Detection of Cryptosporidium parvum Oocysts on Fresh Produce Using DNA Aptamers.

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Asma Iqbal

Full Text Available There are currently no standard methods for the detection of Cryptosporidium spp., or other protozoan parasites, in foods, and existing methods are often inadequate, with low and variable recovery efficiencies. Food testing is difficult due to the low concentrations of parasites, the difficulty in eluting parasites from some foods, the lack of enrichment methods, and the presence of PCR inhibitors. The main objectives of the present study were to obtain DNA aptamers binding to the oocyst wall of C. parvum, and to use the aptamers to detect the presence of this parasite in foods. DNA aptamers were selected against C. parvum oocysts using SELEX (Systematic Evolution of Ligands by EXponential enrichment. Ten rounds of selection led to the discovery of 14 aptamer clones with high affinities for C. parvum oocysts. For detecting parasite-bound aptamers, a simple electrochemical sensor was employed, which used a gold nanoparticle-modified screen-printed carbon electrode. This aptasensor was fabricated by self-assembling a hybrid of a thiolated ssDNA primer and the anti- C. parvum aptamer. Square wave voltammetry was employed to quantitate C. parvum in the range of 150 to 800 oocysts, with a detection limit of approximately 100 oocysts. The high sensitivity and specificity of the developed aptasensor suggests that this novel method is very promising for the detection and identification of C. parvum oocysts on spiked fresh fruits, as compared to conventional methods such as microscopy and PCR.

Corynebacterium minutissimum vascular graft infection: case report and review of 281 cases of prosthetic device-related Corynebacterium infection.

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Reece, Rebecca M; Cunha, Cheston B; Rich, Josiah D

2014-09-01

Corynebacterium spp. have proven their pathogenic potential in causing infections, particularly in the setting of immunosuppression and prosthetic devices. We conducted a PubMed literature review of all cases of Corynebacterium prosthetic device infections published in the English language through December 2013. The majority of cases involved peritoneal dialysis and central venous catheters, but prosthetic joints and central nervous system shunts/drains were also involved. The management of these cases in terms of retention or removal of the device was not uniform; however, the overall mortality remained the same among both groups. All of these prosthetic device infections pose potential problems in management when the device cannot be removed safely for the patient, especially with the lack of data on the pathogenicity of Corynebacterium species. However with better identification of species and sensitivities, successful treatment is possible even with retention of the device.

Gamma irradiation of Cryptosporidium parvum oocysts affects intracelluar levels of the viral symbiont CPV

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Previous studies have shown a dose-dependent effect of gamma irradiation on Cryptosporidium parvum development in neonatal mice and newborn calves. In mice, C. parvum oocysts exposed to 200 Gy showed nearly complete inability to develop as measured by C. parvum-specific quantitative PCR of ileal ti...

Cloning and expression of gene encoding P23 protein from Cryptosporidium parvum

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Dinh Thi Bich Lan

2014-12-01

Full Text Available We cloned the cp23 gene coding P23 (glycoprotein from Cryptosporidium parvum isolated from Thua Thien Hue province, Vietnam. The coding region of cp23 gene from C. parvum is 99% similar with cp23 gene deposited in NCBI (accession number: U34390. SDS-PAGE and Western blot analysis showed that the cp23 gene in E. coli BL21 StarTM (DE3 produced polypeptides with molecular weights of approximately 37, 40 and 49 kDa. These molecules may be non-glycosylated or glycosylated P23 fusion polypeptides. Recombinant P23 protein purified by GST (glutathione S-transferase affinity chromatography can be used as an antigen for C. parvum antibody production as well as to develop diagnostic kit for C. parvum.

Ureaplasma parvum causes hyperammonemia in a pharmacologically immunocompromised murine model.

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Wang, X; Greenwood-Quaintance, K E; Karau, M J; Block, D R; Mandrekar, J N; Cunningham, S A; Mallea, J M; Patel, R

2017-03-01

A relationship between hyperammonemia and Ureaplasma infection has been shown in lung transplant recipients. We have demonstrated that Ureaplasma urealyticum causes hyperammonemia in a novel immunocompromised murine model. Herein, we determined whether Ureaplasma parvum can do the same. Male C3H mice were given mycophenolate mofetil, tacrolimus, and prednisone for 7 days, and then challenged with U. parvum intratracheally (IT) and/or intraperitoneally (IP), while continuing immunosuppression over 6 days. Plasma ammonia concentrations were determined and compared using Wilcoxon rank-sum tests. Plasma ammonia concentrations of immunosuppressed mice challenged IT/IP with spent broth (median, 188 μmol/L; range, 102-340 μmol/L) were similar to those of normal (median, 226 μmol/L; range, 154-284 μmol/L, p > 0.05), uninfected immunosuppressed (median, 231 μmol/L; range, 122-340 μmol/L, p > 0.05), and U. parvum IT/IP challenged immunocompetent (median, 226 μmol/L; range, 130-330 μmol/L, p > 0.05) mice. Immunosuppressed mice challenged with U. parvum IT/IP (median 343 μmol/L; range 136-1,000 μmol/L) or IP (median 307 μmol/L; range 132-692 μmol/L) had higher plasma ammonia concentrations than those challenged IT/IP with spent broth (p < 0.001). U. parvum can cause hyperammonemia in pharmacologically immunocompromised mice.

Staphylococcus aureus shifts towards commensalism in response to Corynebacterium species

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Matthew M Ramsey

2016-08-01

Full Text Available Staphylococcus aureus–human interactions result in a continuum of outcomes from commensalism to pathogenesis. S. aureus is a clinically important pathogen that asymptomatically colonizes ~25% of humans as a member of the nostril and skin microbiota, where it resides with other bacteria including commensal Corynebacterium species. Commensal Corynebacterium spp. are also positively correlated with S. aureus in chronic polymicrobial diabetic foot infections, distinct from acute monomicrobial S. aureus infections. Recent work by our lab and others indicates that microbe-microbe interactions between S. aureus and human skin/nasal commensals, including Corynebacterium species, affect S. aureus behavior and fitness. Thus, we hypothesized that S. aureus interactions with Corynebacterium spp. diminish S. aureus virulence. We tested this by assaying for changes in S. aureus gene expression during in vitro mono- versus coculture with Corynebacterium striatum, a common skin and nasal commensal. We observed a broad shift in S. aureus gene transcription during in vitro growth with C. striatum, including increased transcription of genes known to exhibit increased expression during human nasal colonization and decreased transcription of virulence genes. S. aureus uses several regulatory pathways to transition between commensal and pathogenic states. One of these, the quorum signal accessory gene regulator (agr system, was strongly inhibited in response to Corynebacterium spp. Phenotypically, S. aureus exposed to C. striatum exhibited increased adhesion to epithelial cells, reflecting a commensal state, and decreased hemolysin activity, reflecting an attenuation of virulence. Consistent with this, S. aureus displayed diminished fitness in experimental in vivo coinfection with C. striatum when compared to monoinfection. These data support a model in which S. aureus shifts from virulence towards a commensal state when exposed to commensal Corynebacterium species.

Improvement of biological nitrogen removal with nitrate-dependent Fe(II) oxidation bacterium Aquabacterium parvum B6 in an up-flow bioreactor for wastewater treatment.

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Zhang, Xiaoxin; Li, Ang; Szewzyk, Ulrich; Ma, Fang

2016-11-01

Aquabacterium parvum strain B6 exhibited efficient nitrate-dependent Fe(II) oxidation ability using nitrate as an electron acceptor. A continuous up-flow bioreactor that included an aerobic and an anoxic section was constructed, and strain B6 was added to the bioreactor as inocula to explore the application of microbial nitrate-dependent Fe(II) oxidizing (NDFO) efficiency in wastewater treatment. The maximum NRE (anoxic section) and TNRE of 46.9% and 79.7%, respectively, could be obtained at a C/N ratio of 5.3:1 in the influent with HRT of 17. Meanwhile, the taxonomy composition of the reactor was assessed, as well. The NDFO metabolism of strain B6 could be expected because of its relatively dominant position in the anoxic section, whereas potential heterotrophic nitrification and aerobic denitrification developed into the prevailing status in the aerobic section after 50days of continuous operation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prymnesium parvum exotoxins affect the grazing and viability of the calanoid copepod Eurytemora affinis

DEFF Research Database (Denmark)

Sopanen, S.; Koski, Marja; Uronen, P.

2008-01-01

The calanoid copepod Eurytemora affinis from the northern Baltic Sea was exposed to cell-free filtrates of the toxic haptophyte Prymnesium parvum as well as to cell mixtures of P. parvum and Rhodomonas salina. To test the effects of P. parvum exudates and allelopathy on selective grazers, copepods...... cultures were grown in nutrient-balanced (+NP) or limited (-N or -P) media to obtain different levels of toxicity. Survival, ingestion, faecal pellet production rates and egg production were measured over 3 d, together with measurements of P. parvum toxicity (hemolytic activity) (HA). Most of the copepods...... on grazers, and these effects are stronger under nutrient-depleted conditions; however, the presence of good-quality food lowers harmful effects for copepods. The negative effects caused either by direct intoxication or by food limitation following from strong allelopathic effects of P. parvum on other...

Cryptosporidium parvum, a potential cause of colic adenocarcinoma

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Pinon Anthony

2007-11-01

Full Text Available Abstract Background Cryptosporidiosis represents a major public health problem. This infection has been reported worldwide as a frequent cause of diarrhoea. Particularly, it remains a clinically significant opportunistic infection among immunocompromised patients, causing potentially life-threatening diarrhoea in HIV-infected persons. However, the understanding about different aspects of this infection such as invasion, transmission and pathogenesis is problematic. Additionally, it has been difficult to find suitable animal models for propagation of this parasite. Efforts are needed to develop reproducible animal models allowing both the routine passage of different species and approaching unclear aspects of Cryptosporidium infection, especially in the pathophysiology field. Results We developed a model using adult severe combined immunodeficiency (SCID mice inoculated with Cryptosporidium parvum or Cryptosporidium muris while treated or not with Dexamethasone (Dex in order to investigate divergences in prepatent period, oocyst shedding or clinical and histopathological manifestations. C. muris-infected mice showed high levels of oocysts excretion, whatever the chemical immunosuppression status. Pre-patent periods were 11 days and 9.7 days in average in Dex treated and untreated mice, respectively. Parasite infection was restricted to the stomach, and had a clear preferential colonization for fundic area in both groups. Among C. parvum-infected mice, Dex-treated SCID mice became chronic shedders with a prepatent period of 6.2 days in average. C. parvum-inoculated mice treated with Dex developed glandular cystic polyps with areas of intraepithelial neoplasia, and also with the presence of intramucosal adenocarcinoma. Conclusion For the first time C. parvum is associated with the formation of polyps and adenocarcinoma lesions in the gut of Dex-treated SCID mice. Additionally, we have developed a model to compare chronic muris and parvum

Infection by Cryptosporidium parvum in renal patients submitted to renal transplant or hemodialysis

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Chieffi Pedro Paulo

1998-01-01

Full Text Available The frequency of infection by Cryptosporidium parvum was determined in two groups of renal patients submitted to immunosuppression. One group consisted of 23 renal transplanted individuals, and the other consisted of 32 patients with chronic renal insufficiency, periodically submitted to hemodialysis. A third group of 27 patients with systemic arterial hypertension, not immunosuppressed, was used as control. During a period of 18 months all the patients were submitted to faecal examination to detect C. parvum oocysts, for a total of 1 to 6 tests per patient. The results showed frequencies of C. parvum infection of 34.8%, 25% and 17.4%, respectively, for the renal transplanted group, the patients submitted to hemodialysis and the control group. Statistical analysis showed no significant differences among the three groups even though the frequency of C. parvum infection was higher in the transplanted group. However, when the number of fecal samples containing C. parvum oocysts was taken in account, a significantly higher frequency was found in the renal transplanted group.

Review of Cervi Cornu Parvum Pharmacopuncture in Korean Medicine

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Lee Dong-Jin

2013-06-01

Full Text Available Objective: The endpoint of this review is to investigate existing studies of Cervi cornu parvum (CCP pharmacopuncture within Korean medicine journals in order to present a better research method in the future. Methods: We searched all the papers through six Korean electrical databases that included the title of "Cervi cornu parvum pharmacopuncture" or "Cervi cornu parvum aqua-acupuncture". Articles that had been published until December 2012 were largely divided into experimental studies and clinical studies. Results: Fifty-three (53 experimental studies and six clinical studies were found. The number of published articles has been constantly increasing. Many of the experimental studies demonstrated anti-inflammatory effects for arthritis, and most of the clinical studies dealt with musculoskeletal problems. Conclusion: Various therapeutically significant effects of the CCP pharmacopuncture have been found through this review; however, more systematic clinical studies on the CCP pharmacopuncture seem to be necessary to substantially support its clinical effects.

[Skin and Soft Tissue Infections Due to Corynebacterium ulcerans - Case Reports].

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Jenssen, Christian; Schwede, Ilona; Neumann, Volker; Pietsch, Cristine; Handrick, Werner

2017-10-01

History and clinical findings  We report on three patients suffering from skin and soft tissue infections of the legs due to toxigenic Corynebacterium ulcerans strains. In all three patients, there was a predisposition due to chronic diseases. Three patients had domestic animals (cat, dog) in their households. Investigations and diagnosis  A mixed bacterial flora including Corynebacterium ulcerans was found in wound swab samples. Diphtheric toxin was produced by the Corynebacterium ulcerans strains in all three cases. Treatment and course  In all three patients, successful handling of the skin and soft tissue infections was possible by combining local treatment with antibiotics. Diphtheria antitoxin was not administered in any case. Conclusion  Based on a review of the recent literature pathogenesis, clinical symptoms and signs, diagnostics and therapy of skin and soft tissue infections due to Corynebacterium ulcerans are discussed. Corynebacterium ulcerans should be considered as a potential cause of severe skin and soft tissue infections. Occupational or domestic animal contacts should be evaluated. © Georg Thieme Verlag KG Stuttgart · New York.

Evaluation of fenbendazole for treatment of Giardia infection in cats concurrently infected with Cryptosporidium parvum.

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Keith, Carey L; Radecki, Steven V; Lappin, Michael R

2003-08-01

To determine whether fenbendazole effectively eliminates Giardia organisms from chronically infected cats that have a concurrent Cryptosporidium parvum infection. 16 clinically normal cats. Eight cats with chronic concurrent Giardia and C parvum infections received fenbendazole (50 mg/kg, PO, q 24 h) for 5 days (treatment-group cats). Feces from each cat were collected and processed 3 days weekly for 23 days after treatment. By use of an immunofluorescent assay for detection of Giardia lamblia cysts and C parvum oocysts, organism numbers were counted and scored. Fecal results from treatment-group cats were compared with those of 8 untreated cats with Giardia infection but no C parvum infection (control-group cats). Four of 8 treatment-group cats had consistently negative results for Giardia infection after treatment. These 4 cats had consistently positive results for C parvum oocysts prior to treatment and consistently negative results after treatment. One treatment-group cat had positive results for cysts on all fecal samples, and 3 treatment-group cats had 1 to 3 negative results and then resumed shedding large numbers of cysts; each of these cats had consistently positive results for C parvum oocysts. When compared with control-group cats, treatment-group cats shed less Giardia cysts during week 1 after treatment but not during week 2. Administration of fenbendazole decreases Giardia cyst shedding to less than detectable numbers in some cats. In our study, persistent C parvum infection may have been associated with failure of fenbendazole to eliminate Giardia infection.

Ureaplasma parvum infection alters filamin a dynamics in host cells

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Brown Mary B

2011-04-01

Full Text Available Abstract Background Ureaplasmas are among the most common bacteria isolated from the human urogenital tract. Ureaplasmas can produce asymptomatic infections or disease characterized by an exaggerated inflammatory response. Most investigations have focused on elucidating the pathogenic potential of Ureaplasma species, but little attention has been paid to understanding the mechanisms by which these organisms are capable of establishing asymptomatic infection. Methods We employed differential proteome profiling of bladder tissues from rats experimentally infected with U. parvum in order to identify host cell processes perturbed by colonization with the microbe. Tissues were grouped into four categories: sham inoculated controls, animals that spontaneously cleared infection, asymptomatic urinary tract infection (UTI, and complicated UTI. One protein that was perturbed by infection (filamin A was used to further elucidate the mechanism of U. parvum-induced disruption in human benign prostate cells (BPH-1. BPH-1 cells were evaluated by confocal microscopy, immunoblotting and ELISA. Results Bladder tissue from animals actively colonized with U. parvum displayed significant alterations in actin binding proteins (profilin 1, vinculin, α actinin, and filamin A that regulate both actin polymerization and cell cytoskeletal function pertaining to focal adhesion formation and signal transduction (Fisher's exact test, P U. parvum perturbed the regulation of filamin A. Specifically, infected BPH-1 cells exhibited a significant increase in filamin A phosphorylated at serine2152 (P ≤ 0.01, which correlated with impaired proteolysis of the protein and its normal intracellular distribution. Conclusion Filamin A dynamics were perturbed in both models of infection. Phosphorylation of filamin A occurs in response to various cell signaling cascades that regulate cell motility, differentiation, apoptosis and inflammation. Thus, this phenomenon may be a useful

J-GLOBAL MeSH Dictionary: Corynebacterium pseudotuberculosis [MeCab user dictionary for science technology term[Archive

Lifescience Database Archive (English)

Full Text Available MeCab user dictionary for science technology term Corynebacterium pseudotuberculosis... 名詞 一般 * * * * Corynebacterium pseudotuberculosis ... MeSH D016925 200906025325177003 C LS07 UNKNOWN_2 Corynebacterium pseudotuberculosis

Water stress exacerbates the severity of Botryosphaeria dieback in grapevines infected by Neofusicoccum parvum

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Botryosphaeria dieback (causal fungus Neofusicoccum parvum) is a detrimental grapevine trunk disease, causing internal wood degradation, killing shoots, and reducing yields. We examined the interactive effects of drought and N. parvum infection, common vineyard stresses, on wood-lesion development. ...

Bacterial loads of Ureaplasma parvum contribute to the development of inflammatory responses in the male urethra.

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Deguchi, Takashi; Shimada, Yasushi; Horie, Kengo; Mizutani, Kohsuke; Seike, Kensaku; Tsuchiya, Tomohiro; Yokoi, Shigeaki; Yasuda, Mitsuru; Ito, Shin

2015-12-01

Ureaplasma parvum, which has been recognised as a coloniser in the male urethra, is detected in some men with non-gonococcal urethritis. In this study, we quantified the 16 S rRNA genes of U. parvum by a real-time polymerase chain reaction-based assay in first-voided urine from 15 symptomatic and 38 asymptomatic men who were positive only for U. parvum. We also determined the leukocyte counts by automated quantitative urine particle analysis in their first-voided urine. Positive correlations were observed between copies of the 16 S rRNA genes of U. parvum/ml and the leukocyte counts/µl in first-voided urine (p = 0.0019). The loads of ≥10(4) copies of the 16 S rRNA gene/ml, corresponding to ≥5 × 10(3) cells of U. parvum/ml, were significantly associated with the presence of ≥12.5 leukocytes/µl in first-voided urine that might document the presence of inflammatory responses in the urethra. However, a large portion of the subjects (83.0%) had bacterial loads of <5 × 10(3) cells of U. parvum/ml, and 79.5% of them showed <12.5 leukocytes/µl. The ambiguity of the pathogenic role of U. parvum in non-gonococcal urethritis could, in part, be due to its low bacterial loads, which might not give rise to inflammatory responses in the male urethra. © The Author(s) 2015.

THE EFFICACY OF THREE MEDICINAL PLANTS; GARLIC, GINGER AND MIRAZID AND A CHEMICAL DRUG METRONIDAZOLE AGAINST CRYPTOSPORIDIUM PARVUM: II-HISTOLOGICAL CHANGES.

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Abouel-Nour, Mohamed F; El-Shewehy, Dina Magdy M; Hamada, Shadia F; Morsy, Tosson A

2016-04-01

Cryptosporidiosis parvum is a zoonotic protozoan parasite infects intestinal epithelial cells of man and animals causing a major health problem. This study was oriented to evaluate the protective and curative capacity of garlic, ginger and mirazid in comparison with metronidazole drug (commercially known) against Cryptosporidium in experimental mice. Male Swiss Albino mice experimentally infected with C. parvum were treated with medicinal plants extracts (Ginger, Mirazid, and Garlic) as compared to chemical drug Metronidazole. Importantly, C. parvum-infected mice treated with ginger, Mirazid, garlic and metronidazole showed a complete elimination in shedding oocysts by 9th day PI. The reduction and elimination of shedding oocysts in response to the treatments might be attributable to a direct effect on parasite growth in intestines, sexual phases production and/or the formation of oocysts. The results were evaluated histopathological examination of ideum section of control mice (uninfected, untreated) displayed normal architecture of the villi. Examiination of infected mice ileum section (infected, untreated) displayed histopathological alterations from uninfected groups. Examination of ileum section prepared from mice treated with garlic, ginger, mirazid, and metronidazole displayed histopathological alterations from that of the control groups, and showed marked histologic correction in the pattern with the four regimes used in comparison to control mice. Garlic successfully eradicated oocysts of infected mice from stool and intestine. Supplementation of ginger to infected mice markedly corrected elevation in the inflammatory risk factors and implied its potential antioxidant, anti-inflammatory and immunomodulatory capabilities. Infected mice treated with ginger, mirazid, garlic and metronidazole showed significant symptomatic improvements during treatment.

Cryptosporidium parvum-induced ileo-caecal adenocarcinoma and Wnt signaling in a mouse model

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Sadia Benamrouz

2014-06-01

Full Text Available Cryptosporidium species are apicomplexan protozoans that are found worldwide. These parasites constitute a large risk to human and animal health. They cause self-limited diarrhea in immunocompetent hosts and a life-threatening disease in immunocompromised hosts. Interestingly, Cryptosporidium parvum has been related to digestive carcinogenesis in humans. Consistent with a potential tumorigenic role of this parasite, in an original reproducible animal model of chronic cryptosporidiosis based on dexamethasone-treated or untreated adult SCID mice, we formerly reported that C. parvum (strains of animal and human origin is able to induce digestive adenocarcinoma even in infections induced with very low inoculum. The aim of this study was to further characterize this animal model and to explore metabolic pathways potentially involved in the development of C. parvum-induced ileo-caecal oncogenesis. We searched for alterations in genes or proteins commonly involved in cell cycle, differentiation or cell migration, such as β-catenin, Apc, E-cadherin, Kras and p53. After infection of animals with C. parvum we demonstrated immunohistochemical abnormal localization of Wnt signaling pathway components and p53. Mutations in the selected loci of studied genes were not found after high-throughput sequencing. Furthermore, alterations in the ultrastructure of adherens junctions of the ileo-caecal neoplastic epithelia of C. parvum-infected mice were recorded using transmission electron microscopy. In conclusion, we found for the first time that the Wnt signaling pathway, and particularly the cytoskeleton network, seems to be pivotal for the development of the C. parvum-induced neoplastic process and cell migration of transformed cells. Furthermore, this model is a valuable tool in understanding the host-pathogen interactions associated with the intricate infection process of this parasite, which is able to modulate host cytoskeleton activities and several host

Modification of glomerular immune complex deposition in mice by activation of the reticuloendothelial system.

OpenAIRE

Barcelli, U; Rademacher, R; Ooi, Y M; Ooi, B S

1981-01-01

To determine the effect of activation of the reticuloendothelial system on the localization of immune complexes in the kidney, a model of passive serum sickness nephritis in the mouse was used, with activation of the reticuloendothelial system with Corynebacterium parvum. Groups of mice, control and C. parvum-treated animals, were injected with BSA-125I-anti-BSA complexes containing 3 mg 125I-anti-BSA. Blood was obtained at 5 min, at 3 h, and at 12 h, when the animals were killed. Blood conce...

Diarrhea due to Cryptosporidium parvum in immunocompromised ...

African Journals Online (AJOL)

Objective: The objective of this study is to search for Cryptosporidium parvum in Sudanese immunocompromised and immunocompetent patients presenting with diarrhea. Methods: Two hundred and thirteen stool specimens were collected from different groups of patients presenting with diarrhea and healthy control ...

Antibody responses to a Cryptosporidium parvum rCP15/60 vaccine

OpenAIRE

Alexandra J. Burton; Daryl V. Nydam; Gary Jones; Jennifer Zambriski; Thomas C. Linden; Graham Cox; Randy Davis; Alicia Brown; Dwight D. Bowman

2009-01-01

Cryptosporidium parvum is a zoonotic apicomplexa-protozoan pathogen that causes gastroenteritis and diarrhoea in mammals worldwide. The organism is transmitted by ingestion of oocysts, which are shed in faeces, and completes its lifecycle in a single host.^1^ C. parvum is ubiquitous on dairy operations worldwide and is one of the leading causes of diarrhoea in calves on these farms.^2,3^ Here, for the first time, we describe the antibody response in a large group of cows to a recombinant C. p...

Virulence of geographically different Cryptosporidium parvum isolates in experimental animal model

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Sayed, Fatma G.; Hamza, Amany I.; Galal, Lamia A.; Sayed, Douaa M.; Gaber, Mona

2016-10-01

Cryptosporidium parvum is a coccidian parasite which causes gastrointestinal disease in humans and a variety of other mammalian species. Several studies have reported different degrees of pathogenicity and virulence among Cryptosporidium species and isolates of the same species as well as evidence of variation in host susceptibility to infection. The study aimed to investigate infectivity and virulence of two Cryptosporidium parvum “Iowa isolate” (CpI) and a “local water isolate” (CpW). Thirty-three Swiss albino mice have been divided into three groups: Negative control Group (C), the CpI group infected with “Iowa isolate “and the CpW group infected with C. parvum oocysts isolated from a local water supply. Infectivity and virulence have been measured by evaluating clinical, parasitological and histological aspects of infection. Significant differences were detected regarding oocysts shedding rate, clinical outcomes, and the histopathological picture of the intestine, lung, and brain. It was concluded that the local water isolate is significantly more virulent than the exported one.

Maternal intravenous treatment with either azithromycin or solithromycin clears Ureaplasma parvum from the amniotic fluid in an ovine model of intrauterine infection.

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Miura, Yuichiro; Payne, Matthew S; Keelan, Jeffrey A; Noe, Andres; Carter, Sean; Watts, Rory; Spiller, Owen B; Jobe, Alan H; Kallapur, Suhas G; Saito, Masatoshi; Stock, Sarah J; Newnham, John P; Kemp, Matthew W

2014-09-01

Intrauterine infection with Ureaplasma spp. is strongly associated with preterm birth and adverse neonatal outcomes. We assessed whether combined intraamniotic (IA) and maternal intravenous (IV) treatment with one of two candidate antibiotics, azithromycin (AZ) or solithromycin (SOLI), would eradicate intrauterine Ureaplasma parvum infection in a sheep model of pregnancy. Sheep with singleton pregnancies received an IA injection of U. parvum serovar 3 at 85 days of gestational age (GA). At 120 days of GA, animals (n=5 to 8/group) received one of the following treatments: (i) maternal IV SOLI with a single IA injection of vehicle (IV SOLI only); (ii) maternal IV SOLI with a single IA injection of SOLI (IV+IA SOLI); (iii) maternal IV AZ and a single IA injection of vehicle (IV AZ only); (iv) maternal IV AZ and a single IA injection of AZ (IV+IA AZ); or (v) maternal IV and single IA injection of vehicle (control). Lambs were surgically delivered at 125 days of GA. Treatment efficacies were assessed by U. parvum culture, quantitative PCR, enzyme-linked immunosorbent assay, and histopathology. Amniotic fluid (AF) from all control animals contained culturable U. parvum. AF, lung, and chorioamnion from all AZ- or SOLI-treated animals (IV only or IV plus IA) were negative for culturable U. parvum. Relative to the results for the control, the levels of expression of interleukin 1β (IL-1β), IL-6, IL-8, and monocyte chemoattractant protein 2 (MCP-2) in fetal skin were significantly decreased in the IV SOLI-only group, the MCP-1 protein concentration in the amniotic fluid was significantly increased in the IV+IA SOLI group, and there was no significant difference in the histological inflammation scoring of lung or chorioamnion among the five groups. In the present study, treatment with either AZ or SOLI (IV only or IV+IA) effectively eradicated macrolide-sensitive U. parvum from the AF. There was no discernible difference in antibiotic therapy efficacy between IV-only and IV

Prymnesium parvum revisited: relationship between allelopathy, ichthyotoxicity, and chemical profiles in 5 strains

DEFF Research Database (Denmark)

Blossom, Hannah E.; Rasmussen, Silas Anselm; Andersen, Nikolaj Gedsted

2014-01-01

used forbioassay guided purification of new ichthyotoxins. Here we tested the hypothesis that allelopathy isrelated to ichthyotoxicity and thus that a microalgal bioassay can be used as a proxy for ichthyotoxicityby comparing the toxicity of five strains of Prymnesium parvum toward rainbow trout...... to P.parvum with EC50s ranging from 6 × 103to 40 × 103cells ml−1, compared to the test alga where LC50sranged from 30 × 103to nearly non-toxic at 500 × 103cells ml−1. In addition, the cellular concentrationsof two recently suggested ichthyotoxins produced by P. parvum, the “golden algae toxins”, GAT...... of the five P. parvum strains above the limit of detection, nor was it found in a13C-labeled strain. Instead we document thatoleamide can easily be extracted from plastic materials, which may have been the source of oleamidereported previously....

A chronicle of a killer alga in the west: ecology, assessment, and management of Prymnesium parvum blooms

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Roelke, D.L.; Barkoh, Aaron; Brooks, B.W.; Grover, J.P.; Hambright, K.D.; LaClaire, John W.; Moeller, Peter D.R.; Patino, Reynaldo

2015-01-01

Since the mid-1980s, fish-killing blooms ofPrymnesium parvum spread throughout the USA. In the south central USA, P. parvum blooms have commonly spanned hundreds of kilometers. There is much evidence that physiological stress brought on by inorganic nutrient limitation enhances toxicity. Other factors influence toxin production as well, such as stress experienced at low salinity and temperature. A better understanding of toxin production by P. parvum remains elusive and the identities and functions of chemicals produced are unclear. This limits our understanding of factors that facilitated the spread of P. parvum blooms. In the south central USA, not only is there evidence that the spread of blooms was controlled, in part, by migration limitation. But there are also observations that suggest changed environmental conditions, primarily salinity, facilitated the spread of blooms. Other factors that might have played a role include altered hydrology and nutrient loading. Changes in water hardness, herbicide use, system pH, and the presence of toxin-resistant and/or P. parvum-inhibiting plankton may also have played a role. Management of P. parvum in natural systems has yet to be attempted, but may be guided by successes achieved in small impoundments and mesocosm experiments that employed various chemical and hydraulic control approaches.

Ureaplasma urealyticum and U. parvum in sexually active women attending public health clinics in Brazil.

Science.gov (United States)

Lobão, T N; Campos, G B; Selis, N N; Amorim, A T; Souza, S G; Mafra, S S; Pereira, L S; Dos Santos, D B; Figueiredo, T B; Marques, L M; Timenetsky, J

2017-08-01

Ureaplasma urealyticum and U. parvum have been associated with genital infections. The purpose of this study was to detect the presence of ureaplasmas and other sexually transmitted infections in sexually active women from Brazil and relate these data to demographic and sexual health, and cytokines IL-6 and IL-1β. Samples of cervical swab of 302 women were examined at the Family Health Units in Vitória da Conquista. The frequency of detection by conventional PCR was 76·2% for Mollicutes. In qPCR, the frequency found was 16·6% for U. urealyticum and 60·6% U. parvum and the bacterial load of these microorganisms was not significantly associated with signs and symptoms of genital infection. The frequency found for Trichomonas vaginalis, Neisseria gonorrhoeae, Gardnerella vaginalis and Chlamydia trachomatis was 3·0%, 21·5%, 42·4% and 1·7%, respectively. Higher levels of IL-1β were associated with control women colonized by U. urealyticum and U. parvum. Increased levels of IL-6 were associated with women who exhibited U. parvum. Sexually active women, with more than one sexual partner in the last 3 months, living in a rural area were associated with increased odds of certain U. parvum serovar infection.

Movement of Cryptosporidium parvum Oocysts through Soils without Preferential Pathways: Exploratory Test

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Christophe J. G. Darnault

2017-06-01

Full Text Available Groundwater contamination by oocysts of the waterborne pathogen Cryptosporidium parvum is a significant cause of animal and human disease worldwide. Although research has been undertaken in the past to determine how specific physical and chemical properties of soils affect the risk of groundwater contamination by C. parvum, there is as yet no clear conclusion concerning the range of mobility of C. parvum that one should expect in field soils. In this context, the key objective of this research was to determine the magnitude of C. parvum transport in a number of soils, under conditions in which fast and preferential transport has been successfully prevented. C. parvum oocysts were applied at the surface of different soils and subjected to artificial rainfall. Apparently for the first time, quantitative PCR was used to detect and enumerate oocysts in the soil columns and in the leachates. The transport of oocysts by infiltrating water, and the considerable retention of oocysts in soil was demonstrated for all soils, although differences in the degree of transport were observed with soils of different types. More oocysts were found in leachates from sandy loam soils than in leachates from loamy sand soils and the retention of oocysts in different soils did not significantly differ. The interaction of various processes of the hydrologic system and biogeochemical mechanisms contributed to the transport of oocysts through the soil matrix. Results suggest that the interplay of clay, organic matter, and Ca2+ facilitates and mediates the transfer of organic matter from mineral surfaces to oocysts surface, resulting in the enhanced breakthrough of oocysts through matrices of sandy loam soils compared to those of loamy sand soils. Although the number of occysts that penetrate the soil matrix account for only a small percentage of initial inputs, they still pose a significant threat to human health, especially in groundwater systems with a water table not

Host genetic background impacts disease outcome during intrauterine infection with Ureaplasma parvum.

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Maria von Chamier

Full Text Available Ureaplasma parvum, an opportunistic pathogen of the human urogenital tract, has been implicated in contributing to chorioamnionitis, fetal morbidity, and fetal mortality. It has been proposed that the host genetic background is a critical factor in adverse pregnancy outcome as sequela to U. parvum intra-amniotic infection. To test this hypothesis we assessed the impact of intrauterine U. parvum infection in the prototypical TH1/M1 C57BL/6 and TH2/M2 BALB/c mouse strain. Sterile medium or U. parvum was inoculated into each uterine horn and animals were evaluated for intra-amniotic infection, fetal infection, chorioamnionitis and fetal pathology at 72 hours post-inoculation. Disease outcome was assessed by microbial culture, in situ detection of U. parvum in fetal and utero-placental tissues, grading of chorioamnionitis, and placental gene expression of IL-1α, IL-1β, IL-6, TNF-α, S100A8, and S100A9. Placental infection and colonization rates were equivalent in both strains. The in situ distribution of U. parvum in placental tissues was also similar. However, a significantly greater proportion of BALB/c fetuses were infected (P<0.02. C57BL/6 infected animals predominantly exhibited mild to moderate chorioamnionitis (P<0.0001, and a significant reduction in placental expression of IL-1α, IL-1β, IL-6, TNF-α, S100A8, and S100A9 compared to sham controls (P<0.02. Conversely, severe protracted chorioamnionitis with cellular necrosis was the predominant lesion phenotype in BALB/c mice, which also exhibited a significant increase in placental expression of IL-1α, IL-1β, IL-6, TNF-α, S100A8, and S100A9 (P<0.01. Fetal pathology in BALB/c was multi-organ and included brain, lung, heart, liver, and intestine, whereas fetal pathology in C57BL/6 was only detected in the liver and intestines. These results confirm that the host genetic background is a major determinant in ureaplasmal induced chorioamnionitis with fetal infection and fetal inflammatory

Insight of Genus Corynebacterium: Ascertaining the Role of Pathogenic and Non-pathogenic Species.

Science.gov (United States)

Oliveira, Alberto; Oliveira, Leticia C; Aburjaile, Flavia; Benevides, Leandro; Tiwari, Sandeep; Jamal, Syed B; Silva, Arthur; Figueiredo, Henrique C P; Ghosh, Preetam; Portela, Ricardo W; De Carvalho Azevedo, Vasco A; Wattam, Alice R

2017-01-01

This review gathers recent information about genomic and transcriptomic studies in the Corynebacterium genus, exploring, for example, prediction of pathogenicity islands and stress response in different pathogenic and non-pathogenic species. In addition, is described several phylogeny studies to Corynebacterium , exploring since the identification of species until biological speciation in one species belonging to the genus Corynebacterium . Important concepts associated with virulence highlighting the role of Pld protein and Tox gene. The adhesion, characteristic of virulence factor, was described using the sortase mechanism that is associated to anchorage to the cell wall. In addition, survival inside the host cell and some diseases, were too addressed for pathogenic corynebacteria, while important biochemical pathways and biotechnological applications retain the focus of this review for non-pathogenic corynebacteria. Concluding, this review broadly explores characteristics in genus Corynebacterium showing to have strong relevance inside the medical, veterinary, and biotechnology field.

High-resolution melt PCR analysis for genotyping of Ureaplasma parvum isolates directly from clinical samples.

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Payne, Matthew S; Tabone, Tania; Kemp, Matthew W; Keelan, Jeffrey A; Spiller, O Brad; Newnham, John P

2014-02-01

Ureaplasma sp. infection in neonates and adults underlies a variety of disease pathologies. Of the two human Ureaplasma spp., Ureaplasma parvum is clinically the most common. We have developed a high-resolution melt (HRM) PCR assay for the differentiation of the four serovars of U. parvum in a single step. Currently U. parvum strains are separated into four serovars by sequencing the promoter and coding region of the multiple-banded antigen (MBA) gene. We designed primers to conserved sequences within this region for PCR amplification and HRM analysis to generate reproducible and distinct melt profiles that distinguish clonal representatives of serovars 1, 3, 6, and 14. Furthermore, our HRM PCR assay could classify DNA extracted from 74 known (MBA-sequenced) test strains with 100% accuracy. Importantly, HRM PCR was also able to identify U. parvum serovars directly from 16 clinical swabs. HRM PCR performed with DNA consisting of mixtures of combined known serovars yielded profiles that were easily distinguished from those for single-serovar controls. These profiles mirrored clinical samples that contained mixed serovars. Unfortunately, melt curve analysis software is not yet robust enough to identify the composition of mixed serovar samples, only that more than one serovar is present. HRM PCR provides a single-step, rapid, cost-effective means to differentiate the four serovars of U. parvum that did not amplify any of the known 10 serovars of Ureaplasma urealyticum tested in parallel. Choice of reaction reagents was found to be crucial to allow sufficient sensitivity to differentiate U. parvum serovars directly from clinical swabs rather than requiring cell enrichment using microbial culture techniques.

Biochemical aspects of the immunomodular action in irradiated survival mice with 60C gama irradiation

International Nuclear Information System (INIS)

Garcia Agudo, N.L. del M. de.

1983-01-01

The radioprotective action of Calmetti-Guerin bacillus (BCG), Corynebacterium parvum, Escherichia coli Lipopolysccharides (LPS) and peptone proteose was evaluated. A single injection of the macrophage activiting agents prior to 60 Co whole-body irradiation increased the survival rate of mice in the lethal dose range. (L.M.J.) [pt

Ureaplasma parvum and Ureaplasma urealyticum detected with the same frequency among women with and without symptoms of urogenital tract infection.

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Marovt, M; Keše, D; Kotar, T; Kmet, N; Miljković, J; Šoba, B; Matičič, M

2015-06-01

There is mounting evidence stating that Ureaplasma urealyticum causes non-gonococcal urethritis in males, whereas Ureaplasma parvum does not seem to be of clinical significance. However, the clinical role of U. parvum and U. urealyticum in lower urogenital tract infections in females remains unclear. The aim of the study was to determine the frequency of U. parvum and U. urealyticum among 145 Ureaplasma spp. culture-positive women with symptoms of lower urogenital tract infection (n = 75) and those without (n = 70), and to determine possible associations between the detection of U. parvum and U. urealyticum with selected characteristics. Endocervical, urethral, and vaginal swabs, and first voided urine were obtained. Polymerase chain reaction (PCR) was performed to differentiate ureaplasmas. No significant association between the detection of U. parvum or U. urealyticum and symptom status was found. Significantly more women aged 25 years and younger were infected with U. urealyticum (23.4 %) compared to those aged above 25 years (9.2 %) [odds ratio (OR) 3.0 (1.1; 8.1); p = 0.03] and significantly less women aged 25 years and younger (83.5 %) were infected with U. parvum compared to those aged above 25 years (95.5 %) [OR 0.2 (0.1; 0.9); p = 0.03]. The detection of Chlamydia trachomatis was significantly associated to both U. parvum and U. urealyticum (p = 0.021), and to U. parvum alone with borderline significance (p = 0.063). Although neither U. parvum nor U. urealyticum seem to cause symptoms in females, their role in the female urogenital tract remains unknown, taking into account their ubiquity, possible augmentation of the urogenital microenvironment, and ascending capability to the sterile upper reproductive tract.

The Association of Cryptosporidium parvum With Suspended Sediments: Implications for Transport in Surface Waters

Science.gov (United States)

Searcy, K. E.; Packman, A. I.; Atwill, E. R.; Harter, T.

2003-12-01

Understanding the transport and fate of microorganisms in surface waters is of vital concern in protecting the integrity and safety of municipal water supply systems. The human pathogen Cryptosporidium parvum is a particular public health interest, as it is ubiquitous in the surface waters of the United States, it can persist for long periods in the environment, and it is difficult to disinfect in water treatment plants. Due to its small size (5 um), low specific gravity (1.05 g/cm3), and negative surface charge, C. parvum oocysts are generally considered to move through watersheds from their source to drinking water reservoirs with little attenuation. However, the transport of the oocysts in surface waters may be mediated by interactions with suspended sediments. Batch experiments were conducted to determine the extent of C. parvum oocyst attachment to several inorganic and organic sediments under varying water chemical conditions, and settling column experiments were performed to demonstrate how these associations influence the effective settling velocity of C. parvum oocysts. Results from these experiments showed that C. parvum oocysts do associate with inorganic and organic sediments and often settle at the rate of the suspended sediment. The size and surface charge of the host suspended sediment influenced the extent of oocyst attachment as oocysts preferentially associated with particles greater than 3 um, and fewer oocysts associated with particles having a highly negative surface charge. Background water chemical conditions including ionic strength, ion composition, and pH did not have a significant effect on oocyst attachment to suspended sediments.

SIALIDASE (NEURAMINIDASE) OF CORYNEBACTERIUM DIPHTHERIAE.

Science.gov (United States)

WARREN, L; SPEARING, C W

1963-11-01

Warren, Leonard (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.) and C. W. Spearing. Sialidase (neuraminidase) of Corynebacterium diphtheriae. J. Bacteriol. 86:950-955. 1963.-The characteristics of a sialidase produced by Corynebacterium diphtheriae were studied. The enzyme was partially purified from preparations of diphtheria toxin on a column of Sephadex G-75. By this means the lethal factor of diphtheria toxin was separated, in part, from the sialidase activity. There appeared to be a close immunological relationship between the sialidases of C. diphtheriae and clostridia, since a preparation of diphtheria antitoxin was as effective an inhibitor of diphtheria sialidase as of the sialidase of three species of clostridia. Conversely, antitoxin to clostridia inhibited diphtheria sialidase. Diphtheria antitoxin was essentially inactive toward influenza virus sialidase, and was completely inactive against purified sialidase of Vibrio cholerae. Removal of sialic acid from the proteins in a preparation of diphtheria antitoxin did not alter the inhibitory activity of the antitoxin against diphtheria sialidase. The enzyme operated optimally at pH 5.5 and did not require calcium ions for activity. The substrate specificity of diphtheria sialidase appears to be the same as that of other previously described sialidases.

Comparative evolutionary genomics of Corynebacterium with special reference to codon and amino acid usage diversities.

Science.gov (United States)

Pal, Shilpee; Sarkar, Indrani; Roy, Ayan; Mohapatra, Pradeep K Das; Mondal, Keshab C; Sen, Arnab

2018-02-01

The present study has been aimed to the comparative analysis of high GC composition containing Corynebacterium genomes and their evolutionary study by exploring codon and amino acid usage patterns. Phylogenetic study by MLSA approach, indel analysis and BLAST matrix differentiated Corynebacterium species in pathogenic and non-pathogenic clusters. Correspondence analysis on synonymous codon usage reveals that, gene length, optimal codon frequencies and tRNA abundance affect the gene expression of Corynebacterium. Most of the optimal codons as well as translationally optimal codons are C ending i.e. RNY (R-purine, N-any nucleotide base, and Y-pyrimidine) and reveal translational selection pressure on codon bias of Corynebacterium. Amino acid usage is affected by hydrophobicity, aromaticity, protein energy cost, etc. Highly expressed genes followed the cost minimization hypothesis and are less diverged at their synonymous positions of codons. Functional analysis of core genes shows significant difference in pathogenic and non-pathogenic Corynebacterium. The study reveals close relationship between non-pathogenic and opportunistic pathogenic Corynebaterium as well as between molecular evolution and survival niches of the organism.

Cryptosporidium parvum and Isopora belli infections among patients ...

African Journals Online (AJOL)

Objective: To assess the importance of Cryptosporidium parvum and Isospora belli infections as a cause of diarrhoea among patients admitted to the Medical Wards in Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi. Design: Prospective case control study. Subjects: One hundred and twenty one patients with ...

Intra-amniotic Ureaplasma parvum-Induced Maternal and Fetal Inflammation and Immune Responses in Rhesus Macaques.

Science.gov (United States)

Senthamaraikannan, Paranthaman; Presicce, Pietro; Rueda, Cesar M; Maneenil, Gunlawadee; Schmidt, Augusto F; Miller, Lisa A; Waites, Ken B; Jobe, Alan H; Kallapur, Suhas G; Chougnet, Claire A

2016-11-15

 Although Ureaplasma species are the most common organisms associated with prematurity, their effects on the maternal and fetal immune system remain poorly characterized.  Rhesus macaque dams at approximately 80% gestation were injected intra-amniotically with 10 7 colony-forming units of Ureaplasma parvum or saline (control). Fetuses were delivered surgically 3 or 7 days later. We performed comprehensive assessments of inflammation and immune effects in multiple fetal and maternal tissues.  Although U. parvum grew well in amniotic fluid, there was minimal chorioamnionitis. U. parvum colonized the fetal lung, but fetal systemic microbial invasion was limited. Fetal lung inflammation was mild, with elevations in CXCL8, tumor necrosis factor (TNF) α, and CCL2 levels in alveolar washes at day 7. Inflammation was not detected in the fetal brain. Significantly, U. parvum decreased regulatory T cells (Tregs) and activated interferon γ production in these Tregs in the fetus. It was detected in uterine tissue by day 7 and induced mild inflammation and increased expression of connexin 43, a gap junction protein involved with labor.  U. parvum colonized the amniotic fluid and caused uterine inflammation, but without overt chorioamnionitis. It caused mild fetal lung inflammation but had a more profound effect on the fetal immune system, decreasing Tregs and polarizing them toward a T-helper 1 phenotype. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Polymerase chain reaction-hybridization method using urease gene sequences for high-throughput Ureaplasma urealyticum and Ureaplasma parvum detection and differentiation.

Science.gov (United States)

Xu, Chen; Zhang, Nan; Huo, Qianyu; Chen, Minghui; Wang, Rengfeng; Liu, Zhili; Li, Xue; Liu, Yunde; Bao, Huijing

2016-04-15

In this article, we discuss the polymerase chain reaction (PCR)-hybridization assay that we developed for high-throughput simultaneous detection and differentiation of Ureaplasma urealyticum and Ureaplasma parvum using one set of primers and two specific DNA probes based on urease gene nucleotide sequence differences. First, U. urealyticum and U. parvum DNA samples were specifically amplified using one set of biotin-labeled primers. Furthermore, amine-modified DNA probes, which can specifically react with U. urealyticum or U. parvum DNA, were covalently immobilized to a DNA-BIND plate surface. The plate was then incubated with the PCR products to facilitate sequence-specific DNA binding. Horseradish peroxidase-streptavidin conjugation and a colorimetric assay were used. Based on the results, the PCR-hybridization assay we developed can specifically differentiate U. urealyticum and U. parvum with high sensitivity (95%) compared with cultivation (72.5%). Hence, this study demonstrates a new method for high-throughput simultaneous differentiation and detection of U. urealyticum and U. parvum with high sensitivity. Based on these observations, the PCR-hybridization assay developed in this study is ideal for detecting and discriminating U. urealyticum and U. parvum in clinical applications. Copyright © 2016 Elsevier Inc. All rights reserved.

Occurrence of two newly named oral treponemes - Treponema parvum and Treponema putidum - in primary endodontic infections.

Science.gov (United States)

Rôças, I N; Siqueira, J F

2005-12-01

Recent evidence from molecular genetic studies has revealed that oral Treponema species are involved in infections of endodontic origin. This study assessed the occurrence of two newly named oral treponemes - Treponema parvum and Treponema putidum - in primary endodontic infections using a culture-independent identification technique. Genomic DNA was isolated directly from clinical samples, and a 16S rRNA gene-based nested polymerase chain reaction (PCR) assay was used to determine the presence of T. parvum and T. putidum. Species-specific primer pairs were developed by aligning closely related 16S rRNA gene sequences. The specificity for each primer pair was validated by running PCR against a panel of oral bacteria and by sequence analysis of PCR products from positive clinical samples. T. parvum was detected in 52% of the root canals associated with chronic apical periodontitis, in 20% of the cases diagnosed as acute apical periodontitis, and in no abscessed case. In general, T. parvum was detected in 26% of the samples from primary endodontic infections. T. putidum was found in only one case of acute apical periodontitis (2% of the total number of cases investigated). The devised nested PCR protocol was able to identify both T. parvum and T. putidum directly in clinical samples and demonstrated that these two treponemes can take part in endodontic infections.

Prymnesium parvum revisited: Relationship between allelopathy, ichthyotoxicity, and chemical profiles in 5 strains

Energy Technology Data Exchange (ETDEWEB)

Blossom, Hannah E., E-mail: hblossom@bio.ku.dk [Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør (Denmark); Rasmussen, Silas A. [Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs Lyngby (Denmark); Andersen, Nikolaj G. [Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør (Denmark); Larsen, Thomas O.; Nielsen, Kristian F. [Department of Systems Biology, Technical University of Denmark, Søltofts Plads, Building 221, 2800 Kgs Lyngby (Denmark); Hansen, Per J. [Marine Biological Section, University of Copenhagen, Strandpromenaden 5, 3000 Helsingør (Denmark)

2014-12-15

Highlights: • Five strains of P. parvum were tested for toxicity towards rainbow trout and microalgae. • Toxicity towards microalgae was not correlated to toxicity towards fish. • A microalgal bioassay cannot be used as a reliable proxy for ichthyotoxicity. • Concentrations of GATs were low and not correlated to effects on fish or on algae. • P. parvum does not produce oleamide based on {sup 13}C labeling and extraction in glass. - Abstract: Bioassay-guided discovery of ichthyotoxic algal compounds using in vivo fish assays is labor intensive, costly, and highly regulated. Since the mode of action of most known algal-mediated fish-killing toxins is damage to the cell membranes in the gills, various types of cell-based bioassays are often used for bioassay guided purification of new ichthyotoxins. Here we tested the hypothesis that allelopathy is related to ichthyotoxicity and thus that a microalgal bioassay can be used as a proxy for ichthyotoxicity by comparing the toxicity of five strains of Prymnesium parvum toward rainbow trout (Oncorhynchus mykiss, 10 g) and the microalga Teleaulax acuta. No relationship between median effective concentrations (EC{sub 50}s) on fish and median lethal concentrations (LC{sub 50}s) on algae was observed in the 5 strains showing that a microalgal bioassay cannot be used as a proxy for ichthyotoxicity. Fish were more sensitive to P. parvum with EC{sub 50}s ranging from 6 × 10{sup 3} to 40 × 10{sup 3} cells ml{sup −1}, compared to the test alga where LC{sub 50}s ranged from 30 × 10{sup 3} to nearly non-toxic at 500 × 10{sup 3} cells ml{sup −1}. In addition, the cellular concentrations of two recently suggested ichthyotoxins produced by P. parvum, the “golden algae toxins”, GAT 512 and a novel GAT 510, did not show any relationship to either ichthyotoxicity or allelopathy, and are not the biologically relevant toxins, but are simply lipids found in algal chloroplasts. Finally, we demonstrate that the recently

A Spontaneous Joint Infection with Corynebacterium striatum▿

OpenAIRE

Scholle, David

2006-01-01

Corynebacterium striatum is a ubiquitous saprophyte with the potential to cause bacteremia in immunocompromised patients. Until now, spontaneous infection of a natural joint has not been reported. When phenotyping failed, gene sequencing was used to identify the species. The isolate demonstrated high-level resistance to most antibiotics.

Prymnesins: Toxic Metabolites of the Golden Alga, Prymnesium parvum Carter (Haptophyta

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John W. La Claire

2010-03-01

Full Text Available Increasingly over the past century, seasonal fish kills associated with toxic blooms of Prymnesium parvum have devastated aquaculture and native fish, shellfish, and mollusk populations worldwide. Protracted blooms of P. parvum can result in major disturbances to the local ecology and extensive monetary losses. Toxicity of this alga is attributed to a collection of compounds known as prymnesins, which exhibit potent cytotoxic, hemolytic, neurotoxic and ichthyotoxic effects. These secondary metabolites are especially damaging to gill-breathing organisms and they are believed to interact directly with plasma membranes, compromising integrity by permitting ion leakage. Several factors appear to function in the activation and potency of prymnesins including salinity, pH, ion availability, and growth phase. Prymnesins may function as defense compounds to prevent herbivory and some investigations suggest that they have allelopathic roles. Since the last extensive review was published, two prymnesins have been chemically characterized and ongoing investigations are aimed at the purification and analysis of numerous other toxic metabolites from this alga. More information is needed to unravel the mechanisms of prymnesin synthesis and the significance of these metabolites. Such work should greatly improve our limited understanding of the physiology and biochemistry of P. parvum and how to mitigate its blooms.

The Role of Progesterone and a Novel Progesterone Receptor, Progesterone Receptor Membrane Component 1, in the Inflammatory Response of Fetal Membranes to Ureaplasma parvum Infection.

Directory of Open Access Journals (Sweden)

Liping Feng

Full Text Available Ureaplasma parvum (U. parvum is gaining recognition as an important pathogen for chorioamnionitis and preterm premature rupture of membranes. We aimed to investigate the roles of progesterone (P4 and a novel progesterone receptor, progesterone receptor membrane component 1 (PGRMC1, in the response of fetal membranes to U. parvum. Fetal membrane cells (amnion, chorion and decidua were isolated and confirmed to be free of Mycoplasmataceae. Cells were treated with U. parvum (5x106 CFU, and adherence was quantified by qPCR. Amnion and chorion cells were transfected with scrambled siRNA or validated PGRMC1 siRNA for 72h. Cells were then treated with U. parvum for 4h with or without pretreatment with P4 (10-7 M or ethanol for 1h. Interleukin-8 (IL-8, matrix metalloproteinase 9 (MMP9 and cyclooxygenase (COX-2 mRNA expression were quantified by qRT-PCR. Culture medium was harvested and analyzed for IL-8 and prostaglandin (PGE2 secretion by ELISA and MMP9 activity by zymography. U. parvum had a mean adherence of 15.0±0.6%, 16.9± 3.7% and 4.7±0.3% in cultured amnion, chorion and decidua cells, respectively. Exposure to U. parvum elicited significant inflammatory responses including induction of IL-8, COX-2, PGE2 and MMP9. A possible role of PGRMC1 was identified in the inhibition of U. parvum-stimulated COX-2 and MMP9 mRNA expression in chorion cells and MMP9 activity in amnion cells. On the other hand, it might enhance the U. parvum-stimulated IL-8 protein secretion in amnion cells. P4, mediated through PGRMC1, significantly inhibited U. Parvum-induced MMP9 mRNA and COX-2 mRNA expression in chorion cells. P4 appeared to attenuate U. parvum induced IL-8 mRNA expression in chorion cells, but this P4 effect might not mediated through PGRMC1. In summary, U. parvum preferentially adheres to and induces inflammatory responses in chorion and amnion cells. P4 and PGRMC1 appear to differentially modulate the inflammatory responses induced by U. parvum among

Sigma factors and promoters in Corynebacterium glutamicum

Czech Academy of Sciences Publication Activity Database

Pátek, Miroslav; Nešvera, Jan

2011-01-01

Roč. 154, 2-3 (2011), s. 101-113 ISSN 0168-1656 R&D Projects: GA ČR GC204/09/J015 Institutional research plan: CEZ:AV0Z50200510 Keywords : Corynebacterium glutamicum * Sigma factors * Promoters Subject RIV: EE - Microbiology, Virology Impact factor: 3.045, year: 2011

Screening for Corynebacterium diphtheriae and Corynebacterium ulcerans in patients with upper respiratory tract infections 2007-2008: a multicentre European study.

LENUS (Irish Health Repository)

Wagner, K S

2011-04-01

Diphtheria is now rare in most European countries but, when cases do arise, the case fatality rate is high (5-10%). Because few countries continue to routinely screen for the causative organisms of diphtheria, the extent to which they are circulating amongst different European populations is largely unknown. During 2007-2008, ten European countries each screened between 968 and 8551 throat swabs from patients with upper respiratory tract infections. Six toxigenic strains of Corynebacterium diphtheriae were identified: two from symptomatic patients in Latvia (the country with the highest reported incidence of diphtheria in the European Union) and four from Lithuania (two cases, two carriers); the last reported case of diphtheria in Lithuania was in 2002. Carriage rates of non-toxigenic organisms ranged from 0 (Bulgaria, Finland, Greece, Ireland, Italy) to 4.0 per 1000 (95% CI 2.0-7.1) in Turkey. A total of 28 non-toxigenic strains were identified during the study (26 C. diphtheriae, one Corynebacterium ulcerans, one Corynebacterium pseudotuberculosis). The non-toxigenic C. ulcerans strain was isolated from the UK, the country with the highest reported incidence of cases due to C. ulcerans. Of the eleven ribotypes detected, Cluj was seen most frequently in the non-toxigenic isolates and, amongst toxigenic isolates, the major epidemic clone, Sankt-Petersburg, is still in circulation. Isolation of toxigenic C. diphtheriae and non-toxigenic C. diphtheriae and C. ulcerans in highly-vaccinated populations highlights the need to maintain microbiological surveillance, laboratory expertise and an awareness of these organisms amongst public health specialists, microbiologists and clinicians.

Corynebacterium macginleyi isolated from a corneal ulcer

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Kathryn Ruoff

2010-02-01

Full Text Available We report the isolation of Corynebacterium macginleyi from the corneal ulcer culture of a patient, later enrolled in the Steroids for Corneal Ulcer Trial (SCUT. To our knowledge this is the first published report from North America of the recovery of C. macginleyi from a serious ocular infection.

Comparison of antimicrobial susceptibilities of Corynebacterium species by broth microdilution and disk diffusion methods.

Science.gov (United States)

Weiss, K; Laverdière, M; Rivest, R

1996-01-01

Corynebacterium species are increasingly being implicated in foreign-body infections and in immunocompromised-host infections. However, there are no specific recommendations on the method or the criteria to use in order to determine the in vitro activities of the antibiotics commonly used to treat Corynebacterium infections. The first aim of our study was to compare the susceptibilities of various species of Corynebacterium to vancomycin, erythromycin, and penicillin by using a broth microdilution method and a disk diffusion method. Second, the activity of penicillin against our isolates was assessed by using the interpretative criteria recommended by the National Committee for Clinical Laboratory Standards for the determination of the susceptibility of streptococci and Listeria monocytogenes to penicillin. Overall, 100% of the isolates were susceptible to vancomycin, while considerable variations in the activities of erythromycin and penicillin were noted for the different species tested, including the non-Corynebacterium jeikeium species. A good correlation in the susceptibilities of vancomycin and erythromycin between the disk diffusion and the microdilution methods was observed. However, a 5% rate of major or very major errors was detected with the Listeria criteria, while a high rate of minor errors (18%) was noted when the streptococcus criteria were used. Our findings indicate considerable variations in the activities of erythromycin and penicillin against the various species of Corynebacterium. Because of the absence of definite recommendations, important discrepancies were observed between the methods and the interpretations of the penicillin activity. PMID:8849254

Molecular evidence of Ureaplasma urealyticum and Ureaplasma parvum colonization in preterm infants during respiratory distress syndrome

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Germani Rossella

2006-11-01

Full Text Available Abstract Background Ureaplasma urealyticum and U. parvum have been associated with respiratory diseases in premature newborns, but their role in the pathogenesis of the respiratory distress syndrome (RDS is unclear. The aim of this study was to detect, using molecular techniques, the role of Mycoplasma spp. and Ureaplasma spp. in respiratory secretion and blood specimens of preterm newborns with or without RDS and to evaluate the prevalence of perinatal U. urealyticum or U. parvum infection. The influence of chemotherapy on the clinical course was also evaluated. Methods Tracheal aspirate or nasopharingeal fluid samples from 50 preterm babies with (24 or without RDS (26 were analysed for detection of U. urealyticum and U. parvum by culture identification assay and PCR. Sequencing analysis of amplicons allowed us to verify the specificity of methods. Clarithromycin (10 mg kg-1 twice a day was administered in ureaplasma-positive patients who presented clinical signs of RDS. Results 15/24 neonates with RDS (p U. urealyticum or U. parvum. Culture identification assay was positive in 5/50 newborns, three of which with RDS. Sequencing analyses confirmed the specificity of these methods. Association of patent ductus arteriosus with ureaplasma colonization was more statistically significant (p = 0.0004 in patients with RDS than in those without RDS. Conclusion Colonization of the lower respiratory tract by Ureaplasma spp. and particularly by U. parvum in preterm newborns was related to RDS. The routine use of molecular methods could be useful to screen candidate babies for etiologic therapy.

Repeated maternal intramuscular or intraamniotic erythromycin incompletely resolves intrauterine Ureaplasma parvum infection in a sheep model of pregnancy.

Science.gov (United States)

Kemp, Matthew W; Miura, Yuichiro; Payne, Matthew S; Watts, Rory; Megharaj, Smruthi; Jobe, Alan H; Kallapur, Suhas G; Saito, Masatoshi; Spiller, O Brad; Keelan, Jeffrey A; Newnham, John P

2014-08-01

Ureaplasma spp are the most commonly isolated microorganisms in association with preterm birth. Maternal erythromycin administration is a standard treatment for preterm prelabor rupture of membranes. There is little evidence of its effectiveness in eradicating Ureaplasma spp from the intrauterine cavity and fetus. We used a sheep model of intrauterine Ureaplasma spp infection to investigate the efficacy of repeated maternal intramuscular and intraamniotic erythromycin treatment to eradicate such an infection. Thirty ewes with singleton pregnancies received an intraamniotic injection of 10(7) color change units of erythromycin-sensitive Ureaplasma parvum serovar 3 at 55 days' gestation. At 116 days' gestation, 28 ewes with viable fetuses were randomized to receive (1) intraamniotic and maternal intramuscular saline solution treatment (n = 8), (2) single intraamniotic and repeated maternal intramuscular erythromycin treatment (n = 10), or (3) single maternal intramuscular and repeated intraamniotic erythromycin treatment (n = 10). Fetuses were surgically delivered at 125 days' gestation. Treatment efficacy was assessed by culture, quantitative polymerase chain reaction, and histopathologic evaluation. Animals treated with intraamniotic erythromycin had significantly less viable U parvum serovar 3 in the amniotic fluid at delivery. However, neither combination of maternal intramuscular and intraamniotic erythromycin treatment successfully cleared U parvum serovar 3 from the amniotic fluid or fetal tissues. Three de novo erythromycin-resistant U parvum isolates were identified in erythromycin-treated animals. Erythromycin treatment, given both to the ewe and into the amniotic cavity, fails to eradicate intrauterine and fetal U parvum serovar 3 infection and may lead to development of erythromycin resistant U parvum. Copyright © 2014 Mosby, Inc. All rights reserved.

Statistical comparison of excystation methods in Cryptosporidium parvum oocysts

Czech Academy of Sciences Publication Activity Database

Pecková, R.; Stuart, P. D.; Sak, Bohumil; Květoňová, Dana; Kváč, Martin; Foitová, I.

2016-01-01

Roč. 230, OCT 30 (2016), s. 1-5 ISSN 0304-4017 R&D Projects: GA ČR(CZ) GAP505/11/1163 Institutional support: RVO:60077344 Keywords : Cryptosporidium parvum * excystation methods * in vitro cultivation * sodium hypochlorite * tlypsin Subject RIV: EG - Zoology Impact factor: 2.356, year: 2016

Isolation and Characterization of a Double Stranded DNA Megavirus Infecting the Toxin-Producing Haptophyte Prymnesium parvum

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Ben A. Wagstaff

2017-03-01

Full Text Available Prymnesium parvum is a toxin-producing haptophyte that causes harmful algal blooms globally, leading to large-scale fish kills that have severe ecological and economic implications. For the model haptophyte, Emiliania huxleyi, it has been shown that large dsDNA viruses play an important role in regulating blooms and therefore biogeochemical cycling, but much less work has been done looking at viruses that infect P. parvum, or the role that these viruses may play in regulating harmful algal blooms. In this study, we report the isolation and characterization of a lytic nucleo-cytoplasmic large DNA virus (NCLDV collected from the site of a harmful P. parvum bloom. In subsequent experiments, this virus was shown to infect cultures of Prymnesium sp. and showed phylogenetic similarity to the extended Megaviridae family of algal viruses.

Fate of Cryptosporidium parvum oocysts within soil, water, and plant environment.

Science.gov (United States)

McLaughlin, Stephen J; Kalita, Prasanta K; Kuhlenschmidt, Mark S

2013-12-15

Vegetative Filter Strips (VFS) have long been used to control the movement of agricultural nutrients and prevent them from reaching receiving waters. Earlier studies have shown that VFS also dramatically reduce both the kinetics and extent of Cryptosporidium parvum (C. parvum) oocysts overland transport. In this study, we investigated possible mechanisms responsible for the ability of VFS to reduce oocyst overland transport. Measurement of the kinetics of C. parvum adhesion to individual sand, silt, and clay soil particles revealed that oocysts associate over time, albeit relatively slow, with clay but not silt or sand particles. Measurement of oocyst overland transport kinetics, soil infiltration depth, distance of travel, and adhesion to vegetation on bare and vegetated soil surfaces indicate that oocysts move more slowly, and penetrate the soil profile to a greater extent on a vegetated surface than on a bare soil surface. Furthermore, we demonstrate a small fraction of the oocysts become attached to vegetation at the soil-vegetation interface on VFS. These results suggest VFS function to reduce oocyst overland transport by primarily decreasing oocyst surface flow enough to allow penetration within the soil profile followed by subsequent adhesion to or entrapment within clay particle aggregates, and to a lesser extent, adhesion to the surface vegetation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Colonization of the lower urogenital tract with Ureaplasma parvum can cause asymptomatic infection of the upper reproductive system in women: a preliminary study.

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Kasprzykowska, Urszula; Elias, Joanna; Elias, Marek; Mączyńska, Beata; Sobieszczańska, Beata Magdalena

2014-05-01

Genital ureaplasmas are considered opportunistic pathogens of human genitourinary tract involved in adverse pregnancy sequelae and infertility. While association of Ureaplasma urealyticum with urogenital tract infections is well established, the role of Ureaplasma parvum in these infections is still insufficient. In the study, we compared how often cervicovaginal colonization with U. parvum is associated with the presence of these microorganisms in the upper genitourinary tract of fertile and infertile women. We used PCR assay to determine the prevalence of U. parvum and U. urealyticum in pairs of specimens, i.e., vaginal swabs and Douglas' pouch fluid samples from consecutive 40 women with no symptoms of genital tract infection. In total, 19 (47.5 %) of the 40 samples were positive for ureaplasmas. U. parvum was simultaneously detected in pairs of samples in five (55.5 %) of the nine (47.4 %) women positive in PCR assay. As many as 5 (18.5 %) of the 27 infertile women and 1 (7.7 %) of the 13 fertile women showed infection of the upper genital tract with U. parvum. The results of the study demonstrated that colonization of the lower genital tract with U. parvum can produce asymptomatic infection of the upper reproductive system in women. These findings also imply that U. parvum may be present in the upper genital tract at the time of conception and might be involved in adverse pregnancy outcomes.

Long-Term Storage of Cryptosporidium parvum for In Vitro Culture

NARCIS (Netherlands)

Paziewska-Harris, A.; Schoone, G.; Schallig, H. D. F. H.

2018-01-01

The long-term storage of Cryptosporidium life-cycle stages is a prerequisite for in vitro culture of the parasite. Cryptosporidium parvum oocysts, sporozoites, and intracellular forms inside infected host cells were stored for 6-12 mo in liquid nitrogen utilizing different cryoprotectants (dimethyl

Identification of putative cis-regulatory elements in Cryptosporidium parvum by de novo pattern finding

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Kissinger Jessica C

2007-01-01

Full Text Available Abstract Background Cryptosporidium parvum is a unicellular eukaryote in the phylum Apicomplexa. It is an obligate intracellular parasite that causes diarrhea and is a significant AIDS-related pathogen. Cryptosporidium parvum is not amenable to long-term laboratory cultivation or classical molecular genetic analysis. The parasite exhibits a complex life cycle, a broad host range, and fundamental mechanisms of gene regulation remain unknown. We have used data from the recently sequenced genome of this organism to uncover clues about gene regulation in C. parvum. We have applied two pattern finding algorithms MEME and AlignACE to identify conserved, over-represented motifs in the 5' upstream regions of genes in C. parvum. To support our findings, we have established comparative real-time -PCR expression profiles for the groups of genes examined computationally. Results We find that groups of genes that share a function or belong to a common pathway share upstream motifs. Different motifs are conserved upstream of different groups of genes. Comparative real-time PCR studies show co-expression of genes within each group (in sub-sets during the life cycle of the parasite, suggesting co-regulation of these genes may be driven by the use of conserved upstream motifs. Conclusion This is one of the first attempts to characterize cis-regulatory elements in the absence of any previously characterized elements and with very limited expression data (seven genes only. Using de novo pattern finding algorithms, we have identified specific DNA motifs that are conserved upstream of genes belonging to the same metabolic pathway or gene family. We have demonstrated the co-expression of these genes (often in subsets using comparative real-time-PCR experiments thus establishing evidence for these conserved motifs as putative cis-regulatory elements. Given the lack of prior information concerning expression patterns and organization of promoters in C. parvum we

Interdigital foot infections: Corynebacterium minutissimum and agents of superficial mycoses

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Fatma Mutlu Sariguzel

2014-09-01

Full Text Available Interdigital foot infections are mostly caused initially by dermatophytes, yeasts and less frequently by bacteria. Erythrasma caused by Corynebacterium minutissimum can be confused with superficial mycoses. The aim of the study was to determine the prevalence of the etiologic agents of superficial mycoses and the frequency of Corynebacterium minutissimum in interdigital foot infections. All the samples obtained from the 121 patients with interdigital foot infections were examined directly with the use of 20% potassium hydroxide mounts and Gram stain under the microscope and cultured on Sabouraud's dextrose agar plates. In identification of superficial mycoses, the rate was found to be 14% with the cultural method and 14% with direct microscopic examination. Using a combination of direct microscopic examination and culture, a 33.8% ratio was achieved. In the culture of these samples, the most isolated factor was Trichophyton rubrum (33.7%. In 24 of the patients (19.8% Corynebacterium minutissimum was detected by Gram staining, in 6 of these patients Trichophyton rubrum was found, Trichophyton mentagrophytes was found in 2 and Trichosporon spp. was found in 1. The examination of interdigital foot lesions in the laboratory, the coexistence of erythrasma with dermatophytes and yeast should be considered.

Quantitative assessment of viable Cryptosporidium parvum load in commercial oysters (Crassostrea virginica) in the Chesapeake Bay.

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Graczyk, Thaddeus K; Lewis, Earl J; Glass, Gregory; Dasilva, Alexandre J; Tamang, Leena; Girouard, Autumn S; Curriero, Frank C

2007-01-01

The epidemiological importance of increasing reports worldwide on Cryptosporidium contamination of oysters remains unknown in relation to foodborne cryptosporidiosis. Thirty market-size oysters (Crassostrea virginica), collected from each of 53 commercial harvesting sites in Chesapeake Bay, MD, were quantitatively tested in groups of six for Cryptosporidium sp. oocysts by immunofluorescent antibody (IFA). After IFA analysis, the samples were retrospectively retested for viable Cryptosporidium parvum oocysts by combined fluorescent in situ hybridization (FISH) and IFA. The mean cumulative numbers of Cryptosporidium sp. oocysts in six oysters (overall, 42.1+/-4.1) were significantly higher than in the numbers of viable C. parvum oocysts (overall, 28.0+/-2.9). Of 265 oyster groups, 221 (83.4%) contained viable C. parvum oocysts, and overall, from 10-32% (mean, 23%) of the total viable oocysts were identified in the hemolymph as distinct from gill washings. The amount of viable C. parvum oocysts was not related to oyster size or to the level of fecal coliforms at the sampling site. This study demonstrated that, although oysters are frequently contaminated with oocysts, the levels of viable oocysts may be too low to cause infection in healthy individuals. FISH assay for identification can be retrospectively applied to properly stored samples.

Interactions between Cryptosporidium parvum and the Intestinal Ecosystem

KAUST Repository

Douvropoulou, Olga

2017-04-01

Cryptosporidium parvum is an apicomplexan protozoan parasite commonly causing diarrhea, particularly in infants in developing countries. The research challenges faced in the development of therapies against Cryptosporidium slow down the process of drug discovery. However, advancement of knowledge towards the interactions of the intestinal ecosystem and the parasite could provide alternative approaches to tackle the disease. Under this perspective, the primary focus of this work was to study interactions between Cryptosporidium parvum and the intestinal ecosystem in a mouse model. Mice were treated with antibiotics with different activity spectra and the resulted perturbation of the native gut microbiota was identified by microbiome studies. In particular, 16S amplicon sequencing and Whole Genome Sequencing (WGS) were used to determine the bacterial composition and the genetic repertoire of the fecal microbial communities in the mouse gut. Following alteration of the microbial communities of mice by application of antibiotic treatment, Cryptosporidium parasites were propagated in mice with perturbed microbiota and the severity of the infection was quantified. This approach enabled the prediction of the functional capacity of the microbial communities in the mouse gut and led to the identification of bacterial taxa that positively or negatively correlate in abundance with Cryptosporidium proliferation.

Effects of Ureaplasma parvum lipoprotein multiple-banded antigen on pregnancy outcome in mice.

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Uchida, Kaoru; Nakahira, Kumiko; Mimura, Kazuya; Shimizu, Takashi; De Seta, Francesco; Wakimoto, Tetsu; Kawai, Yasuhiro; Nomiyama, Makoto; Kuwano, Koichi; Guaschino, Secondo; Yanagihara, Itaru

2013-12-01

Ureaplasma spp. are members of the family Mycoplasmataceae and have been considered to be associated with chorioamnionitis and preterm delivery. However, it is unclear whether Ureaplasma spp. have virulence factors related to these manifestations. The purpose of the present study was to determine whether the immunogenic protein multiple-banded antigen (MBA) from Ureaplasma parvum is a virulence factor for preterm delivery. We partially purified MBA from a type strain and clinical isolates of U. parvum, and also synthesized a diacylated lipopeptide derived from U. parvum, UPM-1. Using luciferase assays, both MBA-rich fraction MRF and UPM-1 activated the NF-κB pathway via TLR2. UPM-1 upregulated IL-1β, IL-6, IL-12p35, TNF-α, MIP2, LIX, and iNOS in mouse peritoneal macrophage. MRF or UPM-1 was injected into uteri on day 15 of gestation on pregnant C3H/HeN mice. The intrauterine MRF injection group had a significantly higher incidence of intrauterine fetal death (IUFD; 38.5%) than the control group (14.0%). Interestingly, intrauterine injection of UPM-1 caused preterm deliveries at high concentration (80.0%). In contrast, a low concentration of UPM-1 induced a significantly higher rate of fetal deaths (55.2%) than the control group (14.0%). The placentas of the UPM-1 injection group showed neutrophil infiltration and increased iNOS protein expression. Our data indicate that MBA from the clinical isolate of U. parvum is a potential virulence factor for IUFD and preterm delivery in mice and that the N-terminal diacylated lipopeptide is essential for the initiation of inflammation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Different inflammatory responses are associated with Ureaplasma parvum-induced UTI and urolith formation.

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Reyes, Leticia; Reinhard, Mary; Brown, Mary B

2009-01-26

Epidemiologic studies show a strong association between Ureaplasmas and urogenital tract disease in humans. Since healthy humans can be colonized with Ureaplasmas, its role as a pathogen remains controversial. In order to begin to define the role of the host in disease, we developed a rodent model of urinary tract infection (UTI) using Fischer 344 (F344) rats. Animals were inoculated with sterile broth, 10(1), 10(3), 10(5), 10(7), or 10(9) log CFU of a rat-adapted strain of Ureaplasma parvum. Infected animals exhibited two distinct profiles, asymptomatic UTI and UTI complicated with struvite urolithiasis. Inoculum dose of U. parvum affected the incidence of UTI, and 50% to 57% of animals inoculated with >or= 10(7) CFU of U. parvum remained infected (p UTI was characterized by a minimal immune response that was predominantly monocytic and lymphocytic, with limited lesions, and elevated urinary levels of IFN-gamma, IL-18 and MCP-1 (P UTI complicated with struvite formation was characterized by an exaggerated immune response that was mostly neutrophilic (P UTI also had a significantly high rate of kidney infection (P UTI and disease.

Corynebacterium species causing breast abscesses among patients attending a tertiary care hospital in Chennai, South India.

Science.gov (United States)

Poojary, Indira; Kurian, Ann; V A, Jayalekshmi; Devapriya J, Debora; M A, Thirunarayan

2017-07-01

Corynebacterium species other than Corynebacterium diphtheriae were mostly considered contaminants in the past, but there are reports of their association with wide variety of human infections lately. In this study, we look into Corynebacterium species isolated from breast abscess patients and assess their antimicrobial susceptibility pattern and treatment outcomes. Pus samples from suspected breast abscess cases were examined from October 2014 to September 2015. Growth of Gram-positive bacilli morphologically resembling Corynebacterium species were identified by matrix-assisted laser desorption/ionization- time of flight mass spectrometry identifications generated by the Vitek MS system (bioMérieux, France) (MALDI-TOF Vitek MS system) and antimicrobial susceptibility was done. Corynebacterium species were isolated from 10 female breast abscess patients with median age of 36 years (range 25-59 years). Out of the 10 isolates four isolates were identified as C. kroppenstedtii; one isolate as C. striatum and five isolates were identified as C. amycolatum/C.xerosis. Out of four isolates of C .kroppenstedtii, two isolates were resistant to cotrimoxazole and one C. striatum isolate was resistant to penicillin, ampicillin, cotrimoxazole and clindamycin. Of the five isolates identified as C amycolatum/C xerosis, all were sensitive to vancomycin and linezolid but resistant to clindamycin. All the patients were treated with incision, drainage and antibiotics based on the sensitivity pattern; eight were cured and two patients did not come for follow-up. Corynebacterium species should be considered one of the causative agents of breast abscess and a varied susceptibility profile amongst the different species makes susceptibility testing important. Identification by MALDI-TOF Vitek MS system may not differentiate between C. amycolatum and C. xerosis.

Native valve endocarditis due to Corynebacterium group JK.

Science.gov (United States)

Moffie, B G; Veenendaal, R A; Thompson, J

1990-12-01

We report a case of a 32-yr-old woman on chronic intermittent haemodialysis, who developed endocarditis due to a Corynebacterium group JK, involving both the native aortic and mitral valves. Despite a four-week treatment with vancomycin, an aortic root abscess developed. The diagnosis was confirmed on autopsy.

Seven years' experience with Cryptosporidium parvum in Guinea-Bissau, West Africa

DEFF Research Database (Denmark)

Perch, M; Sodemann, Morten; Jakobsen, M S

2001-01-01

In community-based studies conducted from 1991 to 1997 in Guinea-Bissau, West Africa, stool specimens from children aged less than 5 years with diarrhoea were routinely examined for enteric parasites. Cryptosporidium parvum, found in 7.7% of 4,922 samples, was the second most common parasite......, exceeded only by Giardia lamblia which was found in 14.8% of the samples. The highest prevalence of cryptosporidium was found in children aged 6-11 months, whereas the prevalence of other enteric parasites increased with age. Cryptosporidiosis showed a marked seasonal variation, with peak prevalences found...... consistently at the beginning of or just before the rainy seasons, May through July. By contrast, no seasonality was found for the enteric parasites Giardia lamblia or Entamoeba histolytica. We conclude that Cryptosporidium parvum is an important pathogen in children with diarrhoea....

Effect of halofuginone lactate on the occurrence of Cryptosporidium parvum and growth of neonatal dairy calves.

Science.gov (United States)

Jarvie, B D; Trotz-Williams, L A; McKnight, D R; Leslie, K E; Wallace, M M; Todd, C G; Sharpe, P H; Peregrine, A S

2005-05-01

Thirty-one Holstein bull calves were purchased at birth from 3 dairy farms in Eastern Ontario. Each calf was assigned at random to oral treatment with either 5 mg of halofuginone lactate in 10.0 mL of aqueous carrier solution (Halocur, base comprised 10 mg of benzoic acid, 100 mg of lactic acid, and 0.3 mg of tartrazine) or 10 mL of placebo (Halocur base minus the active ingredient, halofuginone lactate) administered 15 to 30 min after morning milk feeding for the first 7 d of life. Intakes of milk, calf starter, and water, and fecal consistency score were recorded daily for 56 d. Calf weights were recorded weekly for 56 d. Fecal samples were taken from all calves at approximately 2, 7, 14, 21, and 28 d of age for isolation of Cryptosporidium parvum oocysts. Logistic and linear regression analyses were used to assess the effect of treatment on the incidence of diarrhea and C. parvum infection status. The odds of C. parvum shedding among calves in the halofuginone lactate-treated group was 70% lower than the odds of shedding among calves in the placebo group. In calves treated with halofuginone lactate, no oocyst shedding occurred until 2 wk of age, whereas 12.5% of calves in the placebo group began shedding oocysts during wk 1. From all ages of placebo-treated calves, 31 of 73 samples (42.5%) were positive for C. parvum, whereas only 15 of 67 samples (22.4%) from all ages of halofuginone lactate-treated calves tested positive. The largest number of C. parvum-positive samples occurred in the third week of life. There was a significant delay of 3.1 d in the incidence of diarrhea among calves treated with halofuginone lactate. Intake of milk and starter, body weight gains, and age at weaning were not significantly different between treatment groups.

Corynebacterium species: an uncommon agent of peritoneal dialysis-related peritonitis and a challenging treatment

OpenAIRE

Ferreira, Joel; Teixeira e Costa, Fernando; Ramos, Aura

2015-01-01

Introduction: Corynebacterium is a component of normal skin flora and it is responsible for an increasing incidence of nosocomial infections in the last decades. Peritonitis and exit-site infections caused by this microorganism are uncommon but have a significant clinical impact due to their high relapsing rate. The ideal therapeutic approach in these situations is not yet clearly defined. Methods: Retrospective analysis of Corynebacterium spp peritonitis in a peritoneal dialysis unit between...

Batch solar disinfection inactivates oocysts of Cryptosporidium parvum and cysts of Giardia muris in drinking water.

Science.gov (United States)

McGuigan, K G; Méndez-Hermida, F; Castro-Hermida, J A; Ares-Mazás, E; Kehoe, S C; Boyle, M; Sichel, C; Fernández-Ibáñez, P; Meyer, B P; Ramalingham, S; Meyer, E A

2006-08-01

To determine whether batch solar disinfection (SODIS) can be used to inactivate oocysts of Cryptosporidium parvum and cysts of Giardia muris in experimentally contaminated water. Suspensions of oocysts and cysts were exposed to simulated global solar irradiation of 830 W m(-2) for different exposure times at a constant temperature of 40 degrees C. Infectivity tests were carried out using CD-1 suckling mice in the Cryptosporidium experiments and newly weaned CD-1 mice in the Giardia experiments. Exposure times of > or =10 h (total optical dose c. 30 kJ) rendered C. parvum oocysts noninfective. Giardia muris cysts were rendered completely noninfective within 4 h (total optical dose >12 kJ). Scanning electron microscopy and viability (4',6-diamidino-2-phenylindole/propidium iodide fluorogenic dyes and excystation) studies on oocysts of C. parvum suggest that inactivation is caused by damage to the oocyst wall. Results show that cysts of G. muris and oocysts of C. parvum are rendered completely noninfective after batch SODIS exposures of 4 and 10 h (respectively) and is also likely to be effective against waterborne cysts of Giardia lamblia. These results demonstrate that SODIS is an appropriate household water treatment technology for use as an emergency intervention in aftermath of natural or man-made disasters against not only bacterial but also protozoan pathogens.

Fatal case of bacteremia caused by an atypical strain of Corynebacterium mucifaciens

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Vlademir Vicente Cantarelli

Full Text Available Corynebacterium species have often been considered normal skin flora or contaminants; however, in recent years they have been increasingly implicated in serious infections. Moreover, many new species have been discovered and old species renamed, especially after molecular biology techniques were introduced. Corynebacterium mucifaciens is mainly isolated from blood and from other normally-sterile body fluids; it forms slightly yellow, mucoid colonies on blood agar. We report a fatal case of bacteremia due to an atypical strain of C. mucifaciens. This strain had atypical colony morphology; analysis of the 16S rRNA gene was used to define the species.

In vitro inhibitory effects of plant-derived by-products against Cryptosporidium parvum

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Teichmann Klaus

2016-01-01

Full Text Available Disposal of organic plant wastes and by-products from the food or pharmaceutical industries usually involves high costs. In the present study, 42 samples derived from such by-products were screened in vitro against Cryptosporidium parvum, a protozoan parasite that may contaminate drinking water and cause diarrhoea. The novel bioassay was previously established in the microtitre plate format. Human ileocaecal adenocarcinoma (HCT-8 cell cultures were seeded with C. parvum oocysts and parasite development was monitored by an indirect fluorescent antibody technique (IFAT and microscopic assessment for clusters of secondary infection (CSI. Minimum inhibitory concentrations (MICs and potential detrimental effects on the host cells were determined. An ethanolic extract from olive (Olea europaea pomace, after oil pressing and phenol recovery, reproducibly inhibited C. parvum development (MIC = 250–500 μg mL−1, IC50 = 361 (279–438 μg mL−1, IC90 = 467 (398–615 μg mL−1. Accordingly, tyrosol, hydroxytyrosol, trans-coniferyl alcohol and oleuropein were selected as reference test compounds, but their contributions to the observed activity of the olive pomace extract were insignificant. The established test system proved to be a fast and efficient assay for identifying anti-cryptosporidial activities in biological waste material and comparison with selected reference compounds.

Inflammatory Response of Human Gestational Membranes to Ureaplasma parvum Using a Novel Dual-Chamber Tissue Explant System.

Science.gov (United States)

Potts, Lauren C; Feng, Liping; Seed, Patrick C; Jayes, Friederike L; Kuchibhatla, Maragatha; Antczak, Brian; Nazzal, Matthew K; Murtha, Amy P

2016-05-01

Preterm premature rupture of membranes (PPROM) is often associated with intra-amniotic inflammation and infection. Current understanding of the pathogenesis of PPROM includes activation of pro-inflammatory cytokines and proteolytic enzymes leading to compromise of membrane integrity. The impact of exposure to bacterial pathogens, including Ureaplasma parvum, on gestational membranes is poorly understood. Our objective was to develop a dual-chamber system to characterize the inflammatory response of gestational membranes to U. parvum in a directional nature. Full-thickness human gestational membrane explants, with either choriodecidua or amnion oriented superiorly, were suspended between two washers in a cylindrical device, creating two distinct compartments. Brilliant green dye was introduced into the top chamber to assess the integrity of the system. Tissue viability was evaluated after 72 h using a colorimetric cell proliferation assay. Choriodecidua or amnion was exposed to three doses of U. parvum and incubated for 24 h. Following treatment, media from each compartment were used for quantification of U. parvum (quantitative PCR), interleukin (IL)-8 (enzyme-linked immunosorbent assay), and matrix metalloproteinase (MMP)-2 and MMP-9 activity (zymography). We observed that system integrity and explant viability were maintained over 72 h. Dose-dependent increases in recovered U. parvum, IL-8 concentration, and MMP-2 activity were detected in both compartments. Significant differences in IL-8 concentration and MMP-9 activity were found between the choriodecidua and amnion. This tissue explant system can be used to investigate the inflammatory consequences of directional bacterial exposure for gestational membranes and provides insight into the pathogenesis of PPROM and infectious complications of pregnancy. © 2016 by the Society for the Study of Reproduction, Inc.

First description of Cryptosporidium parvum in carrier pigeons (Columba livia).

Science.gov (United States)

Oliveira, Bruno César Miranda; Ferrari, Elis Domingos; da Cruz Panegossi, Mariele Fernanda; Nakamura, Alex Akira; Corbucci, Flávio Sader; Nagata, Walter Bertequini; Dos Santos, Bianca Martins; Gomes, Jancarlo Ferreira; Meireles, Marcelo Vasconcelos; Widmer, Giovanni; Bresciani, Katia Denise Saraiva

2017-08-30

The carrier pigeon and the domestic pigeon are different breeds of the species Columba livia. Carrier pigeons are used for recreational activities such as bird contests and exhibitions. Due to the close contact with humans, these birds may potentially represent a public health risk, since they can host and disseminate zoonotic parasites, such as those belonging to the genus Cryptosporidium (phylum Apicomplexa). The purpose of this work was the detection by microscopic and molecular techniques of Cryptosporidium spp. oocysts in fecal samples of carrier pigeons, and subsequently to sequence the 18S ribosomal RNA marker of positive samples to identify the species. A total of 100 fecal samples were collected individually in two pigeon breeding facilities from Formiga and Araçatuba, cities located in Minas Gerais state and São Paulo state, Brazil, respectively. The age of the birds ranged from one to 12 years; 56 were females and 44 males. Fecal smears were stained with negative malachite green, whereas the molecular characterization was based on the sequence of a ∼800bp fragment of the 18S rRNA gene. Microscopic examination of fecal smears revealed 4% (4/100) oocyst positivity. On the other hand, 7% (7/100) of positivity were found using nested PCR. Three samples were 99% to 100% similar to Cryptosporidium parvum 18S rDNA type A (Genbank AH006572) and the other three samples had 99% to 100% similarity to C. parvum 18S rDNA type B (Genbank AF308600). To our knowledge, this is the first report of C. parvum oocysts in carrier pigeons. Copyright © 2017 Elsevier B.V. All rights reserved.

Isolamento de Corynebacterium aquaticum em leite bubalino

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Andréa Alice da Fonseca Oliveira

2005-08-01

Full Text Available Estudou-se 548 quartos mamários de búfalas, realizando-se exame clínico, CMT para detecção de mastite e coleta de amostras para isolamento bacteriano. Houve crescimento em duas amostras de Corynebacterium aquaticum caracterizadas bioquimicamente. Relata-se a participação do agente como colonizador do úbere e possível causador de mastites em bubalinos.

Alternate phase variation in expression of two major surface membrane proteins (MBA and UU376) of Ureaplasma parvum serovar 3.

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Zimmerman, Carl-Ulrich R; Stiedl, Thomas; Rosengarten, Renate; Spergser, Joachim

2009-03-01

Ureaplasma urealyticum and Ureaplasma parvum are commensals and pathogens of the human urogenital tract and of newborn infants. There are four distinct U. parvum serovars and 10 distinct U. urealyticum serovars. Both species possess a distinct immunodominant variable surface protein, the multiple banded antigen (MBA), which shows size variability among isolates as a result of changes in the number of C-terminal repeating units. Adjacent to the MBA gene (UU375) lies UU376, which was annotated as 'Ureaplasma-specific conserved hypothetical gene'. In four different strains of U. parvum serovar 3, we demonstrated expression of UU376 by Western blot analysis and phase variation between UU376, here designated Upvmp376 (Ureaplasma phase-variable membrane protein 376), and MBA after application of selective pressure with hyperimmune antisera directed against either protein. By Southern blot analysis, we found that the switch between MBA and Upvmp376 expression is associated with a DNA inversion event in which the nonrepetitive region of the MBA gene and its putative promoter region are opposed to either the repetitive region of MBA or UU376. We propose that in U. parvum serovar 3, and presumably in all U. parvum and U. urealyticum, an inversion event at specific sites effects an alternate ON/OFF switching of the genes UU375 and UU376.

A microbiological and clinical review on Corynebacterium kroppenstedtii

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Andreas Tauch

2016-07-01

Full Text Available The genus Corynebacterium represents a taxon of Gram-positive bacteria with a high G + C content in the genomic DNA. Corynebacterium kroppenstedtii is an unusual member of this taxon as it lacks the characteristic mycolic acids in the cell envelope. Genome sequence analysis of the C. kroppenstedtii type strain has revealed a lipophilic (lipid-requiring lifestyle and a remarkable repertoire of carbohydrate uptake and utilization systems. Clinical isolates of C. kroppenstedtii have been obtained almost exclusively from female patients and mainly from breast abscesses and cases of granulomatous mastitis. However, the role of C. kroppenstedtii in breast pathologies remains unclear. This review provides a comprehensive overview of the taxonomy, microbiology, and microbiological identification of C. kroppenstedtii, including polyphasic phenotypic approaches, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the use of 16S rRNA gene sequencing. A clinical review presents reported cases, various antimicrobial treatments, antibiotic susceptibility assays, and antibiotic resistance genes detected during genome sequencing. C. kroppenstedtii must be considered a potential opportunistic human pathogen and should be identified accurately in clinical laboratories.

The common vaginal commensal bacterium Ureaplasma parvum is associated with chorioamnionitis in extreme preterm labor.

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Cox, Ciara; Saxena, Nita; Watt, Alison P; Gannon, Caroline; McKenna, James P; Fairley, Derek J; Sweet, David; Shields, Michael D; L Cosby, Sara; Coyle, Peter V

2016-11-01

To assess the association of vaginal commensal and low-grade pathogenic bacteria including Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis, Mycoplasma genitalium, Group B streptococcus (GBS), and Gardnerella vaginalis, in women who delivered preterm at less than 37-week gestation in the presence or absence of inflammation of the chorioamnionitic membranes. A case control study involving women who delivered before 37-week gestation with and without inflammation of chorioamnionitic membranes. A total of 57 placental samples were histologically examined for polymorphonuclear leukocyte infiltration of placental tissue for evidence of chorioamnionitis, and by type-specific nucleic acid amplification for evidence of infection with one or more of the target bacteria. Demographic data were collected for each mother. Among the 57 placental samples, 42.1% had chorioamnionitis and 24.6% delivered in the second trimester of pregnancy; U. parvum, U. urealyticum, G. vaginalis, and GBS were all detected in the study with respective prevalence of 19.3%, 3.5%, 17.5%, and 15.8%; M. genitalium and M. hominis were not detected. U. parvum was significantly associated with chorioamnionitis (p = 0.02; OR 5.0; (95% CI 1.2-21.5) and was more common in women who delivered in the second (35.7%) compared to the third trimester of pregnancy (13.9%). None of the other bacteria were associated with chorioamnionitis or earlier delivery, and all G. vaginalis-positive women delivered in the third trimester of pregnancy (p = 0.04). The detection of U. parvum in placental tissue was significantly associated with acute chorioamnionitis in women presenting in extreme preterm labor.

An unusual case of chronic nonhealing periorbital ulceration due to a new species of Corynebacterium sp. strain UCL557

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Bipasa Chakraborty

2016-01-01

Full Text Available Nondiphtherial Corynebacterium (diphtheroids has been related to blood and wound infections but are an uncommon cause for soft tissue infection. We report a case of periorbital soft tissue infection with ulceration caused by multidrug-resistant Corynebacterium spp. in a 9-year-old girl who is apparently immunocompetant. Computed tomography scan showed soft tissue involvement of right periorbital region with no bony destructions or focal calcifications. Vision remained unaffected. Patient was treated by debridement and skin grafting, but condition did not improve. Pus collected from the periorbital ulcerated area was cultured in blood agar and Corynebacterium spp. was isolated from the pure culture, which was identified as a new species Corynebacterium sp. strain UCL557 using 16S rDNA- based molecular technique based on nucleotide homology and phylogenetic analysis. Antibiogram showed multiresistance pattern with sensitivity to ceftriaxone-sulbactum vancomycin and linezolid. After initiation of treatment with vancomycin infusion and oral linezolid, the patient responded well and lesion started to heal. To the best of our knowledge, this is the first ever case report of periorbital ulceration by new species of Corynebacterium sp. strain UCL557.

Differential recognition of the multiple banded antigen isoforms across Ureaplasma parvum and Ureaplasma urealyticum species by monoclonal antibodies.

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Aboklaish, Ali F; Ahmed, Shatha; McAllister, Douglas; Cassell, Gail; Zheng, Xiaotian T; Spiller, Owen B

2016-08-01

Two separate species of Ureaplasma have been identified that infect humans: Ureaplasma parvum and Ureaplasma urealyticum. Most notably, these bacteria lack a cell wall and are the leading infectious organism associated with infection-related induction of preterm birth. Fourteen separate representative prototype bacterial strains, called serovars, are largely differentiated by the sequence of repeating units in the C-terminus of the major surface protein: multiple-banded antigen (MBA). Monoclonal antibodies that recognise single or small groups of serovars have been previously reported, but these reagents remain sequestered in individual research laboratories. Here we characterise a panel of commercially available monoclonal antibodies raised against the MBA and describe the first monoclonal antibody that cross-reacts by immunoblot with all serovars of U. parvum and U. urealyticum species. We also describe a recombinant MBA expressed by Escherichia coli which facilitated further characterisation by immunoblot and demonstrate immunohistochemistry of paraffin-embedded antigens. Immunoblot reactivity was validated against well characterised previously published monoclonal antibodies and individual commercial antibodies were found to recognise all U. parvum strains, only serovars 3 and 14 or only serovars 1 and 6, or all strains belonging to U. parvum and U. urealyticum. MBA mass was highly variable between strains, consistent with variation in the number of C-terminal repeats between strains. Antibody characterisation will enable future investigations to correlate severity of pathogenicity to MBA isoform number or mass, in addition to development of antibody-based diagnostics that will detect infection by all Ureaplasma species or alternately be able to differentiate between U. parvum, U. urealyticum or mixed infections. Copyright © 2016 Elsevier B.V. All rights reserved.

Modulation of lipopolysaccharide-induced chorioamnionitis by Ureaplasma parvum in sheep.

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Snyder, Candice C; Wolfe, Katherine B; Gisslen, Tate; Knox, Christine L; Kemp, Matthew W; Kramer, Boris W; Newnham, John P; Jobe, Alan H; Kallapur, Suhas G

2013-05-01

Ureaplasma colonization in the setting of polymicrobial flora is common in women with chorioamnionitis, and is a risk factor for preterm delivery and neonatal morbidity. We hypothesized that Ureaplasma colonization of amniotic fluid would modulate chorioamnionitis induced by Escherichia coli lipopolysaccharide (LPS). Sheep received intraamniotic (IA) injections of media (control) or live Ureaplasma either 7 or 70 days before delivery. Another group received IA LPS 2 days before delivery. To test for interactions, U parvum-exposed animals were challenged with IA LPS, and delivered 2 days later. All animals were delivered preterm at 125 ± 1 day of gestation. Both IA Ureaplasma and LPS induced leukocyte infiltration of chorioamnion. LPS greatly increased the expression of proinflammatory cytokines and myeloperoxidase in leukocytes, while Ureaplasma alone caused modest responses. Interestingly, 7-day but not 70-day Ureaplasma exposure significantly down-regulated LPS-induced proinflammatory cytokines and myeloperoxidase expression in the chorioamnion. Acute (7-day) U parvum exposure can suppress LPS-induced chorioamnionitis. Copyright © 2013 Mosby, Inc. All rights reserved.

Chemodiversity of Ladder-Frame Prymnesin Polyethers in Prymnesium parvum

DEFF Research Database (Denmark)

Rasmussen, Silas Anselm; Meier, Sebastian; Andersen, Nikolaj Gedsted

2016-01-01

-HRMS) of 10 strains of P. parvum collected worldwide showed that only one strain produced the original prymnesin-1 and -2, whereas four strains produced the novel B-type prymnesin. In total 13 further prymnesin analogues differing in their core backbone and chlorination and glycosylation patterns could...

POTENSI GEN dtx DAN dtxR SEBAGAI MARKER UNTUK DETEKSI DAN PEMERIKSAAN TOKSIGENISITAS Corynebacterium diphtheriae

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Sunarno Sunarno

2013-05-01

Full Text Available Abstract.   Corynebacterium diphtheriae is the causative agent of diphtheria. The main virulence determinant of the bacteria is diphtheria toxin, the cause of the systemic complication seen with diphtheria. Production of diphtheria toxin by toxigenic strain encoded by dtx/tox gene and repressed by dtxR gene. Gold standard for bacterial toxigenicity test carried out by conventional methods (Elek test, Guinea pig and vero cell cytotoxicity. However, Elek test have variety result, time consume and problem of the reagent availability. On the other hand, the animal (Guinea pig testing was opposed by many animal lovers and the vero cell cytotoxicity test require high cost. The study purposed to evaluate the using of dtx and dtxR genes as a detection marker of C.diphtheriae and bacterial toxigenicity test simultaneusly by Multiplex PCR. The study examined 44 bacterial and fungal isolates, included 22 C.diphtheriae (4 reference strains and 18 clinical isolates, 5 other specieses of Corynebacterium  (reference strains and 17 non-Corynebacterium (10 reference strains and 7 stock cultures . All of sample were examined by Multiplex PCR for 2 primer pairs targeted dtx and dtxR genes. The study showed that the Multiplex PCR for dtx and dtxR as target genes able to detect all of sample correctly thus concluded that dtx and dtxR genes could be used as a marker for alternative detection and toxigenicity test of C.diphtheriae by Multiplex PCR rapidly and accuratelly. Key words: Corynebacterium diphtheriae, dtx, dan dtxR Abstrak. Corynebacterium diphtheriae merupakan agen penyebab penyakit difteri.. Faktor virulensi utama  C. diphtheriae adalah toksigenisitas (kemampuan memproduksi toksin bakteri toxin. Produksi toksin diatur seperangkat gen yang disebut gen tox/dtx dan diregulasi oleh gen dtxR. Gold standard untuk pemeriksaan toksigenisitas C.diphtheriae adalah dengan metode konvensional (Elek test, Guinea pig dan vero cell cytotoxigenicity,namun  Elek test

Cryptosporidium parvum and Cryptosporidium andersoni infection in naturally infected cattle of northwest Iran

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Yousef Mirzai

2014-04-01

Full Text Available The protozoan intestinal parasite Cryptosporidium commonly infects cattle throughout the world and Iran. The present study was undertaken to determine the abundance and associated risk factors of Cryptosporidium infection in cattle herds of northwestern Iran. A total number of 246 fecal samples from 138 (56.1% diarrheic (D and 108 (43.9% non-diarrheic (ND cattle were randomly collected and examined by fecal smears stained with Ziehl-Neelsen. For molecular specification, DNA was extracted from collected Cryptosporidium oocysts and a fragment of 1325 bp in size from 18S rRNA gene was amplified. The overall prevalence of Cryptosporidium infection was 22.3% (55/246. The prevalence of Cryptosporidium infection in examined calves less than 6 month-old was significantly higher than adult cattle. C. parvum and C. andersoni were identified in 20.3% (50/246 and 2.03% (5/246 of examined cattle, respectively. The highest prevalence of C. parvum infection was found in D calves < 6 month-old (13.4%, 33/246, while C. andersoni was only detected in ND cattle (8.9%, 22/246. There was significant difference in the prevalence between male than female cattle. There was no significant difference between prevalence and seasons of investigation. It was concluded that C. parvum was the prevalent species in younger animals compared to older ones as a potentially zoonotic agent in the region.

Biotin- and Glycoprotein-Coated Microspheres as Surrogates for Studying Filtration Removal of Cryptosporidium parvum in a Granular Limestone Aquifer Medium.

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Stevenson, M E; Blaschke, A P; Toze, S; Sidhu, J P S; Ahmed, W; van Driezum, I H; Sommer, R; Kirschner, A K T; Cervero-Aragó, S; Farnleitner, A H; Pang, L

2015-07-01

Members of the genus Cryptosporidium are waterborne protozoa of great health concern. Many studies have attempted to find appropriate surrogates for assessing Cryptosporidium filtration removal in porous media. In this study, we evaluated the filtration of Cryptosporidium parvum in granular limestone medium by the use of biotin- and glycoprotein-coated carboxylated polystyrene microspheres (CPMs) as surrogates. Column experiments were carried out with core material taken from a managed aquifer recharge site in Adelaide, Australia. For the experiments with injection of a single type of particle, we observed the total removal of the oocysts and glycoprotein-coated CPMs, a 4.6- to 6.3-log10 reduction of biotin-coated CPMs, and a 2.6-log10 reduction of unmodified CPMs. When two different types of particles were simultaneously injected, glycoprotein-coated CPMs showed a 5.3-log10 reduction, while the uncoated CPMs displayed a 3.7-log10 reduction, probably due to particle-particle interactions. Our results confirm that glycoprotein-coated CPMs are the most accurate surrogates for C. parvum; biotin-coated CPMs are slightly more conservative, while unmodified CPMs are markedly overly conservative for predicting C. parvum removal in granular limestone medium. The total removal of C. parvum observed in our study suggests that granular limestone medium is very effective for the filtration removal of C. parvum and could potentially be used for the pretreatment of drinking water and aquifer storage recovery of recycled water. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Early prosthetic valve endocarditis caused by Corynebacterium kroppenstedtii.

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Hagemann, Jürgen Benjamin; Essig, Andreas; Herrmann, Manuel; Liebold, Andreas; Quader, Mohamed Abo

2015-12-01

Corynebacterium (C.) kroppenstedtii is a rarely detected agent of bacterial infections in humans. Here, we describe the first case of prosthetic valve endocarditis caused by C. kroppenstedtii. Application of molecular methods using surgically excised valve tissue was a cornerstone for the establishment of the microbiological diagnosis, which is crucial for targeted antimicrobial treatment. Copyright © 2015 Elsevier GmbH. All rights reserved.

Urethritis due to corynebacterium striatum: An emerging germ.

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Frikh, Mohammed; El Yaagoubi, Imad; Lemnouer, Abdelhay; Elouennass, Mostafa

2015-01-01

Corynedbacterium striatum (CS) is a Gram-positive coryneform bacillus that is part of mucous and skin flora. It has been considered as a causative agent of many infections in intensive care, neurology, traumatology and urology, but was never implicated in non-gonococcal urethritis. We report the case of a nosocomial urethritis due to Corynebacterium striatum following resection of an intrameatus condyloma.

One-step simultaneous detection of Ureaplasma parvum and genotypes SV1, SV3 and SV6 from clinical samples using PlexPCR technology.

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Payne, M S; Furfaro, L L; Tucker, R; Tan, L Y; Mokany, E

2017-08-01

Ureaplasma spp. are associated with preterm birth. In recent times, it has become apparent that Ureaplasma parvum, but not Ureaplasma urealyticum, is of most relevance. We recently demonstrated this in Australian pregnant women and using high-resolution melt (HRM) PCR, further showed that U. parvum genotype SV6 was of particular significance. However, our assay was unable to identify multiple genotypes in the same sample, required a separate species-level qPCR for low titre samples and was not ideal for diagnostic laboratories due to the nature of HRM PCR result interpretation. Consequently, our current study developed a novel, one-step PlexPCR assay capable of detecting U. parvum and genotypes SV1, SV3 and SV6 in a single reaction directly from clinical samples. We then validated this using vaginal swab DNA from our Australian cohort of pregnant women. The PlexPCR was highly sensitive, detecting all targets to between 0.4 × 10 -5  ng DNA (SV3) and 0.4 × 10 -6  ng DNA (U. parvum, SV1 and SV6). Compared to our HRM PCR, the PlexPCR defined genotype distribution in all seven cases previously reported as 'mixed', and detected another eight cases where multiple genotypes (two) were present in samples previously reported as single genotypes using HRM PCR. Ureaplasma spp. have been associated with prematurity for decades, however, only a minority of studies have examined this beyond the genus level. In those that have, Ureaplasma parvum has been strongly associated with preterm birth. We recently demonstrated this in Australian women and further showed that U. parvum genotype SV6 was of particular significance. Our PlexPCR assay allows rapid detection and concurrent genotyping of U. parvum in clinical samples and may be of particular interest to obstetricians, particularly those caring for women at a high risk of preterm birth, and any other disease phenotypes where U. parvum is of interest. © 2017 The Authors. Letters in Applied Microbiology published by John

MOLECULAR CLONING AND ANALYSIS OF THE CRYPTOSPORIDIUM PARVUM AMINOPEPTIDASE N GENE. (R829180)

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Cryptosporidium parvum proteases have been associated with release of infective sporozoites from oocysts, and their specific inhibition blocks parasite excystation in vitro. Additionally, proteases have been implicated in the processing of parasite adhesion molecules fo...

MOLECULAR CLONING AND ANALYSIS OF THE CRYPTOSPORIDIUM PARVUM AMINOPEPTIDASE N GENE. (R828035)

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Cryptosporidium parvum proteases have been associated with release of infective sporozoites from oocysts, and their specific inhibition blocks parasite excystation in vitro. Additionally, proteases have been implicated in the processing of parasite adhesion molecules fo...

THE EFFICACY OF THREE MEDICINAL PLANTS: GARLIC, GINGER AND MIRAZID AND A CHEMICAL DRUG METRONIDAZOLE AGAINST CRYPTOSPORIDIUM PARVUM. I-IMMUNOLOGICAL RESPONSE.

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Abouel-Nour, Mohamed F; EL-Shewehy, Dina Magdy M; Hamada, Shadia F; Morsy, Tosson A

2015-12-01

Cryptosporidisis parvum is a zoonotic protozoan parasite infects intestinal epithelial cells causing a major health problem for man and animals. Experimentally the immunologic mediated elimination of C. parvum requires CD4+ T cells and IFN-gamma. But, the innate immune responses also have a significant protective role in both man and animals. the mucosal immune response to C. parvum in C57BL/6 neonatal and GKO mice shows a concomitant Thl and Th2 cytokine mRNA expression, with a crucial role for IFN-gamma in the resolution of the infection. NK cells and IFN-gamma have been shown to be important components in immunity in T and B cell-deficient mice, but IFN-gamma-dependent resistance is demonstrated in alymphocytic mice. Epithelial cells may play a vital role in immunity as once infected these cells have increased expression of inflammatory chemokines and cytokines and demonstrate anti-infection killing mechanisms. C. parvum immunological response was used to evaluate the efficacy of anti-cryptosporidisis agents of Garlic, Ginger, Mirazid and Metronidazole in experimentally infected mice.

Reassessing the ichthyotoxin profile of cultured Prymnesium parvum (golden algae) and comparing it to samples collected from recent freshwater bloom and fish kill events in North America.

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Henrikson, Jon C; Gharfeh, Majed S; Easton, Anne C; Easton, James D; Glenn, Karen L; Shadfan, Miriam; Mooberry, Susan L; Hambright, K David; Cichewicz, Robert H

2010-06-15

Within the last two decades, Prymnesium parvum (golden algae) has rapidly spread into inland waterways across the southern portion of North America and this organism has now appeared in more northerly distributed watersheds. In its wake, golden algae blooms have left an alarming trail of ecological devastation, namely massive fish kills, which are threatening the economic and recreational value of freshwater systems throughout the United States. To further understand the nature of this emerging crisis, our group investigated the chemical nature of the toxin(s) produced by P. parvum. We approached the problem using a two-pronged strategy that included analyzing both laboratory-grown golden algae and field-collected samples of P. parvum. Our results demonstrate that there is a striking difference in the toxin profiles for these two systems. An assemblage of potently ichthyotoxic fatty acids consisting primarily of stearidonic acid was identified in P. parvum cultures. While the concentration of the fatty acids alone was sufficient to account for the rapid-onset ichthyotoxic properties of cultured P. parvum, we also detected a second type of highly labile ichthyotoxic substance(s) in laboratory-grown golden algae that remains uncharacterized. In contrast, the amounts of stearidonic acid and its related congeners present in samples from recent bloom and fish kill sites fell well below the limits necessary to induce acute toxicity in fish. However, a highly labile ichthyotoxic substance, which is similar to the one found in laboratory-grown P. parvum cultures, was also detected. We propose that the uncharacterized labile metabolite produced by P. parvum is responsible for golden algae's devastating fish killing effects. Moreover, we have determined that the biologically-relevant ichthyotoxins produced by P. parvum are not the prymnesins as is widely believed. Our results suggest that further intensive efforts will be required to chemically define P. parvum

Experimental transmission of Corynebacterium pseudotuberculosis in horses by house flies

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The route of infection of pigeon fever remains undetermined. The purpose of this study was to investigate house flies (Musca domestica L.) as vectors of Corynebacterium pseudotuberculosis in horses. Eight ponies were used in a randomized, controlled, blinded experimental study. Ten wounds were creat...

Prevalência do Cryptosporidium parvum em crianças abaixo de 5 anos, residentes na zona urbana de Campo Grande, MS, Brasil, 1996

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Oshiro Elisa Teruya

2000-01-01

Full Text Available O presente estudo visou estabelecer a prevalência de Cryptosporidium parvum em crianças abaixo de 5 anos, residentes na zona urbana de Campo Grande, MS, 1996/97, através de exames coprológicos e avaliar epidemiologicamente os casos diagnosticados. Tratou-se de um estudo transversal com inquérito domiciliar, onde foram examinadas 1051 amostras fecais, processadas segundo a técnica de Blagg, utilizando-se a coloração de Ziehl-Neelsen modificada para a pesquisa de oocistos de C. parvum. Concluiu-se que: a prevalência de C. parvum (1,1% observada não foi estatisticamente significativa; foi relatado diarréia em 58,3% das crianças com diagnóstico positivo, supondo-se associação entre diarréia e a presença do parasita; o C. parvum foi mais freqüente em crianças com idade de 25 a 36 meses (50%, porém sem diferença estatisticamente significativa; o sexo não teve papel diferencial em relação ao parasitismo por C. parvum; entre as 12 crianças com criptosporidiose, 83,3% tiveram contato com animais domésticos (cão e ou gato.

Over-expression of NAD kinase in Corynebacterium crenatum and ...

African Journals Online (AJOL)

in Corynebacterium crenatum SYPA5-5 and to study its impact in presence of high (HOS) ... Results: In HOS condition, NAD+ kinase activity increased by 116 %, while ... (NADPH), an important co-enzyme during ... Polymerase, TaKaRa) using C. crenatum .... were washed with cold 100 mM PBS (pH 7.5) ..... Catalase and.

Oleylphosphocholine (OlPC) arrests Cryptosporidium parvum growth in vitro and prevents lethal infection in interferon gamma receptor knock-out mice.

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Sonzogni-Desautels, Karine; Renteria, Axel E; Camargo, Fabio V; Di Lenardo, Thomas Z; Mikhail, Alexandre; Arrowood, Michael J; Fortin, Anny; Ndao, Momar

2015-01-01

Cryptosporidium parvum is a species of protozoa that causes cryptosporidiosis, an intestinal disease affecting many mammals including humans. Typically, in healthy individuals, cryptosporidiosis is a self-limiting disease. However, C. parvum can cause a severe and persistent infection that can be life-threatening for immunocompromised individuals, such as AIDS patients. As there are no available treatments for these patients that can cure the disease, there is an urgent need to identify treatment options. We tested the anti-parasitic activity of the alkylphosphocholine oleylphosphocholine (OlPC), an analog of miltefosine, against C. parvum in in vitro and in vivo studies. In vitro experiments using C. parvum infected human ileocecal adenocarcinoma cells (HCT-8 cells) showed that OlPC has an EC50 of 18.84 nM. Moreover, no cell toxicity has been seen at concentrations ≤50 μM. C57BL/6 interferon gamma receptor knock-out mice, were infected by gavage with 4000 C. parvum oocysts on Day 0. Oral treatments, with OlPC, miltefosine, paromomycin or PBS, began on Day 3 post-infection for 10 days. Treatment with OlPC, at 40 mg/kg/day resulted in 100% survival, complete clearance of parasite in stools and a 99.9% parasite burden reduction in the intestines at Day 30. Doses of 30 and 20 mg/kg/day also demonstrated an increased survival rate and a dose-dependent parasite burden reduction. Mice treated with 10 mg/kg/day of miltefosine resulted in 50% survival at Day 30. In contrast, control mice, treated with PBS or 100 mg/kg/day of paromomycin, died or had to be euthanized between Days 6 and 13 due to severe illness. Results of parasite burden were obtained by qPCR and cross-validated by both flow cytometry of stool oocysts and histological sections of the ileum. Together, our results strongly support that OlPC represents a potential candidate for the treatment of C. parvum infections in immunocompromised patients.

Oleylphosphocholine (OlPC arrests Cryptosporidium parvum growth in vitro and prevents lethal infection in interferon gamma receptor knock-out mice

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Karine eSonzogni-Desautels

2015-09-01

Full Text Available Cryptosporidium parvum is a species of protozoa that causes cryptosporidiosis, an intestinal disease affecting many mammals including humans. Typically, in healthy individuals, cryptosporidiosis is a self-limiting disease. However, C. parvum can cause a severe and persistent infection that can be life-threatening for immunocompromised individuals, such as AIDS patients. As there are no available treatments for these patients that can cure the disease, there is an urgent need to identify treatment options. We tested the anti-parasitic activity of the alkylphosphocholine oleylphosphocholine (OlPC, an analog of miltefosine, against C. parvum in in vitro and in vivo studies. In vitro experiments using C. parvum infected human ileocecal adenocarcinoma cells (HCT-8 cells showed that OlPC has an EC50 of 18.84 nM. Moreover, no cell toxicity has been seen at concentrations ≤50 µM. C57BL/6 interferon gamma receptor knock-out mice, were infected by gavage with 4000 C. parvum oocysts on Day 0. Oral treatments, with OlPC, miltefosine, paromomycin or PBS, began on Day 3 post-infection for 10 days. Treatment with OlPC, at 40 mg/kg/day resulted in 100% survival, complete clearance of parasite in stools and a 99.9% parasite burden reduction in the intestines at Day 30. Doses of 30 mg/kg/day and 20 mg/kg/day also demonstrated an increased survival rate and a dose-dependent parasite burden reduction. Mice treated with 10 mg/kg/day of miltefosine resulted in 50% survival at Day 30. In contrast, control mice, treated with PBS or 100 mg/kg/day of paromomycin, died or had to be euthanized between Days 6 and 13 due to severe illness. Results of parasite burden were obtained by qPCR and cross-validated by both flow cytometry of stool oocysts and histological sections of the ileum. Together, our results strongly support that OlPC represents a potential candidate for the treatment of C. parvum infections in immunocompromised patients.

Physiological roles of sigma factor SigD in Corynebacterium glutamicum

Czech Academy of Sciences Publication Activity Database

Taniguchi, H.; Busche, T.; Patschkowski, T.; Niehaus, K.; Pátek, Miroslav; Kalinowski, J.; Wendisch, V.F.

2017-01-01

Roč. 17, č. 158 (2017), s. 158 ISSN 1471-2180 R&D Projects: GA ČR(CZ) GA17-06991S Institutional support: RVO:61388971 Keywords : Corynebacterium glutamicum * Sigma factor * SigD Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.644, year: 2016

Tools for genetic manipulations in Corynebacterium glutamicum and their applications

Czech Academy of Sciences Publication Activity Database

Nešvera, Jan; Pátek, Miroslav

2011-01-01

Roč. 90, č. 5 (2011), s. 1641-1654 ISSN 0175-7598 R&D Projects: GA ČR GC204/09/J015 Institutional research plan: CEZ:AV0Z50200510 Keywords : Corynebacterium glutamicum * Plasmid vectors * Promoters Subject RIV: EE - Microbiology, Virology Impact factor: 3.425, year: 2011

Cryptosporidium species and Cryptosporidium parvum subtypes in dairy calves and goat kids reared under traditional farming systems in Turkey.

Science.gov (United States)

Taylan-Ozkan, Aysegul; Yasa-Duru, Sibel; Usluca, Selma; Lysen, Colleen; Ye, Jianbin; Roellig, Dawn M; Feng, Yaoyu; Xiao, Lihua

2016-11-01

Molecular characterizations of Cryptosporidium spp. in ruminants reared under traditional animal management systems are scarce and studies conducted thus far have revealed largely an absence of the pathogenic and zoonotic species Cryptosporidium parvum in pre-weaned animals. In this study, we examined Cryptosporidium species and subtype distribution in free-range pre-weaned dairy calves and goat kids with diarrhea. Cryptosporidium-positive specimens from pre-weaned calves on 10 farms and goat kids on 4 farms in Ankara, Balikesir, Corum, Kirikkale, and Kirsehir Provinces, Turkey were genotyped by PCR-restriction length polymorphism analysis of the small subunit rRNA gene, which identified C. parvum in 27 calves and 9 goat kids and Cryptosporidium ryanae in 1 calf. Among the C. parvum isolates successfully subtyped by DNA sequence analysis of the 60 kDa glycoprotein gene, three subtypes were detected in calves, including IIaA13G2R1 (20/23), IIdA18G1 (2/23), and IIdA20G1b (1/23), and four subtypes were detected in goat kids, including IIaA13G2R1 (3/8), IIaA15G1R1 (2/8), IIdA22G1 (2/8), and IIdA18G1 (1/8). Data of the study suggest that dairy calves reared in a traditional cow-calf system in Turkey are mainly infected with a C. parvum subtype rarely seen elsewhere, whereas goat kids are infected with diverse subtypes. As all five C. parvum subtypes found in this study are known human pathogens, pre-weaned farm animals could play a potential role in the transmission of human cryptosporidiosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Pomegranate (Punica granatum) peel is effective in a murine model of experimental Cryptosporidium parvum.

Science.gov (United States)

Al-Mathal, Ebtisam M; Alsalem, Afaf M

2012-07-01

Cryptosporidiosis, a major health issue for neonatal calves, is caused by the parasite Cryptosporidium parvum, which is highly resistant to drug treatments. To date, many anti-parasitic drugs have been tested, but only a few have been shown to be partially effective in treating cryptosporidiosis. Previous studies have indicated that pomegranate (Punica granatum) possesses anti-plasmodium, anti-cestode, and anti-nematode activities. Therefore, the aim of this study was to evaluate the effect of P. granatum peel on suckling mice infected with experimental C. parvum. At 4days of age, 72 neonatal albino mice were randomly divided into five groups: G1: healthy controls, G2: infected/untreated controls, G3: uninfected/distilled water-treated, G4: uninfected/P. granatum peel-treated, and G5: infected/P. granatum peel-treated. Mice were experimentally-infected by oral administration of 1×10(3)C. parvum oocysts per animal. On day 7 post-inoculation (pi), treated mice received an aqueous suspension of P. granatum peel orally (3g/kg body weight). The presence of diarrhea, oocyst shedding, and weight gain/loss, and the histopathology of ileal sections were examined. Infected mice treated with the P. granatum peel suspension showed improvement in all parameters examined. Additionally, these mice did not exhibit any clinical symptoms and no deaths occurred. Oocyst shedding was very significantly reduced in the P. granatum-treated mice by day 14 pi (Pgranatum-treated mice was significantly higher than that of the infected/untreated controls throughout the study (Pgranatum-treated mice on day 14 pi showed visible improvement in comparison with the infected/untreated controls, including renewed brush borders, reduced numbers of C. parvum trophozoites, and reduced lymphatic infiltration. On day 28 pi, tissues of the P. granatum-treated mice were very similar to those of healthy control mice. These results suggest that P. granatum peel is a promising anti-coccidial therapeutic

Tips and tricks for the assembly of a Corynebacterium pseudotuberculosis genome using a semiconductor sequencer

DEFF Research Database (Denmark)

Ramos, Rommel Thiago Jucá; Carneiro, Adriana Ribeiro; Soares, Siomar de Castro

2013-01-01

that enable reference-based assembly, such as the one used in the present study, Corynebacterium pseudotuberculosis biovar equi, which causes high economic losses in the US equine industry. The quality treatment strategy incorporated into the assembly pipeline enabled a 16-fold greater use of the sequencing...... was validated by comparative genomics with other species of the genus Corynebacterium. The present study presents a modus operandi that enables a greater and better use of data obtained from semiconductor sequencing for obtaining the complete genome from a prokaryotic microorganism, C. pseudotuberculosis, which...

A RecET-assisted CRISPR-Cas9 genome editing in Corynebacterium glutamicum.

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Wang, Bo; Hu, Qitiao; Zhang, Yu; Shi, Ruilin; Chai, Xin; Liu, Zhe; Shang, Xiuling; Zhang, Yun; Wen, Tingyi

2018-04-23

Extensive modification of genome is an efficient manner to regulate the metabolic network for producing target metabolites or non-native products using Corynebacterium glutamicum as a cell factory. Genome editing approaches by means of homologous recombination and counter-selection markers are laborious and time consuming due to multiple round manipulations and low editing efficiencies. The current two-plasmid-based CRISPR-Cas9 editing methods generate false positives due to the potential instability of Cas9 on the plasmid, and require a high transformation efficiency for co-occurrence of two plasmids transformation. Here, we developed a RecET-assisted CRISPR-Cas9 genome editing method using a chromosome-borne Cas9-RecET and a single plasmid harboring sgRNA and repair templates. The inducible expression of chromosomal RecET promoted the frequencies of homologous recombination, and increased the efficiency for gene deletion. Due to the high transformation efficiency of a single plasmid, this method enabled 10- and 20-kb region deletion, 2.5-, 5.7- and 7.5-kb expression cassette insertion and precise site-specific mutation, suggesting a versatility of this method. Deletion of argR and farR regulators as well as site-directed mutation of argB and pgi genes generated the mutant capable of accumulating L-arginine, indicating the stability of chromosome-borne Cas9 for iterative genome editing. Using this method, the model-predicted target genes were modified to redirect metabolic flux towards 1,2-propanediol biosynthetic pathway. The final engineered strain produced 6.75 ± 0.46 g/L of 1,2-propanediol that is the highest titer reported in C. glutamicum. Furthermore, this method is available for Corynebacterium pekinense 1.563, suggesting its universal applicability in other Corynebacterium species. The RecET-assisted CRISPR-Cas9 genome editing method will facilitate engineering of metabolic networks for the synthesis of interested bio-based products from renewable

Transport and survival of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurry

DEFF Research Database (Denmark)

Petersen, Heidi H.; Enemark, Heidi; Olsen, Annette

The widespread waterborne pathogen Cryptosporidium parvum is frequently transmitted to humans via contaminated drinking and recreational water. Nearly all drinking water in Denmark is groundwater, which can be contaminated with oocysts e.g. from application of contaminated manure to the field...... in the leachates from soil columns to which Cryptosporidium positive slurry had been injected. Although recovery rates were low, regardless of slurry type, C. parvum oocysts were detected from all soil columns. Variations in the leachate patterns were recorded between soil columns added raw and liquid slurry...

Transport and survival of Cryptosporidium Parvum Oocysts in Soil Columns Following Applications of Raw and Separated Liquid Slurry

DEFF Research Database (Denmark)

Petersen, H.H.; Enemark, Heidi L.; Olsen, A.

The widespread waterborne pathogen Cryptosporidium parvum is primarily transmitted to humans via contaminated drinking and recreational water. Nearly all drinking water in Denmark is groundwater, but this can be contaminated with oocysts from application of contaminated manure to the field. Oocysts...... in the leachates from soil columns to which Cryptosporidium positive slurry had been injected. Although recovery rates were low, regardless of slurry type, C. parvum oocysts were detected from all soil columns. Variations in the leachate patterns were recorded between soil columns added raw and liquid slurry...

RNA-Seq analysis during the life cycle of Cryptosporidium parvum reveals significant differential gene expression between proliferating stages in the intestine and infectious sporozoites.

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Lippuner, Christoph; Ramakrishnan, Chandra; Basso, Walter U; Schmid, Marc W; Okoniewski, Michal; Smith, Nicholas C; Hässig, Michael; Deplazes, Peter; Hehl, Adrian B

2018-05-01

Cryptosporidium parvum is a major cause of diarrhoea in humans and animals. There are no vaccines and few drugs available to control C. parvum. In this study, we used RNA-Seq to compare gene expression in sporozoites and intracellular stages of C. parvum to identify genes likely to be important for successful completion of the parasite's life cycle and, thereby, possible targets for drugs or vaccines. We identified 3774 protein-encoding transcripts in C. parvum. Applying a stringent cut-off of eight fold for determination of differential expression, we identified 173 genes (26 coding for predicted secreted proteins) upregulated in sporozoites. On the other hand, expression of 1259 genes was upregulated in intestinal stages (merozoites/gamonts) with a gene ontology enrichment for 63 biological processes and upregulation of 117 genes in 23 metabolic pathways. There was no clear stage specificity of expression of AP2-domain containing transcription factors, although sporozoites had a relatively small repertoire of these important regulators. Our RNA-Seq analysis revealed a new calcium-dependent protein kinase, bringing the total number of known calcium-dependent protein kinases (CDPKs) in C. parvum to 11. One of these, CDPK1, was expressed in all stages, strengthening the notion that it is a valid drug target. By comparing parasites grown in vivo (which produce bona fide thick-walled oocysts) and in vitro (which are arrested in sexual development prior to oocyst generation) we were able to confirm that genes encoding oocyst wall proteins are expressed in gametocytes and that the proteins are stockpiled rather than generated de novo in zygotes. RNA-Seq analysis of C. parvum revealed genes expressed in a stage-specific manner and others whose expression is required at all stages of development. The functional significance of these can now be addressed through recent advances in transgenics for C. parvum, and may lead to the identification of viable drug and vaccine

Studies on the resistance/reactivation of Giardia muris cysts and Cryptosporidium parvum oocysts exposed to medium-pressure ultraviolet radiation.

Science.gov (United States)

Belosevic, M; Craik, S A; Stafford, J L; Neumann, N F; Kruithof, J; Smith, D W

2001-10-16

The ex vivo and in vivo reactivation of Giardia muris cysts and Cryptosporidium parvum oocysts after exposure to different doses of ultraviolet (UV) radiation was determined using animal infectivity. The infectivity of UV-treated parasites stored for 1-4 days (G. muris) or 1-17 days (C. parvum) at room temperature in the dark was similar to that of organisms administered immediately after UV treatment, indicating that the parasites did not reactivate ex vivo. In contrast, we observed in vivo reactivation of G. muris in three of seven independent animal infectivity experiments, when parasites were treated with relatively low doses of medium-pressure UV (muris cysts and C. parvum oocysts exposed to medium-pressure UV doses of 60 mJ/cm(2) or higher did not exhibit resistance to and/or reactivation following treatment. This suggests that when appropriate doses of UV are used, significant and permanent inactivation of these parasites may be achieved.

Random insertion and gene disruption via transposon mutagenesis of Ureaplasma parvum using a mini-transposon plasmid.

Science.gov (United States)

Aboklaish, Ali F; Dordet-Frisoni, Emilie; Citti, Christine; Toleman, Mark A; Glass, John I; Spiller, O Brad

2014-11-01

While transposon mutagenesis has been successfully used for Mycoplasma spp. to disrupt and determine non-essential genes, previous attempts with Ureaplasma spp. have been unsuccessful. Using a polyethylene glycol-transformation enhancing protocol, we were able to transform three separate serovars of Ureaplasma parvum with a Tn4001-based mini-transposon plasmid containing a gentamicin resistance selection marker. Despite the large degree of homology between Ureaplasma parvum and Ureaplasma urealyticum, all attempts to transform the latter in parallel failed, with the exception of a single clinical U. urealyticum isolate. PCR probing and sequencing were used to confirm transposon insertion into the bacterial genome and identify disrupted genes. Transformation of prototype serovar 3 consistently resulted in transfer only of sequence between the mini-transposon inverted repeats, but some strains showed additional sequence transfer. Transposon insertion occurred randomly in the genome resulting in unique disruption of genes UU047, UU390, UU440, UU450, UU520, UU526, UU582 for single clones from a panel of screened clones. An intergenic insertion between genes UU187 and UU188 was also characterised. Two phenotypic alterations were observed in the mutated strains: Disruption of a DEAD-box RNA helicase (UU582) altered growth kinetics, while the U. urealyticum strain lost resistance to serum attack coincident with disruption of gene UUR10_137 and loss of expression of a 41 kDa protein. Transposon mutagenesis was used successfully to insert single copies of a mini-transposon into the genome and disrupt genes leading to phenotypic changes in Ureaplasma parvum strains. This method can now be used to deliver exogenous genes for expression and determine essential genes for Ureaplasma parvum replication in culture and experimental models. Copyright © 2014 Elsevier GmbH. All rights reserved.

Detection of Cryptosporidium parvum and Cyclospora cayetanensis infections among people living in a slum area in Kathmandu valley, Nepal.

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Bhattachan, Balkrishna; Sherchand, Jeevan Bahadhur; Tandukar, Sarmila; Dhoubhadel, Bhim Gopal; Gauchan, Leesa; Rai, Ganesh

2017-09-07

The aim of this study is to determine the prevalence of Cyclospora cayetanensis and Cryptosporidium parvum infections among people living a slum in Kathmandu valley, Nepal. Ten different parasites were detected in the stool samples; the prevalence of any parasite was in 27.1% (71/262). The prevalence of C. cayetanensis and C. parvum were 14.1% (10/71) and 5.6% (4/71), respectively. This study showed high prevalence of intestinal parasitic infections along with the coccidian parasites in the slum area of Kathmandu Valley.

Patchoulol Production with Metabolically Engineered Corynebacterium glutamicum

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Nadja A. Henke

2018-04-01

Full Text Available Patchoulol is a sesquiterpene alcohol and an important natural product for the perfume industry. Corynebacterium glutamicum is the prominent host for the fermentative production of amino acids with an average annual production volume of ~6 million tons. Due to its robustness and well established large-scale fermentation, C. glutamicum has been engineered for the production of a number of value-added compounds including terpenoids. Both C40 and C50 carotenoids, including the industrially relevant astaxanthin, and short-chain terpenes such as the sesquiterpene valencene can be produced with this organism. In this study, systematic metabolic engineering enabled construction of a patchoulol producing C. glutamicum strain by applying the following strategies: (i construction of a farnesyl pyrophosphate-producing platform strain by combining genomic deletions with heterologous expression of ispA from Escherichia coli; (ii prevention of carotenoid-like byproduct formation; (iii overproduction of limiting enzymes from the 2-c-methyl-d-erythritol 4-phosphate (MEP-pathway to increase precursor supply; and (iv heterologous expression of the plant patchoulol synthase gene PcPS from Pogostemon cablin. Additionally, a proof of principle liter-scale fermentation with a two-phase organic overlay-culture medium system for terpenoid capture was performed. To the best of our knowledge, the patchoulol titers demonstrated here are the highest reported to date with up to 60 mg L−1 and volumetric productivities of up to 18 mg L−1 d−1.

BLIND TRIALS EVALUATING IN VITRO INFECTIVITY OF CRYPTOSPORIDIUM PARVUM OOCYSTS USING CELL CULTURE IMMUNOFLUORESCENCE

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An optimized cell culture-immunofluorescence (IFA) procedure, using the HCT-8 cell line, was evaluated in 'blind' trials to determine the sensitivity and reproducibility for measuring infectivity of flow cytometry prepared inocula of C. parvum oocysts. In separate trials, suspens...

Experimental transmission of Corynebacterium pseudotuberculosis biovar equi in horses by house flies

Science.gov (United States)

The route of Corynebacterium pseudotuberculosis infection in horses remains undetermined, but transmission by insects is suspected. Scientists from CMAVE and Auburn University investigated house flies (Musca domestica L.) as possible vectors. Three ponies were directly inoculated with C. pseudotuber...

Prevalence of Giardia sp. Cryptosporidium parvum and Cryptosporidium andersoni (syn. C. muris) [correction of Cryptosporidium parvum and Cryptosporidium muris (C. andersoni)] in 109 dairy herds in five counties of southeastern New York.

Science.gov (United States)

Wade, S E; Mohammed, H O; Schaaf, S L

2000-11-01

A cross-sectional study was undertaken to determine the prevalence of Giardia sp. (G. duodenalis group), Cryptosporidium parvum and Cryptosporidium andersoni (C. muris) [corrected] in dairy cattle in three different age groups, and to evaluate the association of age and season with prevalence. One hundred and nine dairy farms, from a total of 212 farms, in five counties of southeastern New York volunteered to participate. On these farms, 2943 fecal samples were collected from three defined age groups. The farms were randomly assigned for sampling within the four seasons of the year. Each farm was visited once during the study period from March 1993 to June 1994 to collect fecal samples. Demographic data on the study population was collected at the time of sampling by interviewing the farm owner or manager. At collection, fecal samples were scored as diarrheic or non-diarrheic, and each condition was later related to positive or negative infection with these parasites. Fecal samples were processed using a quantitative centrifugation concentration flotation technique and enumerated using bright field and phase contrast microscopy. In this study, the overall population prevalence for Giardia sp. was 8.9%; C. parvum, 0.9%; and C. muris, 1.1%. When considering animals most at the risk of infection (those younger than 6 months of age) Giardia sp. and C. parvum was found in 20.1 and 2.4% of the animals, respectively. Giardia sp. and C. muris were found in all age groups. There was no significant seasonal pattern of infection for any of these parasites.

Assessment of heavy metal tolerance and hexavalent chromium reducing potential of Corynebacterium paurometabolum SKPD 1204 isolated from chromite mine seepage

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Amal Kanti Paul

2016-07-01

Full Text Available Corynebacterium paurometabolum SKPD 1204 (MTCC 8730, a heavy metal tolerant and chromate reducing bacterium isolated from chromite mine seepage of Odisha, India has been evaluated for chromate reduction under batch culture. The isolate was found to tolerate metals like Co(II, Cu(II, Ni(II, Mn(II, Zn(II, Fe(III and Hg(II along with Cr(VI and was resistant to different antibiotics as evaluated by disc-diffusion method. The isolate, SKPD 1204 was found to reduce 62.5% of 2 mM Cr(VI in Vogel Bonner broth within 8 days of incubation. Chromate reduction capability of SKPD 1204 decreased with increase in Cr(VI concentration, but increased with increase in cell density and attained its maximum at 1010 cells/mL. Chromate reducing efficiency of SKPD 1204 was promoted in the presence of glycerol and glucose, while the highest reduction was recorded at pH 7.0 and 35 °C. The reduction process was inhibited by divalent cations Zn(II, Cd(II, Cu(II, and Ni(II, but not by Mn(II. Anions like nitrate, phosphate, sulphate and sulphite was found to be inhibitory to the process of Cr(VI reduction. Similarly, sodium fluoride, carbonyl cyanide m-chlorophenylhydrazone, sodium azide and N, N,-Di cyclohexyl carboiimide were inhibitory to chromate reduction, while 2,4-dinitrophenol appeared to be neither promotive nor inhibitory to the process.

Role of Wall Shear Stress in Cryptosporidium parvum Oocyst Attachment to Environmental Biofilms.

Science.gov (United States)

Luo, Xia; Jedlicka, Sabrina S; Jellison, Kristen L

2017-12-15

This study investigated Cryptosporidium parvum oocyst deposition onto biofilms as a function of shear stress under laminar or turbulent flow. Annular rotating bioreactors were used to grow stabilized stream biofilms at shear stresses ranging from 0.038 to 0.46 Pa. These steady-state biofilms were then used to assess the impact of hydrodynamic conditions on C. parvum oocyst attachment. C. parvum deposition onto biofilms followed a pseudo-second-order model under both laminar (after a lag phase) and turbulent flows. The total number of oocysts attached to the biofilm at steady state decreased as the hydrodynamic wall shear stress increased. The oocyst deposition rate constant increased with shear stress but decreased at high shear, suggesting that increasing wall shear stress results in faster attachment of Cryptosporidium due to higher mass transport until the shear forces exceed a critical limit that prevents oocyst attachment. These data show that oocyst attachment in the short and long term are impacted differently by shear: higher shear (to a certain limit) may be associated with faster initial oocyst attachment, but lower shear is associated with greater numbers of oocysts attached at equilibrium. IMPORTANCE This research provides experimental evidence to demonstrate that shear stress plays a critical role in protozoan-pathogen transport and deposition in environmental waters. The data presented in this work expand scientific understanding of Cryptosporidium attachment and fate, which will further influence the development of timely and accurate sampling strategies, as well as advanced water treatment technologies, to target protozoan pathogens in surface waters that serve as municipal drinking water sources. Copyright © 2017 American Society for Microbiology.

Candidatus Rickettsia andeanae, a spotted fever group agent infecting Amblyomma parvum ticks in two Brazilian biomes

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Fernanda Aparecida Nieri-Bastos

2014-04-01

Full Text Available Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul and from horses in the Cerrado biome (state of Piauí in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63 and 66.7% (2/3 of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB genes of Candidatus Rickettsia andeanae. This report is the first to describe Ca. R. andeanae in Brazil.

Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurry

DEFF Research Database (Denmark)

Petersen, Heidi Huus; Enemark, Heidi L.; Olsen, Annette

2012-01-01

to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether application of separated liquid slurry to agricultural land may represent higher risks for ground water contamination as compared to application of raw slurry.......The potential for transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a four week period......, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method although recovery rates were low (liquid slurry leached 73% and 90% more oocysts compared with columns with injected and surface applied raw slurry, respectively...

Metabolic engineering of an ATP-neutral Embden-Meyerhof-Parnas pathway in Corynebacterium glutamicum: growth restoration by an adaptive point mutation in NADH dehydrogenase.

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Komati Reddy, Gajendar; Lindner, Steffen N; Wendisch, Volker F

2015-03-01

Corynebacterium glutamicum uses the Embden-Meyerhof-Parnas pathway of glycolysis and gains 2 mol of ATP per mol of glucose by substrate-level phosphorylation (SLP). To engineer glycolysis without net ATP formation by SLP, endogenous phosphorylating NAD-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was replaced by nonphosphorylating NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (GapN) from Clostridium acetobutylicum, which irreversibly converts glyceraldehyde-3-phosphate (GAP) to 3-phosphoglycerate (3-PG) without generating ATP. As shown recently (S. Takeno, R. Murata, R. Kobayashi, S. Mitsuhashi, and M. Ikeda, Appl Environ Microbiol 76:7154-7160, 2010, http://dx.doi.org/10.1128/AEM.01464-10), this ATP-neutral, NADPH-generating glycolytic pathway did not allow for the growth of Corynebacterium glutamicum with glucose as the sole carbon source unless hitherto unknown suppressor mutations occurred; however, these mutations were not disclosed. In the present study, a suppressor mutation was identified, and it was shown that heterologous expression of udhA encoding soluble transhydrogenase from Escherichia coli partly restored growth, suggesting that growth was inhibited by NADPH accumulation. Moreover, genome sequence analysis of second-site suppressor mutants that were able to grow faster with glucose revealed a single point mutation in the gene of non-proton-pumping NADH:ubiquinone oxidoreductase (NDH-II) leading to the amino acid change D213G, which was shared by these suppressor mutants. Since related NDH-II enzymes accepting NADPH as the substrate possess asparagine or glutamine residues at this position, D213G, D213N, and D213Q variants of C. glutamicum NDH-II were constructed and were shown to oxidize NADPH in addition to NADH. Taking these findings together, ATP-neutral glycolysis by the replacement of endogenous NAD-dependent GAPDH with NADP-dependent GapN became possible via oxidation of NADPH formed in this pathway by mutant NADPH

Discovery of ebselen as an inhibitor of Cryptosporidium parvum glucose-6-phosphate isomerase (CpGPI by high-throughput screening of existing drugs

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Rana Eltahan

2018-04-01

Full Text Available Cryptosporidium parvum is a water-borne and food-borne apicomplexan pathogen. It is one of the top four diarrheal-causing pathogens in children under the age of five in developing countries, and an opportunistic pathogen in immunocompromised individuals. Unlike other apicomplexans, C. parvum lacks Kreb's cycle and cytochrome-based respiration, thus relying mainly on glycolysis to produce ATP. In this study, we characterized the primary biochemical features of the C. parvum glucose-6-phosphate isomerase (CpGPI and determined its Michaelis constant towards fructose-6-phosphate (Km = 0.309 mM, Vmax = 31.72 nmol/μg/min. We also discovered that ebselen, an organoselenium drug, was a selective inhibitor of CpGPI by high-throughput screening of 1200 known drugs. Ebselen acted on CpGPI as an allosteric noncompetitive inhibitor (IC50 = 8.33 μM; Ki = 36.33 μM, while complete inhibition of CpGPI activity was not achieved. Ebselen could also inhibit the growth of C. parvum in vitro (EC50 = 165 μM at concentrations nontoxic to host cells, albeit with a relatively small in vitro safety window of 4.2 (cytotoxicity TC50 on HCT-8 cells = 700 μM. Additionally, ebselen might also target other enzymes in the parasite, leading to the parasite growth reduction. Therefore, although ebselen is useful in studying the inhibition of CpGPI enzyme activity, further proof is needed to chemically and/or genetically validate CpGPI as a drug target. Keywords: Apicomplexan, Cryptosporidium parvum, Glucose-6-phosphate isomerase (GPI, Ebselen

Functional characterization of a vanillin dehydrogenase in Corynebacterium glutamicum

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Ding, Wei; Si, Meiru; Zhang, Weipeng; Zhang, Yaoling; Chen, Can; Zhang, Lei; Lu, Zhiqiang; Chen, Shaolin; Shen, Xihui

2015-01-01

Vanillin dehydrogenase (VDH) is a crucial enzyme involved in the degradation of lignin-derived aromatic compounds. Herein, the VDH from Corynebacterium glutamicum was characterized. The relative molecular mass (Mr) determined by SDS-PAGE was ~51kDa, whereas the apparent native Mr values revealed by gel filtration chromatography were 49.5, 92.3, 159.0 and 199.2kDa, indicating the presence of dimeric, trimeric and tetrameric forms. Moreover, the enzyme showed its highest level of activity toward vanillin at pH 7.0 and 30C, and interestingly, it could utilize NAD+ and NADP+ as coenzymes with similar efficiency and showed no obvious difference toward NAD+ and NADP+. In addition to vanillin, this enzyme exhibited catalytic activity toward a broad range of substrates, including p-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, o-phthaldialdehyde, cinnamaldehyde, syringaldehyde and benzaldehyde. Conserved catalytic residues or putative cofactor interactive sites were identified based on sequence alignment and comparison with previous studies, and the function of selected residues were verified by site-directed mutagenesis analysis. Finally, the vdh deletion mutant partially lost its ability to grow on vanillin, indicating the presence of alternative VDH(s) in Corynebacterium glutamicum. Taken together, this study contributes to understanding the VDH diversity from bacteria and the aromatic metabolism pathways in C. glutamicum. PMID:25622822

Comparative genomic analysis reveals occurrence of genetic recombination in virulent Cryptosporidium hominis subtypes and telomeric gene duplications in Cryptosporidium parvum.

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Guo, Yaqiong; Tang, Kevin; Rowe, Lori A; Li, Na; Roellig, Dawn M; Knipe, Kristine; Frace, Michael; Yang, Chunfu; Feng, Yaoyu; Xiao, Lihua

2015-04-18

Cryptosporidium hominis is a dominant species for human cryptosporidiosis. Within the species, IbA10G2 is the most virulent subtype responsible for all C. hominis-associated outbreaks in Europe and Australia, and is a dominant outbreak subtype in the United States. In recent yearsIaA28R4 is becoming a major new subtype in the United States. In this study, we sequenced the genomes of two field specimens from each of the two subtypes and conducted a comparative genomic analysis of the obtained sequences with those from the only fully sequenced Cryptosporidium parvum genome. Altogether, 8.59-9.05 Mb of Cryptosporidium sequences in 45-767 assembled contigs were obtained from the four specimens, representing 94.36-99.47% coverage of the expected genome. These genomes had complete synteny in gene organization and 96.86-97.0% and 99.72-99.83% nucleotide sequence similarities to the published genomes of C. parvum and C. hominis, respectively. Several major insertions and deletions were seen between C. hominis and C. parvum genomes, involving mostly members of multicopy gene families near telomeres. The four C. hominis genomes were highly similar to each other and divergent from the reference IaA25R3 genome in some highly polymorphic regions. Major sequence differences among the four specimens sequenced in this study were in the 5' and 3' ends of chromosome 6 and the gp60 region, largely the result of genetic recombination. The sequence similarity among specimens of the two dominant outbreak subtypes and genetic recombination in chromosome 6, especially around the putative virulence determinant gp60 region, suggest that genetic recombination plays a potential role in the emergence of hyper-transmissible C. hominis subtypes. The high sequence conservation between C. parvum and C. hominis genomes and significant differences in copy numbers of MEDLE family secreted proteins and insulinase-like proteases indicate that telomeric gene duplications could potentially contribute to

Immunolocalization of an enterotoxic glycoprotein exoantigen on the secretory organelles of Cryptosporidium parvum sporozoites

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El-Shewy K.A.

2004-06-01

Full Text Available In this study, the fine ultrastructures of the secretory organelles of C. parvum sporozoites were demonstrated using transmission electron microscopy (TEM. Meanwhile, a previously identified enterotoxic 18-20 kDa copro-antigen (18-20 kDa CCA, associated with cryptosporidiosis in both human and calves, was isolated and immunolocalized on C. parvum sporozoites. Using immunoelectron microscopy and anti-18-20 kDa monospecific antibody demonstrated marked existence of the 18-20 kDa CCA on the apical organelles and at the trilaminar pellicles. An anterior extrusion of this protein was demonstrated around the excysted and released sporozoites. However, non excysted sporozoites did not show this protein. Affinity blotting, with biotinylated jacalin, demonstrated the O-linked oligosaccharide moiety of this protein. The potential role of this protein in the host cell invasion and/or gliding motility remains unelucidated. However, its enterotoxicity, location and secretory nature suggest that it may be a target for neutralization or invasion inhibition of Cryptosporidium.

Stability of the intra- and extracellular toxins of Prymnesium parvum using a microalgal bioassay

DEFF Research Database (Denmark)

Blossom, Hannah Eva; Andersen, Nikolaj Gedsted; Rasmussen, Silas Anselm

2014-01-01

easily maintained. Reducing oxidation by storing the supernatant with no headspace in the vials significantly slowed loss of activity when stored at 4°C. We show that the lytic activity of the intracellular toxins, when released by sonication, is not as high as the extracellular toxins, however...... of P. parvum toxins before attempting to isolate and characterize them. The extracellular toxin in the supernatant is highly unstable, and it loses significant lytic effects after 3 days despite storage at −20°C and after only 24h stored at 4°C. However, when stored at −80°C, lytic activity is more...... the stability of the intracellular toxins when kept as a cell pellet at −20°C is excellent, which proves this is a sufficient storage method for less than 3 months. Our results provide an ecologically appropriate algal bioassay to quantify lytic activity of P. parvum toxins and we have advanced our knowledge...

Metabolomic profiling of faecal extracts from Cryptosporidium parvum infection in experimental mouse models.

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Josephine S Y Ng Hublin

Full Text Available Cryptosporidiosis is a gastrointestinal disease in humans and animals caused by infection with the protozoan parasite Cryptosporidium. In healthy individuals, the disease manifests mainly as acute self-limiting diarrhoea, but may be chronic and life threatening for those with compromised immune systems. Control and treatment of the disease is challenged by the lack of sensitive diagnostic tools and broad-spectrum chemotherapy. Metabolomics, or metabolite profiling, is an emerging field of study, which enables characterisation of the end products of regulatory processes in a biological system. Analysis of changes in metabolite patterns reflects changes in biochemical regulation, production and control, and may contribute to understanding the effects of Cryptosporidium infection in the host environment. In the present study, metabolomic analysis of faecal samples from experimentally infected mice was carried out to assess metabolite profiles pertaining to the infection. Gas-chromatography mass spectrometry (GC-MS carried out on faecal samples from a group of C. parvum infected mice and a group of uninfected control mice detected a mean total of 220 compounds. Multivariate analyses showed distinct differences between the profiles of C. parvum infected mice and uninfected control mice,identifying a total of 40 compounds, or metabolites that contributed most to the variance between the two groups. These metabolites consisted of amino acids (n = 17, carbohydrates (n = 8, lipids (n = 7, organic acids (n = 3 and other various metabolites (n = 5, which showed significant differences in levels of metabolite abundance between the infected and uninfected mice groups (p < 0.05. The metabolites detected in this study as well as the differences in abundance between the C. parvum infected and the uninfected control mice, highlights the effects of the infection on intestinal permeability and the fate of the metabolites as a result of nutrient scavenging by the

Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurries.

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Petersen, Heidi H; Enemark, Heidi L; Olsen, Annette; Amin, M G Mostofa; Dalsgaard, Anders

2012-09-01

The potential for the transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a 4-week period, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method, although recovery rates were low (vertical distribution of oocysts, with more oocysts recovered from soil columns added liquid slurry irrespective of the irrigation status. Further studies are needed to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether the application of separated liquid slurry to agricultural land may represent higher risks for groundwater contamination compared to application of raw slurry.

Corynebacterium striatum infecting a malignant cutaneous lesion: the emergence of an opportunistic pathogen Corynebacterium striatum infectando lesão cutânea maligna: a emergência de um patógeno oportunista

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Silvana Vargas Superti

2009-04-01

Full Text Available We described a case of a 27-year old male patient with skin and soft tissue infection of a neoplastic lesion caused by Corynebacterium striatum, an organism which has been rarely described as a human pathogen. Identification was confirmed by DNA sequencing. Successful treatment with penicillin was achieved. The role of the C. striatum as an emerging opportunistic pathogen is discussed.Descrevemos infecção de lesão neoplásica em paciente masculino de 27 anos, envolvendo pele e partes moles, causada por Corynebacterium striatum, um microrganismo raramente descrito como patógeno humano. A identificação foi confirmada por seqüenciamento de DNA. O paciente foi tratado com penicilina, com sucesso. O papel do C. striatum como patógeno oportunista é discutido.

Complete genome sequence of Corynebacterium pseudotuberculosis Cp31, isolated from an Egyptian buffalo

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Silva, Artur; Ramos, Rommel Thiago Jucá; Ribeiro Carneiro, Adriana

2012-01-01

Corynebacterium pseudotuberculosis is of major veterinary importance because it affects many animal species, causing economically significant livestock diseases and losses. Therefore, the genomic sequencing of various lines of this organism, isolated from different hosts, will aid in the developm...

Rapid PCR Detection of Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum

OpenAIRE

Scott A. Cunningham; Jayawant N. Mandrekar; Jon E. Rosenblatt; Robin Patel

2013-01-01

Objective. We compared laboratory developed real-time PCR assays for detection of Mycoplasma hominis and for detection and differentiation of Ureaplasma urealyticum and parvum to culture using genitourinary specimens submitted for M. hominis and Ureaplasma culture. Methods. 283 genitourinary specimens received in the clinical bacteriology laboratory for M. hominis and Ureaplasma species culture were evaluated. Nucleic acids were extracted using the Total Nucleic Acid Kit on the MagNA Pure 2.0...

Trans-suppression of host CDH3 and LOXL4 genes during Cryptosporidium parvum infection involves nuclear delivery of parasite Cdg7_FLc_1000 RNA.

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Ming, Zhenping; Gong, Ai-Yu; Wang, Yang; Zhang, Xin-Tian; Li, Min; Li, Yao; Pang, Jing; Dong, Stephanie; Strauss-Soukup, Juliane K; Chen, Xian-Ming

2018-05-01

Intestinal infection by Cryptosporidium parvum causes significant alterations in the gene expression profile in host epithelial cells. Previous studies demonstrate that a panel of parasite RNA transcripts of low protein-coding potential are delivered into infected host cells and may modulate host gene transcription. Using in vitro models of human intestinal cryptosporidiosis, we report here that trans-suppression of the cadherin 3 (CDH3) and lysyl oxidase like 4 (LOXL4) genes in human intestinal epithelial cells following C. parvum infection involves host delivery of the Cdg7_FLc_1000 RNA, a C. parvum RNA that has been previously demonstrated to be delivered into the nuclei of infected host cells. Downregulation of CDH3 and LOXL4 genes was detected in host epithelial cells following C. parvum infection or in cells expressing the parasite Cdg7_FLc_1000 RNA. Knockdown of Cdg7_FLc_1000 attenuated the trans-suppression of CDH3 and LOXL4 genes in host cells induced by infection. Interestingly, Cdg7_FLc_1000 was detected to be recruited to the promoter regions of both CDH3 and LOXL4 gene loci in host cells following C. parvum infection. Host delivery of Cdg7_FLc_1000 promoted the PH domain zinc finger protein 1 (PRDM1)-mediated H3K9 methylation associated with trans-suppression in the CDH3 gene locus, but not the LOXL4 gene. Therefore, our data suggest that host delivery of Cdg7_FLc_1000 causes CDH3 trans-suppression in human intestinal epithelial cells following C. parvum infection through PRDM1-mediated H3K9 methylation in the CDH3 gene locus, whereas Cdg7_FLc_1000 induces trans-suppression of the host LOXL4 gene through H3K9/H3K27 methylation-independent mechanisms. Copyright © 2018 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

An unusual etiological agent of implantable cardioverter device endocarditis: Corynebacterium mucifaciens

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Adnan Kaya

2016-03-01

Full Text Available Cardiac pacing devices and implantable cardioverter defibrillator (ICD are becoming the mainstay of therapy in cardiology and infective endocarditis (IE and pocket infection; however, these devices require careful monitoring. Here, we describe a case of a 68-year-old female with an ICD presenting with a previously unknown etiological agent of IE, Corynebacterium mucifaciens.

Seroprevalence of Cryptosporidium parvum infection of dairy cows in three northern provinces of Thailand determined by enzyme-linked immunosorbent assay using recombinant antigen CpP23.

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Inpankaew, T; Jittapalapong, S; Phasuk, J; Pinyopanuwut, N; Chimnoi, W; Kengradomkit, C; Sunanta, C; Zhang, G; Aboge, G O; Nishikawa, Y; Igarashi, I; Xuan, X

2009-06-01

Cryptosporidium parvum is the most frequent parasitic agent that causes diarrhoea in AIDS patients in Thailand. Cryptosporidiosis outbreaks in humans may be attributed to contamination of their drinking water from infected dairy pastures. A 23-kDa glycoprotein of C. parvum (CpP23) is a sporozoite surface protein that is geographically conserved among C. parvum isolates. This glycoprotein is a potentially useful candidate antigen for the diagnosis of cryptosporidiosis by enzyme-linked immunosorbent assay. Therefore, we investigated the seroprevalence of C. parvum infection in dairy cows in northern Thailand using an ELISA based on recombinant CpP23 antigen. Sera were randomly collected from 642 dairy cows of 42 small-holder farmers, which had the top three highest number of the dairy cows' population in Northern Thailand, that included Chiang Mai, Chiang Rai and Lumpang provinces. The overall seroprevalence of the infection was 4.4%, and the seropositive rates for the three provinces were 3.3% in Chiang Mai, 5.1% in Chiang Rai and 3% in Lumpang. These results suggest that cattle could play a role in zoonotic cryptosporidiosis in Thailand.

Trans-suppression of defense DEFB1 gene in intestinal epithelial cells following Cryptosporidium parvum infection is associated with host delivery of parasite Cdg7_FLc_1000 RNA.

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Ming, Zhenping; Gong, Ai-Yu; Wang, Yang; Zhang, Xin-Tian; Li, Min; Dolata, Courtney E; Chen, Xian-Ming

2018-03-01

To counteract host immunity, Cryptosporidium parvum has evolved multiple strategies to suppress host antimicrobial defense. One such strategy is to reduce the production of the antimicrobial peptide beta-defensin 1 (DEFB1) by host epithelial cells but the underlying mechanisms remain unclear. Recent studies demonstrate that a panel of parasite RNA transcripts of low protein-coding potential are delivered into infected host cells and may modulate host gene transcription. Using in vitro models of intestinal cryptosporidiosis, in this study, we analyzed the expression profile of host beta-defensin genes in host cells following infection. We found that C. parvum infection caused a significant downregulation of the DEFB1 gene. Interestingly, downregulation of DEFB1 gene was associated with host delivery of Cdg7_FLc_1000 RNA transcript, a C. parvum RNA that has previously demonstrated to be delivered into the nuclei of infected host cells. Knockdown of Cdg7_FLc_1000 in host cells could attenuate the trans-suppression of host DEFB1 gene and decreased the parasite burden. Therefore, our data suggest that trans-suppression of DEFB1 gene in intestinal epithelial cells following C. parvum infection involves host delivery of parasite Cdg7_FLc_1000 RNA, a process that may be relevant to the epithelial defense evasion by C. parvum at the early stage of infection.

Characterization of an Immunogenic Glycocalyx on the Surfaces of Cryptosporidium parvum Oocysts and Sporozoites

OpenAIRE

Nanduri, Jayasri; Williams, Selvi; Aji, Toshiki; Flanigan, Timothy P.

1999-01-01

Ruthenium red staining of Cryptosporidium parvum oocysts revealed the presence of a carbohydrate matrix on their outer bilayers that is characteristic of a glycocalyx. Surface labeling of intact oocysts identified material of high molecular weight (>106) that reacted positively with sera from cryptosporidium-infected patients and with immunoglobulin A monoclonal antibodies.

Co-infections with Ureaplasma parvum, Mycoplasma hominis and Chlamydia trachomatis in a human immunodeficiency virus positive woman with vaginal discharge.

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Ghosh, Arnab; Rawre, Jyoti; Khanna, Neena; Dhawan, Benu

2013-01-01

A 30-year-old human immunodeficiency virus (HIV)-1 infected woman presented with vaginal discharge and associated vulval irritation. The vaginal swabs tested positive for Ureaplasma parvum and Mycoplasma hominis by both culture and polymerase chain reaction (PCR). The specimen also tested positive for Chlamydia trachomatis deoxyribonucleic acid (DNA) by cryptic plasmid and omp1 gene PCR assays. The patient was successfully treated with azithromycin based on the antibiotic susceptibility testing results of U. parvum and M. hominis by microbroth dilution. Since sexually transmitted infections enhance the transmission of HIV, HIV-positive patients should be screened routinely for these pathogens.

Neofusicoccum eucalyptorum (=Botryosphaeria eucalyptorum Y N. parvum: PATÓGENOS EN PLANTACIONES DE EUCALIPTO EN MÉXICO

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Jesús G. De la Mora-Castañeda

2014-01-01

Full Text Available En el oriente de Michoacán, la muerte regresiva en plantaciones comerciales de eucalipto se presentó en árboles con daños por heladas y sequías en el 2013. En Eucalyptus nitens se aisló al patógeno Neofusicoccum eucalyptorum encontrando a su teleomorfo Botryosphaeria eucalypto - rum en los cancros, mientras que N. parvum se aisló de E. nitens y E. globulus. Ambas especies de Neofusicoccum se identificaron por morfología y se caracterizaron molecularmente mediante PCR- ITS. Las secuencias de N. eucalyptorum (números de acceso: KC479184 y KC4799188 y N. parvum (KC479185, KC479186 y KC479187 se depositaron en el Banco de Genes del NCBI. En campo, los eucaliptos enfermos presentaron muerte regresiva, cancros fusiformes en fuste que inducen hincha - mientos, flujo de resina y brotes epicórmicos. Los hongos inoculados in vitro en varetas de E. nitens y E. globulus causaron lesiones necróticas y abundantes picnidios inmaduros a 10 días después de la inocu - lación (ddi. En los árboles de E. nitens de tres años de edad se formó un cancro de apariencia hundida con forma fusiforme, de color café oscuro y de 13 a 21.9 cm a los 48 ddi. Este trabajo es el primer reporte de N. eucalyptorum y N. parvum en México causando enfermedad en plantaciones de eucalipto.

Growth and extracellular laccase production in liquid cultures of Minimidochium parvum LPSC # 548 Strain Crecimiento y producción de lacasa extracelular en cultivos líquidos de Minimidochium parvum cepa LPSC # 548

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Mario C. N. Saparrat

2007-07-01

Full Text Available Minimidochium parvum LPSC # 548, a fungus isolated from litter floating on waters of Río Santiago (Provincia de Buenos Aires, Argentina polluted with industrial effluents and crude-oil, was grown as a shaking culture on a C-limited medium to evaluate its ability to produce extracellular laccase. The effect of anthracene, CuSO4 · 5H2O, ethanol, guaiacol, humic acids, Kraft lignin, MnSO4· H2O, Tween 20 and veratryl alcohol on its growth and extracellular laccase activity levels was also analyzed. The cultures grown on basal medium produced maximum biomass (over 420 mg/100 ml and maximum extracellular laccase activity (351.7 ±53.3 pkat/ml after 5 days of incubation. Among the different factors tested, only the humic acids at 0.1 % (w/v were found to stimulate the growth of M. parvum . However, Tween 20 (0.1 %, v/v was the only one that produced an increase of laccase activity levels up to 2.5-fold compared to the control.Minimidochium parvum LPSC # 548, un hongo aislado de materia orgánica colectada en aguas de Río Santiago (Provincia de Buenos Aires, Argentina contaminadas con efluentes industriales y crudo de petróleo, se cultivó en un medio líquido limitante en carbono bajo agitación para evaluar su habilidad para producir lacasa extracelular. Se analizó también el efecto de ácidos húmicos, alcohol veratrílico, antraceno, CuSO4 · 5H2O, etanol, guaiacol, lignina Kraft, MnSO4· H2O y Tween 20 sobre el crecimiento fúngico y los niveles de actividad lacasa extracelular. Los cultivos sobre medio basal produjeron máximos niveles de biomasa (superior a 420 mg/100 ml y actividad lacasa extracelular (351,7 ±53,3 pkat/ml después de 5 días de incubación. Entre los diferentes agentes químicos testeados, sólo los ácidos húmicos al 0,1 % (p/v estimularon el crecimiento de M. parvum . No obstante, sólo el Tween 20 (0,1 %, v/v produjo un incremento de los niveles de actividad lacasa (2,5 veces comparado a cultivos control.

Source water assessment and nonpoint sources of acutely toxic contaminants: A review of research related to survival and transport of Cryptosporidium parvum

Science.gov (United States)

Walker, Mark J.; Montemagno, Carlo D.; Jenkins, Michael B.

1998-12-01

Amendments to the Safe Drinking Water Act (PL-930123) in 1996 required that public water supply managers identify potential sources of contamination within contributing areas. Nonpoint sources of acutely toxic microbial contaminants, such as Cryptosporidium parvum, challenge current approaches to source identification and management as a first step toward developing management plans for public water supply protection. Little may be known about survival and transport in the field environment, prescribed practices may not be designed to manage such substances, and infective stages may be present in vast numbers and may resist water treatment and disinfection processes. This review summarizes research related to survival and transport of C. parvum oocysts, as an example of an acutely toxic contaminant with nonpoint sources in animal agriculture. It discusses ∥1) significance of infected domesticated animals as potential sources of C. parvum, (2) laboratory and field studies of survival and transport, and (3) approaches to source control in the context of public health protection.

Ureaplasma parvum serovar 3 multiple banded antigen size variation after chronic intra-amniotic infection/colonization.

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Robinson, James W; Dando, Samantha J; Nitsos, Ilias; Newnham, John; Polglase, Graeme R; Kallapur, Suhas G; Pillow, J Jane; Kramer, Boris W; Jobe, Alan H; Payton, Diane; Knox, Christine L

2013-01-01

Ureaplasma species are the microorganisms most frequently associated with adverse pregnancy outcomes. The multiple banded antigen (MBA), a surface-exposed lipoprotein, is a key virulence factor of ureaplasmas. The MBA demonstrates size variation, which we have shown previously to be correlated with the severity of chorioamnion inflammation. We aimed to investigate U. parvum serovar 3 pathogenesis in vivo, using a sheep model, by investigating: MBA variation after long term (chronic) and short term (acute) durations of in utero ureaplasma infections, and the severity of chorioamnionitis and inflammation in other fetal tissues. Inocula of 2 × 10(7) colony-forming-units (CFU) of U. parvum serovar 3 (Up) or media controls (C) were injected intra-amniotically into pregnant ewes at one of three time points: day 55 (69d Up, n = 8; C69, n = 4); day 117 (7d Up, n = 8; C7, n = 2); and day 121 (3d Up, n = 8; C3, n = 2) of gestation (term = 145-150d). At day 124, preterm fetuses were delivered surgically. Samples of chorioamnion, fetal lung, and umbilical cord were: (i) snap frozen for subsequent ureaplasma culture, and (ii) fixed, embedded, sectioned and stained by haematoxylin and eosin stain for histological analysis. Selected fetal lung clinical ureaplasma isolates were cloned and filtered to obtain cultures from a single CFU. Passage 1 and clone 2 ureaplasma cultures were tested by western blot to demonstrate MBA variation. In acute durations of ureaplasma infection no MBA variants (3d Up) or very few MBA variants (7d Up) were present when compared to the original inoculum. However, numerous MBA size variants were generated in vivo (alike within contiguous tissues, amniotic fluid and fetal lung, but different variants were present within chorioamnion), during chronic, 69d exposure to ureaplasma infection. For the first time we have shown that the degree of ureaplasma MBA variation in vivo increased with the duration of gestation.

Ureaplasma parvum serovar 3 multiple banded antigen size variation after chronic intra-amniotic infection/colonization.

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James W Robinson

Full Text Available Ureaplasma species are the microorganisms most frequently associated with adverse pregnancy outcomes. The multiple banded antigen (MBA, a surface-exposed lipoprotein, is a key virulence factor of ureaplasmas. The MBA demonstrates size variation, which we have shown previously to be correlated with the severity of chorioamnion inflammation. We aimed to investigate U. parvum serovar 3 pathogenesis in vivo, using a sheep model, by investigating: MBA variation after long term (chronic and short term (acute durations of in utero ureaplasma infections, and the severity of chorioamnionitis and inflammation in other fetal tissues. Inocula of 2 × 10(7 colony-forming-units (CFU of U. parvum serovar 3 (Up or media controls (C were injected intra-amniotically into pregnant ewes at one of three time points: day 55 (69d Up, n = 8; C69, n = 4; day 117 (7d Up, n = 8; C7, n = 2; and day 121 (3d Up, n = 8; C3, n = 2 of gestation (term = 145-150d. At day 124, preterm fetuses were delivered surgically. Samples of chorioamnion, fetal lung, and umbilical cord were: (i snap frozen for subsequent ureaplasma culture, and (ii fixed, embedded, sectioned and stained by haematoxylin and eosin stain for histological analysis. Selected fetal lung clinical ureaplasma isolates were cloned and filtered to obtain cultures from a single CFU. Passage 1 and clone 2 ureaplasma cultures were tested by western blot to demonstrate MBA variation. In acute durations of ureaplasma infection no MBA variants (3d Up or very few MBA variants (7d Up were present when compared to the original inoculum. However, numerous MBA size variants were generated in vivo (alike within contiguous tissues, amniotic fluid and fetal lung, but different variants were present within chorioamnion, during chronic, 69d exposure to ureaplasma infection. For the first time we have shown that the degree of ureaplasma MBA variation in vivo increased with the duration of gestation.

Corynebacterium ulcerans cutaneous diphtheria.

Science.gov (United States)

Moore, Luke S P; Leslie, Asuka; Meltzer, Margie; Sandison, Ann; Efstratiou, Androulla; Sriskandan, Shiranee

2015-09-01

We describe the case of a patient with cutaneous diphtheria caused by toxigenic Corynebacterium ulcerans who developed a right hand flexor sheath infection and symptoms of sepsis such as fever, tachycardia, and elevated C-reactive protein, after contact with domestic cats and dogs, and a fox. We summarise the epidemiology, clinical presentation, microbiology, diagnosis, therapy, and public health aspects of this disease, with emphasis on improving recognition. In many European countries, C ulcerans has become the organism commonly associated with cutaneous diphtheria, usually seen as an imported tropical disease or resulting from contact with domestic and agricultural animals. Diagnosis relies on bacterial culture and confirmation of toxin production, with management requiring appropriate antimicrobial therapy and prompt administration of antitoxin, if necessary. Early diagnosis is essential for implementation of control measures and clear guidelines are needed to assist clinicians in managing clinical diphtheria. This case was a catalyst to the redrafting of the 2014 national UK interim guidelines for the public health management of diphtheria, released as final guidelines in March, 2015. Copyright © 2015 Elsevier Ltd. All rights reserved.

PCR-Múltiple para el diagnóstico de Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum y Ureaplasma urealyticum

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Nadia Rodríguez-Preval

2007-04-01

Full Text Available Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum y Ureaplasma urealyticum son especies relacionadas con enfermedades del tracto genitourinario, y particularmente con la uretritis no gonocócica (UNG en el hombre. Los cultivos de estos microorganismos resultan complicados, por lo que las técnicas moleculares, principalmente la reacción en cadena de la polimerasa (PCR, se han convertido en el principal método de detección de estos organismos. Objetivo: Implementar un método molecular basado en tecnología de genes para el diagnóstico de estas cuatro especies de micoplasmas genitales, aplicándolo en muestras clínicas de pacientes con UNG. Material y métodos: Se crearon las condiciones para un PCR-Múltiple para identificar estas especies empleando como muestra ADN de referencia, utilizando los juegos de cebadores complementarios a fragmentos de los genes de la proteína adhesiva de M. genitalium (MgPa, ARN ribosomal 16S de M. hominis, región espaciadora entre los genes del ARN ribosomal 16S y 23S de U. parvum, y de la región espaciadora adyacente al gen de la ureasa y específico para U. urealyticum, siendo un método específico y sensible. Resultados: Al analizar 34 muestras de exudado uretral, 27 correspondieron a la clase Mollicutes, obteniéndose 14,8% de positividad a M. genitalium, 18,5% a M. hominis, 11,1% a U. urealyticum y 3,7%. a U. parvum. Con este trabajo se realizó por primera vez el diagnóstico de M. genitalium, M. hominis, U. parvum y U. urealyticum en muestras uretrales de pacientes cubanos. Conclusión: Se recomienda incluir el diagnóstico de estas especies en un mayor número de pacientes cubanos con síntomas uretrales, para validar el método propuesto y conocer la relación de estos microorganismos con la UNG.

Characterization of an immunogenic glycocalyx on the surfaces of Cryptosporidium parvum oocysts and sporozoites.

Science.gov (United States)

Nanduri, J; Williams, S; Aji, T; Flanigan, T P

1999-04-01

Ruthenium red staining of Cryptosporidium parvum oocysts revealed the presence of a carbohydrate matrix on their outer bilayers that is characteristic of a glycocalyx. Surface labeling of intact oocysts identified material of high molecular weight (>10(6)) that reacted positively with sera from cryptosporidium-infected patients and with immunoglobulin A monoclonal antibodies.

INTESTINAL AND PULMONARY INFECTION BY Cryptosporidium parvum IN TWO PATIENTS WITH HIV/AIDS

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Fábio Tadeu Rodrigues REINA

2016-01-01

Full Text Available We describe two patients with HIV/AIDS who presented pulmonary and intestinal infection caused by Cryptosporidium parvum, with a fatal outcome. The lack of available description of changes in clinical signs and radiographic characteristics of this disease when it is located in the extra-intestinal region causes low prevalence of early diagnosis and a subsequent lack of treatment.

Assignment of sigma factors of RNA polymerase to promoters in Corynebacterium glutamicum

Czech Academy of Sciences Publication Activity Database

Dostálová, Hana; Holátko, Jiří; Busche, T.; Rucká, Lenka; Rapoport, Andrey; Halada, Petr; Nešvera, Jan; Kalinowski, J.; Pátek, Miroslav

2017-01-01

Roč. 7, JUN 23 (2017), s. 1-13, č. článku 133. ISSN 2191-0855 R&D Projects: GA ČR(CZ) GA17-06991S Institutional support: RVO:61388971 Keywords : Corynebacterium glutamicum * Promoter * Sigma factor Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.825, year: 2016

Systemic inflammatory response syndrome increases immobility-induced neuromuscular weakness.

Science.gov (United States)

Fink, Heidrun; Helming, Marc; Unterbuchner, Christoph; Lenz, Andrea; Neff, Frauke; Martyn, J A Jeevendra; Blobner, Manfred

2008-03-01

Inflammation and immobility are comorbid etiological factors inducing muscle weakness in critically ill patients. This study establishes a rat model to examine the effect of inflammation and immobilization alone and in combination on muscle contraction, histology, and acetylcholine receptor regulation. Prospective, randomized, experimental study. Animal laboratory of a university hospital. Sprague-Dawley rats. To produce systemic inflammation, rats (n = 34) received three consecutive intravenous injections of Corynebacterium parvum on days 0, 4, and 8. Control rats (n = 21) received saline. Both groups were further divided to have one hind limb either immobilized by pinning of knee and ankle joints or sham-immobilized (surgical leg). The contralateral nonsurgical leg of each animal served as control (nonsurgical leg). After 12 days, body weight and muscle mass were significantly reduced in all C. parvum animals compared with saline-injected rats. Immobilization led to local muscle atrophy. Normalized to muscle mass, tetanic contraction was reduced in the surgical leg after immobilization (7.64 +/- 1.91 N/g) and after inflammation (8.71 +/- 2.0 N/g; both p < .05 vs. sham immobilization and saline injection, 11.03 +/- 2.26 N/g). Histology showed an increase in inflammatory cells in all C. parvum-injected animals. Immobilization in combination with C. parvum injection had an additive effect on inflammation. Acetylcholine receptors were increased in immobilized muscles and in all muscles of C. parvum-injected animals. The muscle weakness in critically ill patients can be replicated in our novel rat model. Inflammation and immobilization independently lead to muscle weakness.

Point-of-Use Removal of Cryptosporidium parvum from Water: Independent Effects of Disinfection by Silver Nanoparticles and Silver Ions and by Physical Filtration in Ceramic Porous Media.

Science.gov (United States)

Abebe, Lydia S; Su, Yi-Hsuan; Guerrant, Richard L; Swami, Nathan S; Smith, James A

2015-11-03

Ceramic water filters (CWFs) impregnated with silver nanoparticles are a means of household-level water treatment. CWFs remove/deactivate microbial pathogens by employing two mechanisms: metallic disinfection and physical filtration. Herein we report on the independent effects of silver salt and nanoparticles on Cryptosporidium parvum and the removal of C. parvum by physical filtration in porous ceramic filter media. Using a murine (mouse) model, we observed that treatment of oocysts with silver nitrate and proteinate-capped silver nanoparticles resulted in decreased infection relative to untreated oocysts. Microscopy and excystation experiments were conducted to support the disinfection investigation. Heat and proteinate-capped silver-nanoparticle treatment of oocysts resulted in morphological modifications and decreased excystation rates of sporozoites. Subsequently, disk-shaped ceramic filters were produced to investigate the transport of C. parvum. Two factors were varied: sawdust size and clay-to-sawdust ratio. Five disks were prepared with combinations of 10, 16, and 20 mesh sawdust and sawdust percentage that ranged from 9 to 11%. C. parvum removal efficiencies ranged from 1.5 log (96.4%) to 2.1 log (99.2%). The 16-mesh/10% sawdust had the greatest mean reduction of 2.1-log (99.2%), though there was no statistically significant difference in removal efficiency. Based on our findings, physical filtration and silver nanoparticle disinfection likely contribute to treatment of C. parvum for silver impregnated ceramic water filters, although the contribution of physical filtration is likely greater than silver disinfection.

Structural Basis of a Thiol-Disulfide Oxidoreductase in the Hedgehog-Forming Actinobacterium Corynebacterium matruchotii.

Science.gov (United States)

Luong, Truc Thanh; Tirgar, Reyhaneh; Reardon-Robinson, Melissa E; Joachimiak, Andrzej; Osipiuk, Jerzy; Ton-That, Hung

2018-05-01

The actinobacterium Corynebacterium matruchotii has been implicated in nucleation of oral microbial consortia leading to biofilm formation. Due to the lack of genetic tools, little is known about basic cellular processes, including protein secretion and folding, in this organism. We report here a survey of the C. matruchotii genome, which encodes a large number of exported proteins containing paired cysteine residues, and identified an oxidoreductase that is highly homologous to the Corynebacterium diphtheriae thiol-disulfide oxidoreductase MdbA (MdbA Cd ). Crystallization studies uncovered that the 1.2-Å resolution structure of C. matruchotii MdbA (MdbA Cm ) possesses two conserved features found in actinobacterial MdbA enzymes, a thioredoxin-like fold and an extended α-helical domain. By reconstituting the disulfide bond-forming machine in vitro , we demonstrated that MdbA Cm catalyzes disulfide bond formation within the actinobacterial pilin FimA. A new gene deletion method supported that mdbA is essential in C. matruchotii Remarkably, heterologous expression of MdbA Cm in the C. diphtheriae Δ mdbA mutant rescued its known defects in cell growth and morphology, toxin production, and pilus assembly, and this thiol-disulfide oxidoreductase activity required the catalytic motif CXXC. Altogether, the results suggest that MdbA Cm is a major thiol-disulfide oxidoreductase, which likely mediates posttranslocational protein folding in C. matruchotii by a mechanism that is conserved in Actinobacteria IMPORTANCE The actinobacterium Corynebacterium matruchotii has been implicated in the development of oral biofilms or dental plaque; however, little is known about the basic cellular processes in this organism. We report here a high-resolution structure of a C. matruchotii oxidoreductase that is highly homologous to the Corynebacterium diphtheriae thiol-disulfide oxidoreductase MdbA. By biochemical analysis, we demonstrated that C. matruchotii MdbA catalyzes disulfide

Function of Corynebacterium glutamicum promoters in Eschrichia coli, Streptomyces lividans, and Baccillus subtilis

Czech Academy of Sciences Publication Activity Database

Pátek, Miroslav; Muth, G.; Wohlleben, W.

2003-01-01

Roč. 104, - (2003), s. 325-334 ISSN 0168-1656 R&D Projects: GA AV ČR IPP1050128; GA ČR GA525/01/0916 Institutional research plan: CEZ:AV0Z5020903 Keywords : corynebacterium glutamicum * escherichia coli * promoters Subject RIV: EE - Microbiology, Virology Impact factor: 2.543, year: 2003

Ureaplasma parvum genotype, combined vaginal colonisation with Candida albicans, and spontaneous preterm birth in an Australian cohort of pregnant women.

Science.gov (United States)

Payne, Matthew S; Ireland, Demelza J; Watts, Rory; Nathan, Elizabeth A; Furfaro, Lucy L; Kemp, Matthew W; Keelan, Jeffrey A; Newnham, John P

2016-10-18

Detection of Ureaplasma, Mycoplasma and Candida spp. in the vagina during pregnancy has previously been associated with preterm birth (PTB). However, the prevalence of these microorganisms and the associated obstetric risks (likely to be population-specific) have not been determined in Australian women; furthermore, in the case of Ureaplasma spp., very few studies have attempted characterisation at the species level and none have examined genotype/serovar status to further refine risk assessment. In order to address these issues we sampled the vaginal fluid of 191 pregnant Australian women at three time points in pregnancy. Culture methods were used for detection of Ureaplasma spp. and Candida spp., and real-time PCR was used for speciation of U. parvum and U. urealyticum, non-albicans Candida spp., Mycoplasma hominis and Mycoplasma genitalium. High-resolution melt PCR was used to genotype U. parvum. Data on various lifestyle factors (including sex during pregnancy and smoking), antimicrobial use and pregnancy outcome were collected on all participants. Chi-square tests were used to assess the association of vaginal microorganisms with PTB. Detection of Ureaplasma spp. was higher among spontaneous PTB cases, specifically in the presence of U. parvum [77 % preterm (95 % confidence interval (CI) 50-100 %) vs. 36 % term (CI: 29-43 %), p = 0.004], but not U. urealyticum. The association with PTB strengthened when U. parvum genotype SV6 was detected (54 % preterm (CI: 22-85 %) vs. 15 % term (CI: 10-20 %), p = 0.002); this genotype was also present in 80 % (4/5) of cases of PTB Ureaplasma spp. in the vagina confers an increased risk of spontaneous PTB, findings which may be useful in risk assessment for identifying women who would benefit from antimicrobial treatment.

Inactivation of oocysts of Cryptosporidium parvum by ultraviolet irradiation

International Nuclear Information System (INIS)

Campbell, A.T.; Robertson, L.J.; Snowball, M.R.; Smith, H.V.

1995-01-01

Inactivation of oocysts of Cryptosporidium parvum in clean water using a novel design of an ultraviolet disinfection system was assessed by a vital dye assay and by in vitro excystation. The disinfection unit system is designed to expose the oocysts to ultraviolet radiation on two filters, providing a maximum total exposure to ultraviolet radiation of 8748 mW s cm −2 . Results revealed a reduction in oocyst viability of over two logs, indicating that this treatment has exciting potential as an additional treatment for water already treated by conventional methods. However, these data are only preliminary results using one isolate of oocysts and further trials must be conducted before this system could be recommended for use

Characterization of Staphylococcus and Corynebacterium clusters in the human axillary region.

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Chris Callewaert

Full Text Available The skin microbial community is regarded as essential for human health and well-being, but likewise plays an important role in the formation of body odor in, for instance, the axillae. Few molecular-based research was done on the axillary microbiome. This study typified the axillary microbiome of a group of 53 healthy subjects. A profound view was obtained of the interpersonal, intrapersonal and temporal diversity of the human axillary microbiota. Denaturing gradient gel electrophoresis (DGGE and next generation sequencing on 16S rRNA gene region were combined and used as extent to each other. Two important clusters were characterized, where Staphylococcus and Corynebacterium species were the abundant species. Females predominantly clustered within the Staphylococcus cluster (87%, n = 17, whereas males clustered more in the Corynebacterium cluster (39%, n = 36. The axillary microbiota was unique to each individual. Left-right asymmetry occurred in about half of the human population. For the first time, an elaborate study was performed on the dynamics of the axillary microbiome. A relatively stable axillary microbiome was noticed, although a few subjects evolved towards another stable community. The deodorant usage had a proportional linear influence on the species diversity of the axillary microbiome.

The role of free-ranging, captive, and domestic birds of Western Poland in environmental contamination with Cryptosporidium parvum oocysts and Giardia lamblia cysts.

Science.gov (United States)

Majewska, Anna C; Graczyk, Thaddeus K; Słodkowicz-Kowalska, Anna; Tamang, Leena; Jedrzejewski, Szymon; Zduniak, Piotr; Solarczyk, Piotr; Nowosad, Andrzej; Nowosad, Piotr

2009-04-01

As Cryptosporidium parvum and Giardia lamblia can be disseminated in the environment by avian hosts, a total of 499 fecal dropping from 308 free-ranging, 90 captive, and 101 domestic birds were tested by conventional, immunological, and molecular techniques for these human enteropathogens. Twenty-six (5.2%) tested positive for G. lamblia cysts and 19 (3.8%) for C. parvum oocysts. A bird total of 23 (7.5%) free-ranging, two (2.2%) captive, and one (0.1%) domestic tested positive for cysts, whereas 18 (5.8%) free-ranging, one (1.1%) captive, and zero livestock birds tested positive for oocysts. G. lamblia cysts and C. parvum oocysts were found significantly more frequently in fecal droppings of free-ranging aquatic birds than in birds not normally associated with water. No specimen tested positive for both pathogens simultaneously. Aquatic birds represent an important epidemiologic link in water-associated transmission cycles of Cryptosporidium and Giardia and play a significant role in environmental contamination of aquatic habitats with these anthropozoonotic pathogens.

Removal of Cryptosporidium parvum oocysts in low quality water using Moringa oleifera seed extract as coagulant

DEFF Research Database (Denmark)

Petersen, Heidi Huus; Petersen, T. B.; Enemark, Heidi

2016-01-01

was carried out to investigate the effect of a coagulant produced from seeds of the Moringa oleifera tree (MO) in reducing Cryptosporidium parvum oocysts and turbidity in wastewater and stream water. Glass jars (n = 60) containing 500 mL wastewater obtained from the inlet to the primary settling tanks from...

Discovery of ebselen as an inhibitor of Cryptosporidium parvum glucose-6-phosphate isomerase (CpGPI) by high-throughput screening of existing drugs.

Science.gov (United States)

Eltahan, Rana; Guo, Fengguang; Zhang, Haili; Xiang, Lixin; Zhu, Guan

2018-04-01

Cryptosporidium parvum is a water-borne and food-borne apicomplexan pathogen. It is one of the top four diarrheal-causing pathogens in children under the age of five in developing countries, and an opportunistic pathogen in immunocompromised individuals. Unlike other apicomplexans, C. parvum lacks Kreb's cycle and cytochrome-based respiration, thus relying mainly on glycolysis to produce ATP. In this study, we characterized the primary biochemical features of the C. parvum glucose-6-phosphate isomerase (CpGPI) and determined its Michaelis constant towards fructose-6-phosphate (K m  = 0.309 mM, V max  = 31.72 nmol/μg/min). We also discovered that ebselen, an organoselenium drug, was a selective inhibitor of CpGPI by high-throughput screening of 1200 known drugs. Ebselen acted on CpGPI as an allosteric noncompetitive inhibitor (IC 50  = 8.33 μM; K i  = 36.33 μM), while complete inhibition of CpGPI activity was not achieved. Ebselen could also inhibit the growth of C. parvum in vitro (EC 50  = 165 μM) at concentrations nontoxic to host cells, albeit with a relatively small in vitro safety window of 4.2 (cytotoxicity TC 50 on HCT-8 cells = 700 μM). Additionally, ebselen might also target other enzymes in the parasite, leading to the parasite growth reduction. Therefore, although ebselen is useful in studying the inhibition of CpGPI enzyme activity, further proof is needed to chemically and/or genetically validate CpGPI as a drug target. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Viability Assessment of Cryptosporidium parvum Oocysts by Vital Dyes: Dry Mounts Overestimate the Number of “Ghost” Oocysts

DEFF Research Database (Denmark)

Petersen, Heidi Huus; Enemark, Heidi L.

2017-01-01

Viability assessment of Cryptosporidium parvum oocysts is crucial for evaluation of the public health significance of this important zoonotic protozoon. Viability is commonly assessed in wet mounts after acid pretreatmentand staining with fluorogenic vital dyes. However, in some studies, oocyst v...

Comparison of Assays for Sensitive and Reproducible Detection of Cell Culture-Infectious Cryptosporidium parvum and Cryptosporidium hominis in Drinking Water

Science.gov (United States)

Di Giovanni, George D.; Rochelle, Paul A.

2012-01-01

This study compared the three most commonly used assays for detecting Cryptosporidium sp. infections in cell culture: immunofluorescent antibody and microscopy assay (IFA), PCR targeting Cryptosporidium sp.-specific DNA, and reverse transcriptase PCR (RT-PCR) targeting Cryptosporidium sp.-specific mRNA. Monolayers of HCT-8 cells, grown in 8-well chamber slides or 96-well plates, were inoculated with a variety of viable and inactivated oocysts to assess assay performance. All assays detected infection with low doses of flow cytometry-enumerated Cryptosporidium parvum oocysts, including infection with one oocyst and three oocysts. All methods also detected infection with Cryptosporidium hominis. The RT-PCR assay, IFA, and PCR assay detected infection in 23%, 25%, and 51% of monolayers inoculated with three C. parvum oocysts and 10%, 9%, and 16% of monolayers inoculated with one oocyst, respectively. The PCR assay was the most sensitive, but it had the highest frequency of false positives with mock-infected cells and inactivated oocysts. IFA was the only infection detection assay that did not produce false positives with mock-infected monolayers. IFA was also the only assay that detected infections in all experiments with spiked oocysts recovered from Envirochek capsules following filtration of 1,000 liters of treated water. Consequently, cell culture with IFA detection is the most appropriate method for routine and sensitive detection of infectious Cryptosporidium parvum and Cryptosporidium hominis in drinking water. PMID:22038611

Plasmid Vectors for Testing In Vivo Promoter Activities in Corynebacterium glutamicum and Rhodococcus erythropolis

Czech Academy of Sciences Publication Activity Database

Knoppová, Monika; Phensaijai, M.; Veselý, Martin; Zemanová, Martina; Nešvera, Jan; Pátek, Miroslav

2007-01-01

Roč. 55, - (2007), s. 234-239 ISSN 0343-8651 R&D Projects: GA ČR GA526/04/0542; GA ČR GA204/06/0330 Institutional research plan: CEZ:AV0Z50200510 Keywords : corynebacterium * rhodoccoccus * promoter-probe vectors Subject RIV: EE - Microbiology , Virology Impact factor: 1.167, year: 2007

Comparison of the Triage Micro Parasite Panel and Microscopy for the Detection of Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Cryptosporidium parvum in Stool Samples Collected in Kenya

Directory of Open Access Journals (Sweden)

Brett Swierczewski

2012-01-01

Full Text Available Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum are three of the most important parasitic causes of acute diarrhea worldwide. Laboratory diagnosis of these parasites is usually done by ova and parasite examination (O&P examination via microscopy. The sensitivity and specificity of O&P examination varies among laboratories and can be labor intensive and time consuming. The Triage Micro Parasite Panel (BioSite, San Diego, California is an enzyme immunoassay kit that can detect E. histolytica/E. dispar, G. lamblia, and C. parvum simultaneously using fresh or frozen stool. The present study evaluated the Triage Micro Parasite Panel in detecting E. histolytica/E. dispar, G. lamblia, and C. parvum compared to O&P examination in 266 stool samples collected at medical facilities in Kenya. The sensitivity and specificity results for the Triage Micro Parasite Panel were: for E. histolytica/E. dispar: 100%, 100%, G. lamblia: 100%, 100% and C. parvum: 73%, 100%. There was no evidence of cross reactivity using the kit with other parasites identified in the stool specimens. These results indicate that the Triage Micro Parasite Panel is a highly sensitive kit that can be used for screening purposes in large scale studies or outbreak investigations or as a possible alternative to O&P examination.

Carrier state of Haemophilus influenzae type b (Hib, Streptococcus pneumoniae, Streptococcus pyogenes, Neisseria meningitidis and Corynebacterium diphtheriae among school children in Pokhara, Nepal

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Dharm Raj Bhatta

2014-02-01

Full Text Available Objective: To determine the incidence of carrier state of Haemophilus influenzae type b, Streptococcus pneumoniae (S. pneumoniae, Streptococcus pyogenes, Neisseria meningitidis and Corynebacterium diphtheriae among school children. Methods: Specimen from posterior pharyngeal wall and tonsils were collected on calcium alginate coated swabs from 1 02 participants. Processing of specimen and antimicrobial susceptibility testing was done by standard procedures. Results: Potential pathogens isolated in our study were S. pneumoniae (14.7%, Staphylococcus aureus (12.7%, Corynebacterium diphtheriae (3.9%, Streptococcus pyogenes (3.9% and Haemophilus influenzae (1.9%. Important findings in antibiogram include high resistance of S. pneumoniae to penicillin (73% and resistance of Staphylococcus aureus to oxacillin (23%. Conclusions: Pharyngeal colonization by S. pneumoniae among school children was found high and there is need of introduction of pneumococcal vaccines among children. Despite expected universal vaccination, pharyngeal colonization by Corynebacterium diphtheriae is possible and there is possibility of transmission.

Corynebacterium jeikeium jk0268 constitutes for the 40 amino acid long PorACj, which forms a homooligomeric and anion-selective cell wall channel.

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Narges Abdali

Full Text Available Corynebacterium jeikeium, a resident of human skin, is often associated with multidrug resistant nosocomial infections in immunodepressed patients. C. jeikeium K411 belongs to mycolic acid-containing actinomycetes, the mycolata and contains a channel-forming protein as judged from reconstitution experiments with artificial lipid bilayer experiments. The channel-forming protein was present in detergent treated cell walls and in extracts of whole cells using organic solvents. A gene coding for a 40 amino acid long polypeptide possibly responsible for the pore-forming activity was identified in the known genome of C. jeikeium by its similar chromosomal localization to known porH and porA genes of other Corynebacterium strains. The gene jk0268 was expressed in a porin deficient Corynebacterium glutamicum strain. For purification temporarily histidine-tailed or with a GST-tag at the N-terminus, the homogeneous protein caused channel-forming activity with an average conductance of 1.25 nS in 1M KCl identical to the channels formed by the detergent extracts. Zero-current membrane potential measurements of the voltage dependent channel implied selectivity for anions. This preference is according to single-channel analysis caused by some excess of cationic charges located in the channel lumen formed by oligomeric alpha-helical wheels. The channel has a suggested diameter of 1.4 nm as judged from the permeability of different sized hydrated anions using the Renkin correction factor. Surprisingly, the genome of C. jeikeium contained only one gene coding for a cell wall channel of the PorA/PorH type found in other Corynebacterium species. The possible evolutionary relationship between the heterooligomeric channels formed by certain Corynebacterium strains and the homooligomeric pore of C. jeikeium is discussed.

Metabolic engineering of the L-valine biosynthesis pathway in Corynebacterium glutamicum using promoter activity modulation

Czech Academy of Sciences Publication Activity Database

Holátko, Jiří; Elišáková, Veronika; Prouza, Marek; Sobotka, Miroslav; Nešvera, Jan; Pátek, Miroslav

2009-01-01

Roč. 139, č. 3 (2009), s. 203-210 ISSN 0168-1656 R&D Projects: GA ČR GA204/06/0330 Institutional research plan: CEZ:AV0Z50200510 Keywords : corynebacterium glutamicum * valine production * promoters Subject RIV: EE - Microbiology, Virology Impact factor: 2.881, year: 2009

Corynebacterium renale as a cause of reactions to the complement fixation test for Johne's disease

NARCIS (Netherlands)

Gilmour, N.J.L.; Goudswaard, J.

Complement fixation (C.F.) tests and fluorescent antibody (F.A.) tests were carried out on sera from rabbits inoculated with Corynebacterium renale and Mycobacterium johnei, and on sera from cattle with C. renale pyelonephritis and with Johne's disease. Cross-reactions were a feature of the C.F.

Flux through the tetrahydrodipicolinate succinylase pathway is dispensable for L-lysine production in Corynebacterium glutamicum.

Science.gov (United States)

Shaw-Reid, C A; McCormick, M M; Sinskey, A J; Stephanopoulos, G

1999-03-01

The N-succinyl-LL-diaminopimelate desuccinylase gene (dapE) in the four-step succinylase branch of the L-lysine biosynthetic pathway of Corynebacterium glutamicum was disrupted via marker-exchange mutagenesis to create a mutant strain that uses only the one-step meso-diaminopimelate dehydrogenase branch to overproduce lysine. This mutant strain grew and utilized glucose from minimal medium at the same rate as the parental strain. In addition, the dapE- strain produced lysine at the same rate as its parent strain. Transformation of the parental and dapE- strains with the amplified meso-diaminopimelate dehydrogenase gene (ddh) on a plasmid did not affect lysine production in either strain, despite an eightfold amplification of the activity of the enzyme. These results indicate that the four-step succinylase pathway is dispensable for lysine overproduction in shake-flask culture. In addition, the one-step meso-diaminopimelate dehydrogenase pathway does not limit lysine flux in Corynebacterium under these conditions.

A quantitative analysis of Ureaplasma urealyticum and Ureaplasma parvum compared with host immune response in preterm neonates at risk of developing bronchopulmonary dysplasia.

Science.gov (United States)

Payne, Matthew S; Goss, Kevin C W; Connett, Gary J; Legg, Julian P; Bruce, Ken D; Chalker, Vicki

2012-03-01

Multiplex, real-time PCR for the identification of Ureaplasma urealyticum and Ureaplasma parvum was performed on nucleic acids extracted from sequential endotracheal aspirates obtained from preterm neonates born at Ureaplasma spp. were identified in 5 of 13 neonates studied. In most cases, the DNA load of the detected Ureaplasma species was low and decreased over time. In addition, changes in detectable Ureaplasma species DNA did not relate to changes in the inflammatory marker C-reactive protein (CRP) or respiratory status. All but two blood samples obtained at times of suspected sepsis were culture positive for other microorganisms; the species cultured were typically coagulase-negative staphylococci and were associated with increased levels of CRP (>10 mg/liter). This study was limited by the small number of patients examined and does not have the power to support or contradict the hypothesis that postnatal lung infection with Ureaplasma parvum is causally related to bronchopulmonary dysplasia (BPD) or adverse respiratory outcomes after preterm birth. However, in this study, increases in CRP levels were not associated with patients in whom Ureaplasma parvum was detected, in contrast to the detection of other bacterial species.

Wastewater treatment with Moringa oleifera seed extract: Impact on turbidity and sedimentation of Cryptosporidium parvum oocysts

DEFF Research Database (Denmark)

Petersen, Heidi H.; Woolsey, Ian; Dalsgaard, Anders

produced from seeds of the Moringa oleifera tree (MO) in reducing Cryptosporidium parvum oocysts and turbidity in wastewater. To a total of 5 x 12 glass jars containing 500 ml wastewater samples from a Danish treatment plant, 1.2 x 106 ± 1.2 x 105 oocysts L-1 were added. To half of the wastewater samples 8...

Improved L-ornithine production in Corynebacterium crenatum by introducing an artificial linear transacetylation pathway.

Science.gov (United States)

Shu, Qunfeng; Xu, Meijuan; Li, Jing; Yang, Taowei; Zhang, Xian; Xu, Zhenghong; Rao, Zhiming

2018-05-04

L-Ornithine is a non-protein amino acid with extensive applications in the food and pharmaceutical industries. In this study, we performed metabolic pathway engineering of an L-arginine hyper-producing strain of Corynebacterium crenatum for L-ornithine production. First, we amplified the L-ornithine biosynthetic pathway flux by blocking the competing branch of the pathway. To enhance L-ornithine synthesis, we performed site-directed mutagenesis of the ornithine-binding sites to solve the problem of L-ornithine feedback inhibition for ornithine acetyltransferase. Alternatively, the genes argA from Escherichia coli and argE from Serratia marcescens, encoding the enzymes N-acetyl glutamate synthase and N-acetyl-L-ornithine deacetylase, respectively, were introduced into Corynebacterium crenatum to mimic the linear pathway of L-ornithine biosynthesis. Fermentation of the resulting strain in a 5-L bioreactor allowed a dramatically increased production of L-ornithine, 40.4 g/L, with an overall productivity of 0.673 g/L/h over 60 h. This demonstrates that an increased level of transacetylation is beneficial for L-ornithine biosynthesis.

Effect of Cryptosporidium parvum infection on the absorptive capacity and paracellular permeability of the small intestine in neonatal calves

Czech Academy of Sciences Publication Activity Database

Klein, P.; Kleinová, T.; Volek, Z.; Šimůnek, Jiří

2008-01-01

Roč. 152, 1-2 (2008), s. 53-59 ISSN 0304-4017 Institutional research plan: CEZ:AV0Z50450515 Keywords : calves * cryptosporidium parvum * intestinal absorption Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.039, year: 2008

Second outbreak of infection with a rare Cryptosporidium parvum genotype in schoolchildren associated with contact with lambs/goat kids at a holiday farm in Norway.

Science.gov (United States)

Lange, H; Johansen, O H; Vold, L; Robertson, L J; Anthonisen, I L; Nygard, K

2014-10-01

In March 2012, a second outbreak of Cryptosporidium parvum affected children following a stay at a holiday farm in Norway; the first outbreak occurred in 2009. We studied a cohort of 145 schoolchildren who had visited the farm, of which 40 (28%) were cases. Cryptosporidium oocysts were detected in faecal samples from humans, goat kids and lambs. Molecular studies revealed C. parvum subtype IIa A19G1R1 in all samples including human samples from the 2009 outbreak. A dose-response relationship was found between the number of optional sessions with animals and illness, increasing from two sessions [risk ratio (RR) 2·7, 95% confidence interval (CI) 0·6-11·5] to six sessions (RR 8·0, 95% CI 1·7-37·7). The occurrence of two outbreaks 3 years apart, with the same subtype of C. parvum, suggests that the parasite is established in the farm's environment. We recommend greater emphasis on hand hygiene and routines related to animal contact.

Ureaplasma parvum and Mycoplasma genitalium are found to be significantly associated with microscopy-confirmed urethritis in a routine genitourinary medicine setting.

Science.gov (United States)

Cox, Ciara; McKenna, James P; Watt, Alison P; Coyle, Peter V

2016-09-01

Inflammation of the urethra defined by an excess of polymorphonuclear leukocytes in the absence of sexually transmitted Chlamydia trachomatis and Neisseria gonorrhoeae is called non-chlamydial non-gonococcal urethritis (NCNGU). Although Mycoplasma genitalium is now recognised as causing a sexually transmitted infection, the clinical significance of the other Mollicute species is less clear. This study used specific real-time quantitative polymerase chain reaction assays to detect and quantify four Mollicute species, M. genitalium, M. hominis, Ureaplasma urealyticum and U. parvum, in urine specimens from men with and without NCNGU. A total of 165 urine specimens from male patients attending a genitourinary medicine clinic were eligible for the study, with microscopy-confirmed (≥5 polymorphonuclear leukocytes in urethral swab) NCNGU in 75 (45.5%) and non-confirmed NCNGU in 90 (54.5%). Chi-squared statistical analysis indicated a significantly higher prevalence of U. parvum (17.3% vs. 5.6%; p = 0.03) and M. genitalium (12% vs. 0%; p < 0.001) in NCNGU. In a subset analysis, M. genitalium was also significantly (p = 0.03) higher in men who have sex with men (MSM; 13.5%) compared to non-MSM (3.1%). No significant associations were reported for U. urealyticum and M. hominis In conclusion, this study supports a clinically significant role in NGNCU for both U. parvum and M. genitalium. © The Author(s) 2015.

Multiplex polymerase chain reaction to identify and determine the toxigenicity of Corynebacterium spp with zoonotic potential and an overview of human and animal infections

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Luciene de Fátima Costa Torres

2013-05-01

Full Text Available Corynebacterium diphtheriae, Corynebacterium ulcerans and Corynebacterium pseudotuberculosis constitute a group of potentially toxigenic microorganisms that are related to different infectious processes in animal and human hosts. Currently, there is a lack of information on the prevalence of disease caused by these pathogens, which is partially due to a reduction in the frequency of routine laboratory testing. In this study, a multiplex polymerase chain reaction (mPCR assay that can simultaneously identify and determine the toxigenicity of these corynebacterial species with zoonotic potential was developed. This assay uses five primer pairs targeting the following genes: rpoB (Corynebacterium spp, 16S rRNA (C. ulcerans and C. pseudotuberculosis, pld (C. pseudotuberculosis, dtxR (C. diphtheriae and tox [diphtheria toxin (DT ]. In addition to describing this assay, we review the literature regarding the diseases caused by these pathogens. Of the 213 coryneform strains tested, the mPCR results for all toxigenic and non-toxigenic strains of C . diphtheriae, C. ulcerans and C. pseudotuberculosis were in 100% agreement with the results of standard biochemical tests and PCR-DT. As an alternative to conventional methods, due to its advantages of specificity and speed, the mPCR assay used in this study may successfully be applied for the diagnosis of human and/or animal diseases caused by potentially toxigenic corynebacterial species.

Clinical role of Ureaplasma parvum and Ureaplasma urealyticum presence in female lower urogenital tract: Is there a place for routine screening and treatment?

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Maruška Marovt

2014-10-01

Full Text Available Sexually transmitted infections represent major health problem in females all over the world if remained undiagnosed and untreated. They can have adverse influence on reproduction and health of a mother and a newborn. The development of molecular methods has permitted the detection of an array of microbes whose pathologic roles in urogenital infections need to be further studied. Ureaplasmas (Ureaplasma spp., being originally found in 1954 from male urogenital tract, are prokaryotic cells without a cell wall, ranging from 0.1 to 1 μm in length. Fourteen known Ureaplasma serovars have been divided in two species based on their phenotypic and genotypic features, Ureaplasma parvum and Ureaplasma urealyticum detected and identified separately using polymerase chain reaction assays. Both are generally considered as genital tract commensals. U. urealyticum is most probably associated with male urethritis which has not been found for U. parvum. Recent studies with supposedly healthy women reported their detection rate between 18-87 % for U. parvum and 6-10 % for U. urealyticum. Even though they have been found to be associated with chorioamnionitis, preterm birth and perinatal complications more commonly then other commensals in this region the rising question regarding their pathogenic role in females remains unsolved and the guidelines regarding the diagnostic screening and treatment are inconsistent. The aim of our paper is to review the microbiological characteristics, diagnostic methods and epidemiology of newly differentiated U. parvum and U. urealyticum, and to assess evidence speaking pro and contra their clinical role in causing lower urogenital tract infection in women. Since both bacteria are susceptible to antimicrobials it is of utmost importance for clinicians to decide whether or not to search for one or both of them routinely and treat accordingly in order to prevent ascending upper genital tract infection as well as complications in

Investigating Attachment Behaviors of Cryptosporidium Parvum Oocysts Using Collision Efficiency in Laboratory Column Experiments

Science.gov (United States)

Park, Y.; Hou, L.; Atwill, R.; Packman, A. I.; Harter, T.

2009-12-01

Cryptosporidium is one of the most common enteric parasites of humans and domestic animals, and a number of outbreaks of Cryprosporidiosis, a diarrheal disease caused by Cryptosporidium have been reported worldwide. Natural porous media has been demonstrated to be an effective filter for removing Cryptosporidium parvum from contaminated water and the amount of Cryptosporidium filtered is known to be highly dependent on physical and chemical conditions of the porous media and the water. Cryptosporidium deposition in saturated porous media involves two main steps: approach and attachment. In contrast to the approach mechanisms, attachment processes have not been systematically described to predict a priori because theories that represent attachment behavior (colloid stability) such as DLVO are insufficient to explain experimental data. For this reason, attachment efficiency is calculated based on empirical data, typically experimental breakthrough curves in laboratory columns or field experiments. In this study, collision (attachment) efficiencies (α) of C. parvum oocyst were calculated to test the effect of chemical property changes on the association of oocysts with sand grains. The breakthrough curve data obtained from twelve column experiments and three models were employed to calculate single collector efficiency (η) and α. The first ten experiments were conducted by changing ionic strength and pH, and mixing with natural sediments under the same physical properties (same η). Our experiment results show that iron coating or clay/suspended solids mixture drastically enhanced oocyst deposition. The experiments also showed that increase in ionic strength and decrease in pH enhanced the attachment efficiency. However, the experiment with 100mM NaCl resulted in low attachment efficiency and the experiment with pH 8.5 showed similar attachment efficiency to the one at pH 7. Based on the results from two additional experiments with different flow velocities, it

A Novel Corynebacterium glutamicum l-Glutamate Exporter.

Science.gov (United States)

Wang, Yu; Cao, Guoqiang; Xu, Deyu; Fan, Liwen; Wu, Xinyang; Ni, Xiaomeng; Zhao, Shuxin; Zheng, Ping; Sun, Jibin; Ma, Yanhe

2018-03-15

Besides metabolic pathways and regulatory networks, transport systems are also pivotal for cellular metabolism and hyperproduction of biochemicals using microbial cell factories. The identification and characterization of transporters are therefore of great significance for the understanding and engineering of transport reactions. Herein, a novel l-glutamate exporter, MscCG2, which exists extensively in Corynebacterium glutamicum strains but is distinct from the only known l-glutamate exporter, MscCG, was discovered in an industrial l-glutamate-producing C. glutamicum strain. MscCG2 was predicted to possess three transmembrane helices in the N-terminal region and located in the cytoplasmic membrane, which are typical structural characteristics of the mechanosensitive channel of small conductance. MscCG2 has a low amino acid sequence identity (23%) to MscCG and evolved separately from MscCG with four transmembrane helices. Despite the considerable differences between MscCG2 and MscCG in sequence and structure, gene deletion and complementation confirmed that MscCG2 also functioned as an l-glutamate exporter and an osmotic safety valve in C. glutamicum Besides, transcriptional analysis showed that MscCG2 and MscCG genes were transcribed in similar patterns and not induced by l-glutamate-producing conditions. It was also demonstrated that MscCG2-mediated l-glutamate excretion was activated by biotin limitation or penicillin treatment and that constitutive l-glutamate excretion was triggered by a gain-of-function mutation of MscCG2 (A151V). Discovery of MscCG2 will enrich the understanding of bacterial amino acid transport and provide additional targets for exporter engineering. IMPORTANCE The exchange of matter, energy, and information with surroundings is fundamental for cellular metabolism. Therefore, studying transport systems that are essential for these processes is of great significance. Besides, transport systems of bacterial cells are usually related to

Optimization of lysine metabolism in Corynebacterium glutamicum

DEFF Research Database (Denmark)

Rytter, Jakob Vang

,000,000 tons. The aim of this project is to optimize the yield of lysine in C. glutamicum using metabolic engineering strategies. According to a genome scale model of C. glutamicum, theoretically there is much room for increasing the lysine yield (Kjeldsen and Nielsen 2009). Lysine synthesis requires NADPH......Commercial pig and poultry production use the essential amino acid lysine as a feed additive with the purpose of optimizing the feed utilization. Lysine is produced by a fermentation process involving either Corynebacterium glutamicum or Escherichia coli. The global annual production is around 1...... the project intends to eliminate. PGI catalyzes the conversion of alpha-D-glucose-6-phosphate to fructose-6-phosphate just downstream of the branch in the glycolysis, but it also catalyzes the reverse reaction. It is unknown whether up- or down-regulation of the pgi is required to increase the flux through...

Wastewater treatment with Moringa oleifera seed extract and impact on turbidity and sedimentation of Cryptosporidium parvum oocysts

DEFF Research Database (Denmark)

Petersen, Heidi Huus; Woolsey, Ian David; Dalsgaard, Anders

produced from seeds of the Moringa oleifera tree (MO) in reducing Cryptosporidium parvum oocysts and turbidity in wastewater. To a total of 5 x 12 glass jars containing 500 ml wastewater samples from a Danish treatment plant, 1.2 x 106 ± 1.2 x 105 oocysts L-1 were added. To half of the wastewater samples 8...

Molecular epidemiology of Corynebacterium pseudotuberculosis isolated from horses in California.

Science.gov (United States)

Haas, Dionei J; Dorneles, Elaine M S; Spier, Sharon J; Carroll, Scott P; Edman, Judy; Azevedo, Vasco A; Heinemann, Marcos B; Lage, Andrey P

2017-04-01

Corynebacterium pseudotuberculosis biovar Equi is an important pathogen of horses. It is increasing in frequency in the United States, and is responsible for various clinical forms of infection, including external abscesses, internal abscesses of the abdominal or thoracic cavities, and ulcerative lymphangitis. The host/pathogen factors dictating the form or severity of infection are currently unknown. Our recent investigations have shown that genotyping C. pseudotuberculosis isolates using enterobacterial repetitive intergenic consensus (ERIC)-PCR is useful for understanding the evolutionary genetics of the species as well for molecular epidemiology studies. The aims of the present study were to assess (i) the genetic diversity of C. pseudotuberculosis strains isolated from horses in California, United States and (ii) the epidemiologic relationships among isolates. One hundred and seven C. pseudotuberculosis biovar Equi isolates from ninety-five horses, and two C. pseudotuberculosis biovar Ovis strains, C. pseudotuberculosis ATCC 19410 T type strain and C. pseudotuberculosis 1002 vaccine strain, were fingerprinted using the ERIC 1+2-PCR. C. pseudotuberculosis isolated from horses showed a high genetic diversity, clustering in twenty-seven genotypes with a diversity index of 0.91. Minimal spanning tree showed four major clonal complexes with a pattern of temporal clustering. Strains isolated from the same horse showed identical ERIC 1+2-PCR genotype, with the exception of two strains isolated from the same animal that showed distinct genotypes, suggesting a co-infection. We found no strong genetic signals related to clinical form (including internal versus external infections). However, temporal clustering of genotypes was observed. Copyright © 2016. Published by Elsevier B.V.

Immobilazation of aerobic microorganisms on glassy sintered material, illustrated by the example of the production of L leucine using Corynebacterium glutamicum. Immobilisierung von aeroben Mikroorganismen an Glassintermaterial am Beispiel der L-Leucin-Produktion mit Corynebacterium glutamicum

Energy Technology Data Exchange (ETDEWEB)

Buechs, J.

1988-12-01

The aim of this study was to develop the carrier fixation of aerobic microorganisms on open-pore sintered glass material. The fermentative production of L-leucine from {alpha} cetonic isocaproic acid with Corynebacterium glutamicum was chosen as an example of a microbial process with a high demand of oxygen. (orig.).

Comparison between culture and a multiplex quantitative real-time polymerase chain reaction assay detecting Ureaplasma urealyticum and U. parvum.

Science.gov (United States)

Frølund, Maria; Björnelius, Eva; Lidbrink, Peter; Ahrens, Peter; Jensen, Jørgen Skov

2014-01-01

A novel multiplex quantitative real-time polymerase chain reaction (qPCR) for simultaneous detection of U. urealyticum and U. parvum was developed and compared with quantitative culture in Shepard's 10 C medium for ureaplasmas in urethral swabs from 129 men and 66 women, and cervical swabs from 61 women. Using culture as the gold standard, the sensitivity of the qPCR was 96% and 95% for female urethral and cervical swabs, respectively. In male urethral swabs the sensitivity was 89%. The corresponding specificities were 100%, 87% and 99%. The qPCR showed a linear increasing DNA copy number with increasing colour-changing units. Although slightly less sensitive than culture, this multiplex qPCR assay detecting U. urealyticum and U. parvum constitutes a simple and fast alternative to the traditional methods for identification of ureaplasmas and allows simultaneous species differentiation and quantitation in clinical samples. Furthermore, specimens overgrown by other bacteria using the culture method can be evaluated in the qPCR.

Comparison between culture and a multiplex quantitative real-time polymerase chain reaction assay detecting Ureaplasma urealyticum and U. parvum.

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Maria Frølund

Full Text Available A novel multiplex quantitative real-time polymerase chain reaction (qPCR for simultaneous detection of U. urealyticum and U. parvum was developed and compared with quantitative culture in Shepard's 10 C medium for ureaplasmas in urethral swabs from 129 men and 66 women, and cervical swabs from 61 women. Using culture as the gold standard, the sensitivity of the qPCR was 96% and 95% for female urethral and cervical swabs, respectively. In male urethral swabs the sensitivity was 89%. The corresponding specificities were 100%, 87% and 99%. The qPCR showed a linear increasing DNA copy number with increasing colour-changing units. Although slightly less sensitive than culture, this multiplex qPCR assay detecting U. urealyticum and U. parvum constitutes a simple and fast alternative to the traditional methods for identification of ureaplasmas and allows simultaneous species differentiation and quantitation in clinical samples. Furthermore, specimens overgrown by other bacteria using the culture method can be evaluated in the qPCR.

Synthetic promoter libraries for Corynebacterium glutamicum

DEFF Research Database (Denmark)

Rytter, Jakob Vang; Helmark, Søren; Chen, Jun

2014-01-01

The ability to modulate gene expression is an important genetic tool in systems biology and biotechnology. Here, we demonstrate that a previously published easy and fast PCR-based method for modulating gene expression in lactic acid bacteria is also applicable to Corynebacterium glutamicum. We co...... promoter library (SPL) technology is convenient for modulating gene expression in C. glutamicum and should have many future applications, within basic research as well as for optimizing industrial production organisms....... constructed constitutive promoter libraries based on various combinations of a previously reported C. glutamicum -10 consensus sequence (gngnTA(c/t)aaTgg) and the Escherichia coli -35 consensus, either with or without an AT-rich region upstream. A promoter library based on consensus sequences frequently found...... in low-GC Gram-positive microorganisms was also included. The strongest promoters were found in the library with a -35 region and a C. glutamicum -10 consensus, and this library also represents the largest activity span. Using the alternative -10 consensus TATAAT, which can be found in many other...

Cryptosporidium parvum infection in SCID mice infected with only one oocyst: qPCR assessment of parasite replication in tissues and development of digestive cancer.

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Sadia Benamrouz

Full Text Available Dexamethasone (Dex treated Severe Combined Immunodeficiency (SCID mice were previously described as developing digestive adenocarcinoma after massive infection with Cryptosporidium parvum as soon as 45 days post-infection (P.I.. We aimed to determine the minimum number of oocysts capable of inducing infection and thereby gastrointestinal tumors in this model. Mice were challenged with calibrated oocyst suspensions containing intended doses of: 1, 10, 100 or 10(5 oocysts of C. parvum Iowa strain. All administered doses were infective for animals but increasing the oocyst challenge lead to an increase in mice infectivity (P = 0.01. Oocyst shedding was detected at 7 days P.I. after inoculation with more than 10 oocysts, and after 15 days in mice challenged with one oocyst. In groups challenged with lower inocula, parasite growth phase was significantly higher (P = 0.005 compared to mice inoculated with higher doses. After 45 days P.I. all groups of mice had a mean of oocyst shedding superior to 10,000 oocyst/g of feces. The most impressive observation of this study was the demonstration that C. parvum-induced digestive adenocarcinoma could be caused by infection with low doses of Cryptosporidium, even with only one oocyst: in mice inoculated with low doses, neoplastic lesions were detected as early as 45 days P.I. both in the stomach and ileo-caecal region, and these lesions could evolve in an invasive adenocarcinoma. These findings show a great amplification effect of parasites in mouse tissues after challenge with low doses as confirmed by quantitative PCR. The ability of C. parvum to infect mice with one oocyst and to develop digestive adenocarcinoma suggests that other mammalian species including humans could be also susceptible to this process, especially when they are severely immunocompromised.

Cryptosporidium parvum infection in SCID mice infected with only one oocyst: qPCR assessment of parasite replication in tissues and development of digestive cancer.

Science.gov (United States)

Benamrouz, Sadia; Guyot, Karine; Gazzola, Sophie; Mouray, Anthony; Chassat, Thierry; Delaire, Baptiste; Chabé, Magali; Gosset, Pierre; Viscogliosi, Eric; Dei-Cas, Eduardo; Creusy, Colette; Conseil, Valerie; Certad, Gabriela

2012-01-01

Dexamethasone (Dex) treated Severe Combined Immunodeficiency (SCID) mice were previously described as developing digestive adenocarcinoma after massive infection with Cryptosporidium parvum as soon as 45 days post-infection (P.I.). We aimed to determine the minimum number of oocysts capable of inducing infection and thereby gastrointestinal tumors in this model. Mice were challenged with calibrated oocyst suspensions containing intended doses of: 1, 10, 100 or 10(5) oocysts of C. parvum Iowa strain. All administered doses were infective for animals but increasing the oocyst challenge lead to an increase in mice infectivity (P = 0.01). Oocyst shedding was detected at 7 days P.I. after inoculation with more than 10 oocysts, and after 15 days in mice challenged with one oocyst. In groups challenged with lower inocula, parasite growth phase was significantly higher (P = 0.005) compared to mice inoculated with higher doses. After 45 days P.I. all groups of mice had a mean of oocyst shedding superior to 10,000 oocyst/g of feces. The most impressive observation of this study was the demonstration that C. parvum-induced digestive adenocarcinoma could be caused by infection with low doses of Cryptosporidium, even with only one oocyst: in mice inoculated with low doses, neoplastic lesions were detected as early as 45 days P.I. both in the stomach and ileo-caecal region, and these lesions could evolve in an invasive adenocarcinoma. These findings show a great amplification effect of parasites in mouse tissues after challenge with low doses as confirmed by quantitative PCR. The ability of C. parvum to infect mice with one oocyst and to develop digestive adenocarcinoma suggests that other mammalian species including humans could be also susceptible to this process, especially when they are severely immunocompromised.

Canker and decline caused by Neofusiccocum parvum on Acacia melanoxylon in Italy

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Sidoti A

2016-12-01

Full Text Available In the spring of 2012, in reforested areas of Peloritani Mountains (Sicily, Italy a severe dieback of Acacia melanoxylon R. Brown was observed. The main symptoms on both young and adults plants consisted of elongated cankers on the trunks and epicormic shoots, wilt of the canopy and dieback interested mostly aged trees. The woody tissues showed browning beyond the cankers. Sapwood and heartwood appeared decayed with a brown to gray-greenish discoloration. One fungal species was consistently isolated from infected woody tissues, which was morphologically attributed to Neofusiccocum sp. The sequencing of the ITS regions of a representative isolate allowed to identify (99% similarity the species Neofusiccocum parvum (Pennycook & Samuels Crous, Slippers and Phillips, teleomorph Botryosphaeria parva Pennycook & Samuels. The pathogenicity tests have reproduced symptoms similar to those observed in the field. N. parvum is the aetiologic agent of mortality of australian blackwood observed in Sicily and to our knowledge this is the first report of this fungus on Acacia melanoxylon. It is a generalist pathogen, cosmopolitan, present in many temperate areas, Mediterranean and subtropical. The older Peloritani Mountains populations of australian blackwood seem particularly susceptible to the pathogen, the latter favored by the lack of silvicultural interventions that generate interspecific and intraspecific competition, as well as the increase and spread of the fungus. To minimize the consequential damage is necessary to adopt sanitation measures that would lower the fungal inoculum and program substitutions of this exotic species with others that have multiple functions suited to environments (e.g., Chestnut or encouraging the establishment and development of native species, such as the holm oak and shrub.

A novel role for autologous tumour cell vaccination in the immunotherapy of the poorly immunogenic B16-BL6 melanoma.

Science.gov (United States)

Geiger, J D; Wagner, P D; Shu, S; Chang, A E

1992-06-01

The growth of immunogenic tumours stimulates the generation of tumour-sensitized, but not functional, pre-effector T cells in the draining lymph nodes. These pre-effector cells can mature into effector cells upon in-vitro stimulation with anti-CD3 and IL-2. In the current study, using a defined, poorly immunogenic tumour, B16-BL6 melanoma, the pre-effector cell response was not evident during progressive tumour growth but was elicited by vaccination with irradiated tumour cells admixed with Corynebacterium parvum. After anti-CD3/IL-2 activation, these cells were capable of mediating the regression of established pulmonary metastases. The efficacy of the vaccine depended on the doses of both tumour cells and the adjuvant. While higher numbers of tumour cells were more effective, an optimal dose (12.5 micrograms) of C. parvum was required. The dose of irradiation was not a critical factor. After vaccination, kinetic studies revealed that the pre-effector cell response was evident 4 days later and declined after 14 days. These observations illustrate the potential role of active immunization in the cellular therapy of cancer.

Functional Expression of a DNA-Topoisomerase IB from Cryptosporidium parvum

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César Ordóñez

2009-01-01

Full Text Available Cryptosporidium parvum, one of the most important causative organisms of human diarrheas during childhood, contains a monomeric DNA-topoisomerase IB (CpTopIB in chromosome 7. Heterologous expression of CpTopIB gene in a budding yeast strain lacking this activity proves that the cryptosporidial enzyme is functional in vivo. The enzymatic activity is comprised in a single polypeptide, which contains all the structural features defining a fully active TopIB. Relaxation activity of the yeast extracts was detected only when CpTopIB ORF was expressed in a yeast expression system showing time and protein dependence under steady state kinetic conditions. The susceptibility of CpTopIB-transformed yeast to the irreversible inhibitor camptothecin and its water-soluble derivatives (topotecan and SN-38 was assessed.

Hydrologic and Vegetative Removal of Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii Surrogate Microspheres in Coastal Wetlands

Science.gov (United States)

Hogan, Jennifer N.; Daniels, Miles E.; Watson, Fred G.; Oates, Stori C.; Miller, Melissa A.; Conrad, Patricia A.; Shapiro, Karen; Hardin, Dane; Dominik, Clare; Melli, Ann; Jessup, David A.

2013-01-01

Constructed wetland systems are used to reduce pollutants and pathogens in wastewater effluent, but comparatively little is known about pathogen transport through natural wetland habitats. Fecal protozoans, including Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii, are waterborne pathogens of humans and animals, which are carried by surface waters from land-based sources into coastal waters. This study evaluated key factors of coastal wetlands for the reduction of protozoal parasites in surface waters using settling column and recirculating mesocosm tank experiments. Settling column experiments evaluated the effects of salinity, temperature, and water type (“pure” versus “environmental”) on the vertical settling velocities of C. parvum, G. lamblia, and T. gondii surrogates, with salinity and water type found to significantly affect settling of the parasites. The mesocosm tank experiments evaluated the effects of salinity, flow rate, and vegetation parameters on parasite and surrogate counts, with increased salinity and the presence of vegetation found to be significant factors for removal of parasites in a unidirectional transport wetland system. Overall, this study highlights the importance of water type, salinity, and vegetation parameters for pathogen transport within wetland systems, with implications for wetland management, restoration efforts, and coastal water quality. PMID:23315738

Detection and genotyping of Entamoeba histolytica, Entamoeba dispar, Giardia lamblia, and Cryptosporidium parvum by oligonucleotide microarray.

Science.gov (United States)

Wang, Zheng; Vora, Gary J; Stenger, David A

2004-07-01

Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum are the most frequently identified protozoan parasites causing waterborne disease outbreaks. The morbidity and mortality associated with these intestinal parasitic infections warrant the development of rapid and accurate detection and genotyping methods to aid public health efforts aimed at preventing and controlling outbreaks. In this study, we describe the development of an oligonucleotide microarray capable of detecting and discriminating between E. histolytica, Entamoeba dispar, G. lamblia assemblages A and B, and C. parvum types 1 and 2 in a single assay. Unique hybridization patterns for each selected protozoan were generated by amplifying six to eight diagnostic sequences/organism by multiplex PCR; fluorescent labeling of the amplicons via primer extension; and subsequent hybridization to a set of genus-, species-, and subtype-specific covalently immobilized oligonucleotide probes. The profile-based specificity of this methodology not only permitted for the unequivocal identification of the six targeted species and subtypes, but also demonstrated its potential in identifying related species such as Cryptosporidium meleagridis and Cryptosporidium muris. In addition, sensitivity assays demonstrated lower detection limits of five trophozoites of G. lamblia. Taken together, the specificity and sensitivity of the microarray-based approach suggest that this methodology may provide a promising tool to detect and genotype protozoa from clinical and environmental samples.

Identification of clinically relevant Corynebacterium strains by Api Coryne, MALDI-TOF-mass spectrometry and molecular approaches.

Science.gov (United States)

Alibi, S; Ferjani, A; Gaillot, O; Marzouk, M; Courcol, R; Boukadida, J

2015-09-01

We evaluated the Bruker Biotyper matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) for the identification of 97 Corynebacterium clinical in comparison to identification strains by Api Coryne and MALDI-TOF-MS using 16S rRNA gene and hypervariable region of rpoB genes sequencing as a reference method. C. striatum was the predominant species isolated followed by C. amycolatum. There was an agreement between Api Coryne strips and MALDI-TOF-MS identification in 88.65% of cases. MALDI-TOF-MS was unable to differentiate C. aurimucosum from C. minutissimum and C. minutissimum from C. singulare but reliably identify 92 of 97 (94.84%) strains. Two strains remained incompletely identified to the species level by MALDI-TOF-MS and molecular approaches. They belonged to Cellulomonas and Pseudoclavibacter genus. In conclusion, MALDI-TOF-MS is a rapid and reliable method for the identification of Corynebacterium species. However, some limits have been noted and have to be resolved by the application of molecular methods. Copyright © 2015. Published by Elsevier SAS.

Microbe Profile: Corynebacterium diphtheriae - an old foe always ready to seize opportunity.

Science.gov (United States)

Hoskisson, Paul A

2018-02-21

Corynebacterium diphtheriae is a globally important Gram-positive aerobic Actinobacterium capable of causing the toxin-mediated disease, diphtheria. Diphtheria was a major cause of childhood mortality prior to the introduction of the toxoid vaccine, yet it is capable of rapid resurgence following the breakdown of healthcare provision, vaccination or displacement of people. The mechanism and treatment of toxin-mediated disease is well understood, however there are key gaps in our knowledge on the basic biology of C. diphtheriae particularly relating to host colonisation, the nature of asymptomatic carriage, population genomics and host adaptation.

Complete Sucrose Metabolism Requires Fructose Phosphotransferase Activity in Corynebacterium glutamicum To Ensure Phosphorylation of Liberated Fructose

OpenAIRE

Dominguez, H.; Lindley, N. D.

1996-01-01

Sucrose uptake by Corynebacterium glutamicum involves a phosphoenolpyruvate-dependent sucrose phosphotransferase (PTS), but in the absence of fructokinase, further metabolism of the liberated fructose requires efflux of the fructose and reassimilation via the fructose PTS. Mutant strains lacking detectable fructose-transporting PTS activity accumulated fructose extracellularly but consumed sucrose at rates comparable to those of the wild-type strain.

Natural killer cells in leukemogenesis

Energy Technology Data Exchange (ETDEWEB)

Seidel, H.J.; Stolz, W.; Sutter, H.; Kreja, L.

1986-01-01

In order to relate a reduced natural killer (NK) cell function to leukemogenesis, NK cells in the spleen and peritoneal exudate cells, with and without stimulation by Corynebacterium parvum, were tested in mice of various strains after split dose irradiation and after leukemogenic treatment with butyl- and methylnitrosourea. The investigations included also mice submitted to non-leukemogenic irradiation (1 x 1.5 and 1 x 4.5 Gy) and mice submitted to an additional treatment with hydrocortisone, which delays leukemia development after methylnitrosourea. There was, indeed, a NK-cell depression, but no major differences were seen between mice prone to leukemia development and those after cytotoxic, but nonleukemogenic, treatment.

‘Corynebacterium fournierii,’ a new bacterial species isolated from the vaginal sample of a patient with bacterial vaginosis

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K. Diop

2017-07-01

Full Text Available Here we describe briefly ‘Corynebacterium fournierii’ strain Marseille P2948 (= CSUR P2948 = DSM103271, a new bacterium that was isolated from the vaginal sample of a 21-year-old woman with bacterial vaginosis.

Desulfurization of dibenzothiophene by Corynebacterium sp. strain SY1

International Nuclear Information System (INIS)

Omori, Toshio; Monna, L.; Saiki, Yuko; Kodama, Tohru

1992-01-01

Strain SY1, identified as a Corynebacterium sp., was isolated on the basis of the ability to utilize dibenzothiophene (DBT) as a sole source of sulfur. Strain SY1 could utilize a wide range of organic and inorganic sulfur compounds, such as DBT sulfone, dimethyl sulfide, dimethyl sulfoxide, dimethyl sulfone, CS 2 , FeS 2 , and even elemental sulfur. Strain SY1 metabolized DBT to dibenzothiophene-5-oxide, DBT sulfone, and 2-hydroxybiphenyl, which was subsequently nitrated to produce at least two different hydroxynitrobiphenyls during cultivation. These metabolites were separated by silica gel column chromatography and identified by nuclear magnetic resonance, UV, and mass spectral techniques. Resting cells of SY1 desulfurized toluenesulfonic acid and released sulfite anion. On the basis of these results, a new DBT degradation pathway is proposed

Pathogenicity of Cryptosporidium parvum - evaluation of an animal infection model

DEFF Research Database (Denmark)

Enemark, Heidi L.; Bille-Hansen, Vivi; Lind, Peter

2003-01-01

and rectum. The unintended presence of rotavirus in some of the experimental animals revealed an additive or synergistic effect between rotavirus and C. parvum as indicated by prolonged diarrhoea, increased oocyst shedding, decreased weight gain and elevated levels of serum haptoglobin and serum amyloid...... A (SAA) in piglets infected simultaneously with both pathogens. The difference in daily weight gain between infected and control animals was significant only for piglets co-infected with rotavirus. The acute phase response of haptoglobin and SAA was characterised by a large individual variation....... In piglets, co-infected with rotavirus, the levels of serum haptoglobin were 3.5 and 4.6 times higher in the infected versus the controls 6 and 9 dpi, respectively (mean values: 2411 mug/ml +/- S.D. 2023 and 1840 mug/ml +/- S.D. 1697). In the controls infected with rotavirus, peak haptoglobin concentration...

Genome sequence of Corynebacterium pseudotuberculosis biovar equi strain 258 and prediction of antigenic targets to improve biotechnological vaccine production

DEFF Research Database (Denmark)

Soares, Siomar C; Trost, Eva; Ramos, Rommel T J

2013-01-01

Corynebacterium pseudotuberculosis is the causative agent of several veterinary diseases in a broad range of economically important hosts, which can vary from caseous lymphadenitis in sheep and goats (biovar ovis) to ulcerative lymphangitis in cattle and horses (biovar equi). Existing vaccines ag...

Cystic Neutrophilic Granulomatous Mastitis: Further Characterization of a Distinctive Histopathologic Entity Not Always Demonstrably Attributable to Corynebacterium Infection.

Science.gov (United States)

D'Alfonso, Timothy M; Moo, Tracy-Ann; Arleo, Elizabeth K; Cheng, Esther; Antonio, Lilian B; Hoda, Syed A

2015-10-01

Granulomatous lobular mastitis (GLM) is an uncommon condition that typically occurs in parous, reproductive-aged women and can simulate malignancy on the basis of clinical and imaging features. A distinctive histologic pattern termed cystic neutrophilic granulomatous mastitis (CNGM) is seen in some cases of GLM and has been associated with Corynebacterium infection. We sought to further characterize the clinical, imaging, and histopathologic features of CNGM by studying 12 cases and attempted to establish the relationship of this disease with Corynebacterium infection. Patients were women ranging in age from 25 to 49 years (median: 34 y), and all presented with a palpable mass that was painful in half of the cases. In 2 of 9 cases, imaging was highly suspicious for malignancy (BI-RADS 5). CNGM was characterized by lobulocentric granulomas with mixed inflammation and clear vacuoles lined by neutrophils within granulomas. Gram-positive bacilli were identified in 5/12 cases. In 4 patients, the disease process worsened after the diagnostic core biopsy, with the development of a draining sinus in 2 cases. No growth of bacteria was seen in any microbial cultures. No bacterial DNA was identified by 16S rDNA polymerase chain reaction for 1 case that showed gram-positive bacilli on histology. Patients were treated with variable combinations of surgery, antibiotics, and steroids. The time to significant resolution of symptoms ranged from 2 weeks to 6 months. Similar to other forms of GLM, CNGM can mimic malignancy clinically and on imaging. When encountered in a needle core biopsy sample, recognition of the characteristic histologic pattern and its possible association with Corynebacterium infection can help guide treatment.

Neofusicoccum parvum Colonization of the Grapevine Woody Stem Triggers Asynchronous Host Responses at the Site of Infection and in the Leaves

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Mélanie Massonnet

2017-06-01

Full Text Available Grapevine trunk diseases cause important economic losses in vineyards worldwide. Neofusicoccum parvum, one of the most aggressive causal agents of the trunk disease Botryosphaeria dieback, colonizes cells and tissues of the grapevine wood, leading to the formation of an internal canker. Symptoms then extend to distal shoots, with wilting of leaves and bud mortality. Our aim was to characterize the transcriptional dynamics of grapevine genes in the woody stem and in the leaves during Neofusicoccum parvum colonization. Genome-wide transcriptional profiling at seven distinct time points (0, 3, and 24 hours; 2, 6, 8, and 12 weeks showed that both stems and leaves undergo extensive transcriptomic reprogramming in response to infection of the stem. While most intense transcriptional responses were detected in the stems at 24 hours, strong responses were not detected in the leaves until the next sampling point at 2 weeks post-inoculation. Network co-expression analysis identified modules of co-expressed genes common to both organs and showed most of these genes were asynchronously modulated. The temporal shift between stem vs. leaf responses affected transcriptional modulation of genes involved in both signal perception and transduction, as well as downstream biological processes, including oxidative stress, cell wall rearrangement and cell death. Promoter analysis of the genes asynchronously modulated in stem and leaves during N. parvum colonization suggests that the temporal shift of transcriptional reprogramming between the two organs might be due to asynchronous co-regulation by common transcriptional regulators. Topology analysis of stem and leaf co-expression networks pointed to specific transcription factor-encoding genes, including WRKY and MYB, which may be associated with the observed transcriptional responses in the two organs.

Corynebacterium glutamicum for Sustainable Bioproduction: From Metabolic Physiology to Systems Metabolic Engineering.

Science.gov (United States)

Becker, Judith; Gießelmann, Gideon; Hoffmann, Sarah Lisa; Wittmann, Christoph

Since its discovery 60 years ago, Corynebacterium glutamicum has evolved into a workhorse for industrial biotechnology. Traditionally well known for its remarkable capacity to produce amino acids, this Gram-positive soil bacterium, has become a flexible, efficient production platform for various bulk and fine chemicals, materials, and biofuels. The central turnstile of all these achievements is our excellent understanding of its metabolism and physiology. This knowledge base, together with innovative systems metabolic engineering concepts, which integrate systems and synthetic biology into strain engineering, has upgraded C. glutamicum into one of the most successful industrial microorganisms in the world.

First report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus).

Science.gov (United States)

Oliveira, Manuela; Barroco, Cynthia; Mottola, Carla; Santos, Raquel; Lemsaddek, Abdelhak; Tavares, Luis; Semedo-Lemsaddek, Teresa

2014-09-21

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis, a common disease in small ruminant populations throughout the world and responsible for a significant economic impact for producers. To our knowledge, this is the first characterization of C. pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus). In this study, phenotypic and genotypic identification methods allocated the swine isolates in C. pseudotuberculosis biovar ovis. The vast majority of the isolates were able to produce phospholipase D and were susceptible to most of the antimicrobial compounds tested. Macrorestriction patterns obtained by Pulsed Field Gel Electrophoresis (PFGE) grouped the C. pseudotuberculosis in two clusters with a high similarity index, which reveals their clonal relatedness. Furthermore, swine isolates were compared with C. pseudotuberculosis from caprines and PFGE patterns also showed high similarity, suggesting the prevalence of dominant clones and a potential cross-dissemination between these two animal hosts. This work represents the first report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig and alerts for the importance of the establishment of suitable control and sanitary management practices to control the infection and avoid further dissemination of this important pathogen to other animal hosts.

Rational Design of a Corynebacterium glutamicum Pantothenate Production Strain and Ins Characterization by Metabolic Flux Analysis and Genome-Wide Transcriptional Profiling

Czech Academy of Sciences Publication Activity Database

Hüser, A.T.; Chassagnole, Ch.; Lindley, N.D.; Merkamm, M.; Guyonvarch, A.; Elišáková, Veronika; Pátek, Miroslav; Kalinowski, J.; Brune, I.; Pühler, A.; Tauch, A.

2005-01-01

Roč. 71, č. 6 (2005), s. 3255-3268 ISSN 0099-2240 Institutional research plan: CEZ:AV0Z50200510 Keywords : corynebacterium glutamicum * metabolic flux Subject RIV: EE - Microbiology, Virology Impact factor: 3.818, year: 2005

Pyruvate:Quinone Oxidoreductase in Corynebacterium glutamicum: Molecular Analysis of the pqo Gene, Significance of the Enzyme, and Phylogenetic Aspects

Czech Academy of Sciences Publication Activity Database

Schreiner, M. E.; Riedel, Ch.; Holátko, Jiří; Pátek, Miroslav; Eikmanns, B. J.

2006-01-01

Roč. 188, č. 4 (2006), s. 1341-1350 ISSN 0021-9193 R&D Projects: GA ČR GA525/04/0548 Institutional research plan: CEZ:AV0Z50200510 Keywords : corynebacterium glutamicum * pqo * molecular analysis Subject RIV: EE - Microbiology, Virology Impact factor: 3.993, year: 2006

The pan-genome of the animal pathogen Corynebacterium pseudotuberculosis reveals differences in genome plasticity between the biovar ovis and equi strains

DEFF Research Database (Denmark)

Soares, Siomar C; Silva, Artur; Trost, Eva

2013-01-01

, Corynebacterium pseudotuberculosis infections pose a rising worldwide economic problem in ruminants. The complete genome sequences of 15 C. pseudotuberculosis strains isolated from different hosts and countries were comparatively analyzed using a pan-genomic strategy. Phylogenomic, pan-genomic, core genomic...

Disinfection and toxicological assessments of pulsed UV and pulsed-plasma gas-discharge treated-water containing the waterborne protozoan enteroparasite Cryptosporidium parvum.

Science.gov (United States)

Hayes, Jennifer; Kirf, Dominik; Garvey, Mary; Rowan, Neil

2013-09-01

We report for the first time on the comparative use of pulsed-plasma gas-discharge (PPGD) and pulsed UV light (PUV) for the novel destruction of the waterborne enteroparasite Cryptosporidium parvum. It also describes the first cyto-, geno- and ecotoxicological assays undertaken to assess the safety of water decontaminated using PPGD and PUV. During PPGD treatments, the application of high voltage pulses (16 kV, 10 pps) to gas-injected water (N2 or O2, flow rate 2.5L/min) resulted in the formation of a plasma that generated free radicals, ultraviolet light, acoustic shock waves and electric fields that killed ca. 4 log C. parvum oocysts in 32 min exposure. Findings showed that PPGD-treated water produced significant cytotoxic properties (as determined by MTT and neutral red assays), genotoxic properties (as determined by comet and Ames assays), and ecotoxic properties (as determined by Microtox™, Thamnotox™ and Daphnotox™ assays) that are representative of different trophic levels in aquatic environment (pozone (0.8 mg/L) and/or dissociated nitric and nitrous acid that contributed to the observed disinfection and toxicity. Chemical analysis of PPGD-treated water revealed increasing levels of electrode metals that were present at ≤ 30 times the tolerated respective values for EU drinking water. PUV-treated water did not exhibit any toxicity and was shown to be far superior to that of PPGD for killing C. parvum oocysts taking only 90 s of pulsing [UV dose of 6.29 μJ/cm(2)] to produce a 4-log reduction compared to a similar reduction level achieved after 32min PPGD treatment as determined by combined in vitro CaCo-2 cell culture-qPCR. © 2013. Published by Elsevier B.V. All rights reserved.

BIOCHEMICAL AND PHYLOGENETIC STUDIES OF CreD OF Corynebacterium glutamicum

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Muhammad Tausif Chaudhry

2015-06-01

Full Text Available CreD characterized as Mg2+-dependent phosphohydrolase with conserved HD domain was involved in 4-cresol metabolism in Corynebacterium glutamicum. Native molecular mass of 54 kDa suggested that the biological unit is a dimer. No deoxynucleotide triphosphate triphosphohydrolase (dNTPase activity was detected for CreD. The apparent Km and Vmax values for 4-nitrophenyl phosphate were 0.35 mM and 16.23 M min-1 mg-1, respectively, while calculated values for kcat and kcat/Km were 0.4 s-1 and 1.14103 M-1 s-1, respectively. Among thiol group inhibitors, iodoacetic acid significantly inhibited phosphohydrolase activity. Sequence identity and phylogenetic analysis suggested universal existence of CreD homologues. Involvement of HD-domain hydrolase in aromatic degradation has not been reported before.

Production of L-valine from metabolically engineered Corynebacterium glutamicum.

Science.gov (United States)

Wang, Xiaoyuan; Zhang, Hailing; Quinn, Peter J

2018-05-01

L-Valine is one of the three branched-chain amino acids (valine, leucine, and isoleucine) essential for animal health and important in metabolism; therefore, it is widely added in the products of food, medicine, and feed. L-Valine is predominantly produced through microbial fermentation, and the production efficiency largely depends on the quality of microorganisms. In recent years, continuing efforts have been made in revealing the mechanisms and regulation of L-valine biosynthesis in Corynebacterium glutamicum, the most utilitarian bacterium for amino acid production. Metabolic engineering based on the metabolic biosynthesis and regulation of L-valine provides an effective alternative to the traditional breeding for strain development. Industrially competitive L-valine-producing C. glutamicum strains have been constructed by genetically defined metabolic engineering. This article reviews the global metabolic and regulatory networks responsible for L-valine biosynthesis, the molecular mechanisms of regulation, and the strategies employed in C. glutamicum strain engineering.

Non-specific immunization against parasites

International Nuclear Information System (INIS)

Cox, F.E.G.

1981-01-01

Non-specific resistance to tumours can be induced by pretreating animals with micro-organisms, microbial extracts or various synthetic substances. Mycobacterium bovis, Corynebacterium parvum and a number of other micro-organisms also protect mice against rodent piroplasms and there is evidence that they are also protective against other parasites including Schistosoma mansoni. The actual mechanisms of non-specific immunity are still unclear but it is influenced by both the genetic make-up of the host and the nature of the parasite. Non-specific immunization may be a possible alternative to specific immunization and may avoid many of the potential immunopathological changes induced during parasite infections. Irradiated vaccines (Dictyocaulus viviparus, schistomiasis) are mentioned marginally only

Toxigenic Corynebacterium ulcerans isolated from a free-roaming red fox (Vulpes vulpes).

Science.gov (United States)

Sting, Reinhard; Ketterer-Pintur, Sandra; Contzen, Matthias; Mauder, Norman; Süss-Dombrowski, Christine

2015-01-01

Corynebacterium (C.) ulcerans could be isolated from the spleen of a red fox (Vulpes vulpes) that had been found dead in the state of Baden-Württemberg, Germany. Pathohistological examination suggested that the fox had died of distemper, as was confirmed by PCR. The isolate was identified biochemically, by MALDI-TOF MS, FT-IR and by partial 16S rRNA, rpoB and tox gene sequencing. Using the Elek test the C. ulcerans isolate demonstrated diphtheria toxin production. FT-IR and sequencing data obtained from the C. ulcerans isolate from the red fox showed higher similarity to isolates from humans than to those from wild game.

Ureaplasma parvum causing life-threatening disease in a susceptible patient.

Science.gov (United States)

Korytny, Alexander; Nasser, Roni; Geffen, Yuval; Friedman, Tom; Paul, Mical; Ghanem-Zoubi, Nesrin

2017-08-16

A 56-year-old man with lymphoma developed orchitis followed by septic arthritis of his right glenohumeral joint. Synovial fluid cultures were negative but PCR amplification test was positive for Ureaplasmaparvum. The patient was treated with doxycycline. Two and a half years later, the patient presented with shortness of breath and grade III/IV diastolic murmur on auscultation. Echocardiography revealed severely dilated left heart chambers, severe aortic regurgitation and several mobile masses on the aortic valve cusps suspected to be vegetations. He underwent valve replacement; valve tissue culture was negative but the 16S rRNA gene amplification test was positive for U. parvum He was treated again with doxycycline. In an outpatient follow-up 1 year and 3 months later, the patient was doing well. Repeated echocardiography showed normal aortic prosthesis function. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Pathogenicity and genetic variation of 3 strains of Corynebacterium bovis in immunodeficient mice.

Science.gov (United States)

Dole, Vandana S; Henderson, Kenneth S; Fister, Richard D; Pietrowski, Michael T; Maldonado, Geomaris; Clifford, Charles B

2013-07-01

Corynebacterium bovis has been associated with hyperkeratotic dermatitis and acanthosis in mice. We studied 3 different strains of C. bovis: one previously described to cause hyperkeratotic dermatitis (HAC), one that infected athymic nude mice without leading to the classic clinical signs, and one of bovine origin (ATCC 7715). The 3 strains showed a few biochemical and genetic differences. Immunodeficient nude mice were housed in 3 independent isolators and inoculated with pure cultures of the 3 strains. We studied the transmission of these C. bovis studies to isolator-bedding and contact sentinels housed for 5 to 12 wk in filter-top or wire-top cages in the respective isolators. Using a 16S rRNA-based qPCR assay, we did not find consistent differences in growth and transmission among the 3 C. bovis strains, and neither the incidence nor severity of hyperkeratosis or acanthosis differed between strains. Housing in filter-top compared with wire-top cages did not alter the morbidity associated with any of the strains. Our findings confirmed the variability in the gross and histologic changes associated with C. bovis infection of mice. Although bacteriology was a sensitive method for the detection of Corynebacterium spp., standard algorithms occasionally misidentified C. bovis and several related species. Our study demonstrates that PCR of skin swabs or feces is a sensitive and specific method for the detection of C. bovis infection in mice. An rpoB-based screen of samples from North American vivaria revealed that HAC is the predominant C. bovis strain in laboratory mice.

PcaO Positively Regulates pcaHG of the β-Ketoadipate Pathway in Corynebacterium glutamicum▿

OpenAIRE

Zhao, Ke-Xin; Huang, Yan; Chen, Xi; Wang, Nan-Xi; Liu, Shuang-Jiang

2010-01-01

We identified a new regulator, PcaO, which is involved in regulation of the protocatechuate (PCA) branch of the β-ketoadipate pathway in Corynebacterium glutamicum. PcaO is an atypical large ATP-binding LuxR family (LAL)-type regulator and does not have a Walker A motif. A mutant of C. glutamicum in which pcaO was disrupted (RES167ΔpcaO) was unable to grow on PCA, and growth on PCA was restored by complementation with pcaO. Both an enzymatic assay of PCA 3,4-dioxygenase activity (encoded by p...

ORF Sequence: NC_003450 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available lase [Corynebacterium glutamicum ATCC 13032] MTVRPIVIHGDPVLHNPTQLVTEDVSELQELIADMYETMDVANGVGLAANQIGVSKRIFVYDCPDDEGVMHKGCFINPVLETSEIPET...MPADDGSDEEGCLSVPGEGFPTGRAHWAKVTGLNEKGEEVSVEAEGFLARCFQHEVGHLDGFLYTDVLIGRWKRMAKKAIKANGWTEPGLTWMPGEDEDPFGHDA

Diphtheria in the Republic of Georgia: Use of Molecular Typing Techniques for Characterization of Corynebacterium diphtheriae Strains

Science.gov (United States)

Sulakvelidze, Alexander; Kekelidze, Merab; Gomelauri, Tsaro; Deng, Yingkang; Khetsuriani, Nino; Kobaidze, Ketino; De Zoysa, Aruni; Efstratiou, Androulla; Morris, J. Glenn; Imnadze, Paata

1999-01-01

Sixty-six Corynebacterium diphtheriae strains (62 of the gravis biotype and 4 of the mitis biotype) isolated during the Georgian diphtheria epidemic of 1993 to 1998 and 13 non-Georgian C. diphtheriae strains (10 Russian and 3 reference isolates) were characterized by (i) biotyping, (ii) toxigenicity testing with the Elek assay and PCR, (iii) the randomly amplified polymorphic DNA (RAPD) technique, and (iv) pulsed-field gel electrophoresis (PFGE). Fifteen selected strains were ribotyped. Six RAPD types and 15 PFGE patterns were identified among all strains examined, and 12 ribotypes were found among the 15 strains that were ribotyped. The Georgian epidemic apparently was caused by one major clonal group of C. diphtheriae (PFGE type A, ribotype R1), which was identical to the predominant epidemic strain(s) isolated during the concurrent diphtheria epidemic in Russia. A dendrogram based on the PFGE patterns revealed profound differences between the minor (nonpredominant) epidemic strains found in Georgia and Russia. The methodologies for RAPD typing, ribotyping, and PFGE typing of C. diphtheriae strains were improved to enable rapid and convenient molecular typing of the strains. The RAPD technique was adequate for biotype differentiation; however, PFGE and ribotyping were better (and equal to each other) at discriminating between epidemiologically related and unrelated isolates. PMID:10488190

Antimicrobial activity of Manuka honey against antibiotic-resistant strains of the cell wall-free bacteria Ureaplasma parvum and Ureaplasma urealyticum.

Science.gov (United States)

Hillitt, K L; Jenkins, R E; Spiller, O B; Beeton, M L

2017-03-01

The susceptibility of the cell wall-free bacterial pathogens Ureaplasma spp. to Manuka honey was examined. The minimum inhibitory concentration (MIC) of Manuka honey for four Ureaplasma urealyticum and four Ureaplasma parvum isolates was determined. Sensitivity to honey was also compared to clinical isolates with resistance to tetracycline, macrolide and fluoroquinolone antibiotics. Finally step-wise resistance training was utilized in an attempt to induce increased tolerance to honey. The MIC was dependent on the initial bacterial load with 7·5 and 18·0% w/v honey required to inhibit U. urealyticum at 1 and 10 6 colour changing units (CCU), respectively, and 4·8 and 15·3% w/v required to inhibit U. parvum at 1 and 10 6  CCU respectively. MIC values were consistently lower for U. parvum compared with U. urealyticum. Antimicrobial activity was seen against tetracycline-resistant, erythromycin-resistant and ciprofloxacin-resistant isolates at 10 5  CCU. No resistance to honey was observed with 50 consecutive challenges at increasing concentrations of honey. This is the first report of the antimicrobial activity of Manuka honey against a cell wall-free bacterial pathogen. The antimicrobial activity was retained against antibiotic-resistant strains and it was not possible to generate resistant mutants. Manuka honey is known to have a broad spectrum of antimicrobial activity, with the bacterial cell wall being suggested as a predominant site of action. This study has demonstrated that Manuka honey has activity against Ureaplasma spp., a genus of cell wall-free bacteria which are intrinsically resistant to many available antibiotics making treatment inherently difficult. This is the first report of the antimicrobial activity of Manuka honey against a bacterial pathogen, in the absence of a cell well and opens scope for the use of components of Manuka honey as a therapeutic among Ureaplasma infections. © 2016 The Society for Applied Microbiology.

Molecular characterization of Cryptosporidium parvum and Cryptosporidium hominis GP60 subtypes worldwide

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Catalina Avendaño V

2017-09-01

Full Text Available Cryptosporidium is a zoonotic parasite very important in animal health as well as in public health. It is because this is one of the main causes of diarrhea in children, calves, lambs and other variety of youth mammalians in a lot of countries. The globalization has enabled the exchange of biological material in different regions worldwide, encouraging the spread of diseases and exposure to these biological agents to different environmental conditions, inducing adaptation through genetic changes. Based in the polymorphism of the gene for GP60, this review intended to present the distribution of Cryptosporidium parvum and Cryptosporidium hominis in humans and calves worldwide. The subtype that affects cattle more frequently corresponds to IIaA15G2R; while the subtype most frequently isolated from human samples is IaA19G2.

Transport of Cryptosporidium parvum Oocysts in a Silicon Micromodel

Energy Technology Data Exchange (ETDEWEB)

Liu, Yuanyuan; Zhang, Changyong; Hilpert, Markus; Kuhlenschmidt, Mark S.; Kuhlenschmidt, Theresa B.; Nguyen, Thanh H.

2012-02-01

Effective removal of Cryptosporidium parvum oocysts by granular filtration requires the knowledge of oocyst transport and deposition mechanisms, which can be obtained based on real time microscopic observation of oocyst transport in porous media. Attachment of oocysts to silica surface in a radial stagnation point flow (RSPF) cell and in a micromodel, which has 2-dimensional (2-D) microscopic pore structures consisting of an array of cylindrical collectors, was studied and compared. Real time transport of oocysts in the micromodel was recorded to determine the attached oocyst distributions in transversal and longitudinal directions. In the micromodel, oocysts attached to the forward portion of clean collectors, where the flow velocity was lowest. After initial attachment, oocysts attached onto already attached oocysts. As a result, the collectors ripened and the region available for flow was reduced. Results of attachment and detachment experiments suggest that surface charge heterogeneity allowed for oocyst attachment. In addition to experiments, Lattice-Boltzmann simulations helped understanding the slightly non-uniform flow field and explained differences in the removal efficiency in the transversal direction. However, the hydrodynamic modeling could not explain differences in attachment in the longitudinal direction.

Global Transcriptomic Analysis of the Response of Corynebacterium glutamicum to Vanillin.

Science.gov (United States)

Chen, Can; Pan, Junfeng; Yang, Xiaobing; Guo, Chenghao; Ding, Wei; Si, Meiru; Zhang, Yi; Shen, Xihui; Wang, Yao

2016-01-01

Lignocellulosic biomass is an abundant and renewable resource for biofuels and bio-based chemicals. Vanillin is one of the major phenolic inhibitors in biomass production using lignocellulose. To assess the response of Corynebacterium glutamicum to vanillin stress, we performed a global transcriptional response analysis. The transcriptional data showed that the vanillin stress not only affected the genes involved in degradation of vanillin, but also differentially regulated several genes related to the stress response, ribosome/translation, protein secretion, and the cell envelope. Moreover, deletion of the sigH or msrA gene in C. glutamicum resulted in a decrease in cell viability under vanillin stress. These insights will promote further engineering of model industrial strains, with enhanced tolerance or degradation ability to vanillin to enable suitable production of biofuels and bio-based chemicals from lignocellulosic biomass.

Recurrent Breast Abscesses due to Corynebacterium kroppenstedtii, a Human Pathogen Uncommon in Caucasian Women

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Anne Le Flèche-Matéos

2012-01-01

Full Text Available Background. Corynebacterium kroppenstedtii (Ck was first described in 1998 from human sputum. Contrary to what is observed in ethnic groups such as Maori, Ck is rarely isolated from breast abscesses and granulomatous mastitis in Caucasian women. Case Presentation. We herein report a case of recurrent breast abscesses in a 46-year-old Caucasian woman. Conclusion. In the case of recurrent breast abscesses, even in Caucasian women, the possible involvement of Ck should be investigated. The current lack of such investigations, probably due to the difficulty to detect Ck, may cause the underestimation of such an aetiology.

APLICACION DE TECNICAS DE INGENIERIA METABOLICA AL MEJORAMIENTO DE LA PRODUCCION DE TREHALOSA POR CORYNEBACTERIUM GLUTAMICUM.

OpenAIRE

PADILLA IGLESIAS, LEANDRO MAURICIO

2004-01-01

La Trehalosa es un disacárido con tremendas aplicaciones en la industria biotecnológica y alimenticia. Este compuesto se encuentra en muchos organismos, a causa de su capacidad de proteger las células contra el calor y la deshidratación. Un ejemplo, es la bacteria Gram-positiva Corynebacterium glutamicum, la cual sintetiza trehalosa a través de dos rutas principales, TreYZ y OtsBA, usando ADP-glucosa (especulativamente) y UDP-glucosa, respectivamente, como dadores de unidades de ...

ORF Sequence: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_002162 gi|13358146 >gi|13358146|ref|NP_078420.1| transcription antitermination factor [Ureap...lasma parvum serovar 3 str. ATCC 700970] MAYKIKDLDSKLLSDLKIDFNHRHQWYIVTVVSGNEQKVIENIKDKLNGYGYGDKLSDLKIIKEKIKEVKIYEPSEAP

Radioprotective action of endoneous and exogenous natural compounds

International Nuclear Information System (INIS)

Del Mastro, N.L.

1991-04-01

In last years at the Radiobiology Division of our Institute several studies have been performed to determine the radioprotective capacity of some natural products from microbial, vegetal or endogenous origin. This substances have been chosen for some of their specific biological characteristics, among them: immunoestimulating (bacillus of Calmette-Guerin, Corynebacterium parvum), anti-inflammatory (Cordia verbanacea), anti-carcinogenic and anti-oxidant ones (α-tocopherol). Assays were performed using albino mice previously injected intraperitoneally with those agents and then irradiated with lethal doses of sup(60)Co gamma radiation. Survival and body weight curves after irradiation have been studied during 30 days comparing to normal controls. Depending on the specific properties of tested substances the induction of splenomegalia and the behavior of peritoneal cellularity were concomitantly analyzed. (author)

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).

ORF Sequence: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_002162 gi|13357802 >gi|13357802|ref|NP_078076.1| ribosomal protein L24 [Ureapla...sma parvum serovar 3 str. ATCC 700970] MNRIKKGDTVVVISGKNKNKSGVVIQVNPKEQTALVEGVNKIKRHQKKDQTHEQSGIIEKEAPIRLCKLALVDPKGKDKGKATKVKYLLKDNKKVRVARKSGSELDVNKK

Global Transcriptomic Analysis of the Response of Corynebacterium glutamicum to Vanillin.

Directory of Open Access Journals (Sweden)

Can Chen

Full Text Available Lignocellulosic biomass is an abundant and renewable resource for biofuels and bio-based chemicals. Vanillin is one of the major phenolic inhibitors in biomass production using lignocellulose. To assess the response of Corynebacterium glutamicum to vanillin stress, we performed a global transcriptional response analysis. The transcriptional data showed that the vanillin stress not only affected the genes involved in degradation of vanillin, but also differentially regulated several genes related to the stress response, ribosome/translation, protein secretion, and the cell envelope. Moreover, deletion of the sigH or msrA gene in C. glutamicum resulted in a decrease in cell viability under vanillin stress. These insights will promote further engineering of model industrial strains, with enhanced tolerance or degradation ability to vanillin to enable suitable production of biofuels and bio-based chemicals from lignocellulosic biomass.

Transcriptional Analysis of the groES-groEL1, groEL2, and dnaK genes in Corynebacterium glutamicum: Characterization of Heat Shock-Induced Promoters

Czech Academy of Sciences Publication Activity Database

Barreiro, C.; González-Lavado, E.; Pátek, Miroslav; Martin, J. F.

2004-01-01

Roč. 186, č. 14 (2004), s. 4813-4817 ISSN 0021-9193 R&D Projects: GA AV ČR KSK5052113 Keywords : corynebacterium glutamicum * mrna Subject RIV: EE - Microbiology, Virology Impact factor: 4.146, year: 2004

Bioconversion of sugar cane molasses into glutamic acid by gamma irradiated corynebacterium glutamicum

International Nuclear Information System (INIS)

El-Batal, A.I.

1996-01-01

Corynebacterium glutamicum (ATCC 13058) was used for glutamic acid production from sugar cane molasses which contain sufficient. The addition of 5 units ml 4 of penicillin G was superior in glutamic acid production (11.5 g L 4 ). Tweens and their saturated fatty acids were effective on the accumulation of glutamic acid in the culture medium and the maximum yield (16.6 g L 4 ) was the addition of 5 mg ml 4 Tween 40. Gamma irradiation prior to Tween-40 treatment of bacterial cells resulted in an obvious increase in glutamic acid production and it was maximum (23.72 g L 4 ) at 0.1 k Gy exposure dose of inocula. 5 tabs

ORF Alignment: NC_002935 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... [Corynebacterium diphtheriae] ... Length = 91 ... Query: 15 ... ILTPAQERVAQAIARLGPEISLTDISRMVGGH...PNASRQHIKTLENSGYISATQKRGAAGR 74 ... ILTPAQERVAQAIARLGPEISLTDISRMVGGHPNASRQ...HIKTLENSGYISATQKRGAAGR Sbjct: 1 ... ILTPAQERVAQAIARLGPEISLTDISRMVGGHPNASRQHIKTLENSGYISATQKRGAAGR 60 ...

Prediction of DtxR regulon: Identification of binding sites and operons controlled by Diphtheria toxin repressor in Corynebacterium diphtheriae

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Hasnain Seyed

2004-09-01

Full Text Available Abstract Background The diphtheria toxin repressor, DtxR, of Corynebacterium diphtheriae has been shown to be an iron-activated transcription regulator that controls not only the expression of diphtheria toxin but also of iron uptake genes. This study aims to identify putative binding sites and operons controlled by DtxR to understand the role of DtxR in patho-physiology of Corynebacterium diphtheriae. Result Positional Shannon relative entropy method was used to build the DtxR-binding site recognition profile and the later was used to identify putative regulatory sites of DtxR within C. diphtheriae genome. In addition, DtxR-regulated operons were also identified taking into account the predicted DtxR regulatory sites and genome annotation. Few of the predicted motifs were experimentally validated by electrophoretic mobility shift assay. The analysis identifies motifs upstream to the novel iron-regulated genes that code for Formamidopyrimidine-DNA glycosylase (FpG, an enzyme involved in DNA-repair and starvation inducible DNA-binding protein (Dps which is involved in iron storage and oxidative stress defense. In addition, we have found the DtxR motifs upstream to the genes that code for sortase which catalyzes anchoring of host-interacting proteins to the cell wall of pathogenic bacteria and the proteins of secretory system which could be involved in translocation of various iron-regulated virulence factors including diphtheria toxin. Conclusions We have used an in silico approach to identify the putative binding sites and genes controlled by DtxR in Corynebacterium diphtheriae. Our analysis shows that DtxR could provide a molecular link between Fe+2-induced Fenton's reaction and protection of DNA from oxidative damage. DtxR-regulated Dps prevents lethal combination of Fe+2 and H2O2 and also protects DNA by nonspecific DNA-binding. In addition DtxR could play an important role in host interaction and virulence by regulating the levels of sortase

Generation of T-cells reactive to the poorly immunogenic B16-BL6 melanoma with efficacy in the treatment of spontaneous metastases.

Science.gov (United States)

Geiger, J D; Wagner, P D; Cameron, M J; Shu, S; Chang, A E

1993-04-01

The B16-BL6 (BL6) melanoma is a poorly immunogenic murine tumor that is highly invasive and spontaneously metastasizes from the primary site. Utilizing an established anti-CD3/interleukin-2 (IL-2) culture procedure, we have previously reported that lymph nodes (LNs) draining immunogenic murine sarcomas contained preeffector cells that could be activated to differentiate into therapeutic effector cells for adoptive immunotherapy. By contrast, LNs draining the poorly immunogenic BL6 melanoma were found not to be a reliable source of preeffector cells. Instead, sensitization of preeffector cells reactive to BL6 required the subcutaneous inoculation of tumor admixed with Corynebacterium parvum. LN cells draining these vaccination sites demonstrated therapeutic efficacy only after subsequent anti-CD3/IL-2 activation. The sensitization of preeffector cells was dependent on the presence of tumor antigen and an optimal dose of C. parvum ( 140 days. All mice except one that received no treatment or was treated with IL-2 alone succumbed to visceral metastases with an MST of approximately 23 days. This study characterizes a model whereby the weak immune response to the BL6 melanoma can be positively or negatively modulated for the generation of antitumor reactive T-cells useful in adoptive immunotherapy.

Dual production of poly(3-hydroxybutyrate) and glutamate using variable biotin concentrations in Corynebacterium glutamicum.

Science.gov (United States)

Jo, Sung-Jin; Leong, Chean Ring; Matsumoto, Ken'ichiro; Taguchi, Seiichi

2009-04-01

We previously synthesized poly(3-hydroxybutyrate) [P(3HB)] in recombinant Corynebacterium glutamicum, a prominent producer of amino acids. In this study, a two-step cultivation was established for the dual production of glutamate and P(3HB) due to the differences in the optimal concentration of biotin. Glutamate was extracellularly produced first under the biotin-limited condition of 0.3 microg/L. Production was then shifted to P(3HB) by addition of biotin to a total concentration of 9 microg/L. The final products obtained were 18 g/L glutamate and 36 wt% of P(3HB).

ORF Alignment: NC_002935 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available in ... [Corynebacterium diphtheriae] ... Length = 134 ... Query: 4 ... RQVEYKGVHFFPPEDDACLVFSWSERRR...ILPIWVDVEEGIRLSERSEHGAPRRPLAHDVL 63 ... RQVEYKGVHFFPPEDDACLVFSWSERRRILPIWV...DVEEGIRLSERSEHGAPRRPLAHDVL Sbjct: 1 ... RQVEYKGVHFFPPEDDACLVFSWSERRRILPIWVDVEEGIRLSERSEHGAPRRPLAHDVL 60 ... Query

ORF Alignment: NC_004369 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... [Corynebacterium efficiens YS-314] ... Length = 106 ... Query: 1 ... MSIVKINAISVPEGAGPELEKRFAARKQAIDS...QPGFEGFQLLRPVAGEDRYFVVTRWADE 60 ... MSIVKINAISVPEGAGPELEKRFAARKQAIDSQPGF...EGFQLLRPVAGEDRYFVVTRWADE Sbjct: 1 ... MSIVKINAISVPEGAGPELEKRFAARKQAIDSQPGFEGFQLLRPVAGEDRYFVVTRWADE 60 ...

ORF Alignment: NC_002935 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available tein ... [Corynebacterium diphtheriae] ... Length = 153 ... Query: 139 PAIPDDGPEIIVMTHPLDNVSEIDDV...HAEFLDQPDDDWLELYHFRGKALPRHALELLRTT 198 ... PAIPDDGPEIIVMTHPLDNVSEIDDVHAEFL...DQPDDDWLELYHFRGKALPRHALELLRTT Sbjct: 1 ... PAIPDDGPEIIVMTHPLDNVSEIDDVHAEFLDQPDDDWLELYHFRGKALPRHALELLRTT 60 ... Qu

Monoclonal Antibodies to Intracellular Stages of Cryptosporidium parvum Define Life Cycle Progression In Vitro.

Science.gov (United States)

Wilke, Georgia; Ravindran, Soumya; Funkhouser-Jones, Lisa; Barks, Jennifer; Wang, Qiuling; VanDussen, Kelli L; Stappenbeck, Thaddeus S; Kuhlenschmidt, Theresa B; Kuhlenschmidt, Mark S; Sibley, L David

2018-06-27

Among the obstacles hindering Cryptosporidium research is the lack of an in vitro culture system that supports complete life development and propagation. This major barrier has led to a shortage of widely available anti- Cryptosporidium antibodies and a lack of markers for staging developmental progression. Previously developed antibodies against Cryptosporidium were raised against extracellular stages or recombinant proteins, leading to antibodies with limited reactivity across the parasite life cycle. Here we sought to create antibodies that recognize novel epitopes that could be used to define intracellular development. We identified a mouse epithelial cell line that supported C. parvum growth, enabling immunization of mice with infected cells to create a bank of monoclonal antibodies (MAbs) against intracellular parasite stages while avoiding the development of host-specific antibodies. From this bank, we identified 12 antibodies with a range of reactivities across the parasite life cycle. Importantly, we identified specific MAbs that can distinguish different life cycle stages, such as trophozoites, merozoites, type I versus II meronts, and macrogamonts. These MAbs provide valuable tools for the Cryptosporidium research community and will facilitate future investigation into parasite biology. IMPORTANCE Cryptosporidium is a protozoan parasite that causes gastrointestinal disease in humans and animals. Currently, there is a limited array of antibodies available against the parasite, which hinders imaging studies and makes it difficult to visualize the parasite life cycle in different culture systems. In order to alleviate this reagent gap, we created a library of novel antibodies against the intracellular life cycle stages of Cryptosporidium We identified antibodies that recognize specific life cycle stages in distinctive ways, enabling unambiguous description of the parasite life cycle. These MAbs will aid future investigation into Cryptosporidium biology and

Mutations of the Corynebacterium glutamicum NCgl1221 Gene, Encoding a Mechanosensitive Channel Homolog, Induce l-Glutamic Acid Production▿

OpenAIRE

Nakamura, Jun; Hirano, Seiko; Ito, Hisao; Wachi, Masaaki

2007-01-01

Corynebacterium glutamicum is a biotin auxotroph that secretes l-glutamic acid in response to biotin limitation; this process is employed in industrial l-glutamic acid production. Fatty acid ester surfactants and penicillin also induce l-glutamic acid secretion, even in the presence of biotin. However, the mechanism of l-glutamic acid secretion remains unclear. It was recently reported that disruption of odhA, encoding a subunit of the 2-oxoglutarate dehydrogenase complex, resulted in l-gluta...

Cloning and Characterization of the Acidic Ribosomal Protein P2 of Cryptosporidium parvum, a New 17-Kilodalton Antigen▿

Science.gov (United States)

Priest, Jeffrey W.; Kwon, James P.; Montgomery, Joel M.; Bern, Caryn; Moss, Delynn M.; Freeman, Amanda R.; Jones, Cara C.; Arrowood, Michael J.; Won, Kimberly Y.; Lammie, Patrick J.; Gilman, Robert H.; Mead, Jan R.

2010-01-01

Cryptosporidium infection is commonly observed among children and immunocompromised individuals in developing countries, but large-scale outbreaks of disease among adults have not been reported. In contrast, outbreaks of cryptosporidiosis in the United States and Canada are increasingly common among patients of all ages. Thus, it seems likely that residents of regions where Cryptosporidium is highly endemic acquire some level of immunity, while residents of the developed world do not. A new immunodominant Cryptosporidium parvum antigen in the 15- to 17-kDa size range was identified as the Cryptosporidium parvum 60S acidic ribosomal protein P2 (CpP2). We developed a recombinant protein-based enzyme-linked immunosorbent assay for serologic population surveillance for antibodies that was 89% sensitive and 92% specific relative to the results of the large-format Western blot assay. The human IgG response is directed almost exclusively toward the highly conserved, carboxy-terminal 15 amino acids of the protein. Although IgG antibody cross-reactivity was documented with sera from patients with acute babesiosis, the development of an anti-CpP2 antibody response in our Peru study population correlated better with Cryptosporidium infection than with infection by any other parasitic protozoan. In Haiti, the prevalence of antibodies to CpP2 plateaus at 11 to 20 years of age. Because anti-CpP2 IgG antibodies were found only among residents of countries in the developing world where Cryptosporidium infection occurs early and often, we propose that this response may be a proxy for the intensity of infection and for acquired immunity. PMID:20410328

Use of immunomodulators in infectious diseases of domestic animals/ Uso de imunomoduladores nas enfermidades infecciosas dos animais domésticos

Directory of Open Access Journals (Sweden)

Jane Megid

2007-08-01

Full Text Available Immunomodulators are substances that act in the immune system providing, increase of the organic answer against microorganisms, including virus, bacteria and protozoa, by inducing the production of interferon and its inducers. There are a lot of situations in veterinary medicine where it is usefull to potencialize the immune response of individuals, mainly when is desired to increase the resistance to infections and the treatment of immunossupressing or multifactorials infectious diseases. In veterinary medicine some of more used immunomodulators are interferons and interferon inducers, interleukines, Baccilus of Calmett-Guérin (BCG and its derivated, Propionibacterium acnes (Corynebacterium parvum, mixed bacterial vaccine, PIND-ORF, Phosprenyl, Quillja Saponis, Bordetella pertussis, avridine and the levamizole. The present work review the available scientific literature, regarding the use of different immunomodulators in the prophylaxis and in the therapeutics of infectious diseases in domestic animals.Imunomoduladores são substâncias que atuam no sistema imunológico conferindo aumento da resposta orgânica contra determinados microorganismos, incluindo vírus, bactérias e protozoários, mediante à produção de interferon e seus indutores. Existem muitas situações na medicina veterinária em que se torna desejável potencializar a resposta imune, principalmente quando se pretende aumentar a resistência às infecções e no tratamento de enfermidades imunossupressoras ou de doenças infecciosas multifatorias, ou seja, nas quais vários agentes estão envolvidos e devido a isso, dificilmente obtêm-se sucesso no emprego de tratamentos convencionais. Na medicina veterinária alguns imunomoduladores utilizados são interferons , interleucinas, Bacilo de Calmett-Guérin (BCG e seus derivados, Propionibacterium acnes (Corynebacterium parvum, vacina bacteriana mista, PIND-ORF, Phosprenyl, Quillaja saponis, Bordetella pertussis, avridina e

AVALIAÇÃO DE FONTES DE CARBONO PARA A PRODUÇÃO DE INIBIDOR DE CRESCIMENTO DE Aspergillus fumigatus USP2 por Corynebacterium sp.

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Gabrielle Fernanda Zimmer

2013-07-01

Full Text Available O aumento significativo na incidência de infecções fúngicas invasivas e a resistência natural de agentes etiológicos a antifúngicos existentes têm motivado a constante pesquisa por novos agentes antifúngicos nos ultimos anos. Neste sentido, foi selcionada uma cepa de Corynebacterium sp. com potencial antagonista frente à Aspergilus fumigatus USP2. A cepa foi cultivada em fase submersa e em fase sólida, avaliando-se a variação das fontes de glicose, sacarose e glicerol em presença de peptona, bem como o meio sintético Czapek. Os caldos de cultivo submerso foram utilizados para o ensaio de antagonismo microbiano com o fungo Aspergillus fumigatus USP2. Os resultados apontam que o cultivo em fase sólida utilizando glicose como fonte de carbono apresenta maior potencial inibitório da cepa de Corynebacterium sp. sobre o fungo Aspergillus fumigatus USP2.

Ureaplasma parvum undergoes selection in utero resulting in genetically diverse isolates colonizing the chorioamnion of fetal sheep.

Science.gov (United States)

Dando, Samantha J; Nitsos, Ilias; Polglase, Graeme R; Newnham, John P; Jobe, Alan H; Knox, Christine L

2014-02-01

Ureaplasmas are the microorganisms most frequently isolated from the amniotic fluid of pregnant women and can cause chronic intrauterine infections. These tiny bacteria are thought to undergo rapid evolution and exhibit a hypermutatable phenotype; however, little is known about how ureaplasmas respond to selective pressures in utero. Using an ovine model of chronic intraamniotic infection, we investigated if exposure of ureaplasmas to subinhibitory concentrations of erythromycin could induce phenotypic or genetic indicators of macrolide resistance. At 55 days gestation, 12 pregnant ewes received an intraamniotic injection of a nonclonal, clinical Ureaplasma parvum strain followed by (i) erythromycin treatment (intramuscularly, 30 mg/kg/day, n = 6) or (ii) saline (intramuscularly, n = 6) at 100 days gestation. Fetuses were then delivered surgically at 125 days gestation. Despite injecting the same inoculum into all the ewes, significant differences between amniotic fluid and chorioamnion ureaplasmas were detected following chronic intraamniotic infection. Numerous polymorphisms were observed in domain V of the 23S rRNA gene of ureaplasmas isolated from the chorioamnion (but not the amniotic fluid), resulting in a mosaiclike sequence. Chorioamnion isolates also harbored the macrolide resistance genes erm(B) and msr(D) and were associated with variable roxithromycin minimum inhibitory concentrations. Remarkably, this variability occurred independently of exposure of ureaplasmas to erythromycin, suggesting that low-level erythromycin exposure does not induce ureaplasmal macrolide resistance in utero. Rather, the significant differences observed between amniotic fluid and chorioamnion ureaplasmas suggest that different anatomical sites may select for ureaplasma subtypes within nonclonal, clinical strains. This may have implications for the treatment of intrauterine ureaplasma infections.

Stimulation of innate immunity in newborn kids against Cryptosporidium parvum infection-challenge by intranasal/per-oral administration of liposomal formulation of N-L 18-norAbu-GMDP adjuvant

Czech Academy of Sciences Publication Activity Database

Turánek, J.; Kašná, A.; Koudela, Břetislav; Ledvina, Miroslav; Miller, A. D.

2005-01-01

Roč. 131, č. 5 (2005), s. 601-608 ISSN 0031-1820 R&D Projects: GA MZe QF3115 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z4055905 Keywords : Cryptosporidium parvum * immunomodulation * liposomes Subject RIV: EC - Immunology Impact factor: 1.703, year: 2005

In silico identification of essential proteins in Corynebacterium pseudotuberculosis based on protein

DEFF Research Database (Denmark)

Folador, Edson Luiz; de Carvalho, Paulo Vinícius Sanches Daltro; Silva, Wanderson Marques

2016-01-01

BACKGROUND: Corynebacterium pseudotuberculosis (Cp) is a gram-positive bacterium that is classified into equi and ovis serovars. The serovar ovis is the etiological agent of caseous lymphadenitis, a chronic infection affecting sheep and goats, causing economic losses due to carcass condemnation...... of the potential Cp interactome and to identify potentially essential proteins serving as putative drug targets. On average, we predict 16,669 interactions for each of the nine strains (with 15,495 interactions shared among all strains). An in silico sanity check suggests that the potential networks were...... not formed by spurious interactions but have a strong biological bias. With the inferred Cp networks we identify 181 essential proteins, among which 41 are non-host homologous. CONCLUSIONS: The list of candidate interactions of the Cp strains lay the basis for developing novel hypotheses and designing...

CRISPR/Cas9-coupled recombineering for metabolic engineering of Corynebacterium glutamicum.

Science.gov (United States)

Cho, Jae Sung; Choi, Kyeong Rok; Prabowo, Cindy Pricilia Surya; Shin, Jae Ho; Yang, Dongsoo; Jang, Jaedong; Lee, Sang Yup

2017-07-01

Genome engineering of Corynebacterium glutamicum, an important industrial microorganism for amino acids production, currently relies on random mutagenesis and inefficient double crossover events. Here we report a rapid genome engineering strategy to scarlessly knock out one or more genes in C. glutamicum in sequential and iterative manner. Recombinase RecT is used to incorporate synthetic single-stranded oligodeoxyribonucleotides into the genome and CRISPR/Cas9 to counter-select negative mutants. We completed the system by engineering the respective plasmids harboring CRISPR/Cas9 and RecT for efficient curing such that multiple gene targets can be done iteratively and final strains will be free of plasmids. To demonstrate the system, seven different mutants were constructed within two weeks to study the combinatorial deletion effects of three different genes on the production of γ-aminobutyric acid, an industrially relevant chemical of much interest. This genome engineering strategy will expedite metabolic engineering of C. glutamicum. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Comparative efficacy of curcumin and paromomycin against Cryptosporidium parvum infection in a BALB/c model.

Science.gov (United States)

Asadpour, Mohammad; Namazi, Fatemeh; Razavi, Seyed Mostafa; Nazifi, Saeed

2018-01-30

Cryptosporidium is a ubiquitous protozoan parasite causing gastrointestinal disorder in various hosts worldwide. The disease is self-limiting in the immunocompetent but life-threatening in immunodeficient individuals. Investigations to find an effective drug for the complete elimination of the Cryptosporidium infection are ongoing and urgently needed. The current study was undertaken to examine the anti-cryptosporidial efficacy of curcumin in experimentally infected mice compared with that of paromomycin. Oocysts were isolated from a pre-weaned dairy calf and identified as Cryptosporidium parvum using a nested- polymerase chain reaction (PCR) on Small subunit ribosomal ribonucleic acid (SSU rRNA) gene and sequencing analysis. One hundred and ten female BALB/c mice were divided into five groups. Group 1 was infected and treated with curcumin; Group 2 infected and treated with paromomycin; Group 3 infected without treatment; Group 4 included uninfected mice treated with curcumin, and Group 5 included uninfected mice treated with distilled water for 11 successive days, starting on the first day of oocyst shedding. The oocyst shedding was recorded daily. At days 0, 3, 7, and 11 of post treatments, five mice from each group were killed humanly; jejunum and ileum tissue samples were processed for histopathological evaluation and counting of oocyst on villi, simultaneously. Furthermore, total antioxidant capacity (TAC) and malondialdehyde (MDA) concentrations in affected tissues were also measured in different groups. By treatments, tissue lesions and the number of oocyst on villi of both jejunum and ileum were decreased with a time-dependent manner. In comparison with Group 3, oocyst shedding was stopped at the end of treatment period in both groups 1 and 2 without recurrence at 10days after drug withdrawal. Also, TAC was increased and the MDA concentrations were decreased in Group 1. Moreover, paromomycin showed acceptable treatment outcomes during experiment and its

Genes expressed in grapevine leaves reveal latent wood infection by the fungal pathogen Neofusicoccum parvum.

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Stefan Czemmel

Full Text Available Some pathogenic species of the Botryosphaeriaceae have a latent phase, colonizing woody tissues while perennial hosts show no apparent symptoms until conditions for disease development become favorable. Detection of these pathogens is often limited to the later pathogenic phase. The latent phase is poorly characterized, despite the need for non-destructive detection tools and effective quarantine strategies, which would benefit from identification of host-based markers in leaves. Neofusicoccum parvum infects the wood of grapevines and other horticultural crops, killing the fruit-bearing shoots. We used light microscopy and high-resolution computed tomography (HRCT to examine the spatio-temporal relationship between pathogen colonization and anatomical changes in stem sections. To identify differentially-expressed grape genes, leaves from inoculated and non-inoculated plants were examined using RNA-Seq. The latent phase occurred between 0 and 1.5 months post-inoculation (MPI, during which time the pathogen did not spread significantly beyond the inoculation site nor were there differences in lesion lengths between inoculated and non-inoculated plants. The pathogenic phase occurred between 1.5 and 2 MPI, when recovery beyond the inoculation site increased and lesion lengths of inoculated plants tripled. By 2 MPI, inoculated plants also had decreased starch content in xylem fibers and rays, and increased levels of gel-occluded xylem vessels, the latter of which HRCT revealed at a higher frequency than microscopy. RNA-Seq and screening of 21 grape expression datasets identified 20 candidate genes that were transcriptionally-activated by infection during the latent phase, and confirmed that the four best candidates (galactinol synthase, abscisic acid-induced wheat plasma membrane polypeptide-19 ortholog, embryonic cell protein 63, BURP domain-containing protein were not affected by a range of common foliar and wood pathogens or abiotic stresses

In Silico Genome-Scale Reconstruction and Validation of the Corynebacterium glutamicum Metabolic Network

DEFF Research Database (Denmark)

Kjeldsen, Kjeld Raunkjær; Nielsen, J.

2009-01-01

A genome-scale metabolic model of the Gram-positive bacteria Corynebacterium glutamicum ATCC 13032 was constructed comprising 446 reactions and 411 metabolite, based on the annotated genome and available biochemical information. The network was analyzed using constraint based methods. The model...... was extensively validated against published flux data, and flux distribution values were found to correlate well between simulations and experiments. The split pathway of the lysine synthesis pathway of C. glutamicum was investigated, and it was found that the direct dehydrogenase variant gave a higher lysine...... yield than the alternative succinyl pathway at high lysine production rates. The NADPH demand of the network was not found to be critical for lysine production until lysine yields exceeded 55% (mmol lysine (mmol glucose)(-1)). The model was validated during growth on the organic acids acetate...

Rapid Quantification of the Toxic Alga Prymnesium parvum in Natural Samples by Use of a Specific Monoclonal Antibody and Solid-Phase Cytometry

DEFF Research Database (Denmark)

West, N. J.; Bacchieri, R.; Hansen, Gert

2006-01-01

The increasing incidence of harmful algal blooms around the world and their associated health and economic effects require the development of methods to rapidly and accurately detect and enumerate the target species. Here we describe use of a solid-phase cytometer to detect and enumerate the toxi......-phase cytometer can be used to rapidly enumerate natural P. parvum cells and that it could be used to detect other toxic algae, with an appropriate antibody or DNA probe....

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa).

Science.gov (United States)

Benamrouz, S; Conseil, V; Creusy, C; Calderon, E; Dei-Cas, E; Certad, G

2012-05-01

The International Agency for Research on Cancer (IARC) identifies ten infectious agents (viruses, bacteria, parasites) able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites) with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa

Directory of Open Access Journals (Sweden)

Benamrouz S.

2012-05-01

Full Text Available The International Agency for Research on Cancer (IARC identifies ten infectious agents (viruses, bacteria, parasites able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

T cell cytokine responses to stimulation with Ureaplasma parvum in pregnancy.

Science.gov (United States)

Friedland, Yael D; Lee-Pullen, Tracey F; Nathan, Elizabeth A; Watts, Rory; Keelan, Jeffrey A; Payne, Matthew S; Ireland, Demelza J

2016-08-01

Ureaplasma spp. are a common vaginal microorganism causally linked to inflammation-driven preterm birth (PTB). The nature of the immune response to Ureaplasma spp. may influence PTB risk. This study sought to define maternal T cell cytokine responses to in vitro stimulation with Ureaplasma parvum serovar 3 (UpSV3) in vaginally colonised (UP+) and non-colonised (UP-) pregnant women. Whole blood flow cytometry demonstrated an increase (p=0.027) in the baseline frequency of IFNγ-positive CD3(+)CD4(-)(CD8(+)) T cells in UP+ women. UpSV3 stimulation resulted in a significant and specific increase (p=0.001) in the frequency of IFNγ-positive CD3(+)CD4(-)(CD8(+)) T cells, regardless of vaginal colonisation status. UpSV3 stimulation also increased the frequency of IFNγ-positive CD3(+)CD4(+) T cells, particularly in the UP+ group (p=0.003). This is the first published study to examine T cell responses to Ureaplasma spp. Future appropriately-powered studies are needed to assess whether insufficient priming or a loss of tolerance to Ureaplasma spp. is occurring in UP+ women at risk of PTB. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Identification and characterization of smallest pore-forming protein in the cell wall of pathogenic Corynebacterium urealyticum DSM 7109.

Science.gov (United States)

Abdali, Narges; Younas, Farhan; Mafakheri, Samaneh; Pothula, Karunakar R; Kleinekathöfer, Ulrich; Tauch, Andreas; Benz, Roland

2018-05-09

Corynebacterium urealyticum, a pathogenic, multidrug resistant member of the mycolata, is known as causative agent of urinary tract infections although it is a bacterium of the skin flora. This pathogenic bacterium shares with the mycolata the property of having an unusual cell envelope composition and architecture, typical for the genus Corynebacterium. The cell wall of members of the mycolata contains channel-forming proteins for the uptake of solutes. In this study, we provide novel information on the identification and characterization of a pore-forming protein in the cell wall of C. urealyticum DSM 7109. Detergent extracts of whole C. urealyticum cultures formed in lipid bilayer membranes slightly cation-selective pores with a single-channel conductance of 1.75 nS in 1 M KCl. Experiments with different salts and non-electrolytes suggested that the cell wall pore of C. urealyticum is wide and water-filled and has a diameter of about 1.8 nm. Molecular modelling and dynamics has been performed to obtain a model of the pore. For the search of the gene coding for the cell wall pore of C. urealyticum we looked in the known genome of C. urealyticum for a similar chromosomal localization of the porin gene to known porH and porA genes of other Corynebacterium strains. Three genes are located between the genes coding for GroEL2 and polyphosphate kinase (PKK2). Two of the genes (cur_1714 and cur_1715) were expressed in different constructs in C. glutamicum ΔporAΔporH and in porin-deficient BL21 DE3 Omp8 E. coli strains. The results suggested that the gene cur_1714 codes alone for the cell wall channel. The cell wall porin of C. urealyticum termed PorACur was purified to homogeneity using different biochemical methods and had an apparent molecular mass of about 4 kDa on tricine-containing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Biophysical characterization of the purified protein (PorACur) suggested indeed that cur_1714 is the gene

Rickettsia rickettsii isolation from naturally infected Amblyomma parvum ticks by centrifugation in a 24-well culture plate technique

Directory of Open Access Journals (Sweden)

K. Dzul-Rosado

2013-09-01

Full Text Available Rocky Mountain spotted fever is an acute illness caused by Rickettsia rickettsii (R. rickettsii and is transmitted by the bite of ticks of the genera Dermacentor, Amblyomma and Rhipicephalus. The illness results in a high mortality rate and may be easily confused with other febrile syndromes. In Yucatan State, Mexico, childhood cases with a high mortality have been reported. In this work we report the isolation of a Mexican R. rickettsii strain from a tick egg mass using an alternative method for Rickettsia isolation with 24-well plates. We also identified a potential vector of R. rickettsii in the southeast of Mexico, which is Amblyomma parvum.

Synergic activation of toll-like receptor (TLR) 2/6 and 9 in response to Ureaplasma parvum & urealyticum in human amniotic epithelial cells.

Science.gov (United States)

Triantafilou, Martha; De Glanville, Benjamin; Aboklaish, Ali F; Spiller, O Brad; Kotecha, Sailesh; Triantafilou, Kathy

2013-01-01

Ureaplasma species are the most frequently isolated microorganisms inside the amniotic cavity and have been associated with spontaneous abortion, chorioamnionitis, premature rupture of the membranes (PROM), preterm labour (PL) pneumonia in neonates and bronchopulmonary dysplasia in neonates. The mechanisms by which Ureaplasmas cause such diseases remain unclear, but it is believed that inappropriate induction of inflammatory responses is involved, triggered by the innate immune system. As part of its mechanism of activation, the innate immune system employs germ-lined encoded receptors, called pattern recognition receptors (PRRs) in order to "sense" pathogens. One such family of PRRs are the Toll like receptor family (TLR). In the current study we aimed to elucidate the role of TLRs in Ureaplasma-induced inflammation in human amniotic epithelial cells. Using silencing, as well as human embryonic kidney (HEK) transfected cell lines, we demonstrate that TLR2, TLR6 and TLR9 are involved in the inflammatory responses against Ureaplasma parvum and urealyticum serovars. Ureaplasma lipoproteins, such as Multiple Banded antigen (MBA), trigger responses via TLR2/TLR6, whereas the whole bacterium is required for TLR9 activation. No major differences were observed between the different serovars. Cell activation by Ureaplasma parvum and urealyticum seem to require lipid raft function and formation of heterotypic receptor complexes comprising of TLR2 and TLR6 on the cell surface and TLR9 intracellularly.

Synergic activation of toll-like receptor (TLR 2/6 and 9 in response to Ureaplasma parvum & urealyticum in human amniotic epithelial cells.

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Martha Triantafilou

Full Text Available Ureaplasma species are the most frequently isolated microorganisms inside the amniotic cavity and have been associated with spontaneous abortion, chorioamnionitis, premature rupture of the membranes (PROM, preterm labour (PL pneumonia in neonates and bronchopulmonary dysplasia in neonates. The mechanisms by which Ureaplasmas cause such diseases remain unclear, but it is believed that inappropriate induction of inflammatory responses is involved, triggered by the innate immune system. As part of its mechanism of activation, the innate immune system employs germ-lined encoded receptors, called pattern recognition receptors (PRRs in order to "sense" pathogens. One such family of PRRs are the Toll like receptor family (TLR. In the current study we aimed to elucidate the role of TLRs in Ureaplasma-induced inflammation in human amniotic epithelial cells. Using silencing, as well as human embryonic kidney (HEK transfected cell lines, we demonstrate that TLR2, TLR6 and TLR9 are involved in the inflammatory responses against Ureaplasma parvum and urealyticum serovars. Ureaplasma lipoproteins, such as Multiple Banded antigen (MBA, trigger responses via TLR2/TLR6, whereas the whole bacterium is required for TLR9 activation. No major differences were observed between the different serovars. Cell activation by Ureaplasma parvum and urealyticum seem to require lipid raft function and formation of heterotypic receptor complexes comprising of TLR2 and TLR6 on the cell surface and TLR9 intracellularly.

Systems-wide metabolic pathway engineering in Corynebacterium glutamicum for bio-based production of diaminopentane.

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Kind, Stefanie; Jeong, Weol Kyu; Schröder, Hartwig; Wittmann, Christoph

2010-07-01

In the present work the Gram-positive bacterium Corynebacterium glutamicum was engineered into an efficient, tailor-made production strain for diaminopentane (cadaverine), a highly attractive building block for bio-based polyamides. The engineering comprised expression of lysine decarboxylase (ldcC) from Escherichia coli, catalyzing the conversion of lysine into diaminopentane, and systems-wide metabolic engineering of central supporting pathways. Substantially re-designing the metabolism yielded superior strains with desirable properties such as (i) the release from unwanted feedback regulation at the level of aspartokinase and pyruvate carboxylase by introducing the point mutations lysC311 and pycA458, (ii) an optimized supply of the key precursor oxaloacetate by amplifying the anaplerotic enzyme, pyruvate carboxylase, and deleting phosphoenolpyruvate carboxykinase which otherwise removes oxaloacetate, (iii) enhanced biosynthetic flux via combined amplification of aspartokinase, dihydrodipicolinate reductase, diaminopimelate dehydrogenase and diaminopimelate decarboxylase, and (iv) attenuated flux into the threonine pathway competing with production by the leaky mutation hom59 in the homoserine dehydrogenase gene. Lysine decarboxylase proved to be a bottleneck for efficient production, since its in vitro activity and in vivo flux were closely correlated. To achieve an optimal strain having only stable genomic modifications, the combination of the strong constitutive C. glutamicum tuf promoter and optimized codon usage allowed efficient genome-based ldcC expression and resulted in a high diaminopentane yield of 200 mmol mol(-1). By supplementing the medium with 1 mgL(-1) pyridoxal, the cofactor of lysine decarboxylase, the yield was increased to 300 mmol mol(-1). In the production strain obtained, lysine secretion was almost completely abolished. Metabolic analysis, however, revealed substantial formation of an as yet unknown by-product. It was identified as an

Functional analysis of sequences adjacent to dapE of Corynebacterium glutamicum reveals the presence of aroP, which encodes the aromatic amino acid transporter.

Science.gov (United States)

Wehrmann, A; Morakkabati, S; Krämer, R; Sahm, H; Eggeling, L

1995-10-01

An initially nonclonable DNA locus close to a gene of L-lysine biosynthesis in Corynebacterium glutamicum was analyzed in detail. Its stepwise cloning and its functional identification by monitoring the amino acid uptakes of defined mutants, together with mechanistic studies, identified the corresponding structure as aroP, the general aromatic amino acid uptake system.

Identification and determination of the viability of Giardia lamblia cysts and Cryptosporidium parvum and Cryptosporidium hominis oocysts in human fecal and water supply samples by fluorescent in situ hybridization (FISH) and monoclonal antibodies.

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Lemos, Vanessa; Graczyk, Thaddeus K; Alves, Margarida; Lobo, Maria Luísa; Sousa, Maria C; Antunes, Francisco; Matos, Olga

2005-12-01

In the present study, fluorescent in situ hybridization (FISH) and monoclonal antibodies (MAbs) were evaluated for species-specific detection and viability determination of Giardia lamblia, Cryptosporidium parvum, and Cryptosporidium hominis in human fecal and water supply samples. A total of 50 fecal human samples positive for G. lamblia cysts, 38 positive for C. parvum, and 23 positive for C. hominis were studied. Also, 18 water supply samples positive for Giardia spp. and Cryptosporidium spp. by the United States Environmental Protection Agency (USEPA) Method 1623 were studied by FISH and fluorescein isothiocyanate (FITC)-conjugated MAbs. Eighteen percent of the fecal samples parasitologically positive for G. lamblia presented viable and nonviable cysts, and 5% of those positive for Cryptosporidium spp. presented viable and nonviable oocysts. Of the 18 water supply samples analyzed, 6 (33%) presented Giardia spp. viable and nonviable cysts and 2 (11%) presented viable and nonviable Cryptosporidium spp. oocysts. G. lamblia identification was confirmed by polymerase chain reaction (PCR) and sequencing of the beta-giardin gene in the fecal and water samples found positive by FISH and FITC-conjugated MAbs. C. parvum and Cryptosporidium muris were identified, by PCR and sequencing of the small subunit of ribosomal RNA gene, in seven and one water samples, respectively. Our results confirm that this technique enables simultaneous visualization, species-specific identification, and viability determination of the organisms present in human fecal and water supply samples.

ORF Alignment: ch_oct10_gene_aa_db [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ith 3x EFh domains [Cryptosporidium parvum] ... Length = 160 ... Query: 4 ... NESSGISEQEKLELVHAASFTRRDIIRIYSRFKALDTNQNGELDPHE...LFEMPEIADNPLV 63 ... NESSGISEQEKLELVHAASFTRRDIIRIYSRFKALDTNQNGELDPHELFEMPEIADNPLV ...Sbjct: 1 ... NESSGISEQEKLELVHAASFTRRDIIRIYSRFKALDTNQNGELDPHELFEMPEIADNPLV 60 ... Query

Molecular characterization of Cryptosporidium spp. in pre-weaned dairy calves in the Czech Republic: Absence of C. ryanae and management-associated distribution of C. andersoni, C. bovis and C. parvum subtypes

Czech Academy of Sciences Publication Activity Database

Kváč, Martin; Hromadová, N.; Květoňová, Dana; Rost, M.; Sak, Bohumil

2011-01-01

Roč. 177, 3/4 (2011), s. 378-382 ISSN 0304-4017 Institutional research plan: CEZ:AV0Z60220518 Keywords : Calves * Cryptosporidium andersoni * C. bovis * C. parvum * GP60 * SSU Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.579, year: 2011

Vaccination of adult and newborn mice of a resistant strain (C57BL/6J) against challenge with leukemias induced by Moloney murine leukemia virus

International Nuclear Information System (INIS)

Reif, A.E.

1985-01-01

Adult or newborn C57BL/6J mice were immunized with isogenic Moloney strain MuLV-induced leukemia cells irradiated with 10,000 rads or treated with low concentrations of formalin. Groups of immunized and control mice were challenged with a range of doses of viable leukemia cells, and tumor deaths were recorded for 90 days after challenge. Then, the doses of challenge cells which produced 50% tumor deaths were calculated for immunized and control mice. The logarithm of their ratio quantified the degree of protection provided by immunization. For adult C57BL/6J mice, a single immunization with MuLV-induced leukemia cells was not effective; either cells plus Bacillus Calmette-Guerin or Corynebacterium parvum, or else two immunizations with irradiated leukemia cells were needed to produce statistically significant increases in the values of the doses of challenge cells which produced 50% tumor deaths. Cross-protection was obtained by immunization with other isogenic MuLV-induced leukemias, but not by immunization with isogenic carcinogen-induced tumors or with an isogenic spontaneous leukemia. For newborn mice, a single injection of irradiated leukemia cells provided 1.3 to 1.5 logs of protection, and admixture of B. Calmette-Guerin or C. parvum increased this protection to 2.4 to 2.7 logs. Since irradiated and frozen-thawed MuLV-induced leukemia cells contained viable MuLV, leukemia cells treated with 0.5 or 1.0% formalin were tested as an alternative. A single injection of formalin-treated isogenic leukemia cells admixed with C. parvum provided between 1.7 and 2.8 logs of protection. These results demonstrate that a single vaccination of newborn animals against a highly antigenic virally induced leukemia produces strong protection against a subsequent challenge with viable leukemia cells

The two-component signal transduction system CopRS of Corynebacterium glutamicum is required for adaptation to copper-excess stress

OpenAIRE

Schelder, S.; Zaade, D.; Litsanov, B.; Bott, M.; Brocker, M.

2011-01-01

Copper is an essential cofactor for many enzymes but at high concentrations it is toxic for the cell. Copper ion concentrations ≥50 µM inhibited growth of Corynebacterium glutamicum. The transcriptional response to 20 µM Cu(2+) was studied using DNA microarrays and revealed 20 genes that showed a ≥ 3-fold increased mRNA level, including cg3281-cg3289. Several genes in this genomic region code for proteins presumably involved in the adaption to copper-induced stress, e. g. a multicopper oxidas...

Transcriptomic Changes in Response to Putrescine Production in Metabolically Engineered Corynebacterium glutamicum

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Zhen Li

2017-10-01

Full Text Available Putrescine is widely used in industrial production of bioplastics, pharmaceuticals, agrochemicals, and surfactants. Although engineered Corynebacterium glutamicum has been successfully used to produce high levels of putrescine, the overall cellular physiological and metabolic changes caused by overproduction of putrescine remains unclear. To reveal the transcriptional changes that occur in response to putrescine production in an engineered C. glutamicum strain, a comparative transcriptomic analysis was carried out. Overproduction of putrescine resulted in transcriptional downregulation of genes involved in glycolysis; the TCA cycle, pyruvate degradation, biosynthesis of some amino acids, oxidative phosphorylation; vitamin biosynthesis (thiamine and vitamin 6, metabolism of purine, pyrimidine and sulfur, and ATP-, NAD-, and NADPH-consuming enzymes. The transcriptional levels of genes involved in ornithine biosynthesis and NADPH-forming related enzymes were significantly upregulated in the putrescine producing C. glutamicum strain PUT-ALE. Comparative transcriptomic analysis provided some genetic modification strategies to further improve putrescine production. Repressing ATP- and NADPH-consuming enzyme coding gene expression via CRISPRi enhanced putrescine production.

Transcriptomic Changes in Response to Putrescine Production in Metabolically Engineered Corynebacterium glutamicum

Science.gov (United States)

Li, Zhen; Liu, Jian-Zhong

2017-01-01

Putrescine is widely used in industrial production of bioplastics, pharmaceuticals, agrochemicals, and surfactants. Although engineered Corynebacterium glutamicum has been successfully used to produce high levels of putrescine, the overall cellular physiological and metabolic changes caused by overproduction of putrescine remains unclear. To reveal the transcriptional changes that occur in response to putrescine production in an engineered C. glutamicum strain, a comparative transcriptomic analysis was carried out. Overproduction of putrescine resulted in transcriptional downregulation of genes involved in glycolysis; the TCA cycle, pyruvate degradation, biosynthesis of some amino acids, oxidative phosphorylation; vitamin biosynthesis (thiamine and vitamin 6), metabolism of purine, pyrimidine and sulfur, and ATP-, NAD-, and NADPH-consuming enzymes. The transcriptional levels of genes involved in ornithine biosynthesis and NADPH-forming related enzymes were significantly upregulated in the putrescine producing C. glutamicum strain PUT-ALE. Comparative transcriptomic analysis provided some genetic modification strategies to further improve putrescine production. Repressing ATP- and NADPH-consuming enzyme coding gene expression via CRISPRi enhanced putrescine production. PMID:29089930

Detoxification of furfural in Corynebacterium glutamicum under aerobic and anaerobic conditions.

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Tsuge, Yota; Hori, Yoshimi; Kudou, Motonori; Ishii, Jun; Hasunuma, Tomohisa; Kondo, Akihiko

2014-10-01

The toxic fermentation inhibitors in lignocellulosic hydrolysates raise serious problems for the microbial production of fuels and chemicals. Furfural is considered to be one of the most toxic compounds among these inhibitors. Here, we describe the detoxification of furfural in Corynebacterium glutamicum ATCC13032 under both aerobic and anaerobic conditions. Under aerobic culture conditions, furfuryl alcohol and 2-furoic acid were produced as detoxification products of furfural. The ratio of the products varied depending on the initial furfural concentration. Neither furfuryl alcohol nor 2-furoic acid showed any toxic effect on cell growth, and both compounds were determined to be the end products of furfural degradation. Interestingly, unlike under aerobic conditions, most of the furfural was converted to furfuryl alcohol under anaerobic conditions, without affecting the glucose consumption rate. Both the NADH/NAD(+) and NADPH/NADP(+) ratio decreased in the accordance with furfural concentration under both aerobic and anaerobic conditions. These results indicate the presence of a single or multiple endogenous enzymes with broad and high affinity for furfural and co-factors in C. glutamicum ATCC13032.

Brain and lung cryptococcoma and concurrent corynebacterium pseudotuberculosis infection in a goat: a case report

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MCR Luvizotto

2009-01-01

Full Text Available A four-year-old male goat with a history of neurological disorder was euthanized. It presented uncommon nodules in the brain and lungs associated with multiple abscesses, predominantly in the spleen and liver. Histological examination of brain and lung sections revealed yeast forms confirmed to be Cryptococcus gattii after a combination of isolation and polymerase chain reaction (PCR procedures. Moreover, Corynebacterium pseudotuberculosis infection was diagnosed by PCR of samples from the lung, spleen and liver. The present report highlights the rare concurrent infection of C. gatti and C. pseudotuberculosis in an adult goat from São Paulo state, Brazil, and indicates the necessity of surveillance in the treatment of goats with atypical pulmonary infections associated with neurological disorders.

Involvement of Cryptosporidium parvum Cdg7_FLc_1000 RNA in the Attenuation of Intestinal Epithelial Cell Migration via Trans-Suppression of Host Cell SMPD3.

Science.gov (United States)

Ming, Zhenping; Gong, Ai-Yu; Wang, Yang; Zhang, Xin-Tian; Li, Min; Mathy, Nicholas W; Strauss-Soukup, Juliane K; Chen, Xian-Ming

2017-12-27

Intestinal infection by Cryptosporidium parvum causes inhibition of epithelial turnover, but underlying mechanisms are unclear. Previous studies demonstrate that a panel of parasite RNA transcripts of low protein-coding potential are delivered into infected epithelial cells. Using in vitro and in vivo models of intestinal cryptosporidiosis, we report here that host delivery of parasite Cdg7_FLc_1000 RNA results in inhibition of epithelial cell migration through suppression of the gene encoding sphingomyelinase 3 (SMPD3). Delivery of Cdg7_FLc_1000 into infected cells promotes the histone methyltransferase G9a-mediated H3K9 methylation in the SMPD3 locus. The DNA-binding transcriptional repressor, PR domain zinc finger protein 1, is required for the assembly of Cdg7_FLc_1000 into the G9a complex and associated with the enrichment of H3K9 methylation at the gene locus. Pathologically, nuclear transfer of Cryptosporidium parvum Cdg7_FLc_1000 RNA is involved in the attenuation of intestinal epithelial cell migration via trans-suppression of host cell SMPD3. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Quinone-dependent D-lactate dehydrogenase Dld (Cg1027 is essential for growth of Corynebacterium glutamicum on D-lactate

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Oikawa Tadao

2010-12-01

Full Text Available Abstract Background Corynebacterium glutamicum is able to grow with lactate as sole or combined carbon and energy source. Quinone-dependent L-lactate dehydrogenase LldD is known to be essential for utilization of L-lactate by C. glutamicum. D-lactate also serves as sole carbon source for C. glutamicum ATCC 13032. Results Here, the gene cg1027 was shown to encode the quinone-dependent D-lactate dehydrogenase (Dld by enzymatic analysis of the protein purified from recombinant E. coli. The absorption spectrum of purified Dld indicated the presence of FAD as bound cofactor. Inactivation of dld resulted in the loss of the ability to grow with D-lactate, which could be restored by plasmid-borne expression of dld. Heterologous expression of dld from C. glutamicum ATCC 13032 in C. efficiens enabled this species to grow with D-lactate as sole carbon source. Homologs of dld of C. glutamicum ATCC 13032 are not encoded in the sequenced genomes of other corynebacteria and mycobacteria. However, the dld locus of C. glutamicum ATCC 13032 shares 2367 bp of 2372 bp identical nucleotides with the dld locus of Propionibacterium freudenreichii subsp. shermanii, a bacterium used in Swiss-type cheese making. Both loci are flanked by insertion sequences of the same family suggesting a possible event of horizontal gene transfer. Conclusions Cg1067 encodes quinone-dependent D-lactate dehydrogenase Dld of Corynebacterium glutamicum. Dld is essential for growth with D-lactate as sole carbon source. The genomic region of dld likely has been acquired by horizontal gene transfer.

ORF Alignment: NC_003450 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_003450 gi|19553429 >1v4aA 22 435 620 1034 4e-69 ... ref|YP_226470.1| GLUTAMATE-AMMONIA...mb|CAF20569.1| ... GLUTAMATE-AMMONIA-LIGASE ADENYLYLTRANSFERASE ... [Corynebacterium glutami

Crystallization and preliminary X-ray diffraction studies of FAD synthetase from Corynebacterium ammoniagenes

International Nuclear Information System (INIS)

Herguedas, Beatriz; Martínez-Júlvez, Marta; Frago, Susana; Medina, Milagros; Hermoso, Juan A.

2009-01-01

Native and selenomethionine-labelled FAD synthetase from C. ammoniagenes have been crystallized by the hanging-drop vapour-diffusion method. A MAD data set for SeMet-labelled FAD synthetase was collected to 2.42 Å resolution, while data sets were collected to 1.95 Å resolution for the native crystals. FAD synthetase from Corynebacterium ammoniagenes (CaFADS), a prokaryotic bifunctional enzyme that catalyses the phosphorylation of riboflavin as well as the adenylylation of FMN, has been crystallized using the hanging-drop vapour-diffusion method at 277 K. Diffraction-quality cubic crystals of native and selenomethionine-labelled (SeMet-CaFADS) protein belonged to the cubic space group P2 1 3, with unit-cell parameters a = b = c = 133.47 Å and a = b = c = 133.40 Å, respectively. Data sets for native and SeMet-containing crystals were collected to 1.95 and 2.42 Å resolution, respectively

The Druggable Pocketome of Corynebacterium diphtheriae: A New Approach for in silico Putative Druggable Targets

Science.gov (United States)

Hassan, Syed S.; Jamal, Syed B.; Radusky, Leandro G.; Tiwari, Sandeep; Ullah, Asad; Ali, Javed; Behramand; de Carvalho, Paulo V. S. D.; Shams, Rida; Khan, Sabir; Figueiredo, Henrique C. P.; Barh, Debmalya; Ghosh, Preetam; Silva, Artur; Baumbach, Jan; Röttger, Richard; Turjanski, Adrián G.; Azevedo, Vasco A. C.

2018-01-01

Diphtheria is an acute and highly infectious disease, previously regarded as endemic in nature but vaccine-preventable, is caused by Corynebacterium diphtheriae (Cd). In this work, we used an in silico approach along the 13 complete genome sequences of C. diphtheriae followed by a computational assessment of structural information of the binding sites to characterize the “pocketome druggability.” To this end, we first computed the “modelome” (3D structures of a complete genome) of a randomly selected reference strain Cd NCTC13129; that had 13,763 open reading frames (ORFs) and resulted in 1,253 (∼9%) structure models. The amino acid sequences of these modeled structures were compared with the remaining 12 genomes and consequently, 438 conserved protein sequences were obtained. The RCSB-PDB database was consulted to check the template structures for these conserved proteins and as a result, 401 adequate 3D models were obtained. We subsequently predicted the protein pockets for the obtained set of models and kept only the conserved pockets that had highly druggable (HD) values (137 across all strains). Later, an off-target host homology analyses was performed considering the human proteome using NCBI database. Furthermore, the gene essentiality analysis was carried out that gave a final set of 10-conserved targets possessing highly druggable protein pockets. To check the target identification robustness of the pipeline used in this work, we crosschecked the final target list with another in-house target identification approach for C. diphtheriae thereby obtaining three common targets, these were; hisE-phosphoribosyl-ATP pyrophosphatase, glpX-fructose 1,6-bisphosphatase II, and rpsH-30S ribosomal protein S8. Our predicted results suggest that the in silico approach used could potentially aid in experimental polypharmacological target determination in C. diphtheriae and other pathogens, thereby, might complement the existing and new drug-discovery pipelines

ORF Alignment: NC_006361 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_006361 gi|54024866 >1jmvA 2 140 154 297 6e-16 ... ref|YP_227183.1| UNIVERSAL STRESS...icum ATCC 13032] ... emb|CAF20967.1| UNIVERSAL STRESS PROTEIN FAMILY ... [Corynebacterium glut

ORF Alignment: NC_003450 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_003450 gi|19554128 >1jmvA 2 140 154 297 6e-16 ... ref|YP_227183.1| UNIVERSAL STRESS...icum ATCC 13032] ... emb|CAF20967.1| UNIVERSAL STRESS PROTEIN FAMILY ... [Corynebacterium glut

Characterization and antimicrobial susceptibility of one antibiotic-sensitive and one multidrug-resistant Corynebacterium kroppenstedtii strain isolated from patients with granulomatous mastitis

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I. Fernández-Natal

2016-11-01

Full Text Available Human infections associated with Corynebacterium kroppenstedtii are rarely reported, and this organism is usually described as antibiotic sensitive. Almost all published cases of C. kroppenstedtii infections have been associated with breast pathology in women and have been described in New Zealand, France, Canada, India and Japan. Here we describe the microbiologic characteristics of two strains isolated from two women diagnosed of granulomatous mastitis in Spain. One C. kroppenstedtii isolate was antibiotic sensitive while the other was multidrug resistant. Biochemical identification was possible using a wide battery of methods including API Coryne V2.0, API Strep, API NH, API NE, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA gene amplification and sequencing. Antimicrobial susceptibility to 28 antibiotics as determined by Etest showed one isolate being sensitive to benzylpenicillin, ciprofloxacin, moxifloxacin, gentamicin, vancomycin, clindamycin, tetracycline, linezolid and rifampin. The second isolate showed resistance to ciprofloxacin, moxifloxacin, clindamycin, tetracycline and rifampin. The multidrug-resistant isolate contained the erm(X, tet(W, cmx, aphA1-IAB, strAB and sul1 resistance genes known from the R plasmid pJA144188 of Corynebacterium resistens. These genes were absent in the genome of the antibiotic-sensitive isolate. This report confirms the tropism of this microorganism for women's breasts and presents the first description of a multidrug-resistant C. kroppenstedtii strain.

Avaliação da resistência de 47 acessos de mangueira aos fungos Fusicoccum aesculis e Neofusicoccum parvum

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Diógenes da Cruz Batista

2012-09-01

Full Text Available A mangicultura praticada no Submédio do Vale do São Francisco é considerada um dos principais destaques no comércio externo do País. Dentre as diversas variedades cultivadas, a Tommy Atkins é a que representa a maior parte das exportações. Entretanto, a magnitude das perdas por podridões pós-colheita, causadas por fungos Botryosphaeriaceae, é sempre uma grande preocupação para exportadores e importadores da fruta. A busca por métodos de controle mais eficazes e limpos é uma tendência mundial. Nesse sentido, o objetivo deste trabalho foi avaliar a reação de frutos, de 47 acessos de mangueiras, quanto à resistência aos fungos Fusicoccum aesculis e Neofusicoccum parvum. As inoculações foram realizadas mediante deposição de disco do meio de cultura batata-dextrose-ágar (BDA, contendo estruturas do patógeno sobre duas posições opostas na região equatorial da manga, mantido, posteriormente, por 24 horas em câmara úmida. Foram realizadas medições das lesões até o sétimo dia, com uma régua milimetrada. Com os registros dos crescimentos das lesões, foram calculadas as taxas diárias de crescimento da lesão (TDCL's para cada acesso. As maiores TDCLs foram observadas nos acessos 'Roxa' e 'Lita', quando inoculados com F. aesculis, e nos acessos 'Roxa', 'Ruby', 'Papo de peru', 'CPAC 22/93', 'Pingo-de-ouro', 'Pêssego' e 'M13269', quando inoculados com N. parvum. Os acessos 'Nego-não-chupa', 'Manga-d'água', 'Juazeiro VI', 'Juazeiro VII' e 'Favo-de-mel' foram os que apresentaram, concomitantemente, as menores TDCLs para ambos os patógenos e diferenças significativas em relação aos demais acessos.

Comparison of transport and attachment behaviors of Cryptosporidium parvum oocysts and oocyst-sized microspheres being advected through three minerologically different granular porous media.

Science.gov (United States)

Mohanram, Arvind; Ray, Chittaranjan; Harvey, Ronald W; Metge, David W; Ryan, Joseph N; Chorover, Jon; Eberl, D D

2010-10-01

In order to gain more information about the fate of Cryptosporidium parvum oocysts in tropical volcanic soils, the transport and attachment behaviors of oocysts and oocyst-sized polystyrene microspheres were studied in the presence of two soils. These soils were chosen because of their differing chemical and physical properties, i.e., an organic-rich (43-46% by mass) volcanic ash-derived soil from the island of Hawaii, and a red, iron (22-29% by mass), aluminum (29-45% by mass), and clay-rich (68-76% by mass) volcanic soil from the island of Oahu. A third agricultural soil, an organic- (13% by mass) and quartz-rich (40% by mass) soil from Illinois, was included for reference. In 10-cm long flow-through columns, oocysts and microspheres advecting through the red volcanic soil were almost completely (98% and 99%) immobilized. The modest breakthrough resulted from preferential flow-path structure inadvertently created by soil-particle aggregation during the re-wetting process. Although a high (99%) removal of oocysts and microsphere within the volcanic ash soil occurred initially, further examination revealed that transport was merely retarded because of highly reversible interactions with grain surfaces. Judging from the slope of the substantive and protracted tail of the breakthrough curve for the 1.8-μm microspheres, almost all (>99%) predictably would be recovered within ∼4000 pore volumes. This suggests that once contaminated, the volcanic ash soil could serve as a reservoir for subsequent contamination of groundwater, at least for pathogens of similar size or smaller. Because of the highly reversible nature of organic colloid immobilization in this soil type, C. parvum could contaminate surface water should overland flow during heavy precipitation events pick up near-surface grains to which they are attached. Surprisingly, oocyst and microsphere attachment to the reference soil from Illinois appeared to be at least as sensitive to changes in pH as was

Ureaplasma urealyticum and Ureaplasma parvum in women of reproductive age.

Science.gov (United States)

Hunjak, Blaženka; Sabol, Ivan; Vojnović, Gordana; Fistonić, Ivan; Erceg, Andrea Babić; Peršić, Zdenka; Grce, Magdalena

2014-02-01

To determine the incidence of Ureaplasma urealyticum and Ureaplasma parvum (UP) in symptomatic and asymptomatic women of reproductive age and to estimate antibiotic susceptibility of ureaplasma isolates. This study included 424 ureaplasma positive women of 1,370 tested women who visited gynecological practices during 2010. Cervicovaginal or urethral swab specimens from each patient were obtained for cultivation and molecular typing by RT-PCR. Ureaplasma spp. was identified by cultivation in 424 (34.4 %) cases, of which 79.0 % were from women with symptoms and 21.0 % from women without symptoms. Among ureaplasma positive women, 121 (28.5 %) were pregnant. Genotyping was successful in 244 strains, and the majority of samples were identified as UP (92.6 %). Among genotyped isolates, there were 79.5 % from symptomatic and 20.5 % from asymptomatic women; 29.9 % from pregnant and 70.1 % from non-pregnant women. There was no difference in the incidence of ureaplasma type regarding symptoms. Antibiotic susceptibility of 424 ureaplasma isolates identified by cultivation showed that all strains were susceptible to doxycycline, josamycin, erythromycin, tetracycline, clarithromycin and pristinamycin, but there was lower susceptibility to quinolone antibiotics, i.e., 42.9 and 24.5 % isolates were susceptible to ofloxacin and ciprofloxacin, respectively. This study shows that UP was the most frequent isolated ureaplasma species (92.6 %). Regarding antibiotic susceptibility, quinolones are not the best choice for the treatment of ureaplasma infections, while macrolides and tetracyclines are still effective.

Expression, crystallization and preliminary crystallographic study of GluB from Corynebacterium glutamicum

International Nuclear Information System (INIS)

Liu, Qingbo; Li, Defeng; Hu, Yonglin; Wang, Da-Cheng

2013-01-01

GluB, a substrate-binding protein from C. glutamicum, was expressed, purified and crystallized, followed by X-ray diffraction data collection and preliminary crystallographic analysis. GluB is a substrate-binding protein (SBP) which participates in the uptake of glutamic acid in Corynebacterium glutamicum, a Gram-positive bacterium. It is part of an ATP-binding cassette (ABC) transporter system. Together with the transmembrane proteins GluC and GluD and the cytoplasmic protein GluA, which couples the hydrolysis of ATP to the translocation of glutamate, they form a highly active glutamate-uptake system. As part of efforts to study the amino-acid metabolism, especially the metabolism of glutamic acid by C. glutamicum, a bacterium that is widely used in the industrial production of glutamic acid, the GluB protein was expressed, purified and crystallized, an X-ray diffraction data set was collected to a resolution of 1.9 Å and preliminary crystallographic analysis was performed. The crystal belonged to space group P3 1 21 or P3 2 21, with unit-cell parameters a = b = 82.50, c = 72.69 Å

FudC, a protein primarily responsible for furfural detoxification in Corynebacterium glutamicum.

Science.gov (United States)

Tsuge, Yota; Kudou, Motonori; Kawaguchi, Hideo; Ishii, Jun; Hasunuma, Tomohisa; Kondo, Akihiko

2016-03-01

Lignocellulosic hydrolysates contain compounds that inhibit microbial growth and fermentation, thereby decreasing the productivity of biofuel and biochemical production. In particular, the heterocyclic aldehyde furfural is one of the most toxic compounds found in these hydrolysates. We previously demonstrated that Corynebacterium glutamicum converts furfural into the less toxic compounds furfuryl alcohol and 2-furoic acid. To date, however, the genes involved in these oxidation and reduction reactions have not been identified in the C. glutamicum genome. Here, we show that Cgl0331 (designated FudC) is mainly responsible for the reduction of furfural into furfuryl alcohol in C. glutamicum. Deletion of the gene encoding FudC markedly diminished the in vivo reduction of furfural to furfuryl alcohol. Purified His-tagged FudC protein from Escherichia coli was also shown to convert furfural into furfuryl alcohol in an in vitro reaction utilizing NADPH, but not NADH, as a cofactor. Kinetic measurements demonstrated that FudC has a high affinity for furfural but has a narrow substrate range for other aldehydes compared to the protein responsible for furfural reduction in E. coli.

Metabolic engineering of Corynebacterium glutamicum for fermentative production of chemicals in biorefinery.

Science.gov (United States)

Baritugo, Kei-Anne; Kim, Hee Taek; David, Yokimiko; Choi, Jong-Il; Hong, Soon Ho; Jeong, Ki Jun; Choi, Jong Hyun; Joo, Jeong Chan; Park, Si Jae

2018-05-01

Bio-based production of industrially important chemicals provides an eco-friendly alternative to current petrochemical-based processes. Because of the limited supply of fossil fuel reserves, various technologies utilizing microbial host strains for the sustainable production of platform chemicals from renewable biomass have been developed. Corynebacterium glutamicum is a non-pathogenic industrial microbial species traditionally used for L-glutamate and L-lysine production. It is a promising species for industrial production of bio-based chemicals because of its flexible metabolism that allows the utilization of a broad spectrum of carbon sources and the production of various amino acids. Classical breeding, systems, synthetic biology, and metabolic engineering approaches have been used to improve its applications, ranging from traditional amino-acid production to modern biorefinery systems for production of value-added platform chemicals. This review describes recent advances in the development of genetic engineering tools and techniques for the establishment and optimization of metabolic pathways for bio-based production of major C2-C6 platform chemicals using recombinant C. glutamicum.

Effects of radiation and other influences on chemical lymphomagenesis

Energy Technology Data Exchange (ETDEWEB)

Seidel, H.J.

1987-06-01

Methylnitrosourea (MNU) or butylnitrosourea (BNU) was used to induce T cell lymphomas (thymomas) in BDF/sub 1/ mice. In addition to the chemical, X-rays in various dose schedules were applied. An effect of the irradiation (shortening of the latency period) was seen with 12 x 0.25 Gy in protocols with a prolonged median induction time in the controls as a result of a dose reduction of the chemical (median induction time 27-36 weeks instead of 16-18 weeks under optimal conditions using 50 mg kg/sup -1/ of MNU). Preirradiation 2-5 weeks before 40 mg kg/sup -1/ of MNU resulted in enhanced leukaemogenesis. Also, mice with regenerating lympho-haemopoiesis after lethal irradiation and bone marrow transplantation were more sensitive to the effect of both chemicals than were the controls. Treatment with anti-thy 1.2 and with corynebacterium parvum during the latency period had no influence.

An unexpected phosphate binding site in Glyceraldehyde 3-Phosphate Dehydrogenase: Crystal structures of apo, holo and ternary complex of Cryptosporidium parvum enzyme

Energy Technology Data Exchange (ETDEWEB)

Cook, William J; Senkovich, Olga; Chattopadhyay, Debasish; (UAB)

2009-06-08

The structure, function and reaction mechanism of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) have been extensively studied. Based on these studies, three anion binding sites have been identified, one 'Ps' site (for binding the C-3 phosphate of the substrate) and two sites, 'Pi' and 'new Pi', for inorganic phosphate. According to the original flip-flop model, the substrate phosphate group switches from the 'Pi' to the 'Ps' site during the multistep reaction. In light of the discovery of the 'new Pi' site, a modified flip-flop mechanism, in which the C-3 phosphate of the substrate binds to the 'new Pi' site and flips to the 'Ps' site before the hydride transfer, was proposed. An alternative model based on a number of structures of B. stearothermophilus GAPDH ternary complexes (non-covalent and thioacyl intermediate) proposes that in the ternary Michaelis complex the C-3 phosphate binds to the 'Ps' site and flips from the 'Ps' to the 'new Pi' site during or after the redox step. We determined the crystal structure of Cryptosporidium parvum GAPDH in the apo and holo (enzyme + NAD) state and the structure of the ternary enzyme-cofactor-substrate complex using an active site mutant enzyme. The C. parvum GAPDH complex was prepared by pre-incubating the enzyme with substrate and cofactor, thereby allowing free movement of the protein structure and substrate molecules during their initial encounter. Sulfate and phosphate ions were excluded from purification and crystallization steps. The quality of the electron density map at 2{angstrom} resolution allowed unambiguous positioning of the substrate. In three subunits of the homotetramer the C-3 phosphate group of the non-covalently bound substrate is in the 'new Pi' site. A concomitant movement of the phosphate binding loop is observed in these three subunits. In the fourth subunit the C-3 phosphate

An unexpected phosphate binding site in Glyceraldehyde 3-Phosphate Dehydrogenase: Crystal structures of apo, holo and ternary complex of Cryptosporidium parvum enzyme

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Chattopadhyay Debasish

2009-02-01

Full Text Available Abstract Background The structure, function and reaction mechanism of glyceraldehyde 3-phosphate dehydrogenase (GAPDH have been extensively studied. Based on these studies, three anion binding sites have been identified, one 'Ps' site (for binding the C-3 phosphate of the substrate and two sites, 'Pi' and 'new Pi', for inorganic phosphate. According to the original flip-flop model, the substrate phosphate group switches from the 'Pi' to the 'Ps' site during the multistep reaction. In light of the discovery of the 'new Pi' site, a modified flip-flop mechanism, in which the C-3 phosphate of the substrate binds to the 'new Pi' site and flips to the 'Ps' site before the hydride transfer, was proposed. An alternative model based on a number of structures of B. stearothermophilus GAPDH ternary complexes (non-covalent and thioacyl intermediate proposes that in the ternary Michaelis complex the C-3 phosphate binds to the 'Ps' site and flips from the 'Ps' to the 'new Pi' site during or after the redox step. Results We determined the crystal structure of Cryptosporidium parvum GAPDH in the apo and holo (enzyme + NAD state and the structure of the ternary enzyme-cofactor-substrate complex using an active site mutant enzyme. The C. parvum GAPDH complex was prepared by pre-incubating the enzyme with substrate and cofactor, thereby allowing free movement of the protein structure and substrate molecules during their initial encounter. Sulfate and phosphate ions were excluded from purification and crystallization steps. The quality of the electron density map at 2Å resolution allowed unambiguous positioning of the substrate. In three subunits of the homotetramer the C-3 phosphate group of the non-covalently bound substrate is in the 'new Pi' site. A concomitant movement of the phosphate binding loop is observed in these three subunits. In the fourth subunit the C-3 phosphate occupies an unexpected site not seen before and the phosphate binding loop remains in

Transcriptional regulation of the operon encoding stress-responsive ECF sigma factor SigH and its anti-sigma factor RshA, and control of its regulatory network in Corynebacterium glutamicum

Czech Academy of Sciences Publication Activity Database

Busche, T.; Šilar, Radoslav; Pičmanová, Martina; Pátek, Miroslav; Kalinowski, J.

2012-01-01

Roč. 13, č. 445 (2012), s. 445-464 ISSN 1471-2164 R&D Projects: GA ČR GC204/09/J015 Institutional research plan: CEZ:AV0Z50200510 Keywords : Corynebacterium glutamicum * ECF sigma factor * Anti-sigma factor Subject RIV: EE - Microbiology, Virology Impact factor: 4.397, year: 2012

ORF Alignment: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_002162 gi|13358092 >6mhtA 61 323 7 298 3e-31 ... ref|NP_078366.1| cytosine-specifi...ic ... methyltransferase [Ureaplasma parvum serovar 3 str. ATCC ... 700970] pir||D82880 cytosi...ne-specific methyltransferase ... UU528 [imported] - Ureaplasma urealyticu...FGMKKGSGTRSGLLWEIERILFDLQKLNQ 60 ... Query: 127 LNYDGLIDSNGNILDLEAPIFDGKQKQLKDVLKTNY...KIEKYYQEAYLAQPNRTFSRIKYV 186 ... LNYDGLIDSNGNILDLEAPIFDGKQKQLKDVLKTNYKIEKYYQEAYLAQPNRTFSRIKYV Sbjct: 121 LNYDGLIDSNGNILDLEAP

Genetic variability of genital mycoplasmas and its clinical value

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K. I. Plakhova

2015-01-01

Full Text Available The article presents data on genetic variability of genital mycoplasmas. The author presents the results of genetic variability studies for M. hominis, gene vaa, U. parvum, gene mba, and M. genitalium, gene mg192, sampled from women with different clinical manifestations of inflammatory diseases of the urogenital system. Based on the molecular typing results for 138 samples of genital mycoplasmas, the author revealed a relationship between clinical manifestations of inflammatory diseases of the urogenital system caused by U. parvum and different U. parvum serovars as well as different genetic variations of M. hominis.Infection with 6 U. parvum serovar results in the development of inflammatory diseases of the urogenital tract accompanied by subjective manifestations (р < 0.05. Genetic variant II of М. hominis was revealed more often in patients with clinical manifestations of inflammatory diseases while variant I was revealed more often in patients infected with М. hominis without any signs of inflammation (р < 0.05. Genetic variants of M. genitalium were determined; no significant differences in terms of their prevalence in the examined patients were revealed.

Metabolic Engineering of Corynebacterium glutamicum for Methanol Metabolism

Science.gov (United States)

Witthoff, Sabrina; Schmitz, Katja; Niedenführ, Sebastian; Nöh, Katharina; Noack, Stephan

2015-01-01

Methanol is already an important carbon feedstock in the chemical industry, but it has found only limited application in biotechnological production processes. This can be mostly attributed to the inability of most microbial platform organisms to utilize methanol as a carbon and energy source. With the aim to turn methanol into a suitable feedstock for microbial production processes, we engineered the industrially important but nonmethylotrophic bacterium Corynebacterium glutamicum toward the utilization of methanol as an auxiliary carbon source in a sugar-based medium. Initial oxidation of methanol to formaldehyde was achieved by heterologous expression of a methanol dehydrogenase from Bacillus methanolicus, whereas assimilation of formaldehyde was realized by implementing the two key enzymes of the ribulose monophosphate pathway of Bacillus subtilis: 3-hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase. The recombinant C. glutamicum strain showed an average methanol consumption rate of 1.7 ± 0.3 mM/h (mean ± standard deviation) in a glucose-methanol medium, and the culture grew to a higher cell density than in medium without methanol. In addition, [13C]methanol-labeling experiments revealed labeling fractions of 3 to 10% in the m + 1 mass isotopomers of various intracellular metabolites. In the background of a C. glutamicum Δald ΔadhE mutant being strongly impaired in its ability to oxidize formaldehyde to CO2, the m + 1 labeling of these intermediates was increased (8 to 25%), pointing toward higher formaldehyde assimilation capabilities of this strain. The engineered C. glutamicum strains represent a promising starting point for the development of sugar-based biotechnological production processes using methanol as an auxiliary substrate. PMID:25595770

ORF Alignment: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ... antitermination factor [Ureaplasma parvum serovar 3 str. ... ATCC 700970] pir||A82874 tran...scription antitermination ... factor UU581 [imported] - Ureaplasma urealyt...icum ... Length = 137 ... Query: 24 ... HQWYIVTVVSGNEQKVIENIKDKLNGYGYGDKLSDLXXXXXXXXXXXXYEPSEAPRSMKN 83 ... ... ... HQWYIVTVVSGNEQKVIENIKDKLNGYGYGDKLSDL ... YEPSEAPRSMKN Sbjct: 1 ... HQWYIVTVVSGNEQKVIENIKDKLNGYG... NC_002162 gi|13358146 >1nz8A 2 112 24 160 9e-13 ... ref|NP_078420.1| transcription an

ORF Alignment: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available [imported] - ... Ureaplasma urealyticum ... Length = 313 ... Query: 8... NC_002162 gi|13357852 >1esc0 2 302 87 399 2e-29 ... ref|NP_078126.1| hypothetical protein UU292 [Ureap...lasma parvum serovar 3 str. ATCC ... 700970] gb|AAF30701.1| conserved hypothetical ... [Ureap...7 ... KINYLAIGDSITAGFNSELGWEAPGRYDPITNKISGLSFPSFIAQYINKVEPNRLASYEN 146 ... KINYLAIGDSITAGFNSELGWEAPGRYDP...ITNKISGLSFPSFIAQYINKVEPNRLASYEN Sbjct: 1 ... KINYLAIGDSITAGFNSELGWEAPGRYDPITNKISGLSFPSFIAQYINKVEPNRLASYEN 60 ...

ORF Alignment: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_002162 gi|13358063 >1t71A 5 267 1 262 2e-78 ... ref|NP_078337.1| hypothetical protein UU500 [Ureap...lasma parvum serovar 3 str. ATCC ... 700970] gb|AAF30912.1| conserved hypothetical ... [Ureap...[imported] - ... Ureaplasma urealyticum ... Length = 262 ... Query: 1 ...ery: 121 GNSIDMKGLQTNPFESLDKIIAFNEAPIHIVDFHAETTSEKNALFLDFKSKLSLVYGTHT 180 ... ... ... GNSIDMKGLQTNPFESLDKIIAFNEAPIHIVDFHAETTSEKNALFLDFKSKLSLVYGTHT Sbjct: 121 GNSIDMKGLQTNPFESLDKIIAFNEAPIHIVD

Lactate production as representative of the fermentation potential of Corynebacterium glutamicum 2262 in a one-step process.

Science.gov (United States)

Khuat, Hoang Bao Truc; Kaboré, Abdoul Karim; Olmos, Eric; Fick, Michel; Boudrant, Joseph; Goergen, Jean-Louis; Delaunay, Stéphane; Guedon, Emmanuel

2014-01-01

The fermentative properties of thermo-sensitive strain Corynebacterium glutamicum 2262 were investigated in processes coupling aerobic cell growth and the anaerobic fermentation phase. In particular, the influence of two modes of fermentation on the production of lactate, the fermentation product model, was studied. In both processes, lactate was produced in significant amount, 27 g/L in batch culture, and up to 55.8 g/L in fed-batch culture, but the specific production rate in the fed-batch culture was four times lower than that in the batch culture. Compared to other investigated fermentation processes, our strategy resulted in the highest yield of lactic acid from biomass. Lactate production by C. glutamicum 2262 thus revealed the capability of the strain to produce various fermentation products from pyruvate.

Osmolality, temperature, and membrane lipid composition modulate the activity of betaine transporter BetP in Corynebacterium glutamicum

DEFF Research Database (Denmark)

Ozcan, Nuran; Ejsing, Christer S.; Shevchenko, Andrej

2007-01-01

The gram-positive soil bacterium Corynebacterium glutamicum, a major amino acid-producing microorganism in biotechnology, is equipped with several osmoregulated uptake systems for compatible solutes, which is relevant for the physiological response to osmotic stress. The most significant carrier......P activity. We further correlated the change in BetP regulation properties in cells grown at different temperatures to changes in the lipid composition of the plasma membrane. For this purpose, the glycerophospholipidome of C. glutamicum grown at different temperatures was analyzed by mass spectrometry using...... quantitative multiple precursor ion scanning. The molecular composition of glycerophospholipids was strongly affected by the growth temperature. The modulating influence of membrane lipid composition on BetP function was further corroborated by studying the influence of artificial modulation of membrane...

Comparison of two biochemical methods for identifying Corynebacterium pseudotuberculosis isolated from sheep and goats.

Science.gov (United States)

Huerta, Belén; Gómez-Gascón, Lidia; Vela, Ana I; Fernández-Garayzábal, José F; Casamayor, Almudena; Tarradas, Carmen; Maldonado, Alfonso

2013-06-01

The biochemical pattern of Cowan and Steel (BPCS) was compared with a commercial biochemical strip for the identification of Corynebacterium pseudotuberculosis isolated from small ruminants. On 16S rRNA gene sequencing, 40/78 coryneform isolates from the lymph nodes of sheep and goats with lesions resembling caseous lymphadenitis were identified as C. pseudotuberculosis. The sensitivities of the BPCS and the commercial biochemical strip relative to 16S rRNA sequencing were 80% and 85%, and their specificities were 92.1% and 94.7%, respectively; the level of agreement between the BPCS and the commercial biochemical strip was high (κ=0.82). Likelihood ratios for positive and negative results were 10.0 and 0.22 for the BPCS, and 16.0 and 0.16 for the commercial biochemical strip, respectively. These results indicate that the BPCS and the commercial biochemical strip are both useful for identifying C. pseudotuberculosis in veterinary microbiology laboratories. Copyright © 2012 Elsevier Ltd. All rights reserved.

Metabolic engineering of Corynebacterium glutamicum aimed at alternative carbon sources and new products

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Volker Fritz Wendisch

2012-10-01

Full Text Available Corynebacterium glutamicum is well known as the amino acid-producing workhorse of fermentation industry, being used for multi-million-ton scale production of glutamate and lysine for more than 60 years. However, it is only recently that extensive research has focused on engineering it beyond the scope of amino acids. Meanwhile, a variety of corynebacterial strains allows access to alternative carbon sources and/or allows production of a wide range of industrially relevant compounds. Some of these efforts set new standards in terms of titers and productivities achieved whereas others represent a proof-of-principle. These achievements manifest the position of C. glutamicum as an important industrial microorganism with capabilities far beyond the traditional amino acid production. In this review we focus on the state of the art of metabolic engineering of C. glutamicum for utilization of alternative carbon sources, (e.g. coming from wastes and unprocessed sources, and construction of C. glutamicum strains for production of new products such as diamines, organic acids and alcohols.

Difteria pelo Corynebacterium ulcerans: uma zoonose emergente no Brasil e no mundo

Directory of Open Access Journals (Sweden)

Alexandre Alves de Souza de Oliveira Dias

2011-12-01

Full Text Available O artigo revisa a literatura sobre a emergência de infecções humanas causadas por Corynebacterium ulcerans em diversos países, incluindo o Brasil. Foi realizada análise de artigos publicados entre 1926 e 2011 nas bases Medline/PubMed e SciELO, bem como artigos e informes do Ministério da Saúde. Apresenta-se um esquema de triagem, rápido, econômico e de fácil execução, capaz de permitir a realização do diagnóstico presuntivo de C. ulcerans e C. diphtheriae na maioria dos laboratórios brasileiros públicos e privados. A circulação de C. ulcerans em vários países, aliada aos recentes casos de isolamento do patógeno no Rio de Janeiro, é um alerta a clínicos, veterinários e microbiologistas sobre a ocorrência de difteria zoonótica e a circulação do C. ulcerans em regiões urbanas e rurais do território nacional e/ou da América Latina.

Mural endocarditis caused by Corynebacterium mustelae in a dog with a VSD.

Science.gov (United States)

Winter, Randolph L; Gordon, Sonya G; Zhang, Shuping; Hariu, Crystal D; Miller, Matthew W

2014-01-01

A 6 yr old female spayed large Munsterlander was evaluated following a 3 wk history of lethargy, inappetence, intermittent fever, and a recent change to the timing of her previously diagnosed heart murmur. Physical examination revealed marked dehydration, lethargy, and a grade 5/6 to-and-fro heart murmur that was auscultated best at the right sternal border. The dog was febrile, and echocardiography revealed a large, mobile, vegetative lesion in the right ventricular outflow tract associated with a ventricular septal defect (VSD). Mild aortic insufficiency was present. Corynebacterium mustelae (C. mustelae) was isolated from a pooled blood culture. Treatment of infective endocarditis (IE) was initiated along with supportive care, and the patient was discharged 9 days later. The dog remained without clinical signs 132 days after discharge. VSD is rarely mentioned as a predisposing factor for development of IE in veterinary literature; however, this report highlights that dogs with a VSD may be at risk for IE. To the authors' knowledge, this is the first documented case of a canine infection with C. mustelae. Infection with C. mustelae in this case represents a novel agent for IE in the dog.

Activity of disinfectants and biofilm production of Corynebacterium pseudotuberculosis

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Maria da C.A. Sá

2013-11-01

Full Text Available To verify the occurrence of caseous lymphadenitis in sheep and goats on farms of Pernambuco, Brazil, and in animals slaughtered in two Brazilian cities (Petrolina/PE and Juazeiro/BA, and to characterize the susceptibility profile of Corynebacterium pseudotuberculosis to disinfectants and antimicrobials, and its relationship with biofilm production were the objectives of this study. 398 samples were tested for sensitivity to antimicrobial drugs, disinfectants, and biofilm production. Among the 108 samples collected on the properties, 75% were positive for C. pseudotuberculosis. Slaughterhouse samples indicated an occurrence of caseous lymphadenitis in 15.66% and 6.31% for animals slaughtered in Petrolina and Juazeiro respectively. With respect to antimicrobials, the sensitivity obtained was 100% for florfenicol and tetracycline; 99.25% for enrofloxacin, ciprofloxacin and lincomycin; 98.99% for cephalothin; 98.74% for norfloxacin and sulfazotrim; 97.74% for gentamicin; 94.22% for ampicillin; 91.71% for amoxicillin; 91.21% for penicillin G; 89.19% for neomycin and 0% for novobiocin. In analyzes with disinfectants, the efficiency for chlorhexidine was 100%, 97.20% for quaternary ammonium, 87.40% for chlorine and 84.40% for iodine. 75% of the isolates were weak or non-biofilm producers. For the consolidated biofilm, found that iodine decreased biofilm formation in 13 isolates and quaternary ammonia in 11 isolates. The reduction of the biofilm formation was observed for iodine and quaternary ammonium in consolidated biofilm formation in 33% and 28% of the isolates, respectively. The results of this study highlight the importance of establishing measures to prevent and control the disease.

Molecular cloning and expression of Corynebacterium glutamicum genes for amino acid synthesis in Escherichia coli cells

International Nuclear Information System (INIS)

Beskrovnaya, O.Yu.; Fonshtein, M.Yu.; Kolibaba, L.G.; Yankovskii, N.K.; Debabov, V.G.

1989-01-01

Molecular cloning of Corynebacterium glutamicum genes for threonine and lysine synthesis has been done in Escherichia coli cells. The clonal library of EcoRI fragments of chromosomal DNA of C. glutamicum was constructed on the plasmid vector λpSL5. The genes for threonine and lysine synthesis were identified by complementation of E. coli mutations in thrB and lysA genes, respectively. Recombinant plasmids, isolated from independent ThrB + clone have a common 4.1-kb long EcoRI DNA fragment. Hybrid plasmids isolated from LysA + transductants of E. coli have common 2.2 and 3.3 kb long EcoRI fragments of C. glutamicum DNA. The hybrid plasmids consistently transduced the markers thrB + and lysA + . The Southern hybridization analysis showed that the cloned DNA fragments hybridized with the fragments of identical length in C. glutamicum chromosomes

Rich biotin content in lignocellulose biomass plays the key role in determining cellulosic glutamic acid accumulation by Corynebacterium glutamicum.

Science.gov (United States)

Wen, Jingbai; Xiao, Yanqiu; Liu, Ting; Gao, Qiuqiang; Bao, Jie

2018-01-01

Lignocellulose is one of the most promising alternative feedstocks for glutamic acid production as commodity building block chemical, but the efforts by the dominant industrial fermentation strain Corynebacterium glutamicum failed for accumulating glutamic acid using lignocellulose feedstock. We identified the existence of surprisingly high biotin concentration in corn stover hydrolysate as the determining factor for the failure of glutamic acid accumulation by Corynebacterium glutamicum . Under excessive biotin content, induction by penicillin resulted in 41.7 ± 0.1 g/L of glutamic acid with the yield of 0.50 g glutamic acid/g glucose. Our further investigation revealed that corn stover contained 353 ± 16 μg of biotin per kg dry solids, approximately one order of magnitude greater than the biotin in corn grain. Most of the biotin remained stable during the biorefining chain and the rich biotin content in corn stover hydrolysate almost completely blocked the glutamic acid accumulation. This rich biotin existence was found to be a common phenomenon in the wide range of lignocellulose biomass and this may be the key reason why the previous studies failed in cellulosic glutamic acid fermentation from lignocellulose biomass. The extended recording of the complete members of all eight vitamin B compounds in lignocellulose biomass further reveals that the major vitamin B members were also under the high concentration levels even after harsh pretreatment. The high content of biotin in wide range of lignocellulose biomass feedstocks and the corresponding hydrolysates was discovered and it was found to be the key factor in determining the cellulosic glutamic acid accumulation. The highly reserved biotin and the high content of their other vitamin B compounds in biorefining process might act as the potential nutrients to biorefining fermentations. This study creates a new insight that lignocellulose biorefining not only generates inhibitors, but also keeps nutrients

Heterologous expression of the Halothiobacillus neapolitanus carboxysomal gene cluster in Corynebacterium glutamicum.

Science.gov (United States)

Baumgart, Meike; Huber, Isabel; Abdollahzadeh, Iman; Gensch, Thomas; Frunzke, Julia

2017-09-20

Compartmentalization represents a ubiquitous principle used by living organisms to optimize metabolic flux and to avoid detrimental interactions within the cytoplasm. Proteinaceous bacterial microcompartments (BMCs) have therefore created strong interest for the encapsulation of heterologous pathways in microbial model organisms. However, attempts were so far mostly restricted to Escherichia coli. Here, we introduced the carboxysomal gene cluster of Halothiobacillus neapolitanus into the biotechnological platform species Corynebacterium gluta-micum. Transmission electron microscopy, fluorescence microscopy and single molecule localization microscopy suggested the formation of BMC-like structures in cells expressing the complete carboxysome operon or only the shell proteins. Purified carboxysomes consisted of the expected protein components as verified by mass spectrometry. Enzymatic assays revealed the functional production of RuBisCO in C. glutamicum both in the presence and absence of carboxysomal shell proteins. Furthermore, we could show that eYFP is targeted to the carboxysomes by fusion to the large RuBisCO subunit. Overall, this study represents the first transfer of an α-carboxysomal gene cluster into a Gram-positive model species supporting the modularity and orthogonality of these microcompartments, but also identified important challenges which need to be addressed on the way towards biotechnological application. Copyright © 2017 Elsevier B.V. All rights reserved.

Engineering biotin prototrophic Corynebacterium glutamicum strains for amino acid, diamine and carotenoid production.

Science.gov (United States)

Peters-Wendisch, P; Götker, S; Heider, S A E; Komati Reddy, G; Nguyen, A Q; Stansen, K C; Wendisch, V F

2014-12-20

The Gram-positive Corynebacterium glutamicum is auxotrophic for biotin. Besides the biotin uptake system BioYMN and the transcriptional regulator BioQ, this bacterium possesses functional enzymes for the last three reactions of biotin synthesis starting from pimeloyl-CoA. Heterologous expression of bioF from the Gram-negative Escherichia coli enabled biotin synthesis from pimelic acid added to the medium, but expression of bioF together with bioC and bioH from E. coli did not entail biotin prototrophy. Heterologous expression of bioWAFDBI from Bacillus subtilis encoding another biotin synthesis pathway in C. glutamicum allowed for growth in biotin-depleted media. Stable growth of the recombinant was observed without biotin addition for eight transfers to biotin-depleted medium while the empty vector control stopped growth after the first transfer. Expression of bioWAFDBI from B. subtilis in C. glutamicum strains overproducing the amino acids l-lysine and l-arginine, the diamine putrescine, and the carotenoid lycopene, respectively, enabled formation of these products under biotin-depleted conditions. Thus, biotin-prototrophic growth and production by recombinant C. glutamicum were achieved. Copyright © 2014 Elsevier B.V. All rights reserved.

ORF Alignment: NC_002162 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available NC_002162 gi|13357567 >1dd3A 1 106 4 99 2e-11 ... ref|NP_077841.1| ribosomal protein L7/L12 [Ureap...lasma parvum serovar 3 str. ATCC ... 700970] gb|AAF30416.1| ribosomal protein L7/L12 ... [Ureap...L12 ... pir||B82946 ribosomal protein L7/L12 UU011 [imported] - ... Ureap...XIKLVEAG 63 ... LTIEQFIAAIKEMSMLELNDLVKAIETEFGVS ... IKLVEAG Sbjct: 1 ... LTIEQFIAAIKEMSMLELNDLVKAIETEFGVSAAAPVAAAAAPVAAEAPTEVTIKLVEAG 60 ...

A comparative study on phyllosphere nitrogen fixation by newly isolated Corynebacterium sp. & Flavobacterium sp. and their potentialities as biofertilizer.

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Giri, S; Pati, B R

2004-01-01

A number of nitrogen fixing bacteria has been isolated from forest phyllosphere on the basis of nitrogenase activity. Among them two best isolates are selected and identified as Corynebacterium sp. AN1 & Flavobacterium sp. TK2 able to reduce 88 and 132 n mol of acetylene (10(8)cells(-1)h(-1)) respectively. They were grown in large amount and sprayed on the phyllosphere of maize plants as a substitute for nitrogenous fertilizer. Marked improvements in growth and total nitrogen content of the plant have been observed by the application of these nitrogen-fixing bacteria. An average 30-37% increase in yield was obtained, which is nearer to chemical fertilizer treatment. Comparatively better effect was obtained by application of Flavobacterium sp.

Rapid detection of Corynebacterium pseudotuberculosis in clinical samples from sheep.

Science.gov (United States)

Kumar, Jyoti; Tripathi, Bhupendra Nath; Kumar, Rajiv; Sonawane, Ganesh Gangaram; Dixit, Shivendra Kumar

2013-08-01

Corynebacterium pseudotuberculosis, a Gram-positive bacterium is the causative agent of caseous lymphadenitis (CLA), a chronic disease of sheep, goats and other warm blooded animals. In the present study, a total of 1,080 sheep reared under semi-intensive system on organized farms situated in the semi arid tropical region of Rajasthan, India, was clinically examined. Pus samples from superficial lymph nodes of 25 (2.31%) adult sheep showing clinical lesions similar to CLA were collected for laboratory analyses. On the basis of morphological, cultural and biochemical characteristics 12 (48%) bacterial isolates from pus identified it as C. pseudotuberculosis. A polymerase chain reaction (PCR) assay targeting Putative oligopeptide/dipeptide ABC transporter, nicotinamide adenine dinucleotide phosphate (NADP) oxidoreductase coenzyme F420-dependent and proline iminopeptidase (PIP) genes of C. pseudotuberculosis was developed that showed 14 pus samples as positive. All C. pseudotuberculosis isolates were also found positive for these genes in the PCR. The specificity of the PCR products was confirmed by sequencing of the amplified products that showed 98-100% homology with published sequences available in the NCBI database. The present study shows the incidence of CLA as 2.31%, 1.1% and 1.29% based on clinical, bacterial culture and direct pus PCR assay, respectively. The PCR assay was rapid, specific and as significant as bacterial culture in detecting bacteria directly in the clinical pus samples. The PCR assay developed in the study can be applied for the diagnosis and control of CLA. Furthermore, the assay can also be applied to detect C. pseudotuberculosis in various clinical samples.

Isoprenoid Pyrophosphate-Dependent Transcriptional Regulation of Carotenogenesis in Corynebacterium glutamicum

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Petra Peters-Wendisch

2017-04-01

Full Text Available Corynebacterium glutamicum is a natural producer of the C50 carotenoid decaprenoxanthin. The crtEcg0722crtBIYEb operon comprises most of its genes for terpenoid biosynthesis. The MarR-type regulator encoded upstream and in divergent orientation of the carotenoid biosynthesis operon has not yet been characterized. This regulator, named CrtR in this study, is encoded in many actinobacterial genomes co-occurring with terpenoid biosynthesis genes. CrtR was shown to repress the crt operon of C. glutamicum since DNA microarray experiments revealed that transcript levels of crt operon genes were increased 10 to 70-fold in its absence. Transcriptional fusions of a promoter-less gfp gene with the crt operon and crtR promoters confirmed that CrtR represses its own gene and the crt operon. Gel mobility shift assays with purified His-tagged CrtR showed that CrtR binds to a region overlapping with the −10 and −35 promoter sequences of the crt operon. Isoprenoid pyrophosphates interfered with binding of CrtR to its target DNA, a so far unknown mechanism for regulation of carotenogenesis. The molecular details of protein-ligand interactions remain to be studied. Decaprenoxanthin synthesis by C. glutamicum wild type was enhanced 10 to 30-fold upon deletion of crtR and was decreased 5 to 6-fold as result of crtR overexpression. Moreover, deletion of crtR was shown as metabolic engineering strategy to improve production of native and non-native carotenoids including lycopene, β-carotene, C.p. 450 and sarcinaxanthin.

Evaluation of three methods for DNA fingerprinting of Corynebacterium pseudotuberculosis strains isolated from goats in Poland.

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Stefańska, Ilona; Rzewuska, Magdalena; Binek, Marian

2008-01-01

Phenotypic approaches based on metabolic and biological characteristics of Corynebacterium pseudotuberculosis have been limited due to insufficient discrimination between closely related isolates. In this paper we present performance and convenience of three molecular typing methods: BOX-PCR, random amplification of polymorphic DNA (RAPD) and amplification of DNA fragments surrounding rare restriction site (ADSRRS-fingerprinting) in genome analysis of these bacteria. Among examined 61 strains there were distinguished four, eight and 10 different genotypes by BOX-PCR, RAPD and ADSRRS-fingerprinting, respectively. The value of discrimination index was the lowest for BOX-PCR (D = 0.265), much bigger for RAPD (D = 0.539) and the highest for ADSRRS-fingerprinting (D = 0.604). The good discriminatory ability and reproducibility of RAPD and ADSRRS-fingerprinting indicates that those techniques may be particularly applied for epidemiological studies of C. pseudotuberculosis isolates. We found that ADSRRS-fingerprinting is a rapid method offering good discrimination power, excellent reproducibility and may be applied for epidemiological studies of intraspecific genetic relatedness of C. pseudotuberculosis strains.

Recovery of high-purity metallic Pd from Pd(II)-sorbed biosorbents by incineration.

Science.gov (United States)

Won, Sung Wook; Lim, Areum; Yun, Yeoung-Sang

2013-06-01

This work reports a direct way to recover metallic palladium with high purity from Pd(II)-sorbed polyethylenimine-modified Corynebacterium glutamicum biosorbent using a combined method of biosorption and incineration. This study is focused on the incineration part which affects the purity of recovered Pd. The incineration temperature and the amount of Pd loaded on the biosorbent were considered as major factors in the incineration process, and their effects were examined. The results showed that both factors significantly affected the enhancement of the recovery efficiency and purity of the recovered Pd. SEM-EDX and XRD analyses were used to confirm that Pd phase existed in the ash. As a result, the recovered Pd was changed from PdO to zero-valent Pd as the incineration temperature was increased from 600 to 900°C. Almost 100% pure metallic Pd was recovered with recovery efficiency above 99.0% under the conditions of 900°C and 136.9 mg/g. Copyright © 2013 Elsevier Ltd. All rights reserved.

High-resolution detection of DNA binding sites of the global transcriptional regulator GlxR in Corynebacterium glutamicum

DEFF Research Database (Denmark)

Jungwirth, Britta; Sala, Claudia; Kohl, Thomas A

2013-01-01

of the 6C non-coding RNA gene and to non-canonical DNA binding sites within protein-coding regions. The present study underlines the dynamics within the GlxR regulon by identifying in vivo targets during growth on glucose and contributes to the expansion of knowledge of this important transcriptional......The transcriptional regulator GlxR has been characterized as a global hub within the gene-regulatory network of Corynebacterium glutamicum. Chromatin immunoprecipitation with a specific anti-GlxR antibody and subsequent high-throughput sequencing (ChIP-seq) was applied to C. glutamicum to get new...... mapping of these data on the genome sequence of C. glutamicum, 107 enriched DNA fragments were detected from cells grown with glucose as carbon source. GlxR binding sites were identified in the sequence of 79 enriched DNA fragments, of which 21 sites were not previously reported. Electrophoretic mobility...

Evaluation of the solar water disinfection process (SODIS) against Cryptosporidium parvum using a 25-L static solar reactor fitted with a compound parabolic collector (CPC).

Science.gov (United States)

Fontán-Sainz, María; Gómez-Couso, Hipólito; Fernández-Ibáñez, Pilar; Ares-Mazás, Elvira

2012-02-01

Water samples of 0, 5, and 30 nephelometric turbidity units (NTU) spiked with Cryptosporidium parvum oocysts were exposed to natural sunlight using a 25-L static solar reactor fitted with a compound parabolic collector (CPC). The global oocyst viability was calculated by the evaluation of the inclusion/exclusion of the fluorogenic vital dye propidium iodide and the spontaneous excystation. After an exposure time of 8 hours, the global oocyst viabilities were 21.8 ± 3.1%, 31.3 ± 12.9%, and 45.0 ± 10.0% for turbidity levels of 0, 5, and 30 NTU, respectively, and these values were significantly lower (P 10 times).

Surgical Site Infection by Corynebacterium macginleyi in a Patient with Neurofibromatosis Type 1

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Bruno Cacopardo

2013-01-01

Full Text Available Corynebacterium (C. macginleyi is a gram positive, lipophilic rod, usually considered a colonizer of skin and mucosal surfaces. Several reports have associated C. macginleyi with ocular infections, such as conjunctivitis and endophthalmitis. However, even if rare, extraocular infections from C. macginleyi may occur, especially among immunocompromised patients and patients with indwelling medical devices. We report herein the first case of surgical site infection by C. macginleyi after orthopaedic surgery for the correction of kyphoscoliosis in a patient with neurofibromatosis type 1. Our patient developed a nodular granulomatous lesion of about two centimetres along the surgical scar, at the level of C4-C5, with purulent discharge and formation of a fistulous tract. Cervical magnetic resonance imaging showed the presence of a two-centimetre fluid pocket in the subcutaneous tissue. Several swabs were collected from the borders of the lesion as well as from the exudate, with isolation of C. macginleyi. The isolate was susceptible to beta-lactams, cotrimoxazole, linezolid, and glycopeptides but resistant to quinolones, third-generation cephalosporins, and erythromycin. Two 30-day courses of antibiotic therapy with amoxicillin/clavulanate (1 g three times/day and cotrimoxazole (800/160 mg twice a day were administered, obtaining a complete healing of the lesion.

Rat strains differ in susceptibility to Ureaplasma parvum-induced urinary tract infection and struvite stone formation.

Science.gov (United States)

Reyes, Leticia; Reinhard, Mary; O'donell, L J; Stevens, Janet; Brown, Mary B

2006-12-01

Individuals with struvite uroliths are susceptible to recurrent urinary tract infections (UTI), sepsis, and renal disease. Unfortunately, little is known about the host-specific factors that predispose to this disease. In order to develop a rodent model that can address this problem, we inoculated female Fischer 344 (F344), Lewis (LEW), Sprague-Dawley (SD), and Wistar (WIS) rats with a host-adapted strain of Ureaplasma parvum. Animals were necropsied at 2 weeks postinoculation; 100% of F344, 42% of SD, 10% of LEW, and 10% of WIS rats remained infected. Severe bladder lesions and struvite calculi were seen in 64% of F344 rats; in other rat strains, bladder lesions were mild or absent. F344 rats with struvite uroliths had the highest urinary levels of proinflammatory cytokines, such as GRO/KC, interleukin-1alpha (IL-1alpha), and IL-1beta. F344 rats without struvite stones at necropsy had milder bladder lesions and significantly lower urinary levels of proinflammatory cytokines but a more prominent inflammatory response than did other rat strains. Based on our results, struvite stone formation is linked to a robust inflammatory response that does not resolve UTI but instead promotes damage to surrounding tissues.

In Vivo Roles of Fatty Acid Biosynthesis Enzymes in Biosynthesis of Biotin and α-Lipoic Acid in Corynebacterium glutamicum.

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Ikeda, Masato; Nagashima, Takashi; Nakamura, Eri; Kato, Ryosuke; Ohshita, Masakazu; Hayashi, Mikiro; Takeno, Seiki

2017-10-01

For fatty acid biosynthesis, Corynebacterium glutamicum uses two type I fatty acid synthases (FAS-I), FasA and FasB, in addition to acetyl-coenzyme A (CoA) carboxylase (ACC) consisting of AccBC, AccD1, and AccE. The in vivo roles of the enzymes in supplying precursors for biotin and α-lipoic acid remain unclear. Here, we report genetic evidence demonstrating that the biosynthesis of these cofactors is linked to fatty acid biosynthesis through the FAS-I pathway. For this study, we used wild-type C. glutamicum and its derived biotin vitamer producer BFI-5, which was engineered to express Escherichia coli bioBF and Bacillus subtilis bioI Disruption of either fasA or fasB in strain BFI-5 led to decreased production of biotin vitamers, whereas its amplification contributed to increased production, with a larger impact of fasA in both cases. Double disruptions of fasA and fasB resulted in no biotin vitamer production. The acc genes showed a positive effect on production when amplified simultaneously. Augmented fatty acid biosynthesis was also reflected in pimelic acid production when carbon flow was blocked at the BioF reaction. These results indicate that carbon flow down the FAS-I pathway is destined for channeling into the biotin biosynthesis pathway, and that FasA in particular has a significant impact on precursor supply. In contrast, fasB disruption resulted in auxotrophy for lipoic acid or its precursor octanoic acid in both wild-type and BFI-5 strains. The phenotypes were fully complemented by plasmid-mediated expression of fasB but not fasA These results reveal that FasB plays a specific physiological role in lipoic acid biosynthesis in C. glutamicum IMPORTANCE For the de novo biosynthesis of fatty acids, C. glutamicum exceptionally uses a eukaryotic multifunctional type I fatty acid synthase (FAS-I) system comprising FasA and FasB, in contrast to most bacteria, such as E. coli and B. subtilis , which use an individual nonaggregating type II fatty acid synthase

Foetal Ureaplasma parvum bacteraemia as a function of gestation-dependent complement insufficiency: Evidence from a sheep model of pregnancy.

Science.gov (United States)

Kemp, Matthew W; Ahmed, Shatha; Beeton, Michael L; Payne, Matthew S; Saito, Masatoshi; Miura, Yuichiro; Usuda, Haruo; Kallapur, Suhas G; Kramer, Boris W; Stock, Sarah J; Jobe, Alan H; Newnham, John P; Spiller, Owen B

2017-01-01

Complement is a central defence against sepsis, and increasing complement insufficiency in neonates of greater prematurity may predispose to increased sepsis. Ureaplasma spp. are the most frequently cultured bacteria from preterm blood samples. A sheep model of intrauterine Ureaplasma parvum infection was used to examine in vivo Ureaplasma bacteraemia at early and late gestational ages. Complement function and Ureaplasma killing assays were used to determine the correlation between complement potency and bactericidal activity of sera ex vivo. Ureaplasma was cultured from 50% of 95-day gestation lamb cord blood samples compared to 10% of 125-day gestation lambs. Bactericidal activity increased with increased gestational age, and a direct correlation between functional complement activity and bactericidal activity (R 2 =.86; PUreaplasma bacteraemia in vivo was confined to early preterm lambs with low complement function, but Ureaplasma infection itself did not diminish complement levels. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

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I. Fernández-Natal

2016-03-01

Full Text Available During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β-lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species.

[Corynebacterium imitans isolated from blood culture in a patient with suspected bacteremia - the first isolation from human clinical material in the Czech Republic].

Science.gov (United States)

JeŽek, Petr; Zavadilová, Jana; Kolínská, Renáta; Švec, Pavel; Guttwirth, Jiří; Petráš, Petr

2014-09-01

The current view of the clinical importance of nondiphtherial corynebacteria recovered from human clinical material has changed considerably in recent decades; in many cases, a direct etiological role is assumed or has already been demonstrated. Presented is a case of suspected bacteremia in a hospitalized elderly woman with isolation of the very rare species Corynebacterium imitans from blood culture. However, the etiological significance of the isolated microorganism remains unclear. The aim was not to demonstrate the etiological significance of the isolated C. imitans strain but to report the occurrence of this very rare species which is considered to be the first isolation from humans in the Czech Republic.

Recent advances in the metabolic engineering of Corynebacterium glutamicum for the production of lactate and succinate from renewable resources.

Science.gov (United States)

Tsuge, Yota; Hasunuma, Tomohisa; Kondo, Akihiko

2015-03-01

Recent increasing attention to environmental issues and the shortage of oil resources have spurred political and industrial interest in the development of environmental friendly and cost-effective processes for the production of bio-based chemicals from renewable resources. Thus, microbial production of commercially important chemicals is viewed as a desirable way to replace current petrochemical production. Corynebacterium glutamicum, a Gram-positive soil bacterium, is one of the most important industrial microorganisms as a platform for the production of various amino acids. Recent research has explored the use of C. glutamicum as a potential cell factory for producing organic acids such as lactate and succinate, both of which are commercially important bulk chemicals. Here, we summarize current understanding in this field and recent metabolic engineering efforts to develop C. glutamicum strains that efficiently produce L- and D-lactate, and succinate from renewable resources.

The role of lipids and salts in two-dimensional crystallization of the glycine-betaine transporter BetP from Corynebacterium glutamicum

DEFF Research Database (Denmark)

Tsai, Ching-Ju; Ejsing, Christer S.; Shevchenko, Andrej

2007-01-01

The osmoregulated and chill-sensitive glycine-betaine transporter (BetP) from Corynebacterium glutamicum was reconstituted into lipids to form two-dimensional (2D) crystals. The sensitivity of BetP partly bases on its interaction with lipids. Here we demonstrate that lipids and salts influence...... crystal morphology and crystallinity of a C-terminally truncated BetP. The salt type and concentration during crystallization determined whether crystals grew in the form of planar-tubes, sheets or vesicles, while the lipid type influenced crystal packing and order. Three different lipid preparations...... for 2D crystallization were compared. Only the use of lipids extracted from C. glutamicum cells led to the formation of large, well-ordered crystalline areas. To understand the lipid-derived influence on crystallinity, lipid extracts from different stages of the crystallization process were analyzed...

Inhibitory Activities of Epidermal Growth Factor Receptor Tyrosine Kinase-Targeted Dihydroxyisoflavone and Trihydroxydeoxybenzoin Derivatives on Sarcocystis neurona, Neospora caninum, and Cryptosporidium parvum Development

Science.gov (United States)

Gargala, G.; Baishanbo, A.; Favennec, L.; François, A.; Ballet, J. J.; Rossignol, J.-F.

2005-01-01

Several gene sequences of parasitic protozoa belonging to protein kinase gene families and epidermal growth factor (EGF)-like peptides, which act via binding to receptor tyrosine kinases of the EGF receptor (EGFR) family, appear to mediate host-protozoan interactions. As a clue to EGFR protein tyrosine kinase (PTK) mediation and a novel approach for identifying anticoccidial agents, activities against Sarcocystis neurona, Neospora caninum, and Cryptosporidium parvum grown in BM and HCT-8 cell cultures of 52 EGFR PTK inhibitor isoflavone analogs (dihydroxyisoflavone and trihydroxydeoxybenzoine derivatives) were investigated. Their cytotoxicities against host cells were either absent, mild, or moderate by a nitroblue tetrazolium test. At concentrations ranging from 5 to 10 μg/ml, 20 and 5 analogs, including RM-6427 and RM-6428, exhibited an in vitro inhibitory effect of ≥95% against at least one parasite or against all three, respectively. In immunosuppressed Cryptosporidium parvum-infected Mongolian gerbils orally treated with either 200 or 400 mg of agent RM-6427/kg of body weight/day for 8 days, fecal microscopic oocyst shedding was abolished in 6/10 animals (P of 0.05, respectively). After RM-6427 therapy (200 mg/kg/day for 8 days), the reduction in the ratio of animals with intracellular parasites was nearly significant in ileum (P = 0.067) and more marked in the biliary tract (P < 0.0013) than after nitazoxanide or paromomycin treatment (0.05 < P < 0.004). RM-6428 treatment at a regimen of 400 mg/kg/day for 12 days inhibited oocyst shedding, measured using flow cytometry from day 4 (P < 0.05) to day 12 (P < 0.02) of therapy, when 2/15 animals had no shedding (P < 0.0001) and 11/15 were free of gut and/or biliary tract parasites (P < 0.01). No mucosal alteration was microscopically observed for treated or untreated infected gerbils. To our knowledge, this report is the first to suggest that the isoflavone class of agents has the potential for

Glucan: mechanisms involved in its radioprotective effect

International Nuclear Information System (INIS)

Patchen, M.L.; D'Alesandro, M.M.; Brook, I.; Blakely, W.F.; MacVittie, T.J.

1987-01-01

It has generally been accepted that most biologically derived agents that are radioprotective in the hemopoietic-syndrome dose range (eg, endotoxin, Bacillus Calmette Guerin, Corynebacterium parvum, etc) exert their beneficial properties by enhancing hemopoietic recovery and hence, by regenerating the host's ability to resist life-threatening opportunistic infections. However, using glucan as a hemopoietic stimulant/radioprotectant, we have demonstrated that host resistance to opportunistic infection is enhanced in these mice even prior to the detection of significant hemopoietic regeneration. This early enhanced resistance to microbial invasion in glucan-treated irradiated mice could be correlated with enhanced and/or prolonged macrophage (but not granulocyte) function. These results suggest that early after irradiation glucan may mediate its radioprotection by enhancing resistance to microbial invasion via mechanisms not necessarily predicated on hemopoietic recovery. In addition, preliminary evidence suggests that glucan can also function as an effective free-radical scavenger. Because macrophages have been shown to selectively phagocytize and sequester glucan, the possibility that these specific cells may be protected by virtue of glucan's scavenging ability is also suggested

Lasting engraftment of histoincompatible bone marrow cells in dogs

International Nuclear Information System (INIS)

Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.C.; Zurcher, C.; van Bekkum, D.W.

1981-01-01

Conditioning protocols were tested for their efficacy in increasng the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradiation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-h interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplotype-mismatched donor. Possibilities for further improvement of this protocol are discussed

Lasting engraftment of histoincompatible bone marrow cells in dogs

Energy Technology Data Exchange (ETDEWEB)

Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.C.; Zurcher, C.; van Bekkum, D.W.

1981-05-01

Conditioning protocols were tested for their efficacy in increasng the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradiation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-h interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplotype-mismatched donor. Possibilities for further improvement of this protocol are discussed.

Lasting engraftment of histoincompatible bone marrow cells in dogs

Energy Technology Data Exchange (ETDEWEB)

Vriesendorp, H.M.; Klapwijk, W.M.; van Kessel, A.M.; Zurcher, C.; van Bekkum, D.W.

1981-05-01

Conditioning protocols were tested for their efficacy in increasing the incidence of engraftment of histoincompatible dog bone marrow cells. Cyclophosphamide and total body irradation (TBI), Corynebacterium parvum and TBI, a 3- or 5-day delayed transfusion of bone marrow cells after TBI, or an increase in the number of donor bone marrow cells or lymphocytes appeared to be ineffective. These protocols were previously reported to promote recovery of splenic hemopoiesis in mice in short-term assays. The noted discrepancy between studies with mice and dogs invalidated allogeneic resistance as measured in the mouse spleen assay as a model for bone marrow allograft rejection. Intravenous treatment with silica particles or L-asparaginase did improve the engraftment rate after 7.5 Gy TBI. Low efficiency and significant extra toxicity restrict the applicability of these procedures. The most promising conditioning schedule found appeared to be two fractions of 6.0 Gy TBI separated by a 72-hr interval. Prolonged survival was noted after transplantation of bone marrow cells from a one-DLA haplo-type-mismatched donor. Possibilities for further improvement of this protocol are discussed.

Corynebacterium diphtheriae methionine sulfoxide reductase a exploits a unique mycothiol redox relay mechanism.

Science.gov (United States)

Tossounian, Maria-Armineh; Pedre, Brandán; Wahni, Khadija; Erdogan, Huriye; Vertommen, Didier; Van Molle, Inge; Messens, Joris

2015-05-01

Methionine sulfoxide reductases are conserved enzymes that reduce oxidized methionines in proteins and play a pivotal role in cellular redox signaling. We have unraveled the redox relay mechanisms of methionine sulfoxide reductase A of the pathogen Corynebacterium diphtheriae (Cd-MsrA) and shown that this enzyme is coupled to two independent redox relay pathways. Steady-state kinetics combined with mass spectrometry of Cd-MsrA mutants give a view of the essential cysteine residues for catalysis. Cd-MsrA combines a nucleophilic cysteine sulfenylation reaction with an intramolecular disulfide bond cascade linked to the thioredoxin pathway. Within this cascade, the oxidative equivalents are transferred to the surface of the protein while releasing the reduced substrate. Alternatively, MsrA catalyzes methionine sulfoxide reduction linked to the mycothiol/mycoredoxin-1 pathway. After the nucleophilic cysteine sulfenylation reaction, MsrA forms a mixed disulfide with mycothiol, which is transferred via a thiol disulfide relay mechanism to a second cysteine for reduction by mycoredoxin-1. With x-ray crystallography, we visualize two essential intermediates of the thioredoxin relay mechanism and a cacodylate molecule mimicking the substrate interactions in the active site. The interplay of both redox pathways in redox signaling regulation forms the basis for further research into the oxidative stress response of this pathogen. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among Young Children with and without Diarrhea in Dar es Salaam, Tanzania.

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Marit G Tellevik

Full Text Available Although enteroparasites are common causes of diarrheal illness, few studies have been performed among children in Tanzania. This study aimed to investigate the prevalence of Cryptosporidium parvum/hominis, Entamoeba histolytica and Giardia lamblia among young children in Dar es Salaam, Tanzania, and identify risk factors for infection.We performed an unmatched case-control study among children 12 months (P = 0.003; OR = 3.5; 95% CI: 1.5-7.8. Among children aged 7-12 months, those who were breastfed had lower prevalence of G. lamblia infection than those who had been weaned (P = 0.012.Cryptosporidium infection is common among young Tanzanian children with diarrhea, particularly those living with HIV, and infection is more frequent during the rainy season. G. lamblia is frequently implicated in asymptomatic infections, but rarely causes overt diarrheal illness, and its prevalence increases with age.

Aggregative adherent strains of Corynebacterium pseudodiphtheriticum enter and survive within HEp-2 epithelial cells

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Monica Cristina de Souza

2012-06-01

Full Text Available Corynebacterium pseudodiphtheriticum is a well-known human pathogen that mainly causes respiratory disease and is associated with high mortality in compromised hosts. Little is known about the virulence factors and pathogenesis of C. pseudodiphtheriticum. In this study, cultured human epithelial (HEp-2 cells were used to analyse the adherence pattern, internalisation and intracellular survival of the ATCC 10700 type strain and two additional clinical isolates. These microorganisms exhibited an aggregative adherence-like pattern to HEp-2 cells characterised by clumps of bacteria with a "stacked-brick" appearance. The differences in the ability of these microorganisms to invade and survive within HEp-2 cells and replicate in the extracellular environment up to 24 h post infection were evaluated. The fluorescent actin staining test demonstrated that actin polymerisation is involved in the internalisation of the C. pseudodiphtheriticum strains. The depolymerisation of microfilaments by cytochalasin E significantly reduced the internalisation of C. pseudodiphtheriticum by HEp-2 cells. Bacterial internalisation and cytoskeletal rearrangement seemed to be partially triggered by the activation of tyrosine kinase activity. Although C. pseudodiphtheriticum strains did not demonstrate an ability to replicate intracellularly, HEp-2 cells were unable to fully clear the pathogen within 24 h. These characteristics may explain how some C. pseudodiphtheriticum strains cause severe infection in human patients.

Analysis of different DNA fragments of Corynebacterium glutamicum complementing dapE of Escherichia coli.

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Wehrmann, A; Eggeling, L; Sahm, H

1994-12-01

In Corynebacterium glutamicum L-lysine is synthesized simultaneously via the succinylase and dehydrogenase variant of the diaminopimelate pathway. Starting from a strain with a disrupted dehydrogenase gene, three different-sized DNA fragments were isolated which complemented defective Escherichia coli mutants in the succinylase pathway. Enzyme studies revealed that in one case the dehydrogenase gene had apparently been reconstituted in the heterologous host. The two other fragments resulted in desuccinylase activity; one of them additionally in succinylase activity. However, the physical analysis showed that structural changes had taken place in all fragments. Using a probe derived from one of the fragments we isolated a 3.4 kb BamHI DNA fragment without selective pressure (by colony hybridization). This was structurally intact and proved functionally to result in tenfold desuccinylase overexpression. The nucleotide sequence of a 1966 bp fragment revealed the presence of one truncated open reading frame of unknown function and that of dapE encoding N-succinyl diaminopimelate desuccinylase (EC 3.5.1.18). The deduced amino acid sequence of the dapE gene product shares 23% identical residues with that from E. coli. The C. glutamicum gene now available is the first gene from the succinylase branch of lysine synthesis of this biotechnologically important organism.

Rat Strains Differ in Susceptibility to Ureaplasma parvum-Induced Urinary Tract Infection and Struvite Stone Formation▿

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Reyes, Leticia; Reinhard, Mary; O'Donell, L. J.; Stevens, Janet; Brown, Mary B.

2006-01-01

Individuals with struvite uroliths are susceptible to recurrent urinary tract infections (UTI), sepsis, and renal disease. Unfortunately, little is known about the host-specific factors that predispose to this disease. In order to develop a rodent model that can address this problem, we inoculated female Fischer 344 (F344), Lewis (LEW), Sprague-Dawley (SD), and Wistar (WIS) rats with a host-adapted strain of Ureaplasma parvum. Animals were necropsied at 2 weeks postinoculation; 100% of F344, 42% of SD, 10% of LEW, and 10% of WIS rats remained infected. Severe bladder lesions and struvite calculi were seen in 64% of F344 rats; in other rat strains, bladder lesions were mild or absent. F344 rats with struvite uroliths had the highest urinary levels of proinflammatory cytokines, such as GRO/KC, interleukin-1α (IL-1α), and IL-1β. F344 rats without struvite stones at necropsy had milder bladder lesions and significantly lower urinary levels of proinflammatory cytokines but a more prominent inflammatory response than did other rat strains. Based on our results, struvite stone formation is linked to a robust inflammatory response that does not resolve UTI but instead promotes damage to surrounding tissues. PMID:16982825

Effectiveness of standard UV depuration at inactivating Cryptosporidium parvum recovered from spiked Pacific oysters (Crassostrea gigas).

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Sunnotel, O; Snelling, W J; McDonough, N; Browne, L; Moore, J E; Dooley, J S G; Lowery, C J

2007-08-01

When filter-feeding shellfish are consumed raw, because of their ability to concentrate and store waterborne pathogens, they are being increasingly associated with human gastroenteritis and have become recognized as important pathogen vectors. In the shellfish industry, UV depuration procedures are mandatory to reduce pathogen levels prior to human consumption. However, these guidelines are based around more susceptible fecal coliforms and Salmonella spp. and do not consider Cryptosporidium spp., which have significant resistance to environmental stresses. Thus, there is an urgent need to evaluate the efficiency of standard UV depuration against the survival of Cryptosporidium recovered from shellfish. Our study found that in industrial-scale shellfish depuration treatment tanks, standard UV treatment resulted in a 13-fold inactivation of recovered, viable C. parvum oocysts from spiked (1 x 10(6) oocysts liter (-1)) Pacific oysters. Depuration at half power also significantly reduced (P oysters. While UV treatment resulted in significant reductions of recovered viable oocysts, low numbers of viable oocysts were still recovered from oysters after depuration, making their consumption when raw a public health risk. Our study highlights the need for increased periodic monitoring programs for shellfish harvesting sites, improved depuration procedures, and revised microbial quality control parameters, including Cryptosporidium assessment, to minimize the risk of cryptosporidiosis.

Associations between water physicochemistry and Prymnesium parvum presence, abundance, and toxicity in west Texas reservoirs

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VanLandeghem, Matthew M.; Farooqi, Mukhtar; Southard, Greg M.; Patino, Reynaldo

2015-01-01

Toxic blooms of golden alga (Prymnesium parvum) have caused substantial ecological and economic harm in freshwater and marine systems throughout the world. In North America, toxic blooms have impacted freshwater systems including large reservoirs. Management of water chemistry is one proposed option for golden alga control in these systems. The main objective of this study was to assess physicochemical characteristics of water that influence golden alga presence, abundance, and toxicity in the Upper Colorado River basin (UCR) in Texas. The UCR contains reservoirs that have experienced repeated blooms and other reservoirs where golden alga is present but has not been toxic. We quantified golden alga abundance (hemocytometer counts), ichthyotoxicity (bioassay), and water chemistry (surface grab samples) at three impacted reservoirs on the Colorado River; two reference reservoirs on the Concho River; and three sites at the confluence of these rivers. Sampling occurred monthly from January 2010 to July 2011. Impacted sites were characterized by higher specific conductance, calcium and magnesium hardness, and fluoride than reference and confluence sites. At impacted sites, golden alga abundance and toxicity were positively associated with salinity-related variables and blooms peaked at ~10°C and generally did not occur above 20°C. Overall, these findings suggest management of land and water use to reduce hardness or salinity could produce unfavorable conditions for golden alga.

Confirmed detection of Cyclospora cayetanesis, Encephalitozoon intestinalis and Cryptosporidium parvum in water used for drinking.

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Dowd, Scot E; John, David; Eliopolus, James; Gerba, Charles P; Naranjo, Jaime; Klein, Robert; López, Beatriz; de Mejía, Maricruz; Mendoza, Carlos E; Pepper, Ian L

2003-09-01

Human enteropathogenic microsporidia (HEM), Cryptosporidium parvum, Cyclospora cayetanesis, and Giardia lamblia are associated with gastrointestinal disease in humans. To date, the mode of transmission and environmental occurrence of HEM (Encephalitozoon intestinalis and Enterocytozoon bieneusi) and Cyclospora cayetanesis have not been fully elucidated due to lack of sensitive and specific environmental screening methods. The present study was undertaken with recently developed methods, to screen various water sources used for public consumption in rural areas around the city of Guatemala. Water concentrates collected in these areas were subjected to community DNA extraction followed by PCR amplification, PCR sequencing and computer database homology comparison (CDHC). All water samples screened in this study had been previously confirmed positive for Giardia spp. by immunofluorescent assay (IFA). Of the 12 water concentrates screened, 6 showed amplification of microsporidial SSU-rDNA and were subsequently confirmed to be Encephalitozoon intestinalis. Five of the samples allowed for amplification of Cyclospora 18S-rDNA; three of these were confirmed to be Cyclospora cayetanesis while two could not be identified because of inadequate sequence information. Thus, this study represents the first confirmed identification of Cyclospora cayetanesis and Encephalitozoon intestinalis in source water used for consumption. The fact that the waters tested may be used for human consumption indicates that these emerging protozoa may be transmitted by ingestion of contaminated water.

Technetium-99m labeling and fibronectin binding ability of Corynebacterium diphtheriae

International Nuclear Information System (INIS)

Souza, S.M.S.; Nagao, P.E.; Bernardo-Filho, M.; Pereira, G.A.; Napoleao, F.; Andrade, A.F.B.; Hirata Junior, R.; Mattos-Guaraldi, A.L.

2004-01-01

The use of radionuclides has permitted advances in areas of clinical and scientific knowledge. Several molecules and cells have been labelled with Technetium-99m ( 99m Tc). The stannous chloride (SnCl 2 ) has a significant influence on the labeling and stability of 99m Tc radiotracers. The frequent risk of diphtheria epidemics has intensified interest in the virulence factors of Corynebacterium diphtheriae. Although studies have looked at potential adhesins including haemagglutinins and exposed sugar residues, the molecular basis of mechanisms of adherence remains unclear. Adherence of pathogens to mammalian tissues may be mediated by fibronectin (FN) found in body fluids, matrix of connective tissues, and cell surfaces. In the present study we evaluated the binding ability to human plasma FN by 99m Tc labeled-C.diphtheriae. Due to adverse effects of stannous ions, microorganisms were submitted to survival and filamentation induction assays. Data showed a dose dependent susceptibility to SnCl 2 bactericidal effects. Cell filamentation was observed for concentrations of SnCl 2 > 110 μg/ml. Adherence levels of 99m Tc labelled 241strain to coverslips coated with 20 μg/ml FN were higher (P = 0.0037) than coated with bovine serum albumin. FN binding by the sucrose fermenting 241 C. diphtheriae strain (8.9% + 2.6) was significantly lower (P=0.0139) than Staphylococcus aureus Cowan I strain (34.1% ± 1.2). Therefore, bacterial 99m Tc labeling represents an additional tool that may contribute to the comprehension of C. diphtheriae interactions with host receptors such as FN that act as biological organizers by holding bacterial cells in position and guiding their migration. (author)

Metabolic Design of Corynebacterium glutamicum for Production of l-Cysteine with Consideration of Sulfur-Supplemented Animal Feed.

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Joo, Young-Chul; Hyeon, Jeong Eun; Han, Sung Ok

2017-06-14

l-Cysteine is a valuable sulfur-containing amino acid widely used as a nutrition supplement in industrial food production, agriculture, and animal feed. However, this amino acid is mostly produced by acid hydrolysis and extraction from human or animal hairs