial resistance profile in healthy volunteers. Methods: Nasal specimens of healthy volunteers in ...

A pig model of acute Staphylococcus aureus induced pyemia

DEFF Research Database (Denmark)

Nielsen, O. L.; Iburg, T.; Aalbæk, B.

2009-01-01

Background: Sepsis caused by Staphylococcus aureus constitutes an important cause of morbidity and mortality in humans, and the incidence of this disease-entity is increasing. In this paper we describe the initial microbial dynamics and lesions in pigs experimentally infected with S. aureus....... aureus isolated from man and an extension of the timeframe aiming at inducing sepsis, severe sepsis and septic shock....

Staphylococcus aureus CC398

DEFF Research Database (Denmark)

Price, Lance B.; Stegger, Marc; Hasman, Henrik

2012-01-01

Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collection...... of CC398 isolates (n = 89), including MRSA and methicillin-susceptible S. aureus (MSSA) from animals and humans spanning 19 countries and four continents. We identified 4,238 single nucleotide polymorphisms (SNPs) among the 89 core genomes. Minimal homoplasy (consistency index = 0.9591) was detected...... among parsimony-informative SNPs, allowing for the generation of a highly accurate phylogenetic reconstruction of the CC398 clonal lineage. Phylogenetic analyses revealed that MSSA from humans formed the most ancestral clades. The most derived lineages were composed predominantly of livestock...

Staphylococcus aureus and the ecology of the nasal microbiome

DEFF Research Database (Denmark)

Liu, Cindy M; Price, Lance B; Hungate, Bruce A

2015-01-01

The human microbiome can play a key role in host susceptibility to pathogens, including in the nasal cavity, a site favored by Staphylococcus aureus. However, what determines our resident nasal microbiota-the host or the environment-and can interactions among nasal bacteria determine S. aureus...

Staphylococcus aureus and Staphylococcus epidermidis strain diversity underlying pediatric atopic dermatitis.

Science.gov (United States)

Byrd, Allyson L; Deming, Clay; Cassidy, Sara K B; Harrison, Oliver J; Ng, Weng-Ian; Conlan, Sean; Belkaid, Yasmine; Segre, Julia A; Kong, Heidi H

2017-07-05

The heterogeneous course, severity, and treatment responses among patients with atopic dermatitis (AD; eczema) highlight the complexity of this multifactorial disease. Prior studies have used traditional typing methods on cultivated isolates or sequenced a bacterial marker gene to study the skin microbial communities of AD patients. Shotgun metagenomic sequence analysis provides much greater resolution, elucidating multiple levels of microbial community assembly ranging from kingdom to species and strain-level diversification. We analyzed microbial temporal dynamics from a cohort of pediatric AD patients sampled throughout the disease course. Species-level investigation of AD flares showed greater Staphylococcus aureus predominance in patients with more severe disease and Staphylococcus epidermidis predominance in patients with less severe disease. At the strain level, metagenomic sequencing analyses demonstrated clonal S. aureus strains in more severe patients and heterogeneous S. epidermidis strain communities in all patients. To investigate strain-level biological effects of S. aureus , we topically colonized mice with human strains isolated from AD patients and controls. This cutaneous colonization model demonstrated S. aureus strain-specific differences in eliciting skin inflammation and immune signatures characteristic of AD patients. Specifically, S. aureus isolates from AD patients with more severe flares induced epidermal thickening and expansion of cutaneous T helper 2 (T H 2) and T H 17 cells. Integrating high-resolution sequencing, culturing, and animal models demonstrated how functional differences of staphylococcal strains may contribute to the complexity of AD disease. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923.

Science.gov (United States)

Treangen, Todd J; Maybank, Rosslyn A; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F; Karaolis, David K R; Koren, Sergey; Ondov, Brian; Phillippy, Adam M; Bergman, Nicholas H; Rosovitz, M J

2014-11-06

Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid. Copyright © 2014 Treangen et al.

Kemampuan Daya Hambat Bahan Aktif Beberapa Merek Dagang Hand sanitizer terhadap Pertumbuhan Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Putri Srikartika

2016-09-01

Full Text Available AbstrakHand sanitizer sebagai pembersih tangan antiseptik inovatif saat ini, sering menjadi alternatif pengganti cuci tangan dengan sabun dan air. Mencuci tangan dengan hand sanitizer merupakan salah satu cara memelihara kebersihan tangan agar terhindar dari penyakit  yang disebabkan oleh flora normal di kulit yang berpotensi patogenik seperti bakteri Staphylococcus aureus. Tujuan penelitian ini adalah menilai kemampuan daya hambat beberapa merek dagang hand sanitizer terhadap pertumbuhan Staphylococcus aureus. Penelitian dilakukan dengan metode rancangan acak lengkap pada empat macam hand sanitizer dengan tiga kali pengulangan. Data diolah secara manual dan menggunakan analisis varians (ANOVA dilanjutkan dengan uji pos-hoc dengan Tukey HSD dan independent t test. Hasil penelitian menunjukkan bahwa bahan aktif hand sanitizer mampu mengurangi pertumbuhan Staphylococcus aureus secara signifikan. Perbedaan prosentase rerata pengurangan jumlah koloni pada waktu 30 detik berkisar antara 57,65%-72,45%, sedangkan pada waktu 1 menit berkisar 67,88%-82,65%. Hasil analisis menunjukkan perbedaan bermakna terhadap perlakuan, antar perlakuan dan waktu yang diujikan dengan nilai signifikasi p <0,05. Didapatkan hand sanitizer lebih efektif menghambat pertumbuhan pada waktu 1 menit daripada 30 detik. Hand sanitizer yang mengandung alkohol 70% dan triklosan 0,05% memiliki kemampuan daya hambat lebih baik terhadap pertumbuhan Staphylococcus aureus.Kata kunci: bahan aktif, hand sanitizer, Staphylococcus aureus AbstractHand sanitizer is one of the ways for maintaining the hand hygiene. Hand sanitizer as an innovative antiseptic product at this time, becomes an alternative hand washing with soap and water. It prevents  the disease that can be caused by normal flora that potentially pathogenic bacterium such as Staphylococcus aureus. The objective of this study was to evaluate the inhibition ability of several trademarks hand sanitizer on the growth of

The impact of meticillin-resistant Staphylococcus aureus on patients with advanced cancer and their family members: A qualitative study.

Science.gov (United States)

Gleeson, Aoife; Larkin, Philip; O'Sullivan, Niamh

2016-04-01

Little is known about the impact of meticillin-resistant Staphylococcus aureus on patients with advanced cancer, such as its impact on the quality of life of this vulnerable group. To date, research on meticillin-resistant Staphylococcus aureus in the palliative care setting has had a quantitative focus. The purpose of this study was to explore the impact of a meticillin-resistant Staphylococcus aureus diagnosis on patients and their carers. This article reports upon a qualitative interview study of nine patients with advanced cancer and meticillin-resistant Staphylococcus aureus and nine family members (n = 18). Framework analysis was used to analyse the data. Patients and family members of patients with advanced cancer either admitted to the specialist palliative care unit or receiving palliative care in the hospital setting, who had a laboratory confirmed diagnosis of meticillin-resistant Staphylococcus aureus colonisation, were considered for inclusion in the study. Four themes were identified using framework analysis: reactions to receiving a meticillin-resistant Staphylococcus aureus diagnosis, the need for effective communication of the meticillin-resistant Staphylococcus aureus diagnosis, the enigmatic nature of meticillin-resistant Staphylococcus aureus, and lessons to guide the future care of meticillin-resistant Staphylococcus aureus patients. This article indicates that meticillin-resistant Staphylococcus aureus can have a significant impact on advanced cancer patients and their families. This impact may be underestimated, but early and careful face-to-face explanation about meticillin-resistant Staphylococcus aureus and its implications can help patients and their families to cope better with it. These findings should be considered when developing policy relating to meticillin-resistant Staphylococcus aureus management and infection control in specialist palliative care settings. © The Author(s) 2015.

Antibiotic resistant Staphylococcus aureus in Abia State of Nigeria ...

African Journals Online (AJOL)

The S. aureus. isolates varied in their antibiotic susceptibility pattern when tested for their sensitivity to 16 antibiotics. Eighty percent of the isolates were resistant to more than one antimicrobial agent. All the isolates showed resistance to nalidixic acid and 100% sensitivity to rifampicin. Key words: Staphylococcus aureus, ...

Photodynamic Action of LED-Activated Curcumin against Staphylococcus aureus Involving Intracellular ROS Increase and Membrane Damage

Directory of Open Access Journals (Sweden)

Yuan Jiang

2014-01-01

Full Text Available Aim. To investigate the effect of photodynamic action of LED-activated curcumin on cell viability, membrane permeability, and intracellular reactive oxygen species of Staphylococcus aureus. Methods. Staphylococcus aureus was incubated with the different concentrations of curcumin for 60 min and then irradiated by blue light with the wavelength of 470 nm and with light dose of 3 J/cm2. The colony forming unit assay was used to investigate photocytotoxicity of curcumin on Staphylococcus aureus, confocal laser scanning microscopy (CLSM and flow cytometry (FCM for assaying membrane permeability, FCM analysis with DCFH-DA staining for measuring the intracellular ROS level, and transmission electron microscopy (TEM for observing morphology and structure. Results. Blue light-activated curcumin significantly killed Staphylococcus aureus in a curcumin dose-dependent manner. TEM observed remarkable structural damages in S. aureus after light-activated curcumin. More red fluorescence of PI dye was found in S. aureus treated by blue light-activated curcumin than in those of the controlled bacterial cells. Intracellular ROS increase was observed after light-activated curcumin. Conclusion. Blue light-activated curcumin markedly damaged membrane permeability, resulting in cell death of Staphylococcus aureus and highlighted that intracellular ROS increase might be an important event in photodynamic killing of Staphylococcus aureus in the presence of curcumin.

Staphylococcus aureus but not Listeria monocytogenes adapt to triclosan and adaptation correlates with increased fabI expression and agr deficiency

DEFF Research Database (Denmark)

Nielsen, Lene Nørby; Larsen, Marianne Halberg; Skovgaard, Sissel

2013-01-01

was initially 4 mg/L and remained unaltered by the exposure. The adapted S. aureus isolates retained normal colony size but displayed increased expression of fabI encoding an essential enzyme in bacterial fatty acid synthesis. Also, they displayed decreased or no expression of the virulence associated agr......C of the agr quorum sensing system. While most adapted strains of USA300 carried mutations in fabI, none of the adapted strains of 8325-4 did. Conclusions. Adaptability to triclosan varies substantially between Gram positive human pathogens. S. aureus displayed an intrinsically lower MIC for triclosan compared...... to L. monocytogenes but was easily adapted leading to the same MIC as L. monocytogenes. Even though all adapted S. aureus strains over-expressed fabI and eliminated expression of the agr quorum sensing system, adaptation in USA300 involved fabI mutations whereas this was not the case for 8325-4. Thus...

Research advance in rapid detection of foodborne Staphylococcus aureus

OpenAIRE

Xihong Zhao; Caijiao Wei; Junliang Zhong; Shiwei Jin

2016-01-01

Staphylococcus aureus is a gram-positive, coccus-shaped facultative anaerobe and a member of the Staphylococcaceae family. In recent years, alimentary toxicosis caused by S. aureus is a very serious problem worldwide, which constitutes a great threat to public health. In this review, we tried to summarize the conventional methods and newly developed rapid detection techniques of S. aureus (traditional detection method, biochemical detection, immunology method, molecular biology, and biosensor...

UJI KEBERADAAN Staphylococcus aureus PADA SOSIS TRADISIONAL (URUTAN YANG BEREDAR DI PASAR TRADISIONAL DI DENPASAR, BALI

Directory of Open Access Journals (Sweden)

Ni Putu Niti Rahayu

2014-07-01

Full Text Available The aim of this study is to determine the total amount of Staphylococcus aureus in atraditional sausage (urutan sold in Denpasar traditional market in Bali. Sausage samples aretaken from four areas in Denpasar (North Denpasar, East Denpasar, West Denpasar, and SouthDenpasar. From each area, three traditional markets are selected and from each market 2merchants are chosen. The calculation of the number of Staphylococcus aureus is done byplatting method and by pour plate method. The results show that the highest number ofStaphylococcus aureus belongs to the North Denpasar region in the mount of 241,067 CFU/gwhile the lowest belongs to the region of West Denpasar with 71,233 CFU/g. These two resultsare significantly different with one another (P<0,05. The maximum limit of microbialcontamination in processed meats (sausages for Staphylococcus aureus based on IndonesianNational Standard (SNI is equal to 102 CFU / g. Based on the testing that has been done, allurutan contamination by the Staphylococcus aureus in Denpasar traditional market, hasexceeded the threshold amount of SNI.Keywords : Traditional Sausages (urutan, Staphylococcus aureus

Mode of action of Buddleja cordata verbascoside against Staphylococcus aureus.

Science.gov (United States)

Avila, J G; de Liverant, J G; Martínez, A; Martínez, G; Muñoz, J L; Arciniegas, A; Romo de Vivar, A

1999-07-01

We evaluate the mode of action of verbascoside obtained from Buddleja cordata against Staphylococcus aureus by killing kinetics and incorporation of precursors methods. Verbascoside induced lethal effect on S. aureus, by affecting protein synthesis and inhibiting leucine incorporation.

Comparison of multi-drug resistant environmental methicillin-resistant Staphylococcus aureus [MRSA] isolated from recreational beaches and high touch surfaces in built environments

Directory of Open Access Journals (Sweden)

Marilyn C Roberts

2013-04-01

Full Text Available Over the last decade community-acquired methicillin-resistant Staphylococcus aureus [MRSA] has emerged as a major cause of disease in the general population with no health care exposure or known classical risk factors for MRSA infections. The potential community reservoirs have not been well defined though certain strains such as ST398 and USA300 have been well studied in some settings. MRSA has been isolated from recreational beaches, high-touch surfaces in homes, universities and other community environmental surfaces. However, in most cases the strains were not characterized to determine if they are related to community-acquired or hospital-acquired clinical strains. We compared 55 environmental MRSA from 805 samples including sand, fresh and marine water samples from local marine and fresh water recreational beaches (n=296, high touch surfaces on the University of Washington campus (n=294, surfaces in UW undergraduate housing (n=85, and the local community (n=130. Eleven USA300, representing 20% of the isolates, were found on the UW campus surfaces, student housing surfaces and on the community surfaces but not in the recreational beach samples from the Northwest USA. Similarly, the predominant animal ST133 was found in the recreational beach samples but not in the high touch surface samples. All USA300 isolates were multi-drug resistant carrying 2-6 different antibiotic resistance genes coding for kanamycin, macrolides and/or macrolides-lincosamides-streptogramin B and tetracycline, with the majority [72%] carrying 4-6 different antibiotic resistance genes. A surprising 98% of the 55 MRSA isolates were resistant to other classes of antibiotics and most likely represent reservoirs for these genes in the environment.

Presence of Methicillin Resistant Staphylococcus aureus (MRSA) in sewage treatment plant.

Science.gov (United States)

Boopathy, Raj

2017-09-01

The presence of antibiotic resistant bacteria and antibiotic resistance genes in rural sewage treatment plants are not well reported in the literature. The aim of the present study was to study the frequency occurrence of Methicillin Resistant Staphylococcus aureus (MRSA) in a rural sewage treatment plant. This study was conducted using raw sewage as well as treated sewage from a small town sewage treatment plant in rural southeast Louisiana of USA. Results showed the presence of MRSA consistently in both raw and treated sewage. The presence of mecA gene responsible for methicillin resistance was confirmed in the raw and treated sewage water samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Meticillineresistente Staphylococcus aureus (MRSA) in de gemeenschap

NARCIS (Netherlands)

Vonk, A. G.; Vandenbroucke-Grauls, C. M. J. E.

2007-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) infections have been confined to healthcare centres for decades. However, MRSA infections are increasingly seen in young healthy individuals with no exposure to healthcare centres. These community-acquired MRSA (CA-MRSA) strains differ from

Left-sided native valve Staphylococcus aureus endocarditis

NARCIS (Netherlands)

Slabbekoorn, M.; Horlings, H. M.; van der Meer, J. T. M.; Windhausen, A.; Van der Sloot, J. A. P.; Lagrand, W. K.

2010-01-01

Despite improved diagnostic tools and expanded treatment options, left-sided native valve endocarditis caused by Staphylococcus aureus infection remains a serious and destructive disease. The high morbidity and mortality, however, can be reduced by early recognition, correct diagnosis, and

Prevalence of methicillin-resistant Staphylococcus aureus and ...

African Journals Online (AJOL)

Wound colonization by microorganisms is most frequently polymicrobial and incidences of high level resistance among bacterial isolates from wounds have been reported. Methicillin-resistant Staphylococcus aureus (MRSA) and extendedspectrum beta-lactamase (ESBL) producing Gram-negative bacteria both constitute ...

Diversity of Staphylococcus aureus Isolates in European Wildlife

Science.gov (United States)

Monecke, Stefan; Gavier-Widén, Dolores; Hotzel, Helmut; Peters, Martin; Guenther, Sebastian; Lazaris, Alexandros; Loncaric, Igor; Müller, Elke; Reissig, Annett; Ruppelt-Lorz, Antje; Shore, Anna C.; Walter, Birgit; Coleman, David C.; Ehricht, Ralf

2016-01-01

Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST). The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963) were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation. PMID:27992523

Nasal Carriage Rate of Methicillin Resistant Staphylococcus aureus among Health Care Workers at a Tertiary Care Hospital in Kathmandu, Nepal.

Science.gov (United States)

Khatri, S; Pant, N D; Bhandari, R; Shrestha, K L; Shrestha, C D; Adhikari, N; Poudel, A

2017-01-01

Methicillin-resistant Staphylococcus aureus is one of the most common causes of nosocomial infections. Due to its multidrug resistant nature; infections due to Methicillin-resistant Staphylococcus aureus are often very difficult to treat. Colonized health care workers are the important sources of Methicillin-resistant Staphylococcus aureus. The objectives of this study were to determine the nasal carriage rate of Methicillin-resistant Staphylococcus aureus among health care workers at Kathmandu Medical College and Teaching Hospital, Nepal and to assess their antimicrobial susceptibility patterns. A cross sectional study was conducted among 252 health care workers from July to November 2013. Mannitol salt agar was used to culture the nasal swabs. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion technique following Clinical and Laboratory Standards Institute guidelines. Methicillin-resistant Staphylococcus aureus strains were confirmed by using cefoxitin disc and by determining the minimum inhibitory concentration of oxacillin by agar dilution method. Of 252 healthcare workers, 46(18.3%) were positive for Staphylococcus aureus among which 19(41.3%) were Methicillin-resistant Staphylococcus aureus carriers. Overall rate of nasal carriage of Methicillin-resistant Staphylococcus aureus was 7.5% (19/252).The higher percentages of lab personnel were nasal carriers of S. aureus (31.6%) and Methicillin-resistant Staphylococcus aureus (10.5%).The percentages of nasal carriage of S. aureus (35.7%) and Methicillin-resistant Staphylococcus aureus (14.3%) were highest in the health care workers from post operative department. Higher percentage of Methicillin-resistant Staphylococcus aureus were susceptible toward amikacin (100%) and vancomycin (100%) followed by cotrimoxazole (84.2%). High rates of nasal carriage of S. aureus and Methicillin-resistant Staphylococcus aureus were observed among the healthcare workers, which indicate the need of

Methicillin-resistant Staphylococcus aureus prevention strategies in the ICU: a clinical decision analysis*.

Science.gov (United States)

Ziakas, Panayiotis D; Zacharioudakis, Ioannis M; Zervou, Fainareti N; Mylonakis, Eleftherios

2015-02-01

ICUs are a major reservoir of methicillin-resistant Staphylococcus aureus. Our aim was to estimate costs and effectiveness of methicillin-resistant Staphylococcus aureus prevention policies. We evaluated three up-to-date methicillin-resistant Staphylococcus aureus prevention policies, namely, 1) nasal screening and contact precautions of methicillin-resistant Staphylococcus aureus-positive patients; 2) nasal screening, contact precautions, and decolonization (targeted decolonization) of methicillin-resistant Staphylococcus aureus carriers; and 3) universal decolonization without screening. We implemented a decision-analytic model with deterministic and probabilistic analyses. Methicillin-resistant Staphylococcus aureus infections averted, quality-adjusted life years gained, and incremental cost-effectiveness ratios were calculated. Cost-effectiveness planes and acceptability curves were plotted for various willingness-to-pay thresholds to address uncertainty. At base-case scenario, universal decolonization was the dominant strategy; it averted 1.31% and 1.59% of methicillin-resistant Staphylococcus aureus infections over targeted decolonization and screening and contact precautions, respectively, and saved $16,203/quality-adjusted life year over targeted decolonization and 14,562/quality-adjusted life year over screening and contact precautions. Results were robust in sensitivity analysis for a wide range of input variables. In probabilistic analysis, universal decolonization increased quality-adjusted life years by 1.06% (95% CI, 1.02-1.09) over targeted decolonization and by 1.29% (95% CI, 1.24-1.33) over screening and contact precautions; universal decolonization resulted in average savings of $172 (95% CI, $168-$175) and $189 (95% CI, $185-$193) over targeted decolonization and screening and contact precautions, respectively. With willingness-to-pay threshold per quality-adjusted life year gained ranging from $0 to $50,000, universal decolonization was dominant

Staphylococcus aureus spa type t437

DEFF Research Database (Denmark)

Glasner, C; Pluister, G; Westh, H

2015-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) belonging to the multilocus sequence type clonal complex 59 (MLST CC59) is the predominant community-associated MRSA clone in Asia. This clone, which is primarily linked with the spa type t437, has so far only been reported in low numbers among...... included. Most isolates were shown to be monophyletic with 98% of the isolates belonging to the single MLVA complex 621, to which nearly all included isolates from China also belonged. More importantly, all MLST-typed isolates belonged to CC59. Our study implies that the European S. aureus t437 population...

Staphylococcus aureus ST398 from slaughter pigs in northeast China

NARCIS (Netherlands)

Yan, Xiaomei; Yu, Xiaojie; Tao, Xiaoxia; Zhang, Jianfeng; Zhang, Binghua; Dong, Rui; Xue, Chengyu; Grundmann, Hajo; Zhang, Jianzhong

To describe the prevalence and population structure of Staphylococcus aureus bacteria that colonize pigs at slaughterhouses in northeastern China, nose swabs were collected from pigs in two slaughterhouses in Harbin, Heilongjiang Province, China in 2009.S. aureus isolates were characterized by

Comparison of five tests for identification of Staphylococcus aureus from clinical samples

NARCIS (Netherlands)

A. Luijendijk (Ad); A.F. van Belkum (Alex); J.A.J.W. Kluytmans (Jan); H.A. Verbrugh (Henri)

1996-01-01

textabstractFive different laboratory tests for the identification of Staphylococcus aureus were compared. Analyses of 271 presumptive S. aureus strains, supplemented with 59 well-defined methicillin-resistant S. aureus (MRSA) isolates, were performed. Only the

Relationship between Vancomycin-Resistant Staphylococcus aureus, Vancomycin-Intermediate S. aureus, High Vancomycin MIC, and Outcome in Serious S. aureus Infections

OpenAIRE

Holmes, Natasha E.; Johnson, Paul D. R.; Howden, Benjamin P.

2012-01-01

Vancomycin has been used successfully for over 50 years for the treatment of Staphylococcus aureus infections, particularly those involving methicillin-resistant S. aureus. It has proven remarkably reliable, but its efficacy is now being questioned with the emergence of strains of S. aureus that display heteroresistance, intermediate resistance, and, occasionally, complete vancomycin resistance. More recently, an association has been established between poor outcome and infections with strain...

Simple method for correct enumeration of Staphylococcus aureus

DEFF Research Database (Denmark)

Haaber, J.; Cohn, M. T.; Petersen, A.

2016-01-01

culture. When grown in such liquid cultures, the human pathogen Staphylococcus aureus is characterized by its aggregation of single cells into clusters of variable size. Here, we show that aggregation during growth in the laboratory standard medium tryptic soy broth (TSB) is common among clinical...... and laboratory S. aureus isolates and that aggregation may introduce significant bias when applying standard enumeration methods on S. aureus growing in laboratory batch cultures. We provide a simple and efficient sonication procedure, which can be applied prior to optical density measurements to give...

Computational structural and functional analysis of hypothetical proteins of Staphylococcus aureus

OpenAIRE

Mohan, Ramadevi; Venugopal, Subhashree

2012-01-01

Genome sequencing projects has led to an explosion of large amount of gene products in which many are of hypothetical proteins with unknown function. Analyzing and annotating the functions of hypothetical proteins is important in Staphylococcus aureus which is a pathogenic bacterium that cause multiple types of diseases by infecting various sites in humans and animals. In this study, ten hypothetical proteins of Staphylococcus aureus were retrieved from NCBI and analyzed for their structural ...

Treatment of methicillin-resistant Staphylococcus aureus in Latin America Tratamento de Staphylococcus aureus resistente à meticilina na América Latina

Directory of Open Access Journals (Sweden)

Carlos M Luna

2010-12-01

Full Text Available The global spread of methicillin-resistant Staphylococcus aureus (MRSA means it is now a pathogen of worldwide public health concern. Within Latin America, MRSA is highly prevalent, with the proportion of S. aureus isolates that are methicillin-resistant on the rise, yet resources for managing the infection are limited. While several guidelines exist for the treatment of MRSA infections, many are written for the North American or European setting and need adaptation for use in Latin America. In this article, we aim to emphasize the importance of appropriate treatment of MRSA in the healthcare and community settings of Latin America. We present a summary of the available guidelines and antibiotics, and discuss particular considerations for clinicians treating MRSA in Latin AmericaA propagação global de Staphylococcus aureus resistente à meticilina (methicillin-resistant Staphylococcus aureus - MRSA significa que se trata agora de um patógeno de interesse para a saúde pública mundial. Na América Latina, o MRSA é altamente prevalente, com a proporção de S. aureus resistente à meticilina em ascensão, no entanto os recursos para o tratamento da infecção são limitados. Embora existam várias diretrizes para o tratamento de infecções por MRSA, muitas são elaboradas para a América do Norte ou a Europa e precisam ser adaptadas para sua utilização na América Latina. Neste artigo, procuramos destacar a importância do tratamento adequado do MRSA nas unidades de saúde e na comunidade na América Latina. Apresentamos um resumo das diretrizes e dos antibióticos disponíveis, e discutimos considerações específicas para os médicos que tratam de MRSA na América Latina.

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

Induction of type I interferon signaling determines the relative pathogenicity of Staphylococcus aureus strains.

Directory of Open Access Journals (Sweden)

Dane Parker

2014-02-01

Full Text Available The tremendous success of S. aureus as a human pathogen has been explained primarily by its array of virulence factors that enable the organism to evade host immunity. Perhaps equally important, but less well understood, is the importance of the intensity of the host response in determining the extent of pathology induced by S. aureus infection, particularly in the pathogenesis of pneumonia. We compared the pathogenesis of infection caused by two phylogenetically and epidemiologically distinct strains of S. aureus whose behavior in humans has been well characterized. Induction of the type I IFN cascade by strain 502A, due to a NOD2-IRF5 pathway, was the major factor in causing severe pneumonia and death in a murine model of pneumonia and was associated with autolysis and release of peptidogylcan. In contrast to USA300, 502A was readily eliminated from epithelial surfaces in vitro. Nonetheless, 502A caused significantly increased tissue damage due to the organisms that were able to invade systemically and trigger type I IFN responses, and this was ameliorated in Ifnar⁻/⁻ mice. The success of USA300 to cause invasive infection appears to depend upon its resistance to eradication from epithelial surfaces, but not production of specific toxins. Our studies illustrate the important and highly variable role of type I IFN signaling within a species and suggest that targeted immunomodulation of specific innate immune signaling cascades may be useful to prevent the excessive morbidity associated with S. aureus pneumonia.

Research advance in rapid detection of foodborne Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Xihong Zhao

2016-09-01

Full Text Available Staphylococcus aureus is a gram-positive, coccus-shaped facultative anaerobe and a member of the Staphylococcaceae family. In recent years, alimentary toxicosis caused by S. aureus is a very serious problem worldwide, which constitutes a great threat to public health. In this review, we tried to summarize the conventional methods and newly developed rapid detection techniques of S. aureus (traditional detection method, biochemical detection, immunology method, molecular biology, and biosensor method for their principles, advantages, disadvantages, and applications. Furthermore, the future perspectives of S. aureus detection methods were forecasted at last.

Detection and identification of Staphylococcus aureus in raw milk by ...

African Journals Online (AJOL)

Staphylococcus aureus causes foodborne diseases if consumed in contaminated milk products. Rapid detection and characterization of foodborne pathogen S. aureus is crucial for epidemiological investigations and food safety surveillance. It is still a challenge to detect and identify bacterial pathogens quickly and ...

Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

Directory of Open Access Journals (Sweden)

Kaur M

2015-10-01

Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

In vitro phagocytosis of methicillin resistant and methicillin sensitive staphylococcus aureus by human polymorphonuclear leucocytes

International Nuclear Information System (INIS)

Javed, N.; Tahir, R.; Abbas, A.

2009-01-01

Staphylococcus aureus is a gram positive bacterium that causes a number of diseases such as abscesses, infective endocarditis, septic arthritis, etc. It is acquiring resistance against many antibiotics like methicillin; therefore its control is becoming increasingly difficult. Peripheral blood phagocytes particularly polymorphonuclear leucocytes play an important role in the protective mechanisms against these organisms. Phagocytes interact with bacteria and phagocytose these microorganisms to kill them. Phenotypically different isolates of Staphylococcus aureus including methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive Staphylococcus aureus (MSSA) were collected from various hospitals of Lahore, Pakistan. Fresh polymorphonuclaer leucocytes were obtained from healthy individuals by centrifugation using Ficol-Hypaque gradient combined with dextran sedimentation. Microbiological method was used for the determination of phagocytic index of phenotypic variants of Staphylococcus aureus. A significant difference was observed between the phagocytic index of both bacterial groups. MSSA group showed the Mean+-SD of 79.46%+-3.9 while MRSA group showed 72.35%+-2.5. Significant difference in phagocytic index indicates that it can be one of the mechanisms of MRSA to evade host immune system as compare to MSSA. (author)

Investigation of the potential for mutational resistance to XF-73, retapamulin, mupirocin, fusidic acid, daptomycin, and vancomycin in methicillin-resistant Staphylococcus aureus isolates during a 55-passage study.

Science.gov (United States)

Farrell, David J; Robbins, Marion; Rhys-Williams, William; Love, William G

2011-03-01

XF-73 is a dicationic porphyrin drug with rapid Gram-positive antibacterial activity currently undergoing clinical trials for the nasal decolonization of Staphylococcus aureus, including methicillin-resistant Staphylococcus aureus (MRSA). In multistep (55-passage) resistance selection studies in the presence of subinhibitory concentrations of XF-73, retapamulin, mupirocin, fusidic acid, and vancomycin against four Network on Antimicrobial Resistance in Staphylococcus aureus MRSA strains, there was no >4-fold increase in the MIC for XF-73 after 55 passages. In contrast, there was an increase in the MICs for retapamulin (from 0.25 μg/ml to 4 to 8 μg/ml), for mupirocin (from 0.12 μg/ml to 16 to 512 μg/ml), for fusidic acid (from 0.12 μg/ml to 256 μg/ml), and for vancomycin (from 1 μg/ml to 8 μg/ml in two of the four strains tested). Further investigations using S. aureus NRS384 (USA300) and daptomycin demonstrated a 64-fold increase in the MIC after 55 passages (from 0.5 μg/ml to 32 μg/ml) with a >4-fold increase in the MIC obtained after only five passages. Sequencing analysis of selected isolates confirmed previously reported point mutations associated with daptomycin resistance. No cross-resistance to XF-73 was observed with the daptomycin-resistant strains, suggesting that whereas the two drugs act on the bacterial cell membrane, their specific site of action differs. XF-73 thus represents the first in a new class of antibacterial drugs, which (unlike the comparator antibiotics) after 55 passages exhibited a ≤4-fold increase in MIC against the strains tested. Antibacterial drugs with a low propensity for inducing bacterial resistance are much needed for the prevention and treatment of multidrug-resistant bacteria both within and outside the hospital setting.

Staphylococcus aureus bacteraemia in children: a formidable foe

African Journals Online (AJOL)

Staphylococcus aureus bacteraemia is a systemic disease; and, multiple organ involvement should be .... damage.3. Few studies have investigated the epidemiology of SAB in South ... producing a multitude of virulence factors, exotoxins and.

Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients

NARCIS (Netherlands)

Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W.

Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients.

Community-acquired methicillin-resistant Staphylococcus aureus: community transmission, pathogenesis, and drug resistance.

Science.gov (United States)

Yamamoto, Tatsuo; Nishiyama, Akihito; Takano, Tomomi; Yabe, Shizuka; Higuchi, Wataru; Razvina, Olga; Shi, Da

2010-08-01

Methicillin-resistant Staphylococcus aureus (MRSA) is able to persist not only in hospitals (with a high level of antimicrobial agent use) but also in the community (with a low level of antimicrobial agent use). The former is called hospital-acquired MRSA (HA-MRSA) and the latter community-acquired MRSA (CA-MRSA). It is believed MRSA clones are generated from S. aureus through insertion of the staphylococcal cassette chromosome mec (SCCmec), and outbreaks occur as they spread. Several worldwide and regional clones have been identified, and their epidemiological, clinical, and genetic characteristics have been described. CA-MRSA is likely able to survive in the community because of suitable SCCmec types (type IV or V), a clone-specific colonization/infection nature, toxin profiles (including Pantone-Valentine leucocidin, PVL), and narrow drug resistance patterns. CA-MRSA infections are generally seen in healthy children or young athletes, with unexpected cases of diseases, and also in elderly inpatients, occasionally surprising clinicians used to HA-MRSA infections. CA-MRSA spreads within families and close-contact groups or even through public transport, demonstrating transmission cores. Re-infection (including multifocal infection) frequently occurs, if the cores are not sought out and properly eradicated. Recently, attention has been given to CA-MRSA (USA300), which originated in the US, and is growing as HA-MRSA and also as a worldwide clone. CA-MRSA infection in influenza season has increasingly been noted as well. MRSA is also found in farm and companion animals, and has occasionally transferred to humans. As such, the epidemiological, clinical, and genetic behavior of CA-MRSA, a growing threat, is focused on in this study.

In silico analysis for identifying potential vaccine candidates against Staphylococcus aureus

OpenAIRE

Delfani, Somayeh; Imani Fooladi, Abbas Ali; Mobarez, Ashraf Mohabati; Emaneini, Mohammad; Amani, Jafar; Sedighian, Hamid

2015-01-01

Purpose Staphylococcus aureus is one of the most important causes of nosocomial and community-acquired infections. The increasing incidence of multiple antibiotic-resistant S. aureus strains and the emergence of vancomycin resistant S. aureus strains have placed renewed interest on alternative means of prevention and control of infection. S. aureus produces a variety of virulence factors, so a multi-subunit vaccine will be more successful for preventing S. aureus infections than a mono-subuni...

Elucidating the crucial role of poly N-acetylglucosamine from Staphylococcus aureus in cellular adhesion and pathogenesis.

Science.gov (United States)

Lin, Mei Hui; Shu, Jwu Ching; Lin, Li Ping; Chong, Kowit Yu; Cheng, Ya Wen; Du, Jia Fu; Liu, Shih-Tung

2015-01-01

Staphylococcus aureus is an important pathogen that forms biofilms on the surfaces of medical implants. Biofilm formation by S. aureus is associated with the production of poly N-acetylglucosamine (PNAG), also referred to as polysaccharide intercellular adhesin (PIA), which mediates bacterial adhesion, leading to the accumulation of bacteria on solid surfaces. This study shows that the ability of S. aureus SA113 to adhere to nasal epithelial cells is reduced after the deletion of the ica operon, which contains genes encoding PIA/PNAG synthesis. However, this ability is restored after a plasmid carrying the entire ica operon is transformed into the mutant strain, S. aureus SA113Δica, showing that the synthesis of PIA/PNAG is important for adhesion to epithelial cells. Additionally, S. carnosus TM300, which does not produce PIA/PNAG, forms a biofilm and adheres to epithelial cells after the bacteria are transformed with a PIA/PNAG-expressing plasmid, pTXicaADBC. The adhesion of S. carnosus TM300 to epithelial cells is also demonstrated by adding purified exopolysaccharide (EPS), which contains PIA/PNAG, to the bacteria. In addition, using a mouse model, we find that the abscess lesions and bacterial burden in lung tissues is higher in mice infected with S. aureus SA113 than in those infected with the mutant strain, S. aureus SA113Δica. The results indicate that PIA/PNAG promotes the adhesion of S. aureus to human nasal epithelial cells and lung infections in a mouse model. This study elucidates a mechanism that is important to the pathogenesis of S. aureus infections.

Nasal screening for Staphylococcus aureus--daily routine with improvement potentials.

Directory of Open Access Journals (Sweden)

Philipp Warnke

Full Text Available OBJECTIVES: Staphylococcus aureus causes purulent bacterial infections with a considerable number of life-threatening complications and thus, is a serious cost factor in public health. Up to 50% of a given population could asymptomatically carry Staphylococcus aureus in their nares, thereby serving as a source for contact transmissions and endogenous infections. Nasal swab-based screening techniques are widely used to identify suchcarriers. This study investigated the skill of medical professionals in taking nasal swabs and the effect of teaching on improving bacterial recovery rates. METHODS: 364 persons with different medical educational background participated in this study. A novel anatomically correct artificial nose model was implemented and inoculated with a numerically defined mixture of Staphylococcus aureus and Staphylococcus epidermidis bacteria. Utilizing regular clinical swabs, participants performed screening of the inoculated nose models before and after standardized theoretical, visual, and practical teaching. Recovery of bacteria was measured by standard viable count techniques. Data were analyzed statistically by nonparametric tests. RESULTS: It could be demonstrated that combined theoretical and practical teaching improved bacterial recovery rates. Even experienced medical professionals increased their detection levels after training. Recovery rates of bacteria varied significantly between trained (158.1 CFU and untrained (47.5 CFU participants (Wilcoxon test, p<0.001; Kolmogorov-Smirnov test, p<0.001. CONCLUSIONS: Swabs are commonly used to detect nasal carriage of Staphylococcus aureus in patients. The present teaching algorithm combined with the novel nose model offers an excellent precondition to improve knowledge and performance of this technique. Increased detection rates may prevent from contact transmission due to suboptimum hygienic patient handling. Consecutively, this effect could reduce costs for patient care. This

Distribution of capsular and surface polysaccharide serotypes of Staphylococcus aureus

NARCIS (Netherlands)

von Eiff, Christof; Taylor, Kimberly L; Mellmann, Alexander; Fattom, Ali I; Friedrich, Alexander W.; Peters, Georg; Becker, Karsten

Because of its ability to cause serious and fatal infections, Staphylococcus aureus remains one of the most feared microorganisms. Methicillin-resistant S. aureus (MRSA) has long been a common pathogen in healthcare facilities, but within the past decade, it has emerged as a problematic pathogen in

Retrospective study of necrotizing fasciitis and characterization of its associated Methicillin-resistant Staphylococcus aureus in Taiwan

Directory of Open Access Journals (Sweden)

Changchien Chih-Hsuan

2011-10-01

Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has emerged as a prevalent pathogen of necrotizing fasciitis (NF in Taiwan. A four-year NF cases and clinical and genetic differences between hospital acquired (HA- and community-acquired (CA-MRSA infection and isolates were investigated. Methods A retrospective study of 247 NF cases in 2004-2008 and antimicrobial susceptibilities, staphylococcal chromosomal cassette mec (SCCmec types, pulsed field gel electrophoresis (PFGE patterns, virulence factors, and multilocus sequence typing (MLST of 16 NF-associated MRSA in 2008 were also evaluated. Results In 247 cases, 42 microbial species were identified. S. aureus was the major prevalent pathogen and MRSA accounted for 19.8% of NF cases. Most patients had many coexisting medical conditions, including diabetes mellitus, followed by hypertension, chronic azotemia and chronic hepatic disease in order of decreasing prevalence. Patients with MRSA infection tended to have more severe clinical outcomes in terms of amputation rate (p S. aureus or non-S. aureus infection. NF patients infected by HA-MRSA had a significantly higher amputation rate, comorbidity, C-reactive protein level, and involvement of lower extremity than those infected by CA-MRSA. In addition to over 90% of MRSA resistant to erythromycin and clindamycin, HA-MRSA was more resistant than CA-MRSA to trimethoprim-sulfamethoxazole (45.8% vs. 4%. ST59/pulsotype C/SCCmec IV and ST239/pulsotype A/SCCmec III isolates were the most prevalent CA- and HA-MRSA, respectively in 16 isolates obtained in 2008. In contrast to the gene for γ-hemolysin found in all MRSA, the gene for Panton-Valentine leukocidin was only identified in ST59 MRSA isolates. Other three virulence factors TSST-1, ETA, and ETB were occasionally identified in MRSA isolates tested. Conclusion NF patients with MRSA infection, especially HA-MRSA infection, had more severe clinical outcomes than those infected by

Staphylococcus aureus Meticilina Resistente (MRSA e Infecções Nosocomiais

Directory of Open Access Journals (Sweden)

CRISTINA PAIVA SOUSA

2009-12-01

Full Text Available Um número crescente de cepas de Staphylococcus aureus meticilina resistente (MRSA apresentam resistência a múltiplos agentes antimicrobianos e são implicadas como causas de infecções hospitalares. S. aureus podem ser isolados de ambiente hospitalar e profissionais da saúde, revelando o risco de transmissão desses microrganismos pelo contato direto ou indireto com pacientes hospitalizados. Objetivou-se nesta revisão correlacionar este microrganismo com infecções hospitalares e avaliar as possíveis fontes de infecção, bem como enfatizar a importância do investimento em ações de educação em saúde que culminem em minimização de infecções hospitalares. Palavras-chave: Staphylococcus aureus meticilina resistente. Infecções nosocomiais.

[Sepsis with Staphylococcus aureus in immunocompromised patients].

Science.gov (United States)

Petrache, Simona Magdalena; Miftode, Egidia; Vâţă, A; Petrovici, Cristina Mirela; Dorneanu, Olivia; Luca, V

2009-01-01

The aim of our study was to analyze clinical and biological characteristics of immunocompromised patients with staphylococcal sepsis and to compare with the same data in non-immunocompromised patients. The diagnosis of sepsis was made based on Bone criteria. MiniAPI system ID 32 STAPH was used for identification and antibiotic susceptibility was assessed by ATB STAPH method and by E-test for oxacillin and vancomycin. Among the 147 patients with Staphylococcus aureus sepsis--66.67% had concomitant immunosuppressive conditions (diabetes mellitus, liver diseases, renal failure, corticotherapy, etc). We have found a significant correlation between the immunosuppressed status and MRSA (methicillin-resistant Staphylococcus aureus) involvement (p = 0.0018) and also, between this group of patients and treatment failure (p = 0.0012). Because of the high rate of MRSA involvement in systemic infections in the Eastern region of Romania first intention treatment of patients with staphylococcal infections and conditions of immunosuppression must include antibiotics effective against methicillin-resistant strains.

Expression of virulence factors by Staphylococcus aureus grown in serum.

Science.gov (United States)

Oogai, Yuichi; Matsuo, Miki; Hashimoto, Masahito; Kato, Fuminori; Sugai, Motoyuki; Komatsuzawa, Hitoshi

2011-11-01

Staphylococcus aureus produces many virulence factors, including toxins, immune-modulatory factors, and exoenzymes. Previous studies involving the analysis of virulence expression were mainly performed by in vitro experiments using bacterial medium. However, when S. aureus infects a host, the bacterial growth conditions are quite different from those in a medium, which may be related to the different expression of virulence factors in the host. In this study, we investigated the expression of virulence factors in S. aureus grown in calf serum. The expression of many virulence factors, including hemolysins, enterotoxins, proteases, and iron acquisition factors, was significantly increased compared with that in bacterial medium. In addition, the expression of RNA III, a global regulon for virulence expression, was significantly increased. This effect was partially restored by the addition of 300 μM FeCl₃ into serum, suggesting that iron depletion is associated with the increased expression of virulence factors in serum. In chemically defined medium without iron, a similar effect was observed. In a mutant with agr inactivated grown in serum, the expression of RNA III, psm, and sec4 was not increased, while other factors were still induced in the mutant, suggesting that another regulatory factor(s) is involved. In addition, we found that serum albumin is a major factor for the capture of free iron to prevent the supply of iron to bacteria grown in serum. These results indicate that S. aureus expresses virulence factors in adaptation to the host environment.

Streptokinase Treatment Reverses Biofilm-Associated Antibiotic Resistance in Staphylococcus aureus

DEFF Research Database (Denmark)

Jørgensen, Nis Pedersen; Zobek, Natalia; Dreier, Cindy

2016-01-01

by combining antibiotic treatment with a fibrinolytic drug. We quantified S. aureus USA300 biofilms grown on peg-lids in brain heart infusion (BHI) broth with 0%–50% human plasma. Young (2 h) and mature (24 h) biofilms were then treated with streptokinase to determine if this lead to dispersal. Then......, the minimal biofilm eradication concentration (MBEC) of 24 h old biofilms was measured for vancomycin and daptomycin alone or in combination with 10 µg/mL rifampicin in the presence or absence of streptokinase in the antibiotic treatment step. Finally, biofilms were visualized by confocal laser scanning...... or daptomycin, which are commonly used antibiotics for treatment of S. aureus infections. Fibronolytic drugs have been used to treat thromboembolic events for decades, and our findings suggest that their use against biofilm infections has the potential to improve the efficacy of antibiotics in treatment of S...

Frequency and Treatment of Methicillin Resistant Staphylococcus aureus in Obstetric and Gynaecological Sepsis

International Nuclear Information System (INIS)

Butt, I.J.; Khan, S.; Bhutta, S.; Butt, S.

2013-01-01

Objective: To perform culture and sensitivity for pathogens causing puerperal and postoperative wound sepsis and determine the frequency of Methicillin Resistant Staphylococcus aureus (MRSA) in such infections. Study Design: Observational study. Place and Duration of Study: Obstetrics and Gynaecology Ward, Jinnah Postgraduate Medical Centre, Karachi, from December 2008 to May 2010. Methodology: All patients presenting with puerperal sepsis or postoperative wound infection were enrolled. Pus was collected for culture and sensitivity using standard technique. Two samples were taken from each patient; one before starting the treatment and one at the end of treatment. Ames transport medium was used. Empirical treatment with triple regimen (Ampicillin, Metronidazole and Gentamicin) was started immediately to cover Gram positive as well as negative bacteria in addition to anaerobic infection. After receiving the sensitivity report, antimicrobial agent were changed accordingly. Samples from ward and theater staff and environment were also taken to look for possible mode of transmission. Data was recorded on a proforma. Discrete variables are expressed as percentages. Results: Staphylococcus aureus was the most frequent organism isolated in 34.6% cases. Methicillin sensitive Staphylococcus aureus was seen in 20% cases and methicillin resistant Staphylococcus aureus was seen in 14.6%. Out of these 14.6% MRSA, (17) 77% was associated with puerperal sepsis and rest (5) 23% was associated with postoperative wound infection. It showed best sensitivity to vancomycin. Conclusion: Staphylococcus aureus and E. coli were common causative agent of postoperative infections and puerperal sepsis. (author)

Prevalence and risk factors for Staphylococcus aureus and ...

African Journals Online (AJOL)

2015-09-05

Sep 5, 2015 ... Staphylococcus aureus (MSSA/MRSA) carriage among patients admitted to a chest clinic of a .... transport swab and sent to Erciyes University Halil Bayraktar .... admission among patients cared for at a 1000‑bedded public.

Prevalence of methicillin-resistant Staphylococcus aureus (MRSA ...

African Journals Online (AJOL)

One of each duplicate swab sample was inoculated directly onto chocolate agar, incubated for 24 hours at 37oc while the other swab was used to make a smear for Gram staining. All isolates were identified using standard microbiological methods. Staphylococcus aureus isolates were screened for methicillin resistance ...

Methicillin-resistant Staphylococcus aureus isolates from Iranian ...

African Journals Online (AJOL)

Methicillin-resistant Staphylococcus aureus isolates from Iranian restaurant food samples: Panton-Valentine Leukocidin, SCCmec phenotypes and antimicrobial resistance. ... TetK (80.72 %), linA (67.46 %), aadA1 (62.65 %), and msrA (55.42 %) were the most frequently identified resistance genes. SCCmec V (57.83%) ...

Lucky number seven: RNase 7 can prevent Staphylococcus aureus skin colonization.

Science.gov (United States)

Cho, John S; Xuan, Caiyun; Miller, Lloyd S

2010-12-01

Staphylococcus aureus colonization is a major risk factor for infection. In this issue, Simanski et al. demonstrate that the antimicrobial peptide RNase 7 is essential for preventing S. aureus colonization in human skin. These findings suggest that therapeutic interventions aimed at targeting RNase 7 production in the skin may be a novel strategy to protect against S. aureus infections.

Diversity of Staphylococcus aureus Isolates in European Wildlife.

Directory of Open Access Journals (Sweden)

Stefan Monecke

Full Text Available Staphylococcus aureus is a well-known colonizer and cause of infection among animals and it has been described from numerous domestic and wild animal species. The aim of the present study was to investigate the molecular epidemiology of S. aureus in a convenience sample of European wildlife and to review what previously has been observed in the subject field. 124 S. aureus isolates were collected from wildlife in Germany, Austria and Sweden; they were characterized by DNA microarray hybridization and, for isolates with novel hybridization patterns, by multilocus sequence typing (MLST. The isolates were assigned to 29 clonal complexes and singleton sequence types (CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88, CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425, CC2671, ST2691, CC2767 and ST2963, some of which (ST2425, ST2691, ST2963 were not described previously. Resistance rates in wildlife strains were rather low and mecA-MRSA isolates were rare (n = 6. mecC-MRSA (n = 8 were identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-associated lineages CC479 and CC705 were not detected in wildlife in the present study while, in contrast, a third common cattle lineage, CC97, was found to be common among cervids. No Staphylococcus argenteus or Staphylococcus schweitzeri-like isolates were found. Systematic studies are required to monitor the possible transmission of human- and livestock-associated S. aureus/MRSA to wildlife and vice versa as well as the possible transmission, by unprotected contact to animals. The prevalence of S. aureus/MRSA in wildlife as well as its population structures in different wildlife host species warrants further investigation.

Changes of Antimicrobial Resistance among Staphylococcus Aureus Isolated in 8 Consecutive Years in the First Bethune Hospital

Science.gov (United States)

Xu, Wei; Zhou, Qi; Yang, Chunguang; Yao, Hanxin; Xu, Jiancheng

This study was to investigate the antimicrobial resistance of Staphylococcus aureus isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 1469 strains of Staphylococcus aureus were collected from sputum 705 (18.0%), secretions 206 (14.0%), pus 177 (12.0%) during the past 8 years. The rates of methicillin-resistant Staphylococcus aureus (MRSA) were between 50.8% and 83.3% during the past 8 years, respectively. In recent 8 years, the antimicrobial resistance of Staphylococcus aureus had increased. Monitoring the antimicrobial resistance to Staphylococcus aureus should be strengthened. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from being transmitted.

Antimicrobial resistance of Staphylococcus aureus isolates from dairy cows and genetic diversity of resistant isolates

Science.gov (United States)

Staphylococcus aureus is a frequent and major contagious mastitis bacterial pathogen. The antibiotic treatment cure rates vary considerably from 4% to 92%. Staphylococcus aureus readily becomes resistant to antibiotics, resulting in persistent noncurable intramammary infection that usually results i...

Methicillin-resistant Staphylococcus aureus: Prevalence, incidence, risk factors, and effects on survival of patients in a specialist palliative care unit: A prospective observational study.

Science.gov (United States)

Gleeson, Aoife; Larkin, Philip; Walsh, Cathal; O'Sullivan, Niamh

2016-04-01

Little is known about the impact of methicillin-resistant Staphylococcus aureus in palliative care settings. To date, the clinical impact of methicillin-resistant Staphylococcus aureus in palliative care is unknown. To determine prevalence and incidence of methicillin-resistant Staphylococcus aureus colonisation in a specialist palliative care setting, to identify risk factors for methicillin-resistant Staphylococcus aureus colonisation, to determine the eradication success rate and to determine the impact of methicillin-resistant Staphylococcus aureus on survival. Prospective cohort study. Data were collected for consecutive admissions to an inpatient palliative care service. Patients were screened for methicillin-resistant Staphylococcus aureus colonisation on admission and 1 week post admission. Methicillin-resistant Staphylococcus aureus eradication was attempted in methicillin-resistant Staphylococcus aureus positive patients. Data were collected from 609 admissions for 466 individual patients. Admission screening data were available in 95.5%. Prevalence of methicillin-resistant Staphylococcus aureus colonisation was 11.59% (54 patients). One week incidence of methicillin-resistant Staphylococcus aureus colonisation was 1.2%. Risk factors for methicillin-resistant Staphylococcus aureus colonisation were determined using Chi-Squared test and included high Waterlow score (p resistant Staphylococcus aureus status prior to admission (p resistant Staphylococcus aureus was eradicated in 8.1% of admissions, while 46 patients commenced on the protocol (62.2%) died before completing it. Methicillin-resistant Staphylococcus aureus did not significantly impact survival but was significantly associated with having infection episodes and longer length of stay. This study identified risk factors for methicillin-resistant Staphylococcus aureus colonisation in palliative care patients. Methicillin-resistant Staphylococcus aureus was eradicated in 8.1% of patients. Hence

Petrifilm rapid S. aureus Count Plate method for rapid enumeration of Staphylococcus aureus in selected foods: collaborative study.

Science.gov (United States)

Silbernagel, K M; Lindberg, K G

2001-01-01

A rehydratable dry-film plating method for Staphylococcus aureus in foods, the 3M Petrifilm Rapid S. aureus Count Plate method, was compared with AOAC Official Method 975.55 (Staphylococcus aureus in Foods). Nine foods-instant nonfat dried milk, dry seasoned vegetable coating, frozen hash browns, frozen cooked chicken patty, frozen ground raw pork, shredded cheddar cheese, fresh green beans, pasta filled with beef and cheese, and egg custard-were analyzed for S. aureus by 13 collaborating laboratories. For each food tested, the collaborators received 8 blind test samples consisting of a control sample and 3 levels of inoculated test sample, each in duplicate. The mean log counts for the methods were comparable for pasta filled with beef and cheese; frozen hash browns; cooked chicken patty; egg custard; frozen ground raw pork; and instant nonfat dried milk. The repeatability and reproducibility variances of the Petrifilm Rapid S. aureus Count Plate method were similar to those of the standard method.

Zinc resistance within swine associated methicillin resistant Staphylococcus aureus (MRSA) isolates in the USA is associated with MLST lineage

Science.gov (United States)

Zinc resistance in livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA) is mediated by the czrC gene co-located with the mecA gene, encoding methicillin resistance, on the type V SCCmec element. Since the czrC gene and the mecA gene are co-located on the SCCmec element, it has ...

Effects of Fermented Sumach on the Formation of Slime Layer of Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Sahra Kırmusaoğlu

2012-03-01

Full Text Available Objective: Staphylococcus aureus (S. aureus is one of the most commonly isolated bacterial pathogens in hospitals, and the most frequent cause of nosocomial infections. Nosocomial staphylococcal foreign-body infections related to biofilm formation are a serious threat, demanding new therapeutic and preventive strategies. Implantation of intravenous catheters and surgical implantation of prosthetic implants carry a risk of infection. In order to prevent all these effects of biofilms, a study was designed to observe the possible antibacterial effect of sumach (Rhus coriaria on the biofilm formation of S. aureus. Material and Methods: The influence of varying concentrations of sumach on the formation of biofilms by 13 strains of Staphylococcus aureus was tested by a microelisa assay. Results: The significant differences between varying concentrations of sumach (0.1, 0.2, 0.5 and 1.0 µl/ml were observed in four methicillin resistant Staphylococcus aureus (MRSA and nine methicillin sensitive Staphylococcus aureus (MSSA (p<0.05. In bacteria, a dose-related decrease in the formation of slime, which is a major virulence factor of staphylococcal infections, was observed. Conclusion: In our study, using 0.1, 0.2, 0.5 and 1.0 µl/ml of sumach, thirteen strains lost, 17%, 22%, 28% and 48% respectively of their capacity to produce biofilms. Sumach, which is a herbal product, can decrease the formation of biofilm, which is a major virulence factor in staphylococcal infections.

Xanthgranulomatous pyelonephritis associated with staphylococcus aureus

International Nuclear Information System (INIS)

Al-Hwiesh, Abdulla K.

2007-01-01

A 44-year-old man with xanthgranulomatous pyelonephritis presented with abdominal distention, left lumber pain, fever, loss of appetite and loss of weight. He had been known to have diabetes mellitus type II for 20 years and he was diagnosed to have a left renal stone three months prior to this presentation. The patient's urine and the left psous abscess grew staphylococcus aureus. (author)

Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

NARCIS (Netherlands)

A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

2015-01-01

textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we

Elucidating the crucial role of poly N-acetylglucosamine from Staphylococcus aureus in cellular adhesion and pathogenesis.

Directory of Open Access Journals (Sweden)

Mei Hui Lin

Full Text Available Staphylococcus aureus is an important pathogen that forms biofilms on the surfaces of medical implants. Biofilm formation by S. aureus is associated with the production of poly N-acetylglucosamine (PNAG, also referred to as polysaccharide intercellular adhesin (PIA, which mediates bacterial adhesion, leading to the accumulation of bacteria on solid surfaces. This study shows that the ability of S. aureus SA113 to adhere to nasal epithelial cells is reduced after the deletion of the ica operon, which contains genes encoding PIA/PNAG synthesis. However, this ability is restored after a plasmid carrying the entire ica operon is transformed into the mutant strain, S. aureus SA113Δica, showing that the synthesis of PIA/PNAG is important for adhesion to epithelial cells. Additionally, S. carnosus TM300, which does not produce PIA/PNAG, forms a biofilm and adheres to epithelial cells after the bacteria are transformed with a PIA/PNAG-expressing plasmid, pTXicaADBC. The adhesion of S. carnosus TM300 to epithelial cells is also demonstrated by adding purified exopolysaccharide (EPS, which contains PIA/PNAG, to the bacteria. In addition, using a mouse model, we find that the abscess lesions and bacterial burden in lung tissues is higher in mice infected with S. aureus SA113 than in those infected with the mutant strain, S. aureus SA113Δica. The results indicate that PIA/PNAG promotes the adhesion of S. aureus to human nasal epithelial cells and lung infections in a mouse model. This study elucidates a mechanism that is important to the pathogenesis of S. aureus infections.

Efek Antibakteri dari Rebusan Daun Sambiloto (Andrographis paniculata Nees dan Produk Herbal Sambiloto Terhadap Staphylococcus Aureus

Directory of Open Access Journals (Sweden)

Adriyan Sikumalay

2016-01-01

Full Text Available AbstrakSambiloto (Andrographis paniculata Nees merupakan tanaman obat yang memiliki berbagai khasiat, salah satunya sebagai antibakteri.  Staphylococcus aureus merupakan penyebab utama infeksi. Penggunaan Sambiloto di masyarakat saat ini mempunyai beberapa pilihan diantaranya dengan membuat rebusan langsung dari daun sambiloto ataupun dengan membeli produk herbal sambiloto yang dijual di pasaran. Tujuan penelitian ini adalah menentukan efek antibakteri dari rebusan daun sambiloto (Andrographis paniculata Nees dan produk herbal sambiloto terhadap Staphylococcus aureus. Jenis penelitian adalah eksperimental dengan sembilan kali pengulangan menggunakan metode difusi. Penelitian dilakukan di laboratorium Mikrobiologi Fakultas Kedokteran Universitas Andalas Padang dari Maret  sampai Desember 2014. Sambiloto diekstrak dengan metode infusum. Kontrol yang digunakan adalah amoksisilin. Hasil penelitian memperlihatkan tidak ada daerah bebas kuman di sekitar cakram disk yang telah mengandung sambiloto. Kesimpulan hasil ini ialah rebusan daun sambiloto (Andrographis paniculata Nees dan produk herbal sambiloto tidak mempunyai efek antibakteri terhadap Staphylococcus aureus.Kata kunci: sambiloto, staphylococcus aureus, infusum AbstractBitter (Andrographis paniculata Nees is a medicinal plant that have various benefits, such as an antibacterial. Staphylococcus aureus is a major cause of infection. The use of bitter in today's society has several options such as by making direct decoction of the leaves of bitter or by buying herbal products of bitter sold in the market. The objective  of this study was to determine the antibacterial effect of decocted leaf of bitter (Andrographis paniculata Nees and herbal products of bitter against Staphylococcus aureus.This type of research was experimental with nine repetitions using diffusion method. This research was conducted in the laboratory of Microbiology Faculty of Medicine Andalas University Padang in March to

Staphylococcus aureus resistente a la meticilina (SARM)

Centers for Disease Control (CDC) Podcasts

2007-10-22

Datos importantes sobre las infecciones por SARM en Estados Unidos, en las escuelas y los entornos médicos. (Title: Methicillin-resistant Staphylococcus aureus (MRSA)Created: 10/2007).  Created: 10/22/2007 by National Center for Preparedness, Detection, and Control of Infectious Diseases.   Date Released: 11/9/2007.

Low Efficacy of Antibiotics Against Staphylococcus aureus Airway Colonization in Ventilated Patients.

Science.gov (United States)

Stulik, Lukas; Hudcova, Jana; Craven, Donald E; Nagy, Gabor; Nagy, Eszter

2017-04-15

Airway-colonization by Staphylococcus aureus predisposes to the development of ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP). Despite extensive antibiotic treatment of intensive care unit patients, limited data are available on the efficacy of antibiotics on bacterial airway colonization and/or prevention of infections. Therefore, microbiologic responses to antibiotic treatment were evaluated in ventilated patients. Results of semiquantitative analyses of S. aureus burden in serial endotracheal-aspirate (ETA) samples and VAT/VAP diagnosis were correlated to antibiotic treatment. Minimum inhibitory concentrations of relevant antibiotics using serially collected isolates were evaluated. Forty-eight mechanically ventilated patients who were S. aureus positive by ETA samples and treated with relevant antibiotics for at least 2 consecutive days were included in the study. Vancomycin failed to reduce methicillin-resistant S. aureus (MRSA) or methicillin-susceptible S. aureus (MSSA) burden in the airways. Oxacillin was ineffective for MSSA colonization in approximately 30% of the patients, and responders were typically coadministered additional antibiotics. Despite antibiotic exposure, 15 of the 39 patients (approximately 38%) colonized only by S. aureus and treated with appropriate antibiotic for at least 2 days still progressed to VAP. Importantly, no change in antibiotic susceptibility of S. aureus isolates was observed during treatment. Staphylococcus aureus colonization levels inversely correlated with the presence of normal respiratory flora. Antibiotic treatment is ineffective in reducing S. aureus colonization in the lower airways and preventing VAT or VAP. Staphylococcus aureus is in competition for colonization with the normal respiratory flora. To improve patient outcomes, alternatives to antibiotics are urgently needed. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of

Development of the immune response in pneumonia due to Staphylococcus aureus (part 2

Directory of Open Access Journals (Sweden)

A.E. Abaturov

2017-04-01

Full Text Available The article analyzes the role of pattern-recognition receptors involved in recognition of pathogen-associated molecular patterns of Staphylococcus aureus. There are shown the basic operation of macrophage and monocyte NLRP3, NLRC5, NLRP7, AIM2 inflammasomes that form the active forms of pro-inflammatory cytokines IL-1-beta and IL-18 du-ring the development of pneumonia caused by Staphylococcus aureus.

Polymerase chain reaction assay for detection of Staphylococcus aureus in buffalo milk

Directory of Open Access Journals (Sweden)

V.K. Jain

2010-02-01

Full Text Available In India, Haryana has the world’s best dairy type buffalo, the Murrah capable of milk yields as high as 35 kg a day. Clinical and Sub clinical mastitis exerts a negative impact on milk quality, quantity and animal health and profits. In India, Staphylococci are the main causative agents responsible for mastitis of economic importance. Therefore, a suitable and specific test is required for the rapid diagnosis of Staphylococcus aureus. For definitive diagnosis of Staphylococcus aureus in mastitic milk, a polymerase chain reaction assay was developed using target sequence of 16S to 23S rRNA spacer region. This test can be performed within hours and avoids cumbersome and lengthy steps involved in microbiological culture of milk and biochemical tests. Polymerase chain reaction assay can be used as a screening test for a large herd to detect Staphylococcus aureus in milk.

Genetic Determinants of High-Level Oxacillin Resistance in Methicillin-Resistant Staphylococcus aureus.

Science.gov (United States)

Pardos de la Gandara, Maria; Borges, Vitor; Chung, Marilyn; Milheiriço, Catarina; Gomes, João Paulo; de Lencastre, Herminia; Tomasz, Alexander

2018-06-01

Methicillin-resistant Staphylococcus aureus (MRSA) strains carry either a mecA - or a mecC -mediated mechanism of resistance to beta-lactam antibiotics, and the phenotypic expression of resistance shows extensive strain-to-strain variation. In recent communications, we identified the genetic determinants associated with the stringent stress response that play a major role in the antibiotic resistant phenotype of the historically earliest "archaic" clone of MRSA and in the mecC -carrying MRSA strain LGA251. Here, we sought to test whether or not the same genetic determinants also contribute to the resistant phenotype of highly and homogeneously resistant (H*R) derivatives of a major contemporary MRSA clone, USA300. We found that the resistance phenotype was linked to six genes ( fruB , gmk , hpt , purB , prsA , and relA ), which were most frequently targeted among the analyzed 20 H*R strains (one mutation per clone in 19 of the 20 H*R strains). Besides the strong parallels with our previous findings (five of the six genes matched), all but one of the repeatedly targeted genes were found to be linked to guanine metabolism, pointing to the key role that this pathway plays in defining the level of antibiotic resistance independent of the clonal type of MRSA. Copyright © 2018 American Society for Microbiology.

Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus

OpenAIRE

Jing Zhang; Yujuan Suo; Daofeng Zhang; Fangning Jin; Hang Zhao; Chunlei Shi

2018-01-01

Staphyloxanthin (STX), a golden carotenoid pigment produced by Staphylococcus aureus, is suggested to act as an important virulence factor due to its antioxidant properties. Restraining biosynthesis of STX was considered as an indicator of virulence decline in pigmented S. aureus isolates. However, it is not clear whether natural non-pigmented S. aureus isolates have less virulence than pigmented ones. In this study, it is aimed to compare the pigmented and non-pigmented S. aureus isolates to...

Genetic Diversity of Staphylococcus aureus in Buruli Ulcer

NARCIS (Netherlands)

Amissah, Nana Ama; Glasner, Corinna; Ablordey, Anthony; Tetteh, Caitlin S.; Kotey, Nana Konama; Prah, Isaac; van der Werf, Tjip; Rossen, John W.; van Dijl, Jan Maarten; Stienstra, Ymkje

Background Buruli ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present

Nigribactin, a Novel Siderophore from Vibrio nigripulchritudo, Modulates Staphylococcus aureus Virulence Gene Expression

DEFF Research Database (Denmark)

Nielsen, Anita; Månsson, Maria; Wietz, Matthias

2012-01-01

Staphylococcus aureus is a serious human pathogen that employs a number of virulence factors as part of its pathogenesis. The purpose of the present study was to explore marine bacteria as a source of compounds that modulate virulence gene expression in S. aureus. During the global marine Galathea...... 3 expedition, a strain collection was established comprising bacteria that express antimicrobial activity against Vibrio anguillarum and/or Staphylococcus aureus. Within this collection we searched colony material, culture supernatants, and cell extracts for virulence modulating activity showing......, enterobactin, failed to influence S. aureus virulence gene expression. This study shows that marine microorganisms produce compounds with potential use in therapeutic strategies targeting virulence rather than viability of human pathogens....

Response of Methicillin-Resistant Staphylococcus aureus to Amicoumacin A

OpenAIRE

Lama, Amrita; Pané-Farré, Jan; Chon, Tai; Wiersma, Anna M.; Sit, Clarissa S.; Vederas, John C.; Hecker, Michael; Nakano, Michiko M.

2012-01-01

Amicoumacin A exhibits strong antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA), hence we sought to uncover its mechanism of action. Genome-wide transcriptome analysis of S. aureus COL in response to amicoumacin A showed alteration in transcription of genes specifying several cellular processes including cell envelope turnover, cross-membrane transport, virulence, metabolism, and general stress response. The most highly induced gene was lrgA, encoding an antiho...

METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS IN LAB COATS OF NURSING STUDENTS

Directory of Open Access Journals (Sweden)

Jean Phellipe Marques do Nascimento

2016-05-01

Full Text Available The aim of the present study was to investigate the presence of Staphylococcus sp. in lab coats nursing students, in addition to determining the antimicrobial sensitivity profile of the isolated bacteria. The bacterial samples were collected, identified and characterized phenotypically, with subsequent determination of antimicrobial sensitivity profile by disk diffusion technique, according to recommendation of the Clinical and Laboratory Standards Institute. 57 colonies were isolated, where 51% were identified as Staphylococcus coagulase negative, 47% as Staphylococcus aureus and 2% belonging to a genus not identified. Among the samples identified as S. aureus, 15% were resistant to Oxacillin and 55% showed resistance to more than one antimicrobial.The results obtained in this work strengthen the role of the lab coat as a source of contamination of pathogenic microorganisms, as well as its possible role in the spread of these pathogens within and outside the hospital environment

Fresh garlic extract inhibits Staphylococcus aureus biofilm formation under chemopreventive and chemotherapeutic conditions

Directory of Open Access Journals (Sweden)

Panan Ratthawongjirakul

2016-08-01

Full Text Available Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA are the leading aetiological pathogens of nosocomial infections worldwide. These bacteria form biofilms on both biotic and abiotic surfaces causing biofilm-associated infections. Within the biofilm, these bacteria might develop persistent and antimicrobial resistant characteristics resulting in chronic infections and treatment failures. Garlic exhibits broad pharmaceutical properties and inhibitory activities against S. aureus. We investigated the effects of aqueous fresh garlic extract on biofilm formation in S. aureus ATCC25923 and MRSA strains under chemopreventive and chemotherapeutic conditions. The viable bacteria and biofilm levels were quantified through colony count and crystal violet staining, respectively. The use of fresh garlic extract under both conditions significantly inhibited biofilm formation in S. aureus strains ATCC25923 and MRSA. Garlic could be developed as either a prophylactic or therapeutic agent to manage S. aureus biofilm-associated infections.

Emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different animal species

NARCIS (Netherlands)

Cuny, Christiane; Friedrich, Alexander; Kozytska, Svetlana; Layer, Franziska; Nübel, Ulrich; Ohlsen, Knut; Strommenger, Birgit; Walther, Birgit; Wieler, Lothar; Witte, Wolfgang

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in animals such as horses, pet animals and productive livestock has raised questions of a probable human origin and in more general of host specificity of S. aureus. Particular clonal lineages are obviously specific for humans (e.g.

Antibacterial activity of mupirocin (pseudomonic Acid A) against, clinical isolates of methicillin-resistant staphylococcus aureus

International Nuclear Information System (INIS)

Farooq, M.; Abbasi, S.A.; Butt, T.; Arain, M.A

2010-01-01

Colonized patients and health care workers are the main source of spread of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The elimination of nasal colonized MRSA plays a crucial role in infection control protocols. Mupirocin (pseudomonic acid A) is used for eradication of MRSA nasal carriage. Increasing use of pseudomonic acid A (mupirocin) has led to emergence of resistance. Objective To determine low and high level resistance of MRSA isolates from clinical specimens against mupirocin. Place and duration of study: Study was conducted at Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi from July 2006 to June 2007. Material and methods Three hundred methicillin-resistant Staphylococcus aureus isolates were studied. All clinical specimens were processed for culture and sensitivity. Staphylococcus aureus isolates were tested for methicillin resistance using 1 micro g oxacillin disk. The isolates were further tested by PCR for the presence of mecA gene. Minimum Inhibitory Concentration (MIC) of mupirocin against MRSA isolates was determined using agar dilution technique. Results Out of 300 MRSA isolates, 98% were found to have MlC against mupirocin as smaller than 4 micro g/mL. Remaining 2% isolates revealed low level resistance (MIC greater than 8 micro g/mL to 256 micro g/mL), no high level resistance (MIC greater than 512 micro g/mL) against mupirocin was detected. Conclusions: High level mupirocin resistance has not emerged so far in our setup. Due to increasing use of mupirocin, emergence of resistance against mupirocin among MRSA is a strong possibility. Strategy encompassing rational use of antimicrobials, hospital infection control, surveillance for the detection of mupirocin resistance and judicious use of this agent is required. (author)

Staphylococcus aureus phage types and their correlation to antibiotic resistance

Directory of Open Access Journals (Sweden)

Mehndiratta P

2010-10-01

Full Text Available Context: Staphylococcus aureus is one of the most devastating human pathogen. The organism has a differential ability to spread and cause outbreak of infections. Characterization of these strains is important to control the spread of infection in the hospitals as well as in the community. Aim: To identify the currently existing phage groups of Staphylococcus aureus, their prevalence and resistance to antibiotics. Materials and Methods: Study was undertaken on 252 Staphylococcus aureus strains isolated from clinical samples. Strains were phage typed and their resistance to antibiotics was determined following standard microbiological procedures. Statistical Analysis: Chi square test was used to compare the antibiotic susceptibility between methicillin resistant Staph. aureus (MRSA and methicillin sensitive S. aureus (MSSA strains. Results: Prevalence of MRSA and MSSA strains was found to be 29.36% and 70.65% respectively. Of these 17.56% of MRSA and 40.44% of MSSA strains were community acquired. All the MSSA strains belonging to phage type 81 from the community were sensitive to all the antibiotics tested including clindamycin and were resistant to penicillin. Forty five percent strains of phage group III and 39% of non-typable MRSA strains from the hospital were resistant to multiple antibiotics. Conclusion: The study revealed that predominant phage group amongst MRSA strains was phage group III and amongst MSSA from the community was phage group NA (phage type 81. MSSA strains isolated from the community differed significantly from hospital strains in their phage type and antibiotic susceptibility. A good correlation was observed between community acquired strains of phage type 81 and sensitivity to gentamycin and clindamycin.

Pyrazole Based Inhibitors against Enzymes of Staphylococcus aureus

DEFF Research Database (Denmark)

Jagadeesan, G.; Vijayakuma, Vinodhkumar; Palayam, Malathy

2015-01-01

agents. The current study focuses on molecular docking and dynamics studies of pyrazole derivatives against Nucleosidase and DNA gyrase B of Staphylococcus aureus. Molecular docking and dynamics studies reveal that some of these derivatives show better binding abilities than some of the current drugs...

Global analysis of the impact of linezolid onto virulence factor production in S. aureus USA300.

Science.gov (United States)

Bonn, Florian; Pané-Farré, Jan; Schlüter, Rabea; Schaffer, Marc; Fuchs, Stephan; Bernhardt, Jörg; Riedel, Katharina; Otto, Andreas; Völker, Uwe; van Dijl, Jan Maarten; Hecker, Michael; Mäder, Ulrike; Becher, Dörte

2016-05-01

The translation inhibitor linezolid is an antibiotic of last resort against Gram-positive pathogens including methicillin resistant strains of the nosocomial pathogen Staphylococcus aureus. Linezolid is reported to inhibit production of extracellular virulence factors, but the molecular cause is unknown. To elucidate the physiological response of S. aureus to linezolid in general and the inhibition of virulence factor synthesis in particular a holistic study was performed. Linezolid was added to exponentially growing S. aureus cells and the linezolid stress response was analyzed with transcriptomics and quantitative proteomics methods. In addition, scanning and transmission electron microscopy experiments as well as fluorescence microscopy analyses of the cellular DNA and membrane were performed. As previously observed in studies on other translation inhibitors, S. aureus adapts its protein biosynthesis machinery to the reduced translation efficiency. For example the synthesis of ribosomal proteins was induced. Also unexpected results like a decline in the amount of extracellular and membrane proteins were obtained. In addition, cell shape and size changed after linezolid stress and cell division was diminished. Finally, the chromosome was condensed after linezolid stress and lost contact to the membrane. These morphological changes cannot be explained by established theories. A new hypothesis is discussed, which suggests that the reduced amount of membrane and extracellular proteins and observed defects in cell division are due to the disintegration of transertion complexes by linezolid. Copyright © 2016 Elsevier GmbH. All rights reserved.

Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

Directory of Open Access Journals (Sweden)

Luciane Cristina Gelatti

2009-08-01

Full Text Available Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticilina adquirido na comunidade no Sul do Brasil. O paciente foi atendido em Unidade de Emergência com história de ferimento provocado por trauma em membro inferior que evoluiu para celulite, pneumonia e sepse.Methicillin-resistant Staphylococcus aureus was initially described as a typical microorganism acquired in nosocomial infections. However, over recent years, community-acquired methicillin-resistant Staphylococcus aureus has been a cause of skin and soft-tissue infections. Serious infections such as pneumonia and sepsis can also occur. This report describes a case of sepsis in a child that was complicated by pneumonia secondary to soft tissue lesions that were due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil. The patient was attended at the Emergency Unit with a history of injury caused by lower-limb trauma that evolved to cellulitis, pneumonia and sepsis.

PRODUKSI IGY SPESIFIK STAPHYLOCOCCUS AUREUS DARI ISOLAT ASAL KASUS STAPHYLOCOCCOSIS PADA KELINCI

Directory of Open Access Journals (Sweden)

Triwardhani Cahyaningsih

2017-04-01

Full Text Available This experiment aims to produce immunoglobulin Y (Ig-Y Staphylococcus aureus isolates origin staphylococcosis case in rabbits. Vaccination is done several times using Staphylococcus aureus active in 109 cfu/ml. Injecting the chicken is done four weeks in a row, the first week is done by intravenous injection of S. aureus antigens, the second week of the injection sub cutan S. aureus emulsified with Freund's complete adjuvant, followed by the third and fourth week of the injection of S. aureus antigen emulsified with incomplete Freund's adjuvant. Egg samples were taken after four weeks of the last injection for identification, purification, and determination of specific IgY against S. aureus in egg yolk. IgY specificity qualitatively tests performed by the AGP test (To Gel Precipitation. IgY extraction is done using PEG - Ammonium sulfate, purified IgY concentration calculated by the method of Bradford. The results showed that IgY began to be detected in egg yolk at week six after immunization, with the average levels of IgY is 1.7 mg/ml.

Spontaneous methicillin-resistant Staphylococcus aureus (MRSA) meningitis.

Science.gov (United States)

Longhurst, William D; Sheele, Johnathan M

2018-05-01

Spontaneous methicillin-resistant Staphylococcus aureus (MRSA) meningitis is extremely rare and has a high mortality rate. We report a case of MRSA meningitis in an otherwise healthy young adult female with no recent trauma or neurosurgical interventions. Despite antibiotics she suffered a vasculitis-induced cerebral vascular ischemic event. Copyright © 2018 Elsevier Inc. All rights reserved.

Prevalence of Methicillin-Resistant Staphylococcus aureus from Equine Nasopharyngeal and Guttural Pouch Wash Samples.

Science.gov (United States)

Boyle, A G; Rankin, S C; Duffee, L A; Morris, D

2017-09-01

Methicillin-resistant Staphylococcus aureus (MRSA) is recognized as a cause of nosocomial infections in both human and veterinary medicine. Studies that examine the nasopharynx and guttural pouches of the horse as carriage sites for MRSA have not been reported. MRSA colonizes the nasopharynx and guttural pouch of horses. To determine the prevalence of MRSA in equine nasopharyngeal wash (NPW) and guttural pouch lavage (GPL) samples in a field population of horses. One hundred seventy-eight samples (123 NPW and 55 GPL) from 108 horses. Prospective study. Samples were collected from a convenience population of clinically ill horses with suspected Streptococcus equi subsp. equi (S. equi) infection, horses convalescing from a known S. equi infection, and asymptomatic horses undergoing S. equi screening. Samples were submitted for S. aureus aerobic bacterial culture with mannitol salt broth and two selective agars (cefoxitin CHROMagar as the PBP2a inducer and mannitol salt agar with oxacillin). Biochemical identification of Staphylococcus species and pulsed-field gel electrophoresis (PFGE), to determine clonal relationships between isolates, were performed. Methicillin-resistant Staphylococcus (MRS) was isolated from the nasopharynx of 7/108 (4%) horses. Three horses had MRSA (2.7%), and 4 had MR-Staphylococcus pseudintermedius (MRSP). MRSA was isolated from horses on the same farm. PFGE revealed the 3 MRSA as USA 500 strains. Sampling the nasopharynx and guttural pouch of community-based horses revealed a similarly low prevalence rate of MRSA as other studies sampling the nares of community-based horses. More study is required to determine the need for sampling multiple anatomic sites when screening horses for MRSA. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Growth-Environment Dependent Modulation of Staphylococcus aureus Branched-Chain to Straight-Chain Fatty Acid Ratio and Incorporation of Unsaturated Fatty Acids.

Science.gov (United States)

Sen, Suranjana; Sirobhushanam, Sirisha; Johnson, Seth R; Song, Yang; Tefft, Ryan; Gatto, Craig; Wilkinson, Brian J

2016-01-01

The fatty acid composition of membrane glycerolipids is a major determinant of Staphylococcus aureus membrane biophysical properties that impacts key factors in cell physiology including susceptibility to membrane active antimicrobials, pathogenesis, and response to environmental stress. The fatty acids of S. aureus are considered to be a mixture of branched-chain fatty acids (BCFAs), which increase membrane fluidity, and straight-chain fatty acids (SCFAs) that decrease it. The balance of BCFAs and SCFAs in USA300 strain JE2 and strain SH1000 was affected considerably by differences in the conventional laboratory medium in which the strains were grown with media such as Mueller-Hinton broth and Luria broth resulting in high BCFAs and low SCFAs, whereas growth in Tryptic Soy Broth and Brain-Heart Infusion broth led to reduction in BCFAs and an increase in SCFAs. Straight-chain unsaturated fatty acids (SCUFAs) were not detected. However, when S. aureus was grown ex vivo in serum, the fatty acid composition was radically different with SCUFAs, which increase membrane fluidity, making up a substantial proportion of the total (37%) and BCFAs (>36%) making up the rest. Staphyloxanthin, an additional major membrane lipid component unique to S. aureus, tended to be greater in content in cells with high BCFAs or SCUFAs. Cells with high staphyloxanthin content had a lower membrane fluidity that was attributed to increased production of staphyloxanthin. S. aureus saves energy and carbon by utilizing host fatty acids for part of its total fatty acids when growing in serum, which may impact biophysical properties and pathogenesis given the role of SCUFAs in virulence. The nutritional environment in which S. aureus is grown in vitro or in vivo in an infection is likely to be a major determinant of membrane fatty acid composition.

In vitro Antibacterial Activity of Mentha Essential Oils Against Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Horváth P.

2017-09-01

Full Text Available Plant extracts and essential oils (EOs are characterized by their antibacterial properties against various bacterial pathogens, including staphylococci. Some strains of these bacteria are resistant against the adverse effects of the environment including antibiotics, e. g. methicillin-resistant Staphylococcus aureus (MRSA. EOs alone cannot substitute for antibiotics but their treatment may be useful to intensify and strengthen the effects of antibiotics on pathogenic staphylococci. In this work, we tested the antibacterial effects of the essential oils of Mentha species with menthol as one of the effective substances against different strains of S. aureus. Two in vitro methods were used, the qualitative disc diffusion assay and the quantitative minimal inhibitory concentration (MIC of selected essential oils. Peppermint oil from Mentha piperita, spearmint oil from Mentha spicata var. crispa and cornmint oil from Mentha arvensis were tested in this study against the various strains of Staphylococcus aureus, including methicillin resistant Staphylococcus aureus (MRSA. The oils were dissolved in DMSO (dimethyl sulfoxide and diluted at the following ratios: 1 : 1, 1 : 2, 1 : 5, and 1 : 10. Based on the results determined by the agar disc diffusion test, the highest antibacterial properties were observed in spearmint oil against S. aureus CCM 4223 at 1 : 2 ratio where the inhibition zone varied at a range of 35.67 ± 6.81 mm. We determined also the MIC of all the oils where concentrations of the oils were as follows: 1 %; 0.5 %; 0.25 %; 0.125 % and 0.0625 %. The lowest concentrations of essential oils that possessed inhibitory effects on the growth of S. aureus varied between 0.125 % and 0.25 %.

Are Nasal Carriers of Staphylococcus aureus More Likely To Become Colonized or Infected with Methicillin-Resistant Staphylococcus aureus on Admission to a Hospital?▿

OpenAIRE

Krebes, Juliane; Al-Ghusein, Hasan; Feasey, Nick; Breathnach, Aodhan; Lindsay, Jodi A.

2010-01-01

Of 840 patients at hospital admission, 2.7% were positive for methicillin-resistant Staphylococcus aureus (MRSA) and 22.3% were positive for methicillin-susceptible S. aureus (MSSA). During the next 8 months, 4.8% of the MSSA-positive patients acquired MRSA with no lineage association. A total of 5.2% of noncarriers acquired MRSA. We find no evidence that colonized hosts are more susceptible to acquiring MRSA.

Presentación atípica de piomiositis tropical difusa de psoas por Staphylococcus aureus meticilino resistente Atypical presentation of diffuse tropical pyomiositis of the psoas due to methicillin resistant Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Ray Ticse

2012-03-01

Full Text Available La piomiositis tropical difusa primaria es una enfermedad de presentación infrecuente en nuestro medio, con pocos casos asociados a Staphylococcus aureus meticilino resistente, adquirido en la comunidad (MRSA-AC. Se presenta el caso de un paciente de 70 años, con tratamiento irregular para diabetes mellitus tipo 2, que fue hospitalizado por presentar un cuadro de diez días de evolución, con dolor lumbar irradiado a miembro inferior izquierdo, fiebre y flexión forzada de la cadera derecha por dolor a la movilización. El diagnóstico de piomiositis difusa de ambos psoas se realizó con resonancia magnética. Del cultivo de una colección paravertebral posterior se aisló Staphylococcus aureus resistente a oxacilina, penicilina y dicloxacilina.Diffuse tropical primary pyomyositis is an infrequent entity in our country, with few cases associated to communityacquired Methicillin- resistant Staphylococcus aureus. There are no reported cases of Community-Acquired Methicillin- Resistant Staphylococcus aureus (CA- MRSA in Peru. We present the case of a 70 year old male with a previous diagnosis of type 2 diabetes mellitus, receiving irregular treatment, who was admitted to the hospital with a history of 10 days of low back pain radiating to the left leg, fever and forced flexion of the right hip due to pain during movement. The diagnosis of diffuse pyomyositis of both psoas muscles was performed with MRI and culture of a posterior paravertebral collection, from which Staphylococcus aureus resistant to oxacillin, penicillin and dicloxacillin was isolated.

Occurrence of Staphylococcus aureus in cattle, sheep, goat, and pig rearing in the Czech Republic

Directory of Open Access Journals (Sweden)

Marcela Klimešová

2017-01-01

Full Text Available The study focused on the prevalence of Staphylococcus aureus and resistant strains in livestock. In this study, 114 different samples from three cattle farms (84 from two farms of dairy cows and 30 from one farm of suckler cows, 132 samples from one sheep farm, 120 samples from one goat farm, and 82 samples from three pig farms were examined. Strains identified as Staphylococcus aureus were further analysed by the polymerase chain reaction method for detection of the mecA gene and for confirmation of the sequence type 398. Positive incidence of Staphylococcus aureus was confirmed in farms of suckler cows, sheep, goats and pigs. The incidence of methicilin-resistant Staphylococcus aureus was confirmed at a goat farm, with all strains belonging to the sequence type 398. Repetitive element palindromic-polymerase chain reaction analysis was performed to compare the relatedness of selected human and animal S. aureus strains at the goat and sheep farms. The obtained data from repetitive element-polymerase chain reaction analysis showed significant clonal similarity among the tested isolates and indicated the possibility of mutual transmission between animals or animal and human and possible transfer in the food chain.

Occurrence of Methicilin-resistant Staphylococcus aureus in a ...

African Journals Online (AJOL)

VO Ogunleye, AO Ogunleye, ATP Ajuwape, KA Akande, AI Adetosoye ... Taking into consideration the danger associated with methicillin resistant Staphylococcus aureus, the findings from this study underscores the need for public enlightenment of both the hospital workers and the general public on the risk associated with ...

Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer

NARCIS (Netherlands)

Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Sabat, Artur J.; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten; Rossen, John W.; Stienstra, Ymkje

Background Buruli ulcer (BU) is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus. Methodology This study investigated possible patient-to-patient transmission events of S. aureus during

Methicillin-resistant Staphylococcus aureus transmission

DEFF Research Database (Denmark)

Andersen, Leif Percival; Nielsen, Xiaohui

2015-01-01

INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...... increase the risk of contaminating hands, arms and the front of the uniform. Hand hygiene is therefore essential, but the use of protection gowns with long sleeves is also important in order to prevent transmission of MRSA. After culture of MRSA and implementation of specific precautions to prevent...

Subinhibitory quinupristin/dalfopristin attenuates virulence of Staphylococcus aureus.

Science.gov (United States)

Koszczol, Carmen; Bernardo, Katussevani; Krönke, Martin; Krut, Oleg

2006-09-01

The semi-synthetic streptogramin quinupristin/dalfopristin antibiotic exerts potent bactericidal activity against Staphylococcus aureus. We investigated whether, like other bactericidal antibiotics used at subinhibitory concentrations, quinupristin/dalfopristin enhances release of toxins by Gram-positive cocci. The activity of quinupristin/dalfopristin on exotoxin release by S. aureus was investigated by 2D SDS-PAGE combined with MALDI-TOF/MS analysis and by western blotting. We show that quinupristin/dalfopristin at subinhibitory concentrations reduces the release of S. aureus factors that induce tumour necrosis factor secretion in macrophages. Furthermore, quinupristin/dalfopristin but not linezolid attenuated S. aureus-mediated killing of infected host cells. When added to S. aureus cultures at different stages of bacterial growth, quinupristin/dalfopristin reduced in a dose-dependent manner the release of specific virulence factors (e.g. autolysin, protein A, alpha- and beta-haemolysins, lipases). In contrast, other presumably non-toxic exoproteins remained unchanged. The results of the present study suggest that subinhibitory quinupristin/dalfopristin inhibits virulence factor release by S. aureus, which might be especially helpful for the treatment of S. aureus infections, where both bactericidal as well as anti-toxin activity may be advantageous.

Staphylococcus aureus Colonization of the Mouse Gastrointestinal Tract Is Modulated by Wall Teichoic Acid, Capsule, and Surface Proteins.

Directory of Open Access Journals (Sweden)

Yoshiki Misawa

2015-07-01

Full Text Available Staphylococcus aureus colonizes the nose, throat, skin, and gastrointestinal (GI tract of humans. GI carriage of S. aureus is difficult to eradicate and has been shown to facilitate the transmission of the bacterium among individuals. Although staphylococcal colonization of the GI tract is asymptomatic, it increases the likelihood of infection, particularly skin and soft tissue infections caused by USA300 isolates. We established a mouse model of persistent S. aureus GI colonization and characterized the impact of selected surface antigens on colonization. In competition experiments, an acapsular mutant colonized better than the parental strain Newman, whereas mutants defective in sortase A and clumping factor A showed impaired ability to colonize the GI tract. Mutants lacking protein A, clumping factor B, poly-N-acetyl glucosamine, or SdrCDE showed no defect in colonization. An S. aureus wall teichoic acid (WTA mutant (ΔtagO failed to colonize the mouse nose or GI tract, and the tagO and clfA mutants showed reduced adherence in vitro to intestinal epithelial cells. The tagO mutant was recovered in lower numbers than the wild type strain in the murine stomach and duodenum 1 h after inoculation. This reduced fitness correlated with the in vitro susceptibility of the tagO mutant to bile salts, proteases, and a gut-associated defensin. Newman ΔtagO showed enhanced susceptibility to autolysis, and an autolysin (atl tagO double mutant abrogated this phenotype. However, the atl tagO mutant did not survive better in the mouse GI tract than the tagO mutant. Our results indicate that the failure of the tagO mutant to colonize the GI tract correlates with its poor adherence and susceptibility to bactericidal factors within the mouse gut, but not to enhanced activity of its major autolysin.

Study on biofilm-forming properties of clinical isolates of Staphylococcus aureus.

Science.gov (United States)

Taj, Yasmeen; Essa, Farhan; Aziz, Faisal; Kazmi, Shahana Urooj

2012-05-14

The purpose of this study was to observe the formation of biofilm, an important virulence factor, by isolates of Staphylococcus aureus (S. aureus) in Pakistan by different conventional methods and through electron microscopy. We screened 115 strains of S. aureus isolated from different clinical specimens by tube method (TM), air-liquid interface coverslip assay method, Congo red agar (CRA) method, and scanning electron microscopy (SEM). Out of 115 S. aureus isolates, 63 (54.78%) showed biofilm formation by tube method. Biofilm forming bacteria were further categorized as high producers (n = 23, 20%) and moderate producers (n = 40, 34.78%). TM coordinated well with the coverslip assay for strong biofilm-producing strains in 19 (16.5%) isolates. By coverslip method, weak producers were difficult to differentiate from biofilm negative isolates. Screening on CRA showed biofilm formation only in four (3.47%) strains. Scanning electron micrographs showed the biofilm-forming strains of S. aureus arranged in a matrix on the propylene surface and correlated well with the TM. Biofilm production is a marker of virulence for clinically relevant staphylococcal infections. It can be studied by various methods but screening on CRA is not recommended for investigation of biofilm formation in Staphylococcus aureus. Electron micrograph images correlate well with the biofilm production as observed by TM.

Dehydrosqualene Desaturase as a Novel Target for Anti-Virulence Therapy against Staphylococcus aureus

OpenAIRE

Gao, Peng; Davies, Julian; Kao, Richard Yi Tsun

2017-01-01

ABSTRACT Staphylococcus aureus, especially methicillin-resistant S.?aureus (MRSA), is a life-threatening pathogen in hospital- and community-acquired infections. The golden-colored carotenoid pigment of S.?aureus, staphyloxanthin, contributes to the resistance to reactive oxygen species (ROS) and host neutrophil-based killing. Here, we describe a novel inhibitor (NP16) of S.?aureus pigment production that reduces the survival of S.?aureus under oxidative stress conditions. Carotenoid componen...

Antibiotic sensitivity pattern of Staphylococcus aureus from clinical ...

African Journals Online (AJOL)

Background: The importance of Staphylococcus aureus as a persistent nosocomial and community acquired pathogen has become a global health concern. It has a remarkable capability of evolving different mechanisms of resistance to most antimicrobial agents. The aim of the present study is to establish the incidence of ...

Methicilin-resistant Staphylococcus aureus (MRSA) at Jos University ...

African Journals Online (AJOL)

A prospective surveillance of Methicillin resistant staphylococcus aureus (MRSA) was carried out at Jos University Teaching Hospital, Nigeria, over a one year period. This study highlights the continuos importance of MRSA in causing both hospital and to a less extent community acquired infections. Out of the 180 ...

Psoriasis and staphylococcus aureus skin colonization in Moroccan ...

African Journals Online (AJOL)

Psoriatic lesions are rarely complicated by recurrent infections. The aim of our study is to determine skin colonisation and nasal carriage of Staphylococcus aureus in patients with psoriasis and in healthy persons. Patients and methods: a comparative study that include 33 patients with psoriasis and 33 healthy persons.

Methicillin-resistant Staphylococcus aureus containing mecC in Swedish dairy cows

Directory of Open Access Journals (Sweden)

Unnerstad Helle Ericsson

2013-01-01

Full Text Available Abstract Background Hitherto, methicillin-resistant Staphylococcus aureus (MRSA has not been detected in Swedish cattle. However, due to the report of mecC, a novel homologue to the mecA gene, there was reason to re-evaluate susceptibility results from strain collections of Staphylococcus aureus and test suspected isolates for the presence of mecC. Findings Bovine isolates of S. aureus with elevated minimum inhibitory concentrations of beta-lactams were retrospectively tested for presence of mecC. In four of the isolates mecC was detected. Conclusion In Sweden, this is the first finding of MRSA in cattle and the first detection of MRSA harbouring mecC of domestic animal origin. MRSA in animal populations has implications as a potential reservoir with risk for spread to humans. Occurrence of MRSA among Swedish cattle appears still very limited.

Methicillin-resistant Staphylococcus aureus in Pig Farming

OpenAIRE

Voss, Andreas; Loeffen, Frans; Bakker, Judith; Klaassen, Corne; Wulf, Mireille

2005-01-01

We conducted a study among a group of 26 regional pig farmers to determine the methicillin-resistant Staphylococcus aureus prevalence rate and found it was >760 times greater than the rate of patients admitted to Dutch hospitals. While spa-type t108 is apparently a more widespread clone among pig farmers and their environment, we did find other spa-types.

Host- and tissue-specific pathogenic traits of Staphylococcus aureus.

NARCIS (Netherlands)

W.B. van Leeuwen (Willem); D.C. Melles (Damian); A. Alaidan (Alwaleed); M. Al-Ahdal (Mohammed); H.A.M. Boelens (Hélène); S.V. Snijders (Susan); H.F.L. Wertheim (Heiman); E. van Duijkeren (Engeline); J.K. Peeters (Justine); P.J. van der Spek (Peter); R.F.J. Gorkink (Raymond); G. Simons (Guus); H.A. Verbrugh (Henri); A.F. van Belkum (Alex)

2005-01-01

textabstractComparative genomics were used to assess genetic differences between Staphylococcus aureus strains derived from infected animals versus colonized or infected humans. A total of 77 veterinary isolates were genetically characterized by high-throughput amplified fragment length polymorphism

Assessing the potential for raw meat to influence human colonization with Staphylococcus aureus

OpenAIRE

Carrel, Margaret; Zhao, Chang; Thapaliya, Dipendra; Bitterman, Patrick; Kates, Ashley E.; Hanson, Blake M.; Smith, Tara C.

2017-01-01

The role of household meat handling and consumption in the transfer of Staphylococcus aureus (S. aureus) from livestock to consumers is not well understood. Examining the similarity of S. aureus colonizing humans and S. aureus in meat from the stores in which those individuals shop can provide insight into the role of meat in human S. aureus colonization. S. aureus isolates were collected from individuals in rural and urban communities in Iowa (n?=?3347) and contemporaneously from meat produc...

The Effect of Robusta Coffe Extract (Coffea Robusta) as Inhibitors of Growth Staphylococcus Aureus

OpenAIRE

Mumun Nurmilawati, Muhammad Ainul Yaqin

2015-01-01

Chlorogenic and caffeine acid, which is a non-volatile organic acids in coffee, which can prevent the growth of some gram-positive and gram-negative bacteria including Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Pseudomonas fluorescens, Staphylococcus aureus, Bacillus cereus, Lactobacillus bulgaricus, Streptococcus lactis and Streptococcus faecalis.Subject used in this study was Staphylococcus aureus were divided into 5 groups, where each group consisting of 8 repetitions. The...

A Closer Look at the Transcriptome of Staphylococcus aureus

NARCIS (Netherlands)

Smits, N.J.P.

2012-01-01

Tight regulation of genes upon changing environments is important in establishing and maintaining infections by pathogens. In Staphylococcus aureus, gene expression and particularly controlled expression of various groups of genes dependent on growth and environmental conditions is essential for

Differentiation between Staphylococcus aureus and Staphylococcus epidermidis strains using Raman spectroscopy

Czech Academy of Sciences Publication Activity Database

Rebrošová, K.; Šiler, Martin; Samek, Ota; Růžička, F.; Bernatová, Silvie; Ježek, Jan; Zemánek, Pavel; Holá, V.

2017-01-01

Roč. 12, č. 10 (2017), s. 881-890 ISSN 1746-0913 R&D Projects: GA ČR(CZ) GA15-20645S; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Raman spectroscopy * rapid diagnostics * Staphylococcus epidermidis * Staphyococcus aureus Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 3.374, year: 2016

A study of Staphylococcus aureus nasal carriage, antibacterial ...

African Journals Online (AJOL)

Aim: This study was to determine the virulence encoding genes, and the antibiotic resistance patterns of the Staphylococcus aureus isolates, which were isolated from the nasal samples of chest clinic patients. Materials and Methods: The nasal samples of the in‑patients (431) and out‑patients (1857) in Kayseri Training and ...

Enterotoxicity of Staphylococcus aureus isolated from beans pudding

African Journals Online (AJOL)

36 samples of beans pudding from selected sources were analysed for Staphylococcus aureus and Bacillus cereus using standard protocols aimed at assessing its bacteriological quality. Samples obtained from restaurant showed slightly lower value for total plate count (1.3 x 104 - 1.6 x 106 cfu/gm) compared to samples ...

spa typing for epidemiological surveillance of Staphylococcus aureus

NARCIS (Netherlands)

Hallin, Marie; Friedrich, Alexander W; Struelens, Marc J; Caugant, Dominique A.

2009-01-01

The spa typing method is based on sequencing of the polymorphic X region of the protein A gene (spa), present in all strains of Staphylococcus aureus. The X region is constituted of a variable number of 24-bp repeats flanked by well-conserved regions. This single-locus sequence-based typing method

PARAMETER KINETIKA INAKTIVASI TERMAL DAN ISOLASI Staphylococcus aureus PADA MINUMAN DARI GEL CINCAU HIJAU DAN ROSELA [Thermal Inactivation Kinetics Parameter and Isolation of Staphylococcus aureus on Drink from Green Grass Jelly and Roselle

Directory of Open Access Journals (Sweden)

Eko Hari Purnomo

2015-07-01

Full Text Available Information about heat resistance (D and z values of target bacteria is needed for the thermal process design on drink from Green Grass Jelly (Premna oblongifolia Merr. and Roselle (Hibiscus sabdariffa L., so it can guarantee quality and safety of the product. The objectives of this research were to isolate Staphylococcus aureus from commercial green grass jelly and to determine the D and z values of Staphylococcus aureus (from commercial product and standard clinical isolate ATCC 25923 on heating menstruum of green grass jelly and roselle. Isolation of S. aureus was done by inoculation in selective medium, D and z values of Staphylococcus aureus were assessed by heating at constant temperatures of 57, 53, 49, and 45°C during the time interval 2.5, 5, 10, and 15 minutes. The results showed that one isolate (Isolate A gave positive response of Staphylococcus aureus in isolation tests and had similar percentage with the reference culture of 41.8% using the API Staph Kit. Heat resistance of Staphylococcus aureus (represented as D value isolated from green grass jelly at constant heating temperature of D45, D49, D53 and D57 were 32.3, 17.9, 4.6, and 1.5 minutes. On the other hand, D value of isolates ATCC 25923 (standard clinical isolate at constant heating temperature of D45, D49, D53 and D57 were 18.5, 6.8, 2.9, and 1.4 minutes. The z value of isolates A and ATCC 25923 were 8.8°C and 10.8°C. Smaller z value of isolate A showed that pasteurization process can be accelerated and optimized with increasing the temperature slightly but has the same lethality effect.

Influence of antibiotic pressure on bacterial bioluminescence, with emphasis on Staphylococcus aureus

NARCIS (Netherlands)

Daghighi, Seyedmojtaba; Sjollema, Jelmer; Harapanahalli, Akshay; Dijkstra, Rene J. B.; van der Mei, Henny C.; Busscher, Henk J.

2015-01-01

Bioluminescence imaging is used for longitudinal evaluation of bacteria in live animals. Clear relations exist between bacterial numbers and their bioluminescence. However, bioluminescence images of Staphylococcus aureus Xen29, S. aureus Xen36 and Escherichia coli Xen14 grown on tryptone soy agar in

Combined Staining Techniques for Demonstration of Staphylococcus aureus Biofilm in Routine Histopathology

DEFF Research Database (Denmark)

Jensen, Louise Kruse; Henriksen, Nicole Lind; Bjarnsholt, Thomas

2018-01-01

Aim: Visualization of Staphylococcus aureus biofilm using histochemical staining and combined histochemistry (HC) and immunohistochemistry (IHC). Methods: The ability of S. aureus S54F9 to form biofilm was tested in vitro. Hereafter, infected bone tissue was collected from two different porcine m...

Altered gene expression of Staphylococcus aureus upon interaction with human endothelial cells

NARCIS (Netherlands)

Vriesema, A.J.M.; Beekhuizen, H.; Hamdi, M.; Soufan, A.; Lammers, A.; Willekens, B.; Bakker, O.; Veltrop, M.H.A.M.; Gevel, van de J.S.; Dankert, J.; Zaat, S.A.J.

2000-01-01

Staphylococcus aureus is isolated from a substantial number of patients with infective endocarditis who are not known to have predisposing heart abnormalities. It has been suggested that the infection is initiated by the direct binding of S. aureus to human vascular endothelium. To determine the

Altered gene expression in Staphylococcus aureus upon interaction with human endothelial cells

NARCIS (Netherlands)

Vriesema, A. J.; Beekhuizen, H.; Hamdi, M.; Soufan, A.; Lammers, A.; Willekens, B.; Bakker, O.; Welten, A. G.; Veltrop, M. H.; van de Gevel, J. S.; Dankert, J.; Zaat, S. A.

2000-01-01

Staphylococcus aureus is isolated from a substantial number of patients with infective endocarditis who are not known to have predisposing heart abnormalities. It has been suggested that the infection is initiated by the direct binding of S. aureus to human vascular endothelium. To determine the

Staphylococcus aureus resistente a vancomicina.

Directory of Open Access Journals (Sweden)

Carlos Andrés Rodríguez

2005-12-01

Full Text Available Objetivo. Revisar la evolución y mecanismos moleculares de la resistencia de Staphylococcus aureus a vancomicina. Fuente de los datos. Se consultó la base de datos MEDLINE y se seleccionaron artículos tipo reportes de caso, estudios bioquímicos, de microscopía electrónica y biología molecular pertinentes. Síntesis. Después de casi 40 años de eficacia ininterrumpida de la vancomicina, en 1997 se reportaron los primeros casos de fracaso terapéutico debido a cepas de Staphylococcus aureus con resistencia intermedia, denominadas VISA (concentración inhibitoria mínima, CIM, 8 a 16 ?g/ml, así como a cepas con resistencia heterogénea hVISA (CIM global = 4 ?g/ml, pero con subpoblaciones VISA, en las cuales la resistencia está mediada por engrosamiento de la pared celular y disminución de su entrecruzamiento, lo que afecta la llegada del antibiótico al blanco principal, los monómeros del peptidoglicano en la membrana plasmática. En 2002 se aisló la primera de las 3 cepas reportadas hasta la fecha con resistencia total al antibiótico, denominadas VRSA (CIM>32 ?g/ml, en las que se encontró el transposón Tn1546 proveniente de Enterococcus spp, responsable del reemplazo de la terminación D-Ala-D-Ala por D-Ala-Dlactato en los precursores de la pared celular con pérdida de la afinidad por el glicopéptido. Conclusiones. La resistencia a vancomicina es una realidad en S. aureus, mediada en el caso de VISA por alteraciones en la pared celular que atrapan el antibiótico antes de llegar al sitio de acción, y en el caso de VRSA, por transferencia desde Enterococcus spp. de genes que llevan a la modificación del blanco molecular.

Pulsed-field gel electrophoresis typing of Staphylococcus aureus isolates

Science.gov (United States)

Pulsed-field gel electrophoresis (PFGE) is the most applied and effective genetic typing method for epidemiological studies and investigation of foodborne outbreaks caused by different pathogens, including Staphylococcus aureus. The technique relies on analysis of large DNA fragments generated by th...

Low efficacy of tobramycin in experimental Staphylococcus aureus endocarditis

DEFF Research Database (Denmark)

Lerche, C. J.; Christophersen, L. J.; Trøstrup, H.

2015-01-01

The empiric treatment of infective endocarditis (IE) varies widely and, in some places, a regimen of penicillin in combination with an aminoglycoside is administered. The increasing incidence of Staphylococcus aureus IE, poor tissue penetration by aminoglycosides and low frequency of penicillin...

Rapid differentiation of Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative staphylococci and meticillin susceptibility testing directly from growth-positive blood cultures by multiplex real-time PCR.

Science.gov (United States)

Jukes, Leanne; Mikhail, Jane; Bome-Mannathoko, Naledi; Hadfield, Stephen J; Harris, Llinos G; El-Bouri, Khalid; Davies, Angharad P; Mack, Dietrich

2010-12-01

This study evaluated a multiplex real-time PCR method specific for the mecA, femA-SA and femA-SE genes for rapid identification of Staphylococcus aureus, Staphylococcus epidermidis and non-S. epidermidis coagulase-negative staphylococci (CoNS), and meticillin susceptibility testing directly in positive blood cultures that grew Gram-positive cocci in clusters. A total of 100 positive blood cultures produced: 39 S. aureus [12 meticillin-resistant S. aureus (MRSA), 31% of all the S. aureus]; 30 S. epidermidis (56.6% of the CoNS), 8 Staphylococcus capitis (15.1%), 3 Staphylococcus saprophyticus (5.7%), 4 Staphylococcus hominis (7.5%), 3 Staphylococcus haemolyticus (5.7%), 2 Staphylococcus warneri (3.8%), 1 Staphylococcus cohnii (1.9%) and 2 unidentified Staphylococcus spp. (3.8%); and 1 Micrococcus luteus in pure culture. Two blood cultures had no growth on subculture and five blood cultures grew mixed CoNS. For the 95 blood cultures with pure growth or no growth on subculture, there was very good agreement between real-time PCR and the BD Phoenix identification system for staphylococcal species categorization in S. aureus, S. epidermidis and non-S. epidermidis CoNS and meticillin-resistance determination (Cohen's unweighted kappa coefficient κ=0.882). All MRSA and meticillin-susceptible S. aureus were correctly identified by mecA amplification. PCR amplification of mecA was more sensitive for direct detection of meticillin-resistant CoNS in positive blood cultures than testing with the BD Phoenix system. There were no major errors when identifying staphylococcal isolates and their meticillin susceptibility within 2.5 h. Further studies are needed to evaluate the clinical benefit of using such a rapid test on the consumption of glycopeptide antibiotics and the alteration of empiric therapy in the situation of positive blood cultures growing staphylococci, and the respective clinical outcomes.

The Plasmin-Sensitive Protein Pls in Methicillin-Resistant Staphylococcus aureus (MRSA Is a Glycoprotein.

Directory of Open Access Journals (Sweden)

Isabelle Bleiziffer

2017-01-01

Full Text Available Most bacterial glycoproteins identified to date are virulence factors of pathogenic bacteria, i.e. adhesins and invasins. However, the impact of protein glycosylation on the major human pathogen Staphylococcus aureus remains incompletely understood. To study protein glycosylation in staphylococci, we analyzed lysostaphin lysates of methicillin-resistant Staphylococcus aureus (MRSA strains by SDS-PAGE and subsequent periodic acid-Schiff's staining. We detected four (>300, ∼250, ∼165, and ∼120 kDa and two (>300 and ∼175 kDa glycosylated surface proteins with strain COL and strain 1061, respectively. The ∼250, ∼165, and ∼175 kDa proteins were identified as plasmin-sensitive protein (Pls by mass spectrometry. Previously, Pls has been demonstrated to be a virulence factor in a mouse septic arthritis model. The pls gene is encoded by the staphylococcal cassette chromosome (SCCmec type I in MRSA that also encodes the methicillin resistance-conferring mecA and further genes. In a search for glycosyltransferases, we identified two open reading frames encoded downstream of pls on the SCCmec element, which we termed gtfC and gtfD. Expression and deletion analysis revealed that both gtfC and gtfD mediate glycosylation of Pls. Additionally, the recently reported glycosyltransferases SdgA and SdgB are involved in Pls glycosylation. Glycosylation occurs at serine residues in the Pls SD-repeat region and modifying carbohydrates are N-acetylhexosaminyl residues. Functional characterization revealed that Pls can confer increased biofilm formation, which seems to involve two distinct mechanisms. The first mechanism depends on glycosylation of the SD-repeat region by GtfC/GtfD and probably also involves eDNA, while the second seems to be independent of glycosylation as well as eDNA and may involve the centrally located G5 domains. Other previously known Pls properties are not related to the sugar modifications. In conclusion, Pls is a glycoprotein and

Predictors of Staphylococcus aureus Colonization and Results after Decolonization

Directory of Open Access Journals (Sweden)

Tennison L. Malcolm

2016-01-01

Full Text Available Protocols for the screening and decolonization of Staphylococcus aureus prior to total joint arthroplasty (TJA have become widely adopted. The goals of this study were to determine: (1 whether implementation of a screening protocol followed by decolonization with mupirocin/vancomycin and chlorhexidine reduces the risk of revision compared with no screening protocol (i.e., chlorhexidine alone and (2 whether clinical criteria could reliably predict colonization with MSSA and/or MRSA. Electronic medical records of primary patients undergoing TJA that were screened (n=3,927 and were not screened (n=1,751 for Staphylococcus aureus at least 4 days prior to surgery, respectively, were retrospectively reviewed. All patients received chlorhexidine body wipes preoperatively. Patients carrying MSSA and MRSA were treated preoperatively with mupirocin and vancomycin, respectively, along with the standard preoperative antibiotics and chlorhexidine body wipes. Screened patients were 50% less likely to require revision due to prosthetic joint infection compared to those not screened (p=0.04. Multivariate regression models were poorly accurate in predicting colonization with MSSA (AUC = 0.58 and MRSA (AUC = 0.62. These results support the routine screening and decolonization of S. aureus prior to TJA.

The role of the Staphylococcal VraTSR regulatory system on vancomycin resistance and vanA operon expression in vancomycin-resistant Staphylococcus aureus.

Science.gov (United States)

Qureshi, Nadia K; Yin, Shaohui; Boyle-Vavra, Susan

2014-01-01

Vancomycin is often the preferred treatment for invasive methicillin-resistant Staphylococcus aureus (MRSA) infection. With the increase in incidence of MRSA infections, the use of vancomycin has increased and, as feared, isolates of vancomycin-resistant Staphylococcus aureus (VRSA) have emerged. VRSA isolates have acquired the entercoccal vanA operon contained on transposon (Tn) 1546 residing on a conjugal plasmid. VraTSR is a vancomycin and β-lactam-inducible three-component regulatory system encoded on the S. aureus chromosome that modulates the cell-wall stress response to cell-wall acting antibiotics. Mutation in vraTSR has shown to increase susceptibility to β-lactams and vancomycin in clinical VISA strains and in recombinant strain COLVA-200 which expresses a plasmid borne vanA operon. To date, the role of VraTSR in vanA operon expression in VRSA has not been demonstrated. In this study, the vraTSR operon was deleted from the first clinical VRSA strain (VRS1) by transduction with phage harvested from a USA300 vraTSR operon deletion strain. The absence of the vraTSR operon and presence of the vanA operon were confirmed in the transductant (VRS1Δvra) by PCR. Broth MIC determinations, demonstrated that the vancomycin MIC of VRS1Δvra (64 µg/ml) decreased by 16-fold compared with VRS1 (1024 µg/ml). The effect of the vraTSR operon deletion on expression of the van gene cluster (vanA, vanX and vanR) was examined by quantitative RT-PCR using relative quantification. A 2-5-fold decreased expression of the vanA operon genes occured in strain VRS1Δvra at stationary growth phase compared with the parent strain, VRS1. Both vancomycin resistance and vancomycin-induced expression of vanA and vanR were restored by complementation with a plasmid harboring the vraTSR operon. These findings demonstrate that expression in S. aureus of the horizontally acquired enterococcal vanA gene cluster is enhanced by the staphylococcal three-component cell wall stress regulatory

Sensitivity test of staphylococcus aureus against extract tinospora crispa

OpenAIRE

Lucia Ratna Winata Muslimin

2017-01-01

A bacterium such as Staphylococcus aureus ( S.aureus) produces a kind of toxic protein which can disrupt intestinal wall. Livestock reacts to these toxins by pumping lots of water into the intestine in order to rinse or flush these toxins. As a result, the livestock have diarrhea as a body response to remove the toxin in the digestive system. In the presence of these problems, farmers take a measure such as using antibiotics freely. Among farmers, antibiotics are often used freely without kn...

Analisis Cemaran Staphylococcus aureus pada Gelas, Darah Segar, dan Jamu dengan Ramuan Darah Ular Kobra Jawa (Naja sputatrix

Directory of Open Access Journals (Sweden)

Roza Azizah Primatika

2017-01-01

rerata cemaran Staphylococcus aureus menunjukkan tidak ada perbedaan antara swab gelas, darah dan ramuan darah ular kobra. Walaupun demikian, jamu yang mengandung darah ular kobra berpotensi mengandung Staphylococcus aureus yang membahayakan konsumen.

The adhesive and immunomodulating properties of the multifunctional Staphylococcus aureus protein Eap

NARCIS (Netherlands)

Harraghy, Niamh; Hussain, Muzaffar; Haggar, Axana; Chavakis, Triantafyllos; Sinha, Bhanu; Herrmann, Mathias; Flock, Jan-Ingmar

2003-01-01

Adherence of Staphylococcus aureus to the host tissue is an important step in the initiation of pathogenesis. At least 10 adhesins produced by S. aureus have been described and it is becoming clear that the expression of these adhesins and their interactions with eukaryotic cells involve complex

Detection of some virulence factors in Staphylococcus aureus ...

African Journals Online (AJOL)

Detection of some virulence factors in Staphylococcus aureus isolated from clinical and subclinical bovine mastitis in Iran. ... Mastitis is one of the common diseases of dairy cattle and an inflammatory response of the mammary glands tissue. ... and B genes, 10 samples contained agrI gene, 42 samples contained agrII gene, ...

Identification and characterization of methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus pettenkoferi from a small animal clinic.

Science.gov (United States)

Weiss, Sonja; Kadlec, Kristina; Fessler, Andrea T; Schwarz, Stefan

2013-12-27

The aim of this study was to isolate and characterize methicillin-resistant staphylococci (MRS) in a small animal clinic and to investigate their distribution and possible transmission. Swabs (n=72) were taken from hospitalized pets, the environment and employees of a small animal clinic and screened for the presence of MRS. The staphylococcal species was confirmed biochemically or by 16S rDNA sequencing. Susceptibility to antimicrobial agents was tested by broth dilution. The presence of mecA and other resistance genes was confirmed by PCR. Molecular typing of the isolates followed standard procedures. In total, 34 MRS belonging to the four species Staphylococcus aureus (n=5), Staphylococcus epidermidis (n=21), Staphylococcus haemolyticus (n=6) or Staphylococcus pettenkoferi (n=2) were isolated. All isolates were multidrug-resistant with resistance to at least three classes of antimicrobial agents. Among the five methicillin-resistant S. aureus (MRSA) isolates, four belonged to the clonal complex CC398; two of them were isolated from cats, the remaining two from pet cages. Overall, the MRS isolates differed in their characteristics, except for one S. epidermidis clone (n=9) isolated from hospitalized cats without clinical staphylococcal infections, pet cages, the clinic environment as well as from a healthy employee. This MRSE clone was resistant to 10 classes of antimicrobial agents, including aminocyclitols, β-lactams, fluoroquinolones, lincosamides, macrolides, phenicols, pleuromutilins, sulfonamides, tetracyclines and trimethoprim. These findings suggest a possible transmission of specific MRS isolates between animal patients, employees and the clinic environment. Copyright © 2013 Elsevier B.V. All rights reserved.

Factors associated with worse lung function in cystic fibrosis patients with persistent staphylococcus aureus

NARCIS (Netherlands)

Junge, S. (Sibylle); Görlich, D. (Dennis); Reijer, M.D. (Martijn Den); B. Wiedemann (Baerbel); B. Tümmler (Burkhard); H. Ellemunter; Dübbers, A. (Angelika); Küster, P. (Peter); M. Ballmann; Koerner-Rettberg, C. (Cordula); Große-Onnebrink, J. (Jörg); Heuer, E. (Eberhardt); Sextro, W. (Wolfgang); Mainz, J.G. (Jochen G.); Hammermann, J. (Jutta); Riethmüller, J. (Joachim); Graepler-Mainka, U.M. (Ute M.); Staab, D. (Doris); Wollschläger, B. (Bettina); Szczepanski, R. (Rüdiger); A. Schuster (Antje); Tegtmeyer, F.-K. (Friedrich-Karl); Sutharsan, S. (Sivagurunathan); Wald, A. (Alexandra); Nofer, J.-R. (Jerzy-Roch); W.J.B. van Wamel (Willem); Becker, K. (Karsten); Peters, G. (Georg); Kahl, B.C. (Barbara C.)

2016-01-01

textabstractBackground Staphylococcus aureus is an important pathogen in cystic fibrosis (CF). However, it is not clear which factors are associated with worse lung function in patients with persistent S. aureus airway cultures. Our main hypothesis was that patients with high S. aureus density in

Staphylococcus aureus Nasal Colonization Differs among Pig Lineages and Is Associated with the Presence of Other Staphylococcal Species.

Science.gov (United States)

Verstappen, Koen M; Willems, Eveline; Fluit, Ad C; Duim, Birgitta; Martens, Marc; Wagenaar, Jaap A

2017-01-01

Staphylococcus aureus is a common colonizer in pigs, with methicillin-resistant S. aureus (MRSA) in particular being a potential health risk to humans. To reduce the exposure to humans, the colonization in pigs should be reduced. The aim of this study was to quantitatively compare the susceptibility of pig lineages for S. aureus colonization, and if the absence of S. aureus could be associated with the presence or absence of other staphylococcal species. Nasal samples ( n  = 129) were obtained from seven different pig lineages in the Netherlands, France, and Germany. S. aureus and other staphylococci were enumerated from these samples by real-time (RT)-PCR and culture. Associations were explored between the presence of S. aureus and other staphylococci. S. aureus was detected by RT-PCR on all farms and in samples from pigs of all lineages. Twenty-five percent of the pigs from lineage F (from two farms) were colonized with S. aureus , while in all other lineages it was more than 50% ( p  Staphylococcus sciuri, Staphylococcus cohnii , and Staphylococcus saprophyticus were usually not found in combination with S. aureus in these samples. (i) pigs from different genetic lineages have different susceptibilities for colonization with S. aureus . These pigs might contain a genetic factor influencing nasal colonization. (ii) Colonization of S. aureus is also associated with the absence of S. sciuri, S. cohnii , or S. saprophyticus . (iii) The farm environment seems to influence the presence of S. aureus in pigs.

Global initiative for meticillin-resistant Staphylococcus aureus pneumonia (GLIMP)

DEFF Research Database (Denmark)

Aliberti, Stefano; Reyes, Luis F; Faverio, Paola

2016-01-01

BACKGROUND: Antibiotic resistance is a major global health problem and pathogens such as meticillin-resistant Staphylococcus aureus (MRSA) have become of particular concern in the management of lower respiratory tract infections. However, few data are available on the worldwide prevalence and ris...

Novel structurally designed vaccine for S. aureus α-hemolysin: protection against bacteremia and pneumonia.

Directory of Open Access Journals (Sweden)

Rajan P Adhikari

Full Text Available Staphylococcus aureus (S. aureus is a human pathogen associated with skin and soft tissue infections (SSTI and life threatening sepsis and pneumonia. Efforts to develop effective vaccines against S. aureus have been largely unsuccessful, in part due to the variety of virulence factors produced by this organism. S. aureus alpha-hemolysin (Hla is a pore-forming toxin expressed by most S. aureus strains and reported to play a key role in the pathogenesis of SSTI and pneumonia. Here we report a novel recombinant subunit vaccine candidate for Hla, rationally designed based on the heptameric crystal structure. This vaccine candidate, denoted AT-62aa, was tested in pneumonia and bacteremia infection models using S. aureus strain Newman and the pandemic strain USA300 (LAC. Significant protection from lethal bacteremia/sepsis and pneumonia was observed upon vaccination with AT-62aa along with a Glucopyranosyl Lipid Adjuvant-Stable Emulsion (GLA-SE that is currently in clinical trials. Passive transfer of rabbit immunoglobulin against AT-62aa (AT62-IgG protected mice against intraperitoneal and intranasal challenge with USA300 and produced significant reduction in bacterial burden in blood, spleen, kidney, and lungs. Our Hla-based vaccine is the first to be reported to reduce bacterial dissemination and to provide protection in a sepsis model of S. aureus infection. AT62-IgG and sera from vaccinated mice effectively neutralized the toxin in vitro and AT62-IgG inhibited the formation of Hla heptamers, suggesting antibody-mediated neutralization as the primary mechanism of action. This remarkable efficacy makes this Hla-based vaccine a prime candidate for inclusion in future multivalent S. aureus vaccine. Furthermore, identification of protective epitopes within AT-62aa could lead to novel immunotherapy for S. aureus infection.

Portación y caracterización de Staphylococcus aureus en manipuladores de alimentos Carriage and characterization of Staphylococcus aureus in food handlers

Directory of Open Access Journals (Sweden)

Graciela B Jordá

2012-06-01

Full Text Available Staphylococcus aureus es una causa de intoxicaciones alimentarias por su capacidad de producir enterotoxinas. Los manipuladores de alimentos que portan S. aureus productores de enterotoxinas pueden provocar intoxicaciones alimentarias. Se estudiaron muestras tomadas de fosas nasales de 88 manipuladores de alimentos en la provincia de Misiones. El 37,5 % de los individuos analizados eran portadores de S. aureus. Mediante técnicas de amplificación (PCR, se detectaron genes que codifican la producción de enterotoxinas en 13 de los 33 aislamientos obtenidos (39,4 % y en el 14,7 % de los manipuladores. De estos aislamientos, 10 portaban el gen sea y 3 el gen sec. El estudio de sensibilidad a los antibióticos mostró un 100 % de sensibilidad a teicoplanina, gentamiclna y rifampicina; 2 aislamientos fueron resistentes a clindamicina y a eritromicina y 4 resultaron resistentes a la meticilina. Estos resultados son un alerta e indicarían la necesidad de desarrollar medidas racionales para reducir el riesgo potencial de intoxicaciones alimentarias.Staphylococcus aureus causes food poisoning due to its ability to produce enterotoxins. Food handlers carrying enterotoxin-producing S. aureus can contaminate food, thus leading to food poisoning. Samples were obtained from 88 food handlers in the Province of Misiones, Argentina. S. aureus was isolated from nasal swaps and PCR amplification was performed for genes encoding staphylococcal enterotoxins. A total of 37.5 % food handlers were positive for S. aureus. Expression of enterotoxin genes was found in 13 of the 33 (39.4 % S. aureus isolates studied, accounting for 14.7 % of food handlers. Gene sea was detected in 10 isolates followed by gene sec in 3 isolates. All isolates were susceptible to teicoplanin, gentamicin and rifampicin. Four isolates were resistant to methicillin whereas 2 isolates were resistant to clindamycin and erythromycin. These results constitute a critical alert and indicate the need

Vancomycin-resistant Staphylococcus aureus (VRSA) in hepatic cirrhosis patient: a case report

Science.gov (United States)

Ramazoni, M.; Siregar, M. L.; Jamil, K. F.

2018-03-01

The irrational use of vancomycin in methicillin-resistant Staphylococcus aureus (MRSA) infections result in the emergence of vancomycin-resistant Staphylococcus aureus (VRSA) pathogen, which can pose a threat to the world healthcare. A 32-year-old male with hepatic cirrhosis patient admitted with recurrent gastrointestinal bleeding with a wound in his left leg since 6 months ago; the result microbiological culture showed a VRSA with minimum inhibitory concentration (MIC) vancomycin ≥32μg/mL The patient was treated with trimethoprim/sulfamethoxazole combination according to cultural sensitivity. The second microbiological culture showed thesame result. VRSA is a rare and difficult condition to handle. The success of therapy for this VRSA case warn us how important to cut the S. aureus distribution chain with a high level of resistance.

Mupirocin prophylaxis against nosocomial Staphylococcus aureus infections in nonsurgical patients: a randomized study

NARCIS (Netherlands)

M.C. Vos (Margreet); A. Ott (Alewijn); A. Voss (Andreas); J.A.J.W. Kluytmans (Jan); C.M.J.E. Vandenbroucke-Grauls (Christina); M.H.M. Meester (Marlene); P.H.J. van Keulen (Peter); H.A. Verbrugh (Henri); H.F.L. Wertheim (Heiman)

2004-01-01

textabstractBACKGROUND: Staphylococcus aureus nasal carriage is a major risk factor for nosocomial S. aureus infection. Studies show that intranasal mupirocin can prevent nosocomial surgical site infections. No data are available on the efficacy of mupirocin in nonsurgical

[Prevalence and predisposing factors of methicillin-resistant Staphylococcus aureus in long-term care facilities. An international view].

Science.gov (United States)

Szabó, Rita

2016-07-03

Methicillin-resistant Staphylococcus aureus is one of the most important pathogens of healthcare and long-term care-associated infections over the world, resulting high morbidity, mortality and extra costs in these settings. The authors analyze the prevalence and predisposing factors of methicillin-resistant Staphylococcus aureus in long-term care facilities. Systematic review using PubMed, ScienceDirect and Cochrane Library CENTRAL databases between January 1, 2006 and December 31, 2015 was performed. In the past ten years methicillin-resistant Staphylococcus aureus prevalence in European long-term care facilities (12.6%) was lower than in North America (33.9%). The most frequent predisposing factor was previous antimicrobial therapy, hospital admission and infection/colonisation, chronic wounds, and high care need. Based on the results, the prevention and control of methicillin-resistant Staphylococcus aureus is an important public health priority in the European and Hungarian long-term care facilities.

Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant S aureus, in nine European countries: a cross-sectional study.

NARCIS (Netherlands)

Heijer, C.D.J. den; Bijnen, E.M.E. van; Paget, W.J.; Pringle, M.; Goossen, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

2013-01-01

Background: Information about the prevalence of Staphylococcus aureus resistance to antimicrobial drugs has mainly been obtained from invasive strains, although the commensal microbiota is thought to be an important reservoir of resistance. We aimed to compare the prevalence of nasal S aureus

Frequency of the Occurence of Methicilin Resistant Staphylococcus aureus (MRSA Infections in Hyderabad, Pakistan

Directory of Open Access Journals (Sweden)

Nazir Ahmed Brohi

2017-06-01

Full Text Available Staphylococcus aureus is a potential pathogen of hospital and community related infections. It secretes toxins or the enzymes as virulence factor of mild to severe infections and show resistance to beta-lactam antibiotic including penicillin, methicillin, oxacillin and now vancomycin that could alarm of equal risk factors of Methicillin Resistant Staphylococcus aureus (MRSA infections in the patients. The survey report of 381 patients of Hyderabad, Pakistan was collected from March 2013 to June 2014 in which 176 cases were reported for Staphylococcus aureus in both genders of different age groups of 3-15 y kids, 16-45 y adults and 45-70 y olds, which showed 208 and 132 specimens Staphylococcus infection and 16 and 4 cases of MRSA infections in male and female patients, respectively whereas other 31 cases showed no infection. The laboratory diagnosis of the 200 samples from various hospitalized patients revealed the highest percentage of Methicillin Resistant Staphylococcus aureus MRSA in pus and post-operative wounds (17% followed by skin swabs (10%, sputum (7% and blood (0%. The observations revealed greater prevalence of MRSA infection in elderly age 16-45 years males than the females and other age groups. Antibiotic susceptibility test of 26 antibiotics revealed resistance (R-53%, sensitive (S-39 and variable (V-7% sensitivity zones (mm. Amplification of mecA gene was done using PCR reaction that revealed mecA gene bands up to 150-200 base pairs by test resistant strains.

Genome-wide association study reveals a locus for nasal carriage of Staphylococcus aureus in Danish crossbred pigs

DEFF Research Database (Denmark)

Skallerup, Per; Gongora, Carmen Espinosa; Jørgensen, Claus Bøttcher

2015-01-01

BACKGROUND: Staphylococcus aureus is an important human opportunistic pathogen residing on skin and mucosae of healthy people. Pigs have been identified as a source of human colonization and infection with methicillin-resistant Staphylococcus aureus (MRSA) and novel measures are needed to control......-pathogen interaction seems to be independent of S. aureus genotype. CONCLUSION: Our results suggest it may be possible to select pigs genetically resistant to S. aureus nasal colonization as a tool to control transmission of livestock-associated MRSA to humans....

Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

Directory of Open Access Journals (Sweden)

Maria Elena Velázquez-Meza

2005-10-01

Full Text Available Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epidemiológicas ha provisto nuevas herramientas para conocer el origen y las vías de diseminación de este microorganismo. Una de las conclusiones importantes que han surgido de este tipo de estudios es que un número pequeño de clonas son las responsables de las infecciones estafilocócicas en todo el mundo.Nosocomial infections due to methicillin-resistant Staphylococcus aureus (MRSA is an important health problem worldwide. This microorganism causes a variety of clinical infections, including osteomyelitis, invasive endocarditis, septic arthritis and septicemia. Antimicrobial resistance is a factor that influences the persistence of MRSA in the hospital environment. The introduction of molecular typing techniques in epidemiological investigations has provided new tools for identifying the microorganism's origin and routes of dissemination. One of the most important conclusions that have resulted from these types of studies is that a small number of clones are responsible for most of the staphylococcal infections throughout the world.

Bats are rare reservoirs of Staphylococcus aureus complex in Gabon.

Science.gov (United States)

Held, Jana; Gmeiner, Markus; Mordmüller, Benjamin; Matsiégui, Pierre-Blaise; Schaer, Juliane; Eckerle, Isabella; Weber, Natalie; Matuschewski, Kai; Bletz, Stefan; Schaumburg, Frieder

2017-01-01

The colonization of afro-tropical wildlife with Staphylococcus aureus and the derived clade Staphylococcus schweitzeri remains largely unknown. A reservoir in bats could be of importance since bats and humans share overlapping habitats. In addition, bats are food sources in some African regions and can be the cause of zoonotic diseases. Here, we present a cross-sectional survey employing pharyngeal swabs of captured and released bats (n=133) in a forest area of Gabon. We detected low colonization rates of S. aureus (4-6%) and S. schweitzeri (4%) in two out of four species of fruit bats, namely Rousettus aegyptiacus and Micropteropus pusillus, but not in insectivorous bats. Multilocus sequence typing showed that S. aureus from Gabonese bats (ST2984, ST3259, ST3301, ST3302) were distinct from major African human associated clones (ST15, ST121, ST152). S. schweitzeri from bats (ST1697, ST1700) clustered with S. schweitzeri from other species (bats, monkeys) from Nigeria and Côte d'Ivoire. In conclusion, colonization rates of bats with S. aureus and S. schweitzeri were low in our study. Phylogenetic analysis supports an intense geographical dispersal of S. schweitzeri among different mammalian wildlife hosts. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398.

Science.gov (United States)

Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

2016-05-01

The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1-5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

Transmission of methicillin-resistant Staphylococcus aureus to household contacts

NARCIS (Netherlands)

F.P.N. Mollema (Femke); J.H. Richardus (Jan Hendrik); M.D. Behrendt (Myra); N. Vaessen (Norbert); W. Lodder; W. Hendriks; H.A. Verbrugh (Henri); A. Voss (Andreas)

2010-01-01

textabstractThe frequency of and risk factors for methicillin-resistant Staphylococcus aureus (MRSA) transmission from a MRSA index person to household contacts were assessed in this prospective study. Between January 2005 and December 2007, 62 newly diagnosed MRSA index persons (46 patients and 16

Mixed Lactobacillus plantarum Strains Inhibit Staphylococcus aureus Induced Inflammation and Ameliorate Intestinal Microflora in Mice.

Science.gov (United States)

Ren, Dayong; Gong, Shengjie; Shu, Jingyan; Zhu, Jianwei; Rong, Fengjun; Zhang, Zhenye; Wang, Di; Gao, Liangfeng; Qu, Tianming; Liu, Hongyan; Chen, Ping

2017-01-01

Objective . Staphylococcus aureus is an important pathogen that causes intestinal infection. We examined the immunomodulatory function of single and mixed Lactobacillus plantarum strains, as well as their impacts on the structure of the microbiome in mice infected with Staphylococcus aureus . The experiment was divided into three groups: protection, treatment, and control. Serum IFN- γ and IL-4 levels, as well as intestinal sIgA levels, were measured during and 1 week after infection with Staphylococcus aureus with and without Lactobacillus plantarum treatment. We used 16s rRNA tagged sequencing to analyze microbiome composition. IFN- γ /IL-4 ratio decreased significantly from infection to convalescence, especially in the mixed Lactobacillus plantarum group. In the mixed Lactobacillus plantarum group the secretion of sIgA in the intestine of mice (9.4-9.7 ug/mL) was significantly higher than in the single lactic acid bacteria group. The dominant phyla in mice are Firmicutes , Bacteroidetes , and Proteobacteria . Treatment with mixed lactic acid bacteria increased the anti-inflammatory factor and the secretion of sIgA in the intestine of mice infected with Staphylococcus aureus and inhibited inflammation.

Staphylococcus aureus carriage among participants at the 13th European Congress of Clinical Microbiology and Infectious Diseases.

NARCIS (Netherlands)

Nulens, E.; Gould, I.; MacKenzie, F.; Deplano, A.; Cookson, B.; Alp, E.; Bouza, E.; Voss, A.

2005-01-01

The aim of this study was to measure the rate of Staphylococcus aureus nasal colonization among attendees of the 13th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), particularly with regard to methicillin-resistant (MRSA) strains. The 31.4% rate of Staphylococcus aureus

Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

NARCIS (Netherlands)

S. van den Berg (Sanne)

2015-01-01

markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are

Increasing rate of daptomycin non-susceptible strains of Staphylococcus aureus in patients with atopic dermatitis

Directory of Open Access Journals (Sweden)

Izabela Błażewicz

2017-12-01

Full Text Available Introduction : Daptomycin is a cyclic lipopeptide that is bactericidal against Staphylococcus aureus , including methicillin-resistant S. aureus (MRSA, vancomycin-intermediate S. aureus (VISA and vancomycin-resistant S. aureus (VRSA strains. Daptomycin exerts its antimicrobial effect by a calcium-dependent interaction with the cytoplasmic membrane resulting in depolarization, ion loss and rapid cell death. Unfortunately, loss of daptomycin susceptibility in S. aureus in the clinical setting has been noted. Aim : To evaluate the susceptibility profile to daptomycin among S. aureus strains isloted from patients with atopic dermatitis (AD. Another point was to correlate the results obtained by broth microdilution method and Etest, which is commonly applied in clinical setting. Material and methods : One hundred patients with the diagnosis of atopic dermatitis were microbiologically assessed for the carriage of S. aureus . Antimicrobial susceptibility tests were performed using broth-microdilution (BMD and Etests for daptomycin. Results : Staphylococcus aureus strains were isolated from the majority of our patients, either from the skin (73% or the anterior nares (75%. Six of the 100 nasal swabs (6% and 5 of the 100 skin swabs (5% were positive for methicillin-resistant Staphylococcus aureus (MRSA. A total of 81 of 148 (54.7% daptomycin non-susceptible isolates of S. aureus were identified by BMD. Only 19 of 81 were also classified as non-susceptible by Etest. Conclusions : Clinicians and microbiologists should be aware of the possibility of the emergence of daptomycin non-susceptibility (or increase in minimal inhibitory concentration during prolonged therapy and closely monitor the susceptibility of persisting isolates that might be recovered during therapy.

Mechanisms of antibiotic resistance in Staphylococcus aureus.

Science.gov (United States)

Pantosti, Annalisa; Sanchini, Andrea; Monaco, Monica

2007-06-01

Staphylococcus aureus can exemplify better than any other human pathogen the adaptive evolution of bacteria in the antibiotic era, as it has demonstrated a unique ability to quickly respond to each new antibiotic with the development of a resistance mechanism, starting with penicillin and methicillin, until the most recent, linezolid and daptomycin. Resistance mechanisms include enzymatic inactivation of the antibiotic (penicillinase and aminoglycoside-modification enzymes), alteration of the target with decreased affinity for the antibiotic (notable examples being penicillin-binding protein 2a of methicillin-resistant S. aureus and D-Ala-D-Lac of peptidoglycan precursors of vancomycin-resistant strains), trapping of the antibiotic (for vancomycin and possibly daptomycin) and efflux pumps (fluoroquinolones and tetracycline). Complex genetic arrays (staphylococcal chromosomal cassette mec elements or the vanA operon) have been acquired by S. aureus through horizontal gene transfer, while resistance to other antibiotics, including some of the most recent ones (e.g., fluoroquinolones, linezolid and daptomycin) have developed through spontaneous mutations and positive selection. Detection of the resistance mechanisms and their genetic basis is an important support to antibiotic susceptibility surveillance in S. aureus.

Evaluation of Approaches to Monitor Staphylococcus aureus Virulence Factor Expression during Human Disease

OpenAIRE

Rozemeijer, Wouter; Fink, Pamela; Rojas, Eduardo; Jones, C. Hal; Pavliakova, Danka; Giardina, Peter; Murphy, Ellen; Liberator, Paul; Jiang, Qin; Girgenti, Douglas; Peters, Remco P. H.; Savelkoul, Paul H. M.; Jansen, Kathrin U.; Anderson, Annaliesa S.; Kluytmans, Jan

2015-01-01

Staphylococcus aureus is a versatile pathogen of medical significance, using multiple virulence factors to cause disease. A prophylactic S. aureus 4-antigen (SA4Ag) vaccine comprising capsular polysaccharide (types 5 and 8) conjugates, clumping factor A (ClfA) and manganese transporter C (MntC) is under development. This study was designed to characterize S. aureus isolates recovered from infected patients and also to investigate approaches for examining expression of S. aureus vaccine candid...

Role of ArlRS in autolysis in methicillin-sensitive and methicillin-resistant Staphylococcus aureus strains.

Science.gov (United States)

Memmi, Guido; Nair, Dhanalakshmi R; Cheung, Ambrose

2012-02-01

Autolysis plays an essential role in bacterial cell division and lysis with β-lactam antibiotics. Accordingly, the expression of autolysins is tightly regulated by several endogenous regulators, including ArlRS, a two component regulatory system that has been shown to negatively regulate autolysis in methicillin-sensitive Staphylococcus aureus (MSSA) strains. In this study, we found that inactivation of arlRS does not play a role in autolysis of methicillin-resistant S. aureus (MRSA) strains, such as community-acquired (CA)-MRSA strains USA300 and MW2 or the hospital-acquired (HA)-MRSA strain COL. This contrasts with MSSA strains, including Newman, SH1000, RN6390, and 8325-4, where autolysis is affected by ArlRS. We further demonstrated that the striking difference in the roles of arlRS between MSSA and MRSA strains is not due to the methicillin resistance determinant mecA. Among known autolysins and their regulators, we found that arlRS represses lytN, while no effect was seen on atl, lytM, and lytH expression in both CA- and HA-MRSA strains. Transcriptional-fusion assays showed that the agr transcripts, RNAII and RNAIII, were significantly more downregulated in the arlRS mutant of MW2 than the MSSA strain Newman. Importantly, provision of agr RNAIII in trans to the MW2 arlRS mutant via a multicopy plasmid induced autolysis in this MRSA strain. Also, the autolytic phenotype in the arlRS mutant of MSSA strain Newman could be rescued by a mutation in either atl or lytM. Together, these data showed that ArlRS impacts autolysis differently in MSSA and MRSA strains.

Staphylococcus aureus Nasal Colonization Differs among Pig Lineages and Is Associated with the Presence of Other Staphylococcal Species

Directory of Open Access Journals (Sweden)

Koen M. Verstappen

2017-06-01

Full Text Available Staphylococcus aureus is a common colonizer in pigs, with methicillin-resistant S. aureus (MRSA in particular being a potential health risk to humans. To reduce the exposure to humans, the colonization in pigs should be reduced. The aim of this study was to quantitatively compare the susceptibility of pig lineages for S. aureus colonization, and if the absence of S. aureus could be associated with the presence or absence of other staphylococcal species. Nasal samples (n = 129 were obtained from seven different pig lineages in the Netherlands, France, and Germany. S. aureus and other staphylococci were enumerated from these samples by real-time (RT-PCR and culture. Associations were explored between the presence of S. aureus and other staphylococci. S. aureus was detected by RT-PCR on all farms and in samples from pigs of all lineages. Twenty-five percent of the pigs from lineage F (from two farms were colonized with S. aureus, while in all other lineages it was more than 50% (p < 0.01. Moreover, in S. aureus-positive samples from pigs of lineage F smaller amounts of S. aureus were found than in other lineages. Staphylococcus sciuri, Staphylococcus cohnii, and Staphylococcus saprophyticus were usually not found in combination with S. aureus in these samples. In conclusion: (i pigs from different genetic lineages have different susceptibilities for colonization with S. aureus. These pigs might contain a genetic factor influencing nasal colonization. (ii Colonization of S. aureus is also associated with the absence of S. sciuri, S. cohnii, or S. saprophyticus. (iii The farm environment seems to influence the presence of S. aureus in pigs.

Genetic diversity of Staphylococcus aureus in Buruli ulcer.

Directory of Open Access Journals (Sweden)

Nana Ama Amissah

2015-02-01

Full Text Available Buruli ulcer (BU is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present study was therefore aimed at investigating the diversity and topography of S. aureus colonizing BU patients during treatment.We investigated the presence, diversity, and spatio-temporal distribution of S. aureus in 30 confirmed BU patients from Ghana during treatment. S. aureus was isolated from nose and wound swabs, and by replica plating of wound dressings collected bi-weekly from patients. S. aureus isolates were characterized by multiple-locus variable number tandem repeat fingerprinting (MLVF and spa-typing, and antibiotic susceptibility was tested.Nineteen (63% of the 30 BU patients tested positive for S. aureus at least once during the sampling period, yielding 407 S. aureus isolates. Detailed analysis of 91 isolates grouped these isolates into 13 MLVF clusters and 13 spa-types. Five (26% S. aureus-positive BU patients carried the same S. aureus genotype in their anterior nares and wounds. S. aureus isolates from the wounds of seven (37% patients were distributed over two different MLVF clusters. Wounds of three (16% patients were colonized with isolates belonging to two different genotypes at the same time, and five (26% patients were colonized with different S. aureus types over time. Five (17% of the 30 included BU patients tested positive for methicillin-resistant S. aureus (MRSA.The present study showed that the wounds of many BU patients were contaminated with S. aureus, and that many BU patients from the different communities carried the same S. aureus genotype during treatment. This calls for improved wound care and hygiene.

Genetic diversity of Staphylococcus aureus in Buruli ulcer.

Science.gov (United States)

Amissah, Nana Ama; Glasner, Corinna; Ablordey, Anthony; Tetteh, Caitlin S; Kotey, Nana Konama; Prah, Isaac; van der Werf, Tjip S; Rossen, John W; van Dijl, Jan Maarten; Stienstra, Ymkje

2015-02-01

Buruli ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present study was therefore aimed at investigating the diversity and topography of S. aureus colonizing BU patients during treatment. We investigated the presence, diversity, and spatio-temporal distribution of S. aureus in 30 confirmed BU patients from Ghana during treatment. S. aureus was isolated from nose and wound swabs, and by replica plating of wound dressings collected bi-weekly from patients. S. aureus isolates were characterized by multiple-locus variable number tandem repeat fingerprinting (MLVF) and spa-typing, and antibiotic susceptibility was tested. Nineteen (63%) of the 30 BU patients tested positive for S. aureus at least once during the sampling period, yielding 407 S. aureus isolates. Detailed analysis of 91 isolates grouped these isolates into 13 MLVF clusters and 13 spa-types. Five (26%) S. aureus-positive BU patients carried the same S. aureus genotype in their anterior nares and wounds. S. aureus isolates from the wounds of seven (37%) patients were distributed over two different MLVF clusters. Wounds of three (16%) patients were colonized with isolates belonging to two different genotypes at the same time, and five (26%) patients were colonized with different S. aureus types over time. Five (17%) of the 30 included BU patients tested positive for methicillin-resistant S. aureus (MRSA). The present study showed that the wounds of many BU patients were contaminated with S. aureus, and that many BU patients from the different communities carried the same S. aureus genotype during treatment. This calls for improved wound care and hygiene.

Isolation and identification of antibiotic resistance genes in Staphylococcus aureus isolates from respiratory system infections in shahrekord, Iran

Directory of Open Access Journals (Sweden)

Maryam Reisi

2014-07-01

Full Text Available   Introduction : Staphylococcus aureus is considered as one of pathogenic agents in humans, that engages different body parts including respiratory system and causes to spend lots of costs and extending patient’s treatment period. This study which is performed to separate and investigate the pattern of antibiotic resistance in Staphylococcus aureus isolates from upper respiratory system infections in Shahrekord.   Materials and methods: This study was done by sectional-descriptive method On 200 suspicious persons to the upper respiratory system infections who were referred to the Imam Ali clinic in Shahrekord in 2012. After isolation of Staphylococcus aureus from cultured nose discharges, antibiotic resistance genes were identified by polymerase chain reaction (PCR by using defined primer pairs .   Results : Among 200 investigated samples in 60 cases (30% Staphylococcus aureus infection (by culturing and PCR method was determined. Isolates showed the lowest amount of antibiotic resistance to vancomycin (0.5% and the highest amount of resistance to the penicillin G and cefotaxime (100%. mecA gene (encoding methicillin resistance with frequency of 85.18% and aacA-D gene (encoding resistance to aminoglycosides with frequency of 28.33% showed the highest and lowest frequency of antibiotic resistance genes coding in Staphylococcus aureus isolates respectively .   Discussion and conclusion : Notable prevalence of resistant Staphylococcus aureus isolates in community acquired respiratory infections, recommend continuous control necessity to impede the spreading of these bacteria and their infections.  

Methicillin-resistant Staphylococcus aureus in North-east Croatia

Directory of Open Access Journals (Sweden)

Tajana Pastuović

2015-05-01

Full Text Available Objective. The aim of this 5-year study was to determine the frequency and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA-related infections at Osijek Clinical Hospital. Materials and methods. A total of 1987 staphylococci-infected clinical isolates were collected and analysed at the Microbiology Department of the Public Health Institute of Osijek-Baranja County. Results. Between 2008 and 2012, the average rate of MRSA-related infections in staphylococci-infected patients was 27.4%. The proportion of MRSArelated infections on all Staphylococcus aureus (S. aureus isolates from clinical specimens showed a decreasing trend, from 32.6% in 2008 to 25.5% in 2012. MRSA-related infections were mostly detected in wound swabs (50.6% and aspirates (28.8% of patients hospitalized in the surgical (49.8% and intensive care units (27.9%. MRSA-related infection showed an increase compared to S. aureus-infections in samples of wounds and aspirates in 2011 and 2012 (57.9%/34.9% and 35.2%/16.3%, respectively. The majority of strains of MRSA-related infections were resistant to several antibiotics, including erythromycin and clindamycin, where susceptibility were less than 10%. All MRSA isolates were susceptible to vancomycin, teicoplanin and linezolid. Therefore, antibiotic therapies for MRSA infections include vancomycin, teicoplanin and linezolid, but microbiological diagnostics need to be performed in order to know when the use of glycopeptides and oxazolidinones is indicated. Conclusion. Our results suggest that appropriate prevention measures, combined with the more rational use of antibiotics are crucial to reduce the spread of MRSA-related infection in healthcare settings. Further monitoring is necessary of the incidence and antibiotic susceptibility of MRSA-related infections in our community.

Methicillin resistance in Staphylococcus aureus : a review of the ...

African Journals Online (AJOL)

Methicillin resistance in Staphylococcus aureus : a review of the molecular epidemiology, clinical significance and laboratory detection methods. ... Added to this burden is the emergence of more virulent strains of community-associated MRSA (CAMRSA) which at the turn of the century, has been increasingly reported to ...

Molecular Characterization of Endocarditis-Associated Staphylococcus aureus

Science.gov (United States)

Nethercott, Cara; Mabbett, Amanda N.; Totsika, Makrina; Peters, Paul; Ortiz, Juan C.; Nimmo, Graeme R.; Coombs, Geoffrey W.

2013-01-01

Infective endocarditis (IE) is a life-threatening infection of the heart endothelium and valves. Staphylococcus aureus is a predominant cause of severe IE and is frequently associated with infections in health care settings and device-related infections. Multilocus sequence typing (MLST), spa typing, and virulence gene microarrays are frequently used to classify S. aureus clinical isolates. This study examined the utility of these typing tools to investigate S. aureus epidemiology associated with IE. Ninety-seven S. aureus isolates were collected from patients diagnosed with (i) IE, (ii) bloodstream infection related to medical devices, (iii) bloodstream infection not related to medical devices, and (iv) skin or soft-tissue infections. The MLST clonal complex (CC) for each isolate was determined and compared to the CCs of members of the S. aureus population by eBURST analysis. The spa type of all isolates was also determined. A null model was used to determine correlations of IE with CC and spa type. DNA microarray analysis was performed, and a permutational analysis of multivariate variance (PERMANOVA) and principal coordinates analysis were conducted to identify genotypic differences between IE and non-IE strains. CC12, CC20, and spa type t160 were significantly associated with IE S. aureus. A subset of virulence-associated genes and alleles, including genes encoding staphylococcal superantigen-like proteins, fibrinogen-binding protein, and a leukocidin subunit, also significantly correlated with IE isolates. MLST, spa typing, and microarray analysis are promising tools for monitoring S. aureus epidemiology associated with IE. Further research to determine a role for the S. aureus IE-associated virulence genes identified in this study is warranted. PMID:23616460

Molecular characterization of endocarditis-associated Staphylococcus aureus.

Science.gov (United States)

Nethercott, Cara; Mabbett, Amanda N; Totsika, Makrina; Peters, Paul; Ortiz, Juan C; Nimmo, Graeme R; Coombs, Geoffrey W; Walker, Mark J; Schembri, Mark A

2013-07-01

Infective endocarditis (IE) is a life-threatening infection of the heart endothelium and valves. Staphylococcus aureus is a predominant cause of severe IE and is frequently associated with infections in health care settings and device-related infections. Multilocus sequence typing (MLST), spa typing, and virulence gene microarrays are frequently used to classify S. aureus clinical isolates. This study examined the utility of these typing tools to investigate S. aureus epidemiology associated with IE. Ninety-seven S. aureus isolates were collected from patients diagnosed with (i) IE, (ii) bloodstream infection related to medical devices, (iii) bloodstream infection not related to medical devices, and (iv) skin or soft-tissue infections. The MLST clonal complex (CC) for each isolate was determined and compared to the CCs of members of the S. aureus population by eBURST analysis. The spa type of all isolates was also determined. A null model was used to determine correlations of IE with CC and spa type. DNA microarray analysis was performed, and a permutational analysis of multivariate variance (PERMANOVA) and principal coordinates analysis were conducted to identify genotypic differences between IE and non-IE strains. CC12, CC20, and spa type t160 were significantly associated with IE S. aureus. A subset of virulence-associated genes and alleles, including genes encoding staphylococcal superantigen-like proteins, fibrinogen-binding protein, and a leukocidin subunit, also significantly correlated with IE isolates. MLST, spa typing, and microarray analysis are promising tools for monitoring S. aureus epidemiology associated with IE. Further research to determine a role for the S. aureus IE-associated virulence genes identified in this study is warranted.

Neutrophil evasion strategies by Streptococcus pneumoniae and Staphylococcus aureus.

Science.gov (United States)

Lewis, Megan L; Surewaard, Bas G J

2018-03-01

Humans are well equipped to defend themselves against bacteria. The innate immune system employs diverse mechanisms to recognize, control and initiate a response that can destroy millions of different microbes. Microbes that evade the sophisticated innate immune system are able to escape detection and could become pathogens. The pathogens Streptococcus pneumoniae and Staphylococcus aureus are particularly successful due to the development of a wide variety of virulence strategies for bacterial pathogenesis and they invest significant efforts towards mechanisms that allow for neutrophil evasion. Neutrophils are a primary cellular defense and can rapidly kill invading microbes, which is an indispensable function for maintaining host health. This review compares the key features of Streptococcus pneumoniae and Staphylococcus aureus in epidemiology, with a specific focus on virulence mechanisms utilized to evade neutrophils in bacterial pathogenesis. It is important to understand the complex interactions between pathogenic bacteria and neutrophils so that we can disrupt the ability of pathogens to cause disease.

Epidemiology of Streptococcus pneumoniae and Staphylococcus aureus colonization in healthy Venezuelan children

OpenAIRE

Quintero, B.; Araque, M.; van der Gaast-de Jongh, C.; Escalona, F.; Correa, M.; Morillo-Puente, S.; Vielma, S.; Hermans, P. W. M.

2010-01-01

Streptococcus pneumoniae and Staphylococcus aureus cause significant morbidity and mortality worldwide. We investigated both the colonization and co-colonization characteristics for these pathogens among 250 healthy children from 2 to 5?years of age in Merida, Venezuela, in 2007. The prevalence of S. pneumoniae colonization, S. aureus colonization, and S. pneumoniae?S. aureus co-colonization was 28%, 56%, and 16%, respectively. Pneumococcal serotypes 6B (14%), 19F (12%), 23F (12%), 15 (9%), 6...

Staphylococcus aureus biofilms: recent developments in biofilm dispersal.

Science.gov (United States)

Lister, Jessica L; Horswill, Alexander R

2014-01-01

Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment to medical implants and host tissue, and the establishment of a mature biofilm, play an important role in the persistence of chronic infections. The formation of a biofilm, and encasement of cells in a polymer-based matrix, decreases the susceptibility to antimicrobials and immune defenses, making these infections difficult to eradicate. During infection, dispersal of cells from the biofilm can result in spread to secondary sites and worsening of the infection. In this review, we discuss the current understanding of the pathways behind biofilm dispersal in S. aureus, with a focus on enzymatic and newly described broad-spectrum dispersal mechanisms. Additionally, we explore potential applications of dispersal in the treatment of biofilm-mediated infections.

Epidemic Increase in Methicillin-resistant Staphylococcus aureus in Copenhagen

DEFF Research Database (Denmark)

Westh, Henrik; Boye, Kit; Bartels, Mette Damkjær

2006-01-01

INTRODUCTION: We have found an epidemic increase in methicillin-resistant Staphylococcus aureus (MRSA) in Copenhagen. The increase has a complex background and involves hospitals, nursing homes and persons nursed in their own home. MATERIAL AND METHODS: We found 33 MRSA patients in 2003 and 121...... in 2004. All isolates have been spa-typed and epidemiologic information collected. RESULTS: The number of MRSA cases has a doubling time of about six months. The epidemic has been caused by many different MRSA types and 31 staphylococcus protein A genotypes (spa types). MRSA has caused several hospital...

Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

Directory of Open Access Journals (Sweden)

Jaime Canovas

2016-11-01

Full Text Available Staphylococci are associated with both humans and animals. While most are non-pathogenic colonizers, Staphylococcus aureus is an opportunistic pathogen capable of causing severe infections. S. aureus virulence is controlled by the agr quorum sensing system responding to secreted auto-inducing peptides (AIPs sensed by AgrC, a two component histidine kinase. agr loci are found also in other staphylococcal species and for Staphylococcus epidermidis, the encoded AIP represses expression of agr regulated virulence genes in S. aureus. In this study we aimed to better understand the interaction between staphylococci and S. aureus, and show that this interaction may eventually lead to the identification of new anti-virulence candidates to target S. aureus infections. Here we show that culture supernatants of 37 out of 52 staphylococcal isolates representing 17 different species inhibit S. aureus agr. The dog pathogen, Staphylococcus schleiferi, expressed the most potent inhibitory activity and was active against all four agr classes found in S. aureus. By employing a S. aureus strain encoding a constitutively active AIP receptor we show that the activity is mediated via agr. Subsequent cloning and heterologous expression of the S. schleiferi AIP in S. aureus demonstrated that this molecule was likely responsible for the inhibitory activity, and further proof was provided when pure synthetic S. schleiferi AIP was able to completely abolish agr induction of an S. aureus reporter strain. To assess impact on S. aureus virulence, we co-inoculated S. aureus and S. schleiferi in vivo in the Galleria mellonella wax moth larva, and found that expression of key S. aureus virulence factors was abrogated. Our data show that the S. aureus agr locus is highly responsive to other staphylococcal species suggesting that agr is an inter-species communication system. Based on these results we speculate that interactions between S. aureus and other colonizing staphylococci

Transposon mutagenesis identifies novel genes associated with Staphylococcus aureus persister formation

Directory of Open Access Journals (Sweden)

Wang ewenjie

2015-12-01

Full Text Available Pathogenic bacterial persisters are responsible for the recalcitrance of chronic and persistent infections to antimicrobial therapy. Although the mechanisms of persister formation and survival have been widely studied in Escherichia coli, persistence mechanisms in S. aureus remain largely unknown. Here, we screened a transposon mutant library of a clinical methicillin-resistant Staphylococcus aureus（MRSA）strain, USA500 (ST8, under antibiotic pressure and identified 13 genes whose insertion mutations resulted in a defect in persistence. These candidate genes were further confirmed by evaluating the survival of the mutants upon exposure to levofloxacin and several other stress conditions. We found 13 insertion mutants with significantly lower persister numbers under several stress conditions, including sdhA, sdhB, ureG, mnhG1, fbaA, ctaB, clpX, parE, HOU_0223, HOU_0587, HOU_2091, HOU_2315 and HOU_2346, which mapped into pathways of oxidative phosphorylation, TCA cycle, glycolysis, cell cycle and ABC transporters, suggesting that these genes and pathways may play an important role in persister formation and survival. The newly constructed knockout strains of ureG, sdhA and sdhB and their complemented strains were also tested for defect in persisters following exposure to levofloxacin and several other stress conditions. The results from these experiments were consistent with the screening results, which indicated that deletion of these genes in MRSA USA500 leads to persister defect. These findings provide novel insights into the mechanisms of persister formation and survival in S. aureus and offer new targets for the development of persister-directed antibiotics for the improved treatment of chronic and persistent infections.

Antimicrobials from human skin commensal bacteria protect against Staphylococcus aureus and are deficient in atopic dermatitis

Science.gov (United States)

Nakatsuji, Teruaki; Chen, Tiffany H.; Narala, Saisindhu; Chun, Kimberly A.; Two, Aimee M.; Yun, Tong; Shafiq, Faiza; Kotol, Paul F.; Bouslimani, Amina; Melnik, Alexey V.; Latif, Haythem; Kim, Ji-Nu; Lockhart, Alexandre; Artis, Keli; David, Gloria; Taylor, Patricia; Streib, Joanne; Dorrestein, Pieter C.; Grier, Alex; Gill, Steven R.; Zengler, Karsten; Hata, Tissa R.; Leung, Donald Y. M.; Gallo, Richard L.

2017-01-01

The microbiome can promote or disrupt human health by influencing both adaptive and innate immune functions. We tested whether bacteria that normally reside on human skin participate in host defense by killing Staphylococcus aureus, a pathogen commonly found in patients with atopic dermatitis (AD) and an important factor that exacerbates this disease. High-throughput screening for antimicrobial activity against S.aureus was performed on isolates of coagulase-negative Staphylococcus (CoNS) collected from the skin of healthy and AD subjects. CoNS strains with antimicrobial activity were common on the normal population but rare on AD subjects. A low frequency of strains with antimicrobial activity correlated with colonization by S.aureus. The antimicrobial activity was identified as previously unknown antimicrobial peptides (AMPs) produced by CoNS species including Staphylococcus epidermidis and Staphylococcus hominis. These AMPs were strain-specific, highly potent, selectively killed S.aureus, and synergized with the human AMP LL-37. Application of these CoNS strains to mice confirmed their defense function in vivo relative to application of nonactive strains. Strikingly, reintroduction of antimicrobial CoNS strains to human subjects with AD decreased colonization by S.aureus. These findings show how commensal skin bacteria protect against pathogens and demonstrate how dysbiosis of the skin microbiome can lead to disease. PMID:28228596

Silver nanoparticles for the inhibition of Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Miguel Ángel Ortiz-Gila

2015-01-01

Full Text Available Existe un gran ecosistema microbiano en la cavidad oral donde Staphylococcus aureus ( S. aureus se puede encontrar, causando patologías orales tales como quelitis angular, las paperas y la mucositis estafilocócica. Estas enfermedades producidas por S. aureus en la cavidad oral son consecuencia de los factores de virulencia, toxinas y multiresistencia a los antibióticos, lo que contribuye a la infección. La colonización en la cavidad oral por S. aureus en pacientes sanos es de 24% a 36%. Sin embargo, la incidencia aumenta a 48% en pacientes con prótesis debido a la formación de biofilms en la superficie de las dentaduras postizas. Actualmente, no existe ningún tratamiento para infecciones orales sin el uso de antibióticos. Investigaciones recientes indican que las nanopartículas de plata (AgNPs son un material o estrategia para eliminar S. aureus debido a su efecto antibacteriano. Sin embargo, el mecanismo del efecto inhibidor de los iones de Ag sobre S. aureus es sólo parcialmente conocida y muy poco se ha informado. Por lo tanto, el propósito de la presente revisión sistemática es determinar las estrategias y retos de la utilización de biomateriales antimicrobianos con AgNPs frente a las infecciones orales de S. aureus.

Staphylococcus aureus panton-valentine leukocidin is a very potent cytotoxic factor for human neutrophils.

Directory of Open Access Journals (Sweden)

Bettina Löffler

2010-01-01

Full Text Available The role of the pore-forming Staphylococcus aureus toxin Panton-Valentine leukocidin (PVL in severe necrotizing diseases is debated due to conflicting data from epidemiological studies of community-associated methicillin-resistant S. aureus (CA-MRSA infections and various murine disease-models. In this study, we used neutrophils isolated from different species to evaluate the cytotoxic effect of PVL in comparison to other staphylococcal cytolytic components. Furthermore, to study the impact of PVL we expressed it heterologously in a non-virulent staphylococcal species and examined pvl-positive and pvl-negative clinical isolates as well as the strain USA300 and its pvl-negative mutant. We demonstrate that PVL induces rapid activation and cell death in human and rabbit neutrophils, but not in murine or simian cells. By contrast, the phenol-soluble modulins (PSMs, a newly identified group of cytolytic staphylococcal components, lack species-specificity. In general, after phagocytosis of bacteria different pvl-positive and pvl-negative staphylococcal strains, expressing a variety of other virulence factors (such as surface proteins, induced cell death in neutrophils, which is most likely associated with the physiological clearing function of these cells. However, the release of PVL by staphylococcal strains caused rapid and premature cell death, which is different from the physiological (and programmed cell death of neutrophils following phagocytosis and degradation of virulent bacteria. Taken together, our results question the value of infection-models in mice and non-human primates to elucidate the impact of PVL. Our data clearly demonstrate that PVL acts differentially on neutrophils of various species and suggests that PVL has an important cytotoxic role in human neutrophils, which has major implications for the pathogenesis of CA-MRSA infections.

Prevalence and molecular characterization of Staphylococcus aureus in commercially available meat over a one-year period in Iowa, USA.

Science.gov (United States)

Thapaliya, Dipendra; Forshey, Brett M; Kadariya, Jhalka; Quick, Megan K; Farina, Sarah; O' Brien, Ashley; Nair, Rajeshwari; Nworie, Amos; Hanson, Blake; Kates, Ashley; Wardyn, Shylo; Smith, Tara C

2017-08-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of infectious disease morbidity and mortality. Previous studies have confirmed the presence of S. aureus, including MRSA, on raw meat products. We investigated the prevalence and molecular epidemiology of S. aureus and MRSA in commercially-distributed antibiotic-free and conventional raw meat products (n = 3290) purchased in 8 Iowa retail stores weekly for a period of one year. Isolates were characterized using spa typing, and PCR was used to detect the presence of the Panton-Valentine leukocidin (PVL) and mecA genes. Quantitation of S. aureus on meat products was carried out one week per month. The prevalence of S. aureus on meat samples was 27.8% (913/3290). Compared to antibiotic-free meat samples, higher prevalence of both MRSA and methicillin-susceptible S. aureus (MSSA) were found in conventional meat samples. Among the S. aureus isolates, 18 were PVL-positive (1.9%) and 41 (4.5%) carried mecA. Phenotypic oxacillin resistance was observed for 17.1% (41/239) of the isolates tested, while 23% (55/239) were multi-drug resistant. A total of 132 spa types were detected from 913 contaminated meat samples. Overall, t002 was the most common spa type identified (137; 15.0%). The number of colony-forming units (CFU) per 10 g meat ranged from 2 to 517 (median: 8 CFU per 10 g of meat; mean: 28) with the highest bacterial load observed on turkey samples. These data reinforce the need to consider meat products as potential vehicles of S. aureus transmission from farm into human households, and the potential need for public health intervention programs pre and post-slaughter in meat processing facilities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Construction of Stable Fluorescent Reporter Plasmids for Use in Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Michelle D. Rodriguez

2017-12-01

Full Text Available Here, the genes encoding three different fluorescent proteins were cloned into the stably maintained Staphylococcus aureus shuttle vector pKK30. The resulting plasmids were transformed into two S. aureus strains; SH1000 and RN4220. Stability assays illustrated that the three recombinant plasmids retained near 100% maintenance in vitro for 160 generations. S. aureus strain SH1000 expressing green fluorescent protein was then inoculated in an ovine model and in vivo stability for 6 days was demonstrated. In essence, these reporter plasmids represent a useful set of tools for dynamic imaging studies in S. aureus. These three reporter plasmids are available through BEI Resources.

Construction of Stable Fluorescent Reporter Plasmids for Use in Staphylococcus aureus.

Science.gov (United States)

Rodriguez, Michelle D; Paul, Zubin; Wood, Charles E; Rice, Kelly C; Triplett, Eric W

2017-01-01

Here, the genes encoding three different fluorescent proteins were cloned into the stably maintained Staphylococcus aureus shuttle vector pKK30. The resulting plasmids were transformed into two S. aureus strains; SH1000 and RN4220. Stability assays illustrated that the three recombinant plasmids retained near 100% maintenance in vitro for 160 generations. S. aureus strain SH1000 expressing green fluorescent protein was then inoculated in an ovine model and in vivo stability for 6 days was demonstrated. In essence, these reporter plasmids represent a useful set of tools for dynamic imaging studies in S. aureus . These three reporter plasmids are available through BEI Resources.

The Pre - Eminence of Staphylococcus Aureus as The Causative ...

African Journals Online (AJOL)

A range of infections is caused by Staphylococcal organisms prominent among them are nosocomial superficial infections manifesting as abscesses, furuncles, and wound infections. The study objective is to determine the degree to which Staphylococcus aureus is a cause of such lesions in a tertiary health care institution ...

Pitfalls in the routine diagnosis of Staphylococcus aureus | Bello ...

African Journals Online (AJOL)

Two hundred isolates of Presumed Staphylococcus aureus from routine clinical specimens, collected from two government hospitals in Abha, Saudi Arabia, had their identity verified. We used the tube coagulase test as our gold standard. Twenty (10%) of the isolates were mis-identified. Reliance by the two laboratories on ...

Retrospective Study on the Prevalence and Antibiotic Resistance Pattern of Staphylococcus Aureus and Staphylococcus Epidermidis Among Patients Suspicious of Bacteremia During 2006 - 2011

Directory of Open Access Journals (Sweden)

Mohammad Ali Mohaghegh

2015-05-01

Full Text Available Background: Staphylococci bacteria cause different diseases, varies from mild skin infections to serious bacteremia. Also they are a major cause of nosocomial and community-acquired infections globally. Staphylococcus aureus and Staphylococcus epidermidis are the two important opportunistic pathogens of the staphylococci that both can cause bacteremia. Objectives: The aim of the present study was to investigate the prevalence and antibiotic resistance pattern of S. aureus and S. epidermidis among blood culture of patients of Ghaem Educational, Research and Treatment Center, Mashhad, Iran, during 6 years (2006 - 2011. Patients and Methods: In this retrospective study, hospital medical records of 28000 patients referred to Ghaem Educational, Research and Treatment Center, Mashhad, Iran, who were suspicious of blood infections during 6 years (2005-2011, were extracted. The patient’s blood culture with staphylococcal growth and their antibiogram results during 2006 - 2011 were collected and studied. Results: Staphylococcus spp. were isolated from 600 (2.14% out of 28000 blood cultures. Furthermore, 420 (70%, 170 (28.3% and 10 (1.7% out of 600 bacterial isolates identified as S. epidermidis, S. aureus and other Staphylococcus spp., respectively. Ampicillin, amoxicillin, cefixime, ceftazidime, penicillin, oxacillin, nalidixic acid and cephepime were the most antibiotics that the isolates were resistant against. Also vancommycin and chloramphenicol were the most effective antibiotics against S. epidermidis and S. aureus, respectively. Conclusions: Prevalence of Staphylococcal bacteremia caused by S. epidermidis is fairly high comparing to S. aureus among patients referred to Ghaem Educational, Research and Treatment Center, Mashhad, Iran. Also the resistance rate of Staphylococcus spp. isolated from blood against commonly used antibiotic is high, but there are some highly sensitive antibiotic against the infection.

Epidemiology of drug resistance: The case of Staphylococcus aureus and coagulase-negative staphylococci infections Epidemiología de la resistencia bacteriana: el caso de Staphylococcus aureus y las infecciones Staphylococcus coagulasa negativas

Directory of Open Access Journals (Sweden)

Ernesto Calderón-Jaimes

2002-04-01

Full Text Available Objective. To study the activity of several antibiotics against Staphylococcus spp. Material and Methods. The study included 1209 strains of Staphylococcus spp. from two institutions; Instituto Nacional de Pediatría (National Institute of Pediatrics and Hospital Infantil de México Federico Gómez (Mexico City Children's Hospital. Minimum Inhibitory Concentrations of all antibiotics were determined by the agar macrodilution technique and standard methods from the National Committee for Clinical Laboratory Standards. Results. Resistance of S. aureus was 14.2% and that of coagulase-negative staphylococci was 53.4%. The activity of different antibiotics is presented in detail. Conclusions. Surveillance of strains resistant to methicillin is necessary.Objetivo. Determinar la frecuencia de la resistencia a la meticilina y la actividad de varios antibióticos. Material y métodos. Se incluyeron 1 209 cepas de Staphylococcus spp. procedentes de pacientes del Instituto Nacional de Pediatría y del Hospital Infantil de México Federico Gómez. Se utilizó la técnica de dilución en placas con agar. El procedimiento e interpretación fueron acordes con lo establecido por el National Committee for Clinical Laboratory Standards. Resultados. La frecuencia de la resistencia de S. aureus fue de 14.2% y de 53.4% en los Staphylococcus coagulasa negativa. La actividad de otros antimicrobianos se presenta en el texto. Conclusiones. Es necesario vigilar continuamente la progresión de la resistencia de Staphylococcus spp. a la meticilina.

Risk factors associated with the antimicrobial resistance of Staphylococcus aureus isolated from bovine mastitis

Directory of Open Access Journals (Sweden)

Daniele C. Beuron

2014-10-01

Full Text Available The objective of this study was to evaluate herd management practices and mastitis treatment procedures as risk factors associated with Staphylococcus aureus antimicrobial resistance. For this study, 13 herds were selected to participate in the study to evaluate the association between their management practices and mastitis treatment procedures and in vitro antimicrobial susceptibility. A total of 1069 composite milk samples were collected aseptically from the selected cows in four different periods over two years. The samples were used for microbiological culturing of S. aureus isolates and evaluation of their antimicrobial susceptibility. A total of 756 samples (70.7% were culture-positive, and S. aureus comprised 27.77% (n=210 of the isolates. The S. aureus isolates were tested using the disk-diffusion susceptibility assay with the following antimicrobials: ampicillin 10mg; clindamycin 2μg; penicillin 1mg; ceftiofur 30μg; gentamicin 10mg; sulfa-trimethoprim 25μg; enrofloxacin 5μg; sulfonamide 300μg; tetracycline 30μg; oxacillin 1mg; cephalothin 30μg and erythromycin 5μg. The variables that were significantly associated with S. aureus resistance were as follows: the treatment of clinical mastitis for ampicillin (OR=2.18, dry cow treatment for enrofloxacin (OR=2.11 and not sending milk samples for microbiological culture and susceptibility tests, for ampicillin (OR=2.57 and penicillin (OR=4.69. In conclusion, the identification of risk factors for S. aureus resistance against various mastitis antimicrobials is an important information that may help in practical recommendations for prudent use of antimicrobial in milk production.

'Prevalence and antimicrobial susceptibility of Listeria monocytogenes and methicillin-resistant Staphylococcus aureus strains from raw meat and meat products in Zaria, Nigeria.

Science.gov (United States)

Ndahi, M D; Kwaga, J K P; Bello, M; Kabir, J; Umoh, V J; Yakubu, S E; Nok, A J

2014-03-01

The bacterial genera Listeria and Staphylococcus have been frequently isolated from food products and are responsible for a number of animal and human diseases. The aim of the study was to simultaneously isolate and characterize L. monocytogenes and Staphylococcus species from 300 samples of raw meat and meat products, to determine the susceptibility of the organisms to commonly used antimicrobial agents and to determine the presence of haemolysin A (hyl) virulence gene in L. monocytogenes and staphylococcal cassette chromosome mecA (SCCmec) gene in the Staph. aureus isolates using PCR. Of the 85 Listeria isolates tested, 12 L. monocytogenes were identified and tested for their sensitivity to 14 antimicrobial agents. All the 12 isolates (100%) were resistant to nine antimicrobial agents, but however sensitive to gentamicin. Only one isolate was found to harbour the hylA gene. Twenty-nine isolates were confirmed as Staph. aureus by the Microbact 12S identification system and were all presumptively identified as methicillin-resistant Staph. aureus species using oxacillin-resistant Staph. aureus basal medium (ORSAB). The 29 Staph. aureus isolates were tested for their sensitivity to 16 antimicrobial agents, and 11 were resistant to methicillin. None of the 11 Staph. aureus isolates harboured the methicillin resistance, mecA gene. Listeria monocytogenes and Staphylococcus aureus are important agents of foodborne diseases. Occurrence of these infectious agents was established in meat and meat products in Zaria, Nigeria. Majority of isolates obtained from this study, displayed multidrug resistance to commonly used antimicrobial agents, including methicillin resistance among the Staph. aureus isolates. The potential virulence of L. monocytogenes found in ready-to-eat food was documented by the carriage of hly A gene by one of the isolates. A different mechanism of methicillin resistance or different homologue of mec A gene may be circulating among Nigerian

Development of Single-Walled Carbon Nanotube-Based Biosensor for the Detection of Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Hyun-Kyung Choi

2017-01-01

Full Text Available The goal of this research is to develop a single-walled carbon nanotube- (SWCNT- based biosensor to detect Staphylococcus aureus. The specificity of 11 bacteria and polyclonal anti-Staphylococcus aureus antibodies (pAbs was determined using an indirect ELISA. The pAbs were immobilized onto sensor platform after the hybridization of 1-pyrenebutanoic acid succinimidyl ester (PBASE. The resistance difference (ΔR was calculated using a potentiostat. The bacteria detected by the biosensor were observed using a scanning electron microscope (SEM. The optimum concentration of SWCNTs on the platform was determined to be 0.1 mg/mL. The binding of pAbs with S. aureus resulted in a significant increase in resistance value of the biosensor (P<0.05. The SEM images confirmed the specific binding of S. aureus on the biosensor. The SWCNT-based biosensor was able to detect S. aureus with a limit of detection (LOD of 4 log⁡CFU/mL.

Evaluation of approaches to monitor Staphylococcus aureus virulence factor expression during human disease

NARCIS (Netherlands)

Rozemeijer, Wouter; Fink, Pamela; Rojas, Eduardo; Jones, C Hal; Pavliakova, Danka; Giardina, Peter; Murphy, Ellen; Liberator, Paul; Jiang, Qin; Girgenti, Douglas; Peters, Remco P H; Savelkoul, Paul H M; Jansen, Kathrin U; Anderson, Annaliesa S; Kluytmans, Jan

2015-01-01

Staphylococcus aureus is a versatile pathogen of medical significance, using multiple virulence factors to cause disease. A prophylactic S. aureus 4-antigen (SA4Ag) vaccine comprising capsular polysaccharide (types 5 and 8) conjugates, clumping factor A (ClfA) and manganese transporter C (MntC) is

Clonal diversity of Staphylococcus aureus originating from the small ruminants goats and sheep

DEFF Research Database (Denmark)

Concepción Porrero, M.; Hasman, Henrik; Vela, Ana I.

2012-01-01

Staphylococcus aureus is an important pathogen in humans and many animal species. The prevalence of different clonal types in animal species remains largely unknown. We analyzed 267 S. aureus from intramammary infections in goats (47) and sheep (220) by spa typing, multi-locus sequence typing (ML...

Increased risk of arterial thromboembolic events after Staphylococcus aureus bacteremia

DEFF Research Database (Denmark)

Mejer, N; Gotland, N; Uhre, M L

2015-01-01

OBJECTIVES: An association between infection and arterial thromboembolic events (ATE) has been suggested. Here we examined the risk of myocardial infarction (MI), stroke and other ATE after Staphylococcus aureus bacteremia (SAB). METHODS: Danish register-based nation-wide observational cohort study...

Comparison of four methods for rapid identification of Staphylococcus aureus directly from BACTEC 9240 blood culture system.

Science.gov (United States)

Ozen, N S; Ogunc, D; Mutlu, D; Ongut, G; Baysan, B O; Gunseren, F

2011-01-01

Differentiation of Staphylococcus aureus (S. aureus) from coagulase-negative staphylococci is very important in blood stream infections. Identification of S. aureus and coagulase-negative staphylococci (CoNS) from blood cultures takes generally 18-24 h after positive signaling on continuously monitored automated blood culture system. In this study, we evaluated the performance of tube coagulase test (TCT), slide agglutination test (Dry Spot Staphytect Plus), conventional polymerase chain reaction (PCR) and LightCycler Staphylococcus MGrade kit directly from blood culture bottles to achieve rapid identification of S. aureus by using the BACTEC 9240 blood culture system. A total of 129 BACTEC 9240 bottles growing gram-positive cocci suggesting Staphylococci were tested directly from blood culture broths (BCBs) with TCT, Dry Spot Staphytect Plus, conventional PCR and LightCycler Staphylococcus MGrade kit for rapid identification of S. aureus. The sensitivities of the tests were 99, 68, 99 and 100%, respectively. Our results suggested that 2 h TCT was found to be simple and inexpensive method for the rapid identification of S. aureus directly from positive blood cultures.

Metastatic Spreading of Community Acquired Staphylococcus aureus Bacteraemia

Directory of Open Access Journals (Sweden)

Giovanna Fabio

2011-01-01

Full Text Available A 29-year-old woman presented to the Fondazione IRCCS “Cà Granda” Ospedale Maggiore, a tertiary care university hospital in Milan (Italy, with skin lesions, fever, myalgia, joint pain and swelling, and a one-week history of low back pain. The diagnosis was Staphylococcus aureus (S. aureus bacteraemia spreading to skin, bones, and joints and a lumbosacral epidural abscess L5-S2. Neither initial focus nor predisposing conditions were apparent. The antibiotic therapy was prolonged for six-weeks with the resolution of fever, skin lesions, articular inflammation, and the epidural abscess. Community-acquired S. aureus infections can affect patients without traditional healthcare-associated risk factors, and community acquisition is a risk-factor for the development of complications. Raised awareness of S. aureus bacteraemia, also in patients without healthcare-associated risk factors, is important in the diagnosis, management, and control of this infection, because failure to recognise patients with serious infection and lack of understanding of empirical antimicrobial selection are associated with a high mortality rate in otherwise healthy people.

DAYA HAMBAT SARI TANAMAN OBAT TERHADAP PERTUMBUHAN BAKTERI STRAIN Methicillin Resistant Staphylococcus aureus (MRSA

Directory of Open Access Journals (Sweden)

Dwi Hilda Putri

2016-09-01

Full Text Available Staphylococcus aureus infection can be treated with Methicilin, β lactam class of antibiotics that have drug targets in the cell wall. Bacteria S. aureus that is resistant to methicillin called methicillin-resistant Staphylococcus aureus (MRSA. One alternative that can be used in strains of antibiotic-resistant bacteria that have this is to use medicinal plants. This study aimed to know the ability of medicinal plant extracts inhibit the growth of bacterial strains of MRSA. This kind of research is experimental research. Medicinal plants tested were Garlic, Turmeric, Aloe Vera, Daun Salam, Curcuma, Ginger, Betel Leaf and Alpinia galanga. As a control, which is used Amphicillin, β lactam antibiotic class. The method used to determine the diameter of inhibition area of medicinal plant extracts is paper diffusion method. The results showed that all medicinal plants can inhibit bacterial growth of MRSA strains characterized by the inhibition zone formed on each treatment. The ability of garlic and turmeric extract better than Amphicillin and other medicinal plants to inhibit bacterial growth of MRSA strains. Kata kunci: inhibit,  growth, bacteria, methicillin resistant staphylococcus aureus (MRSA

Lysionotin attenuates Staphylococcus aureus pathogenicity by inhibiting α-toxin expression.

Science.gov (United States)

Teng, Zihao; Shi, Dongxue; Liu, Huanyu; Shen, Ziying; Zha, Yonghong; Li, Wenhua; Deng, Xuming; Wang, Jianfeng

2017-09-01

α-Toxin, one of the best known pore-forming proteins produced by Staphylococcus aureus (S. aureus), is a critical virulence factor in multiple infections. The necessity of α-toxin for S. aureus pathogenicity suggests that this toxin is an important target for the development of a potential treatment strategy. In this study, we showed that lysionotin, a natural compound, can inhibit the hemolytic activity of culture supernatants by S. aureus by reducing α-toxin expression. Using real-time PCR analysis, we showed that transcription of hla (the gene encoding α-toxin) and agr (the locus regulating hla) was significantly inhibited by lysionotin. Lactate dehydrogenase and live/dead assays indicated that lysionotin effectively protected human alveolar epithelial cells against S. aureus, and in vivo studies also demonstrated that lysionotin can protect mice from pneumonia caused by S. aureus. These findings suggest that lysionotin is an efficient inhibitor of α-toxin expression and shows significant protection against S. aureus in vitro and in vivo. This study supports a potential strategy for the treatment of S. aureus infection by inhibiting the expression of virulence factors and indicates that lysionotin may be a potential treatment for S. aureus pneumonia.

PARTIAL CHARACTERIZATION OF A LYTIC METHICILLIN RESISTANT-STAPHYLOCOCCUS AUREUS BACTERIOPHAGE

Directory of Open Access Journals (Sweden)

Sulaiman Al-Yousef

2014-12-01

Full Text Available A marked increase in the infection incidence caused by methicillin-resistant Staphylococcus aureus (MRSA strains has been noted in medical practice in recent years. This study was conducted to study the biological and characterize of MRSA-phage. Methicillin resistance of Staphylococcus aureus was detected and confirmed by determining of the MIC of oxacillin by the standard agar dilution method. Phage was biologically purified using single plaque technique, then phage characterization were studied using host range, adsorption time, particle morphology and its structural protein. MRSA phage showing lytic nature was purified by repeated plating after picking of single isolated plaques. This phage is active against all 11 isolates either of S. aureus or MRSA tested as hosts. Phage produced clear plaques indicating their lytic nature. This phage was concentrated employing polyethylene glycol (PEG-NaCl precipitation method. Morphologically, MRSA Phage has a hexagonal head having a long non-contractile tail, indicating his icosahedral nature. Adsorption studies showed 100% adsorption of MRSA-Phage after 35 minutes of exposure. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE experimentation indicated that the phage particles contain one major structural protein (about 30 Kda.

Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

NARCIS (Netherlands)

Tulinski, P.; Duim, B.; Wittink, F.R.; Jonker, M.J.; Breit, T.M.; van Putten, J.P.; Wagenaar, J.A.; Fluit, A.C.

2014-01-01

Background: Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

NARCIS (Netherlands)

Tulinski, P.; Duim, B.; Wittink, F.R.; Jonker, M.J.; Breit, T.M.; Van Putten, J.P.; Wagenaar, J.A.; Fluit, A.C.

2014-01-01

Background Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

Staphylococcus aureus ST398 gene expression profiling during ex vivo colonization of porcine nasal epithelium

NARCIS (Netherlands)

Tulinski, Pawel; Duim, Birgitta; Wittink, Floyd R; Jonker, Martijs J; Breit, Timo M; van Putten, Jos P; Wagenaar, Jaap A; Fluit, Ad C

2014-01-01

BACKGROUND: Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig

Screening of medicinal plants for antibacterial activities on Staphylococcus aureus strains isolated from bovine mastitis Screening de plantas medicinais com atividade antimicrobiana contra cepas de Staphylococcus aureus isoladas de mastite bovina

Directory of Open Access Journals (Sweden)

Marisa A. N. Diaz

2010-11-01

Full Text Available Staphylococcus aureus is the main causative agent of bovine mastitis. The activity of several extracts from ten medicinal plants traditionally used in Brazil as antiseptic was investigated against fifteen strains of Staphylococcus aureus isolated from animals with mastitis manifestation by the disc diffusion method and broth microdilution assay. The interference of the extracts on cell in the form of adherent colonies was also evaluated. MIC values ranged from 0.5 mg/mL to 1.0 mg/mL and biofilm inhibitory concentration (BIC were between 0.25 mg/mL and 0.8 mg/mL. Results revealed the potential of extracts of Senna macranthera, Artemisia absinthium, Cymbopogon nardus and Baccharis dracunculifolia as antibacterial agents against S. aureus strains isolated from bovine mastitis and support the possible use of these phytotherapic agents in the clinical management of the disease.Staphylococcus aureus é o principal agente causador de mastite bovina. A atividade de diversos extratos de dez plantas medicinais tradicionalmente usadas no Brasil como anti-sépticas foi investigada contra quinze cepas de Staphylococcus aureus isoladas de animais com manifestação de mastite pelo método de difusão em ágar e ensaio de microdiluição. A interferência dos extratos na célula bacteriana em forma de colônias aderidas também foi avaliada. Os valores de MIC variaram de 0.5 mg/mL a 1.0 mg/mL e a concentração inibitória de biofilme (BIC variou de 0.25 mg/mL a 0.8 mg/mL. Os resultados revelaram o potencial dos extratos de Senna macranthera, Artemisia absinthium, Cymbopogon nardus e Baccharis dracunculifolia como agentes antibacterianos contra cepas de S. aureus isolados de mastite bovina e suportam o possível uso destas plantas no manejo clínico da doença.

Capturing of staphylococcus aureus onto an interface containing graft chains

International Nuclear Information System (INIS)

Lee, W.; Furusaki, Shintaro; Saito, Kyoichi; Sugo, Takanobu; Makuuchi, Keizo.

1995-01-01

A microbial-cell-capturing material was prepared by radiation-induced grafting of glycidyl methacrylate onto a polyethylene-based fiber before the introduction of diethylamine. The prepared fiber was tested against a Staphylococcus aureus and Escherichia coli solution. The results showed that the grafted-type fiber had a capturing rate constant 1000-fold higher than the commercial crosslinked-type bead for S. aureus and that an activation energy of 39 kJ/mol was obtained for the microbial-cell-capturing action. (author)

Semi Quantitative MALDI TOF for Antimicrobial Susceptibility Testing in Staphylococcus aureus

Science.gov (United States)

2017-08-31

Semi- quantitative MALDI-TOF for antimicrobial susceptibility testing in Staphylococcus 1 aureus 2 3 4 Tucker Maxson,a Cheryl L. Taylor-Howell,a...Timothy D. Minoguea# 5 6 Diagnostic Systems Division, United States Army Medical Research Institute of Infectious 7 Disease, Fort Detrick, MD...USAa 8 9 Running Title: Quantitative MALDI for AST in S. aureus 10 #Address correspondence to Timothy D. Minogue, timothy.d.minogue.civ@mail.mil

Characterization of staphylococci in urban wastewater treatment plants in Spain, with detection of methicillin resistant Staphylococcus aureus ST398

International Nuclear Information System (INIS)

Gómez, Paula; Lozano, Carmen; Benito, Daniel; Estepa, Vanesa; Tenorio, Carmen; Zarazaga, Myriam; Torres, Carmen

2016-01-01

The objective of this study was to determine the prevalence of Staphylococcus in urban wastewater treatment plants (UWTP) of La Rioja (Spain), and to characterize de obtained isolates. 16 wastewater samples (8 influent, 8 effluent) of six UWTPs were seeded on mannitol-salt-agar and oxacillin-resistance-screening-agar-base for staphylococci and methicillin-resistant Staphylococcus aureus recovery. Antimicrobial susceptibility profile was determined for 16 antibiotics and the presence of 35 antimicrobial resistance genes and 14 virulence genes by PCR. S. aureus was typed by spa, agr, and multilocus-sequence-typing, and the presence of immune-evasion-genes cluster was analyzed. Staphylococcus spp. were detected in 13 of 16 tested wastewater samples (81%), although the number of CFU/mL decreased after treatment. 40 staphylococci were recovered (1–5/sample), and 8 of them were identified as S. aureus being typed as (number of strains): spa-t011/agr-II/ST398 (1), spa-t002/agr-II/ST5 (2), spa-t3262/agr-II/ST5 (1), spa-t605/agr-II/ST126 (3), and spa-t878/agr-III/ST2849 (1). S. aureus ST398 strain was methicillin-resistant and showed a multidrug resistance phenotype. Virulence genes tst, etd, sea, sec, seg, sei, sem, sen, seo, and seu, were detected among S. aureus and only ST5 strains showed genes of immune evasion cluster. Thirty-two coagulase-negative Staphylococcus of 12 different species were recovered (number of strains): Staphylococcus equorum (7), Staphylococcus vitulinus (4), Staphylococcus lentus (4), Staphylococcus sciuri (4), Staphylococcus fleurettii (2), Staphylococcus haemolyticus (2), Staphylococcus hominis (2), Staphylococcus saprophyticus (2), Staphylococcus succinus (2), Staphylococcus capitis (1), Staphylococcus cohnii (1), and Staphylococcus epidermidis (1). Five presented a multidrug resistance phenotype. The following resistance and virulence genes were found: mecA, lnu(A), vga(A), tet(K), erm(C), msr(A)/(B), mph(C), tst, and sem. We found that

Staphylococcus aureus with Panton-Valentine toxin skin infection in a medical laboratory technician.

Science.gov (United States)

Pougnet, Richard; Pougnet, Laurence

2016-12-01

This report exposes the case of a Staphylococcus aureus infection occurring in a microbiology laboratory technician. He was a 52 year-old man without medical history. He presented an abscess on the anterior aspect of the left forearm. Analysis showed that it was a Staphylococcus aureus secreting the Panton-Valentine toxin. The study of the workplace found the frequency of exposure. The study of workstation showed the link between the technician position and the infection. Indeed, this man touched an area where the biocleaning was hard to do. This is the first case of infection with PVL described for a laboratory technician.

Non-spa-typeable clinical Staphylococcus aureus strains are naturally occurring protein A mutants

DEFF Research Database (Denmark)

Baum, Cathrin; Haslinger-Löffler, Bettina; Westh, Henrik

2009-01-01

Staphylococcus aureus is a major human pathogen responsible for increasing the prevalence of community- and hospital-acquired infections. Protein A (SpA) is a key virulence factor of S. aureus and is highly conserved. Sequencing of the variable-number tandem-repeat region of SpA (spa typing) prov...

Humanized Mouse Models of Staphylococcus aureus Infection

Directory of Open Access Journals (Sweden)

Dane Parker

2017-05-01

Full Text Available Staphylococcus aureus is a successful human pathogen that has adapted itself in response to selection pressure by the human immune system. A commensal of the human skin and nose, it is a leading cause of several conditions: skin and soft tissue infection, pneumonia, septicemia, peritonitis, bacteremia, and endocarditis. Mice have been used extensively in all these conditions to identify virulence factors and host components important for pathogenesis. Although significant effort has gone toward development of an anti-staphylococcal vaccine, antibodies have proven ineffective in preventing infection in humans after successful studies in mice. These results have raised questions as to the utility of mice to predict patient outcome and suggest that humanized mice might prove useful in modeling infection. The development of humanized mouse models of S. aureus infection will allow us to assess the contribution of several human-specific virulence factors, in addition to exploring components of the human immune system in protection against S. aureus infection. Their use is discussed in light of several recently reported studies.

THE ANTIBACTERIAL ACTIVITY OF WATER APPLE LEAVES ACTIVE COMPOUND (Syzygium zeylanicum AGAINST Escherichia coli AND Staphylococcus aureus

Directory of Open Access Journals (Sweden)

- Hamidah

2017-07-01

Full Text Available Escherichia coli is one of the bacteria that cause infections in the human digestive tract such as diarrhea, while Staphylococcus aureus is one of the bacteria that cause infections in the skin injury such as boils and pimples. This study used Syzygium zeylanicum leaves because it has potential as a antibacterial because it contains active compounds. This study aimed was determine the antibacterial activity of the fraction and the active compound in Syzygium zeylanicum leaves against Escherichia coli and Staphylococcus aureus. Research conducted on November 2015 to January 2016. The method used in this research were extraction by maceration, fractionation by liquid fractionation, antibacterial activity test, and determination of minimum inhibitory concentration with the diffusion method and isolation of active compounds by column chromatography method. The bacteria used in this test are Escherichia coli and Staphylococcus aureus. Data are presented in tabular form based on the average value of the inhibition diameter and deviation standard. The results of this research showed the water methanol active fraction against the bacteria that used in this test. The methanol water fraction had obtained one antibacterial compound in bottle 1,3,5 which shows the value of tannin Rf 0,416. The minimum inhibitory concentration of water methanol of water apple leaves is 1000 µg/mL for Escherichia coli and 500 µg/mL for  Staphylococcus aureus. The minimum  inhibitory concentration of the active  compound  to  Escherichia  coli  and  Staphylococcus  aureus  in  500  µg/mL.  The fraction and the active compound of water apple leaves have an antibacterial activity with Escherichia coli and Staphylococcus aureus and the active compound is tannin.

Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells

NARCIS (Netherlands)

Sinha, B; Francois, P; Que, Y A; Hussain, M; Heilmann, C; Moreillon, P; Lew, D; Krause, K H; Peters, Georg; Herrmann, M

2000-01-01

Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell.

Epithelial Cell Gene Expression Induced by Intracellular Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Xianglu Li

2009-01-01

Full Text Available HEp-2 cell monolayers were cocultured with intracellular Staphylococcus aureus, and changes in gene expression were profiled using DNA microarrays. Intracellular S. aureus affected genes involved in cellular stress responses, signal transduction, inflammation, apoptosis, fibrosis, and cholesterol biosynthesis. Transcription of stress response and signal transduction-related genes including atf3, sgk, map2k1, map2k3, arhb, and arhe was increased. In addition, elevated transcription of proinflammatory genes was observed for tnfa, il1b, il6, il8, cxcl1, ccl20, cox2, and pai1. Genes involved in proapoptosis and fibrosis were also affected at transcriptional level by intracellular S. aureus. Notably, intracellular S. aureus induced strong transcriptional down-regulation of several cholesterol biosynthesis genes. These results suggest that epithelial cells respond to intracellular S. aureus by inducing genes affecting immunity and in repairing damage caused by the organism, and are consistent with the possibility that the organism exploits an intracellular environment to subvert host immunity and promote colonization.

Myricetin protects Galleria mellonella against Staphylococcus aureus infection and inhibits multiple virulence factors

DEFF Research Database (Denmark)

Nogueira-Silva, L; Da Hora, G. C.A.; Soares, Goncalo Teofilo Afonso Pinheiro

2017-01-01

Staphylococcus aureus is an opportunistic pathogen related to a variety of life-threatening infections but for which antimicrobial resistance is liming the treatment options. We report here that myricetin, but not its glycosylated form, can remarkably decrease the production of several S. aureus ...... in the Galleria mellonella model. The present findings reveal the potential of Myr as an alternative multi-target antivirulence candidate to control S. aureus pathogenicity....

Community-Associated Methicillin-Resistant Staphylococcus aureus Case Studies

Science.gov (United States)

Sowash, Madeleine G.; Uhlemann, Anne-Catrin

2014-01-01

Over the past decade, the emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has changed the landscape of S. aureus infections around the globe. Initially recognized for its ability to cause disease in young and healthy individuals without healthcare exposures as well as for its distinct genotype and phenotype, this original description no longer fully encompasses the diversity of CA-MRSA as it continues to expand its niche. Using four case studies, we highlight a wide range of the clinical presentations and challenges of CA-MRSA. Based on these cases we further explore the globally polygenetic background of CA-MRSA with a special emphasis on generally less characterized populations. PMID:24085688

Staphylococcus aureus in Some Brazilian Dairy Industries: Changes of Contamination and Diversity

DEFF Research Database (Denmark)

Dittmann, Karen Kiesbye; Chaul, Luiza T.; Lee, Sarah H. I.

2017-01-01

Staphylococcus aureus, a major food-poisoning pathogen, is a common contaminant in dairy industries worldwide, including in Brazil. We determined the occurrence of S. aureus in five dairies in Brazil over 8 months. Of 421 samples, 31 (7.4%) were positive for S. aureus and prevalence varied from 0.......8% of strains being sensitive to all antibiotic classes and no Methicillin-resistant S. aureus (MRSA) strains were found. The enterotoxin-encoding genes involved in food-poisoning, e.g., sea, sed, see, and seg were targeted by PCR. The two toxin-encoding genes, sed and see, were not detected. Only three strains...... contamination....

Substituted dihydronaphthalenes as efflux pump inhibitors of Staphylococcus aureus

DEFF Research Database (Denmark)

Thota, Niranjan; Reddy, Mallepally V; Kumar, Ashwani

2010-01-01

A new series of 3-(substituted-3,4-dihydronaphthyl)-2-propenoic acid amides has been prepared through convergent synthetic strategies and tested in combination with ciprofloxacin against NorA overexpressing Staphylococcus aureus 1199B as test strain for potentiating of the drug activity. Out of 24...... compounds evaluated, 12 compounds potentiated the activity of ciprofloxacin and resulted in 2-16 fold reduction in the MIC (4-0.5 microg/mL) of the drug. The failure of these efflux pump inhibitors (EPIs) to potentiate the activity of ciprofloxacin when tested against NorA knock out S. aureus SA-K1758...

Methicillin-resistant Staphylococcus aureus: a controversial food-borne pathogen.

Science.gov (United States)

Sergelidis, D; Angelidis, A S

2017-06-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of severe healthcare-associated (HA) infections. Although during the last decade the incidence of HA invasive infections has dropped, the incidence of community-associated MRSA (CA-MRSA) infections has risen among the general population. Moreover, CA-MRSA, livestock-associated MRSA (LA-MRSA) and HA-MRSA (HA-MRSA) can be found in foods intended for human consumption. Several studies from different geographical areas have reported the presence of enterotoxin genes in several MRSA food isolates. Molecular typing studies have revealed genetic relatedness of these enterotoxigenic isolates with isolates incriminated in human infections. The contamination sources for foods, especially animal-origin foods, may be livestock as well as humans involved in animal husbandry and food-processing. Under favourable environmental conditions for growth and enterotoxin production, enterotoxigenic S. aureus isolates present in foods can cause staphylococcal food poisoning (SFP), irrespective of the contamination origin. Owing to the typically moderate clinical manifestations of SFP, the S. aureus strains responsible for SFP (cases or outbreaks) are frequently either not identified or not further characterized. Antimicrobial susceptibility testing is rarely performed, because administration of antimicrobial therapy is not required in the vast majority of cases. Staphylococcal food poisoning is the result of consumption of foods with preformed enterotoxins. Hence, similar to methicillin-sensitive enterotoxigenic S. aureus, enterotoxigenic MRSA can also act as food-borne pathogens upon favourable conditions for growth and enterotoxin production. The severity of the intoxication is not related to the antimicrobial resistance profile of the causative S. aureus strain and therefore MRSA food-borne outbreaks are not expected to be more severe. This review evaluates the potential of methicillin-resistant Staphylococcus

Mild Staphylococcus aureus Skin Infection Improves the Course of Subsequent Endogenous S. aureus Bacteremia in Mice.

Directory of Open Access Journals (Sweden)

Sanne van den Berg

Full Text Available Staphylococcus aureus carriers with S. aureus bacteremia may have a reduced mortality risk compared to non-carriers. A role for the immune system is suggested. Here, we study in mice the effect of mild S. aureus skin infection prior to endogenous or exogenous S. aureus bacteremia, and evaluate protection in relation to anti-staphylococcal antibody levels. Skin infections once or twice by a clinical S. aureus isolate (isolate P or S. aureus strain 8325-4 were induced in mice free of S. aureus and anti-staphylococcal antibodies. Five weeks later, immunoglobulin G (IgG levels in blood against 25 S. aureus antigens were determined, and LD50 or LD100 bacteremia caused by S. aureus isolate P was induced. S. aureus skin infections led to elevated levels of anti-staphylococcal IgG in blood. One skin infection improved the course of subsequent severe endogenous bacteremia only. A second skin infection further improved animal survival rate, which was associated with increased pre-bacteremia IgG levels against Efb, IsaA, LukD, LukE, Nuc, PrsA and WTA. In conclusion, S. aureus isolate P skin infection in mice reduces the severity of subsequent endogenous S. aureus bacteremia only. Although cellular immune effects cannot be rules out, anti-staphylococcal IgG against specified antigens may contribute to this effect.

Rapid control of a methicillin resistant Staphylococcus aureus (MRSA) outbreak in a medical surgical intensive care unit (ICU).

Science.gov (United States)

Khan, Anjum; Lampitoc, Marianita; Salaripour, Maryam; McKernan, Patricia; Devlin, Roslyn; Muller, Matthew P

2009-01-01

Outbreaks of methicillin resistant Staphylococcus aureus in the intensive care unit setting can be prolonged and difficult to control. This report describes the rapid control of an outbreak of methicillin resistant Staphylococcus aureus in a 24-bed open-concept medical surgical intensive care unit with a baseline methicillin resistant Staphylococcus aureus acquisition rate of 1.5 cases per 1000 patient days. This institution's infection control policy mandates an outbreak investigation if two cases of hospital-acquired methicillin resistant Staphylococcus aureus colonization or infection are identified in an intensive care unit within a four-week period. In July 2007, methicillin resistant Staphylococcus aureus was identified in the sputum of two patients within a one-week period. Screening of all patients in the intensive care unit identified one additional case and a fourth case was identified from a clinical specimen before control measures were implemented. Initial control measures included healthcare worker education, enhanced surveillance, patient cohorting, and enhanced environmental cleaning. Despite these measures, three more cases occurred. All patients were then placed in contact isolation, healthcare workers were screened, and the nursing staff was cohorted. After two weeks without a case, two additional cases were identified. Decolonization of all positive patients was initiated. No further cases occurred over a five-week period and the outbreak was declared over. The outbreak resulted in nine cases of methicillin resistant Staphylococcus aureus colonization (n = 8) or infection (n = 1) over an 11-week period. Only one of 175 healthcare workers was colonized and it was not the outbreak strain. Early detection and the stepwise addition of infection control measures resulted in the rapid control of an outbreak of methicillin resistant Staphylococcus aureus in a medical surgical intensive care unit without unit closure. A low threshold of suspicion and

Toxic shock syndrome due to community-acquired methicillin-resistant Staphylococcus aureus infection: Two case reports and a literature review in Japan.

Science.gov (United States)

Sada, Ryuichi; Fukuda, Saori; Ishimaru, Hiroyasu

2017-01-01

Community-acquired methicillin-resistant Staphylococcus aureus has been spreading worldwide, including in Japan. However, few cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus have been reported in Japan. We report 2 cases, in middle-aged women, of toxic shock syndrome due to Community-acquired methicillin-resistant Staphylococcus aureus via a vaginal portal of entry. The first patient had used a tampon and the second patient had vaginitis due to a cleft narrowing associated with vulvar lichen sclerosus. Both patients were admitted to our hospital with septic shock and severe acute kidney injury and subsequently recovered with appropriate antibiotic treatment. In our review of the literature, 8 cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus were reported in Japan. In these 8 cases, the main portals of entry were the skin and respiratory tract; however, the portal of entry of Community-acquired methicillin-resistant Staphylococcus aureus from a vaginal lesion has not been reported in Japan previously.

Bovine origin Staphylococcus aureus: A new zoonotic agent?

Science.gov (United States)

Rao, Relangi Tulasi; Jayakumar, Kannan; Kumar, Pavitra

2017-10-01

The study aimed to assess the nature of animal origin Staphylococcus aureus strains. The study has zoonotic importance and aimed to compare virulence between two different hosts, i.e., bovine and ovine origin. Conventional polymerase chain reaction-based methods used for the characterization of S. aureus strains and chick embryo model employed for the assessment of virulence capacity of strains. All statistical tests carried on R program, version 3.0.4. After initial screening and molecular characterization of the prevalence of S. aureus found to be 42.62% in bovine origin samples and 28.35% among ovine origin samples. Meanwhile, the methicillin-resistant S. aureus prevalence is found to be meager in both the hosts. Among the samples, only 6.8% isolates tested positive for methicillin resistance. The biofilm formation quantified and the variation compared among the host. A Welch two-sample t -test found to be statistically significant, t=2.3179, df=28.103, and p=0.02795. Chicken embryo model found effective to test the pathogenicity of the strains. The study helped to conclude healthy bovines can act as S. aureus reservoirs. Bovine origin S. aureus strains are more virulent than ovine origin strains. Bovine origin strains have high probability to become zoonotic pathogen. Further, gene knock out studies may be conducted to conclude zoonocity of the bovine origin strains.

A Novel ESAT-6 Secretion System-Secreted Protein EsxX of Community-Associated Staphylococcus aureus Lineage ST398 Contributes to Immune Evasion and Virulence

Directory of Open Access Journals (Sweden)

Yingxin Dai

2017-05-01

Full Text Available The ESAT-6 secretion system (ESS has been reported to contribute to the virulence and pathogenicity of several Staphylococcus aureus strains such as USA300 and Newman. However, the role of the ESS in community-associated S. aureus (CA-SA lineage ST398 in China is not well understood. By comparing the ess locus of ST398 with the published S. aureus sequence in the NCBI database, we found one gene in the ess locus encoding a novel WXG superfamily protein that is highly conserved only in ST398. LC-MS/MS and Western blot analysis revealed that this protein is a novel secreted protein controlled by the ST398 ESS, and we named the protein EsxX. Although EsxX was not under the control of the accessory gene regulator like many other virulence factors and had no influence on several phenotypes of ST398, such as growth, hemolysis, and biofilm formation, it showed important impacts on immune evasion and virulence in ST398. An esxX deletion mutant led to significantly reduced resistance to neutrophil killing and decreased virulence in murine skin and blood infection models, indicating its essential contribution to the evasion of innate host defense and virulence to support the pathogenesis of ST398 infections. The function of this novel secreted protein EsxX might help us better understand the role of the ESS in the virulence and epidemic success of the CA-SA lineage ST398.

A Novel ESAT-6 Secretion System-Secreted Protein EsxX of Community-Associated Staphylococcus aureus Lineage ST398 Contributes to Immune Evasion and Virulence.

Science.gov (United States)

Dai, Yingxin; Wang, Yanan; Liu, Qian; Gao, Qianqian; Lu, Huiying; Meng, Hongwei; Qin, Juanxiu; Hu, Mo; Li, Min

2017-01-01

The ESAT-6 secretion system (ESS) has been reported to contribute to the virulence and pathogenicity of several Staphylococcus aureus strains such as USA300 and Newman. However, the role of the ESS in community-associated S. aureus (CA-SA) lineage ST398 in China is not well understood. By comparing the ess locus of ST398 with the published S. aureus sequence in the NCBI database, we found one gene in the ess locus encoding a novel WXG superfamily protein that is highly conserved only in ST398. LC-MS/MS and Western blot analysis revealed that this protein is a novel secreted protein controlled by the ST398 ESS, and we named the protein EsxX. Although EsxX was not under the control of the accessory gene regulator like many other virulence factors and had no influence on several phenotypes of ST398, such as growth, hemolysis, and biofilm formation, it showed important impacts on immune evasion and virulence in ST398. An esxX deletion mutant led to significantly reduced resistance to neutrophil killing and decreased virulence in murine skin and blood infection models, indicating its essential contribution to the evasion of innate host defense and virulence to support the pathogenesis of ST398 infections. The function of this novel secreted protein EsxX might help us better understand the role of the ESS in the virulence and epidemic success of the CA-SA lineage ST398.

Characterization and lytic activity of methicillin-resistant Staphylococcus aureus(MRSA phages isolated from NICU

Directory of Open Access Journals (Sweden)

Golnar Rahimzadeh

2016-06-01

Full Text Available Background Methicillin-resistant Staphylococcus aureus (MRSA is a well-known pathogen that causes serious diseases in humans. As part of the efforts to control this pathogen, an isolated bacteriophage, Siphoviridae, which specifically targets Methicillin-resistant Staphylococcus aureus (MRSA, was characterized. Aims The objective of this study was to characterize of a virulent bacteriophage (Siphoviridae isolated from a NICU bathroom sink. Methods The MRSA strain was isolated from patient blood. The isolated strain was confirmed as MRSA using conventional methods. Phages were isolated from a NICU bathroom sink and activity was lytic as determined by spot test. Titer phage lysate was measured by the Double Layer Agar (DLA technique. The morphology was found with electron microscopy. The single-step growth curve was plotted. Results Electron microscopy showed the phage as a member of the family Siphoviridae, serogroup A and F. The isolated phage was capable of lytic activity against methicillin-resistant Staphylococcus aureus (MRSA strain as shown by spot test. By DLA, the titre of the phages was determined to be 10×108PFU/ml. The single-step growth curve showed that the latent period of the isolated bacteriophage was 30 min and the total number of viable progeny per infected host, burst size, was 2600 PFU/infected host. Conclusion In this study, two phages were isolated and characterized from a NICU bathroom sink, from the Siphoviridae family, which specifically targetsmethicillin-resistant Staphylococcus aureus (MRSA.

Duplex Identification of Staphylococcus aureus by Aptamer and Gold Nanoparticles.

Science.gov (United States)

Chang, Tianjun; Wang, Libo; Zhao, Kexu; Ge, Yu; He, Meng; Li, Gang

2016-06-01

Staphylococcus aureus is the top common pathogen causing infections and food poisoning. Identification of S. aureus is crucial for the disease diagnosis and regulation of food hygiene. Herein, we report an aptamer-AuNPs based method for duplex identification of S. aureus. Using AuNPs as an indicator, SA23, an aptamer against S. aureus, can well identify its target from Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa. Furthermore, we find citrate-coated AuNPs can strongly bind to S. aureus, but not bind to Salmonella enterica and Proteus mirabilis, which leads to different color changes in salt solution. This colorimetric response is capable of distinguishing S. aureus from S. enteritidis and P. mirabilis. Thus, using the aptasensor and AuNPs together, S. aureus can be accurately identified from the common pathogens. This duplex identification system is a promising platform for simple visual identification of S. aureus. Additionally, in the aptasensing process, bacteria are incubated with aptamers and then be removed before the aptamers adding to AuNPs, which may avoid the interactions between bacteria and AuNPs. This strategy can be potentially applied in principle to detect other cells by AuNPs-based aptasensors.

Aspartate inhibits Staphylococcus aureus biofilm formation.

Science.gov (United States)

Yang, Hang; Wang, Mengyue; Yu, Junping; Wei, Hongping

2015-04-01

Biofilm formation renders Staphylococcus aureus highly resistant to conventional antibiotics and host defenses. Four D-amino acids (D-Leu, D-Met, D-Trp and D-Tyr) have been reported to be able to inhibit biofilm formation and disassemble established S. aureus biofilms. We report here for the first time that both D- and L-isoforms of aspartate (Asp) inhibited S. aureus biofilm formation on tissue culture plates. Similar biofilm inhibition effects were also observed against other staphylococcal strains, including S. saprophyticus, S. equorum, S. chromogenes and S. haemolyticus. It was found that Asp at high concentrations (>10 mM) inhibited the growth of planktonic N315 cells, but at subinhibitory concentrations decreased the cellular metabolic activity without influencing cell growth. The decreased cellular metabolic activity might be the reason for the production of less protein and DNA in the matrix of the biofilms formed in the presence of Asp. However, varied inhibition efficacies of Asp were observed for biofilms formed by clinical staphylococcal isolates. There might be mechanisms other than decreasing the metabolic activity, e.g. the biofilm phenotypes, affecting biofilm formation in the presence of Asp. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Brain infection following experimental Staphylococcus aureus sepsis in pigs

DEFF Research Database (Denmark)

Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg

2010-01-01

Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... of spontaneous porcine pyemia including endocarditis and associated brain lesions. We present a porcine model of haematogenous S. aureus induced brain infection. Materials and Methods: Twelve pigs received an intravenous injection of S. aureus of 108 CFU/kg body weight once at 0h or twice at 0h and 12h. Four...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

Estudo Comparativo da Ação Bactericida do Mel sobre Staphylococcus aureus/Comparative Study of the Honey Antimicrobial Activity on Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Othon José Ribeiro Pereira

2015-06-01

Full Text Available Objetivo: Analisar, a partir da metodologia microbiológica, a ação bactericida dos diferentes tipos de mel, segundo sua florada de origem. Materiais e Métodos: foram adquiridas três amostras de cada tipo de mel, segundo sua florada de origem, sendo eles: Flores de Café, Cipó-Uva, Assa-Peixe, Limão, Laranjeira, Eucalipto e Silvestre. Os discos foram preparados sendo embebidos em mel, e mantidos em estufa para secagem. Estes foram então colocados em contato com placa de Petri, previamente preparadas com Ágar Nutriente, contendo Staphylococcus aureus, e colocados em estufa para secagem. Após 24 horas, observou-se se houve inibição da cepa bacteriana, formando halo ao redor do disco. Resultado: Notou-se, na leitura das 21 placas, que nao houve diferença significativa nos halos de inibição formados pelos diferentes tipos de mel testados. Conclusão: Pelo estudo realizado, pode-se concluir que não há diferença na ação bactericida, sobre cepa de Staphylococcus aureus, entre os diferentes tipos de mel segundo as floradas de origem testadas. Objective: To analyze, according to microbiological methodology, the bactericidal action of different ypes on honey, according to the flowering origin. Materials and Methods: three samples of each types of honey were acquired, according to the flowering of origin, namely: Coffee Flowers, Vine-Grape, Assa-Peixe, Lemon, Orange, Eucalyptus and Sylvan. The disks were prepared by being soaked in honey, and were kept in a kilnfor drying. These were then placed in contact with Petri dish, previously prepared with Nutrient Agar, containing Staphylococcus aureus, and placed in kiln for drying. After 24 hours, it was observed if there was inhibition of bacterial strain, by forming a halo around the disk. Results: It was noted, in the reading of the 21 plates, no significant difference in the inhibition halos formed by different types of honey tested. Conclusion:By the study, it can be concluded that there

eap Gene as novel target for specific identification of Staphylococcus aureus.

Science.gov (United States)

Hussain, Muzaffar; von Eiff, Christof; Sinha, Bhanu; Joost, Insa; Herrmann, Mathias; Peters, Georg; Becker, Karsten

2008-02-01

The cell surface-associated extracellular adherence protein (Eap) mediates adherence of Staphylococcus aureus to host extracellular matrix components and inhibits inflammation, wound healing, and angiogenesis. A well-characterized collection of S. aureus and non-S. aureus staphylococcal isolates (n = 813) was tested for the presence of the Eap-encoding gene (eap) by PCR to investigate the use of the eap gene as a specific diagnostic tool for identification of S. aureus. Whereas all 597 S. aureus isolates were eap positive, this gene was not detectable in 216 non-S. aureus staphylococcal isolates comprising 47 different species and subspecies of coagulase-negative staphylococci and non-S. aureus coagulase-positive or coagulase-variable staphylococci. Furthermore, non-S. aureus isolates did not express Eap homologs, as verified on the transcriptional and protein levels. Based on these data, the sensitivity and specificity of the newly developed PCR targeting the eap gene were both 100%. Thus, the unique occurrence of Eap in S. aureus offers a promising tool particularly suitable for molecular diagnostics of this pathogen.

Evaluation of Coagulase-Positive Staphylococcus Aureus Contamination in Lighvan Cheese on Retail Stores

Directory of Open Access Journals (Sweden)

Ali Salehi

2014-03-01

Full Text Available Background: Staphylococcus aureus is a Gram-positive, non-sporulated, lack of capsule, immovable, aerobic and anaerobic and able to tolerate high levels of salt (up to 15 percent. Therefore, foods containing salt provides an ideal environment for bacterial growth. It is also one of the most important bacterial born of spoilable food products, especially in dairy products. Lighvan traditional cheese is consumed in many regions of Iran, especially consumption of these cheeses is very high in Tehran which in the manufacture of such cheeses, the unpasteurized and raw milk is used and the sanitary conditions during processing and subsequent storage are low. So, considering the importance of this issue in the release of poisoning, the coagulase-positive Staphylococcus aureus contamination in Lighvan cheese on Retail Stores was evaluated. Materials and Methods: In order to perform this study, 22 samples of traditional Lighvan cheese were collected randomly from Tehran stores and according to Iran national standards and by using of bird-parker, Cook Meat cultures and coagulase test were evaluated. Results: Total of 22 samples, 14 samples (63/6% were contaminated by S. aureus over standard and 5 (22/7% were contaminated with Staphylococcus aureus coagulase positive. Conclusion: This study demonstrated that sanitary conditions should be observed during the production and Use of pasteurized milk in cheese production.

High genetic diversity among community-associated Staphylococcus aureus in Europe

DEFF Research Database (Denmark)

Rolo, Joana; Miragaia, Maria; Turlej-Rogacka, Agata

2012-01-01

Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S...

Staphylococcus aureus Transcriptome Architecture : From Laboratory to Infection-Mimicking Conditions

NARCIS (Netherlands)

Maeder, Ulrike; Nicolas, Pierre; Depke, Maren; Pane-Farre, Jan; Debarbouille, Michel; van der Kooi-Pol, Magdalena M.; Guerin, Cyprien; Derozier, Sandra; Hiron, Aurelia; Jarmer, Hanne; Leduc, Aurelie; Michalik, Stephan; Reilman, Ewoud; Schaffer, Marc; Schmidt, Frank; Bessieres, Philippe; Noirot, Philippe; Hecker, Michael; Msadek, Tarek; Voelker, Uwe; van Dijl, Jan Maarten

Staphylococcus aureus is a major pathogen that colonizes about 20% of the human population. Intriguingly, this Gram-positive bacterium can survive and thrive under a wide range of different conditions, both inside and outside the human body. Here, we investigated the transcriptional adaptation of S.

In vitro mecA gene transfer among Staphylococcus aureus in ...

African Journals Online (AJOL)

... Staphylococcus aureus, Malaysian clinical isolates, to methicillin-sensitive one. PCR-based method was used in combination with the selective antibiotic screening method to study the transfer of resistance among clinical isolates carrying different genetic markers. After performing the mixed liquid culture experiments, two ...

Multiple drug resistance Staphylococcus aureus isolated in foods of ...

African Journals Online (AJOL)

Background: StaphylococcuS. aureus is the most important agent, which is known to cause a wide range of diseases in both human and animals. Extended use and misuse of antibiotics in agriculture, stock farming and in the treatment of human diseases, has contributed to the rapid increase of the number of bacteria that ...

Protective effects of tenuigenin on Staphylococcus aureus-induced pneumonia in mice.

Science.gov (United States)

Yu, Bin; Qiao, Jiutao; Shen, Yongbin; Li, Lianyong

2017-09-01

Pneumonia is the leading cause of death in infants and young children. Staphylococcus aureus (S.aureus) is one of the most important bacteria that leads to pneumonia. Tenuigenin (TGN), a major active component isolated from the root of the Chinese herb Polygala tenuifolia, has been known to have anti-inflammatory effect. In this study, we aimed to investigate the protective effects of TGN on S.aureus-induced pneumonia in mice. The results showed that TGN significantly attenuated S.aureus-induced lung histopathological changes. TGN also inhibited lung wet/dry (W/D) ratio, and inflammatory cytokines TNF-α and IL-1β production. Furthermore, S.aureus-induced NF-κB activation was significantly inhibited by the treatment of TGN. In conclusion, the results of this study showed that TGN protected against S.aureus-induced pneumonia by inhibiting NF-κB activation. TGN might be a potential agent in the treatment of pneumonia induced by S.aureus. Copyright © 2017 Elsevier Ltd. All rights reserved.

Survey and properties of Staphylococcus aureus isolated from Japanese-style desserts.

Science.gov (United States)

Shimamura, Yuko; Kidokoro, Shiho; Murata, Masatsune

2006-07-01

We surveyed the contamination of 315 Japanese- and western-style desserts and 247 human hands by Staphylococcus aureus and other staphylococcal bacteria. The most frequently isolated staphylococcal bacterium was S. warneri, followed by S. aureus. Only 1.9% of western-style desserts were contaminated by S. aureus strains, while 19.4% and 13.0% of Japanese-style desserts and human hands respectively were contaminated. Ninety-four isolates of S. aureus were characterized as to their biological properties and enterotoxigenicity. Although staphylococcal enterotoxins (SEs) were detected by enzyme-linked immunosorbent assay in the cultured broth of all S. aureus isolates, the reversed passive latex agglutination method and the polymerase chain reaction showed only 39 (41.5%) and 40 (42.6%) samples respectively as SE-positive. The predominant type of SE was SEB (67.5%), and eight strains produced SEA. None of the S. aureus strains had penicillin-binding protein 2', showing that methicillin-resistant S. aureus was not present in the samples.

Expression of Virulence Factors by Staphylococcus aureus Grown in Serum▿†

OpenAIRE

Oogai, Yuichi; Matsuo, Miki; Hashimoto, Masahito; Kato, Fuminori; Sugai, Motoyuki; Komatsuzawa, Hitoshi

2011-01-01

Staphylococcus aureus produces many virulence factors, including toxins, immune-modulatory factors, and exoenzymes. Previous studies involving the analysis of virulence expression were mainly performed by in vitro experiments using bacterial medium. However, when S. aureus infects a host, the bacterial growth conditions are quite different from those in a medium, which may be related to the different expression of virulence factors in the host. In this study, we investigated the expression of...

Development of An Impedimetric Aptasensor for the Detection of Staphylococcus aureus

OpenAIRE

Reich, Peggy; Stoltenburg, Regina; Strehlitz, Beate; Frense, Dieter; Beckmann, Dieter

2017-01-01

In combination with electrochemical impedance spectroscopy, aptamer-based biosensors are a powerful tool for fast analytical devices. Herein, we present an impedimetric aptasensor for the detection of the human pathogen Staphylococcus aureus. The used aptamer targets protein A, a surface bound virulence factor of S. aureus. The thiol-modified protein A-binding aptamer was co-immobilized with 6-mercapto-1-hexanol onto gold electrodes by self-assembly. Optimization of the ratio of aptamer to 6-...

Individual predisposition to Staphylococcus aureus colonization in pigs based on quantification, carriage dynamics and serological profiles

DEFF Research Database (Denmark)

Gongora, Carmen Espinosa; Dahl, Jan; Elvstrøm, Anders

2015-01-01

Previous research on Staphylococcus aureus in pigs focused on livestock-associated methicillin-resistant S. aureus (MRSA) and had qualitative cross-sectional design. This study aimed to elucidate frequency, load and stability of S. aureus nasal carriage in pigs over time and investigated possible...

Prevalence of chlorhexidine-resistant methicillin-resistant Staphylococcus aureus following prolonged exposure.

Science.gov (United States)

Schlett, Carey D; Millar, Eugene V; Crawford, Katrina B; Cui, Tianyuan; Lanier, Jeffrey B; Tribble, David R; Ellis, Michael W

2014-08-01

Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant Staphylococcus aureus (MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which 10,030 soldiers were issued chlorhexidine for body washing. We obtained epidemiological data on study participants and performed molecular analysis of MRSA isolates, including PCR assays for determinants of chlorhexidine resistance and high-level mupirocin resistance and pulsed-field gel electrophoresis (PFGE). During the study period, May 2010 to January 2012, we identified 720 MRSA isolates, of which 615 (85.4%) were available for molecular analysis, i.e., 341 clinical and 274 colonizing isolates. Overall, only 10 (1.6%) of 615 isolates were chlorhexidine resistant, including three from the chlorhexidine group and seven from nonchlorhexidine groups (P > 0.99). Five (1.5%) of the 341 clinical isolates and five (1.8%) of the 274 colonizing isolates harbored chlorhexidine resistance genes, and four (40%) of the 10 possessed genetic determinants for mupirocin resistance. All chlorhexidine-resistant isolates were USA300. The overall prevalence of chlorhexidine resistance in MRSA isolates obtained from our study participants was low. We found no association between extended chlorhexidine use and the prevalence of chlorhexidine-resistant MRSA isolates; however, continued surveillance is warranted, as this agent continues to be utilized for infection control and prevention efforts. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Marinopyrrole Derivatives as Potential Antibiotic Agents against Methicillin-Resistant Staphylococcus aureus (II

Directory of Open Access Journals (Sweden)

Rongshi Li

2013-08-01

Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA continues to be a major problem, causing severe and intractable infections worldwide. MRSA is resistant to all beta-lactam antibiotics, and alternative treatments are limited. A very limited number of new antibiotics have been discovered over the last half-century, novel agents for the treatment of MRSA infections are urgently needed. Marinopyrrole A was reported to show antibiotic activity against MRSA in 2008. After we reported the first total synthesis of (±-marinopyrrole A, we designed and synthesized a series of marinopyrrole derivatives. Our structure activity relationship (SAR studies of these novel derivatives against a panel of Gram-positive pathogens in antibacterial assays have revealed that a para-trifluoromethyl analog (33 of marinopyrrole A is ≥63-, 8-, and 4-fold more potent than vancomycin against methicillin-resistant Staphylococcus epidermidis (MRSE, methicillin-susceptible Staphylococcus aureus (MSSA and MRSA, respectively. The results provide valuable information in the search for new-generation antibiotics.

A natural human monoclonal antibody targeting Staphylococcus Protein A protects against Staphylococcus aureus bacteremia

Science.gov (United States)

Varshney, Avanish K.; Sunley, Kevin M.; Bowling, Rodney A.; Kwan, Tzu-Yu; Mays, Heather R.; Rambhadran, Anu; Zhang, Yanfeng; Martin, Rebecca L.; Cavalier, Michael C.; Simard, John

2018-01-01

Staphylococcus aureus can cause devastating and life-threatening infections. With the increase in multidrug resistant strains, novel therapies are needed. Limited success with active and passive immunization strategies have been attributed to S. aureus immune evasion. Here, we report on a monoclonal antibody, 514G3, that circumvents a key S. aureus evasion mechanism by targeting the cell wall moiety Protein A (SpA). SpA tightly binds most subclasses of immunoglobulins via their Fc region, neutralizing effector function. The organism can thus shield itself with a protective coat of serum antibodies and render humoral immunity ineffective. The present antibody reactivity was derived from an individual with natural anti-SpA antibody titers. The monoclonal antibody is of an IgG3 subclass, which differs critically from other immunoglobulin subclasses since its Fc is not bound by SpA. Moreover, it targets a unique epitope on SpA that allows it to bind in the presence of serum antibodies. Consequently, the antibody opsonizes S. aureus and maintains effector function to enable natural immune mediated clearance. The data presented here provide evidence that 514G3 antibody is able to successfully rescue mice from S. aureus mediated bacteremia. PMID:29364906

Determination of the Presence of crpgenes in Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus delbrueckii and Corynebacterium veraSuş

OpenAIRE

BELDÜZ, Ali Osman; DEMİRBAĞ, Zihni; DÜLGER, Sabriye

2014-01-01

Polymerase chain reaction (PCR) was employed to detect the presence of cyclic AMP receptor protein (CPR) in a number of diverse organisms. In PCR, two primers specific to the crp gene of Escherichia coli were used. Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus delbrueckii and Corynebacterium veraSuş all showed the same size of PCR frağments (708 bp) and same restriction frağment length polymorphizm (RFLP).

Linear peptidomimetics as potent antagonists of Staphylococcus aureus agr quorum sensing

DEFF Research Database (Denmark)

Karathanasi, Georgia; Bojer, Martin Saxtorph; Baldry, Mara

2018-01-01

Staphylococcus aureus is an important pathogen causing infections in humans and animals. Increasing problems with antimicrobial resistance has prompted the development of alternative treatment strategies, including antivirulence approaches targeting virulence regulation such as the agr quorum...

Enzymatic degradation of in vitro Staphylococcus aureus biofilms supplemented with human plasma

Directory of Open Access Journals (Sweden)

Watters CM

2016-04-01

Full Text Available Chase M Watters,1,2 Tarea Burton,1 Dickson K Kirui,1 Nancy J Millenbaugh1 1Maxillofacial Injury and Disease Department, Naval Medical Research Unit San Antonio, Joint Base San Antonio-Fort Sam Houston, TX, USA; 2Wound Infections Department, Naval Medical Research Center, Silver Spring, MD, USA Abstract: Enzymatic debridement is a therapeutic strategy used clinically to remove necrotic tissue from wounds. Some of the enzymes utilized for debridement have been tested against bacterial pathogens, but the effectiveness of these agents in dispersing clinically relevant biofilms has not been fully characterized. Here, we developed an in vitro Staphylococcus aureus biofilm model that mimics wound-like conditions and employed this model to investigate the antibiofilm activity of four enzymatic compounds. Human plasma at concentrations of 0%–50% was supplemented into growth media and used to evaluate biofilm biomass accumulation over 24 hours and 48 hours in one methicillin-sensitive and five methicillin-resistant strains of S. aureus. Supplementation of media with 10% human plasma resulted in the most robust biofilms in all six strains. The enzymes α-amylase, bromelain, lysostaphin, and papain were then tested against S. aureus biofilms cultured in 10% human plasma. Quantification of biofilms after 2 hours and 24 hours of treatment using the crystal violet assay revealed that lysostaphin decreased biomass by up to 76%, whereas a-amylase, bromelain, and papain reduced biomass by up to 97%, 98%, and 98%, respectively. Scanning electron microscopy confirmed that the dispersal agents detached the biofilm exopolysaccharide matrix and bacteria from the growth surface. Lysostaphin caused less visible dispersal of the biofilms, but unlike the other enzymes, induced morphological changes indicative of bacterial cell damage. Overall, our results indicate that use of enzymes may be an effective means of eradicating biofilms and a promising strategy to improve

Hospitalizations and Deaths Caused by Methicillin-Resistant Staphylococcus aureus, United States, 1999?2005

OpenAIRE

Klein, Eili; Smith, David L.; Laxminarayan, Ramanan

2007-01-01

Hospital-acquired infections with Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA) infections, are a major cause of illness and death and impose serious economic costs on patients and hospitals. However, the recent magnitude and trend of these infections have not been reported. We used national hospitalization and resistance data to estimate the annual number of hospitalizations and deaths associated with S. aureus and MRSA from 1999 through 2005. During this period, t...

Toxic shock syndrome due to community-acquired methicillin-resistant Staphylococcus aureus infection: Two case reports and a literature review in Japan

OpenAIRE

Sada, Ryuichi; Fukuda, Saori; Ishimaru, Hiroyasu

2017-01-01

Community-acquired methicillin-resistant Staphylococcus aureus has been spreading worldwide, including in Japan. However, few cases of toxic shock syndrome caused by Community-acquired methicillin-resistant Staphylococcus aureus have been reported in Japan. We report 2 cases, in middle-aged women, of toxic shock syndrome due to Community-acquired methicillin-resistant Staphylococcus aureus via a vaginal portal of entry. The first patient had used a tampon and the second patient had vaginitis ...

Comparison of four methods for rapid identification of Staphylococcus aureus directly from BACTEC 9240 blood culture system

Directory of Open Access Journals (Sweden)

N S Ozen

2011-01-01

Full Text Available Purpose: Differentiation of Staphylococcus aureus (S. aureus from coagulase-negative staphylococci is very important in blood stream infections. Identification of S. aureus and coagulase-negative staphylococci (CoNS from blood cultures takes generally 18-24 h after positive signaling on continuously monitored automated blood culture system. In this study, we evaluated the performance of tube coagulase test (TCT, slide agglutination test (Dry Spot Staphytect Plus, conventional polymerase chain reaction (PCR and LightCycler Staphylococcus MGrade kit directly from blood culture bottles to achieve rapid identification of S. aureus by using the BACTEC 9240 blood culture system. Materials and Methods: A total of 129 BACTEC 9240 bottles growing gram-positive cocci suggesting Staphylococci were tested directly from blood culture broths (BCBs with TCT, Dry Spot Staphytect Plus, conventional PCR and LightCycler Staphylococcus MGrade kit for rapid identification of S. aureus. Results: The sensitivities of the tests were 99, 68, 99 and 100%, respectively. Conclusion: Our results suggested that 2 h TCT was found to be simple and inexpensive method for the rapid identification of S. aureus directly from positive blood cultures.

Panton-valentine leukocidin enhances the severity of community-associated methicillin-resistant Staphylococcus aureus rabbit osteomyelitis.

Directory of Open Access Journals (Sweden)

Anne-Claude Crémieux

Full Text Available BACKGROUND: Extensive spread of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA in the United States, and the concomitant increase in severe invasive staphylococcal infections, including osteomyelitis, in healthy children, has led to renewed interest in Panton-Valentine leukocidin (PVL. However, the pathogenetic role of PVL in staphylococcal infections remains controversial, possibly because it depends on the site of infection. METHODOLOGY/PRINCIPAL FINDINGS: We compared the course of experimental rabbit osteomyelitis due to the PVL-positive CA-MRSA strain USA 300 (LAC and its PVL-negative isogenic derivative (LACDeltapvl, using a low and a high inoculum (8x10(5 and 4x10(8 CFU. With the low inoculum, bone infection was less frequent on day 7 (D7 and day 28 (D28 with LACDeltapvl than with LAC (respectively 12/19 and 18/19 animals, p = 0.042. With the high inoculum of both strains, all the animals were infected on D7 and the infection persisted on D28 in almost every case. However, tibial bacterial counts and the serum CRP concentration fell significantly between D7 and D28 with LACDeltapvl but not with LAC. Respectively 67% and 60% of LAC-infected rabbits had bone deformation and muscle/joint involvement on D7, compared to 0% and 7% of LACDeltapvl-infected rabbits (p = 0.001 and p = 0.005 respectively. Between D0 and D28, the anti-PVL antibody titer increased significantly only with the high inoculum of LAC. CONCLUSIONS/SIGNIFICANCE: PVL appears to play a role in the persistence and rapid local extension of rabbit osteomyelitis, in keeping with the greater severity of human bone infections due to PVL-positive S. aureus. The possible therapeutic implications of these findings are discussed.

Occurrence and distribution of Staphylococcus aureus lineages among zoo animals

DEFF Research Database (Denmark)

Gongora, Carmen Espinosa; Chrobak, Dorota; Moodley, Arshnee

2012-01-01

The current knowledge of the occurrence and diversity of Staphylococcus aureus in animals is largely biased in favour MRSA and domestic animals. In order to generate novel information on the ecology and population structure of this bacterial species in the animal kingdom, we investigated...... the occurrence and genotypic diversity of S. aureus in a range of animal species kept at the Copenhagen Zoo. We sampled 146 animals belonging to 25 mammalian species and 21 reptiles belonging to six species. A total of 59 S. aureus isolates were found in 10 of the 25 mammalian species tested. All isolates were...... MSSA belonging to fourteen spa types, including three novel spa types. MLST revealed the occurrence of seven STs. The study of the ecology of commensal S. aureus in captive wild animals revealed that ST133 has a broader host range than previously thought....

Incidence of staphylococcus aureus in locally produced fresh milk ...

African Journals Online (AJOL)

This paper investigates the incidence of the bacterial organism Staphylococcus, aureus in locally produced fresh milk (nono). The fresh milk was obtained from the Damaturu main market, Yobe state of Nigeria. Petri dishes were washed and allowed to dry. They were then sterilized in hot air oven at 130°C for two hours and ...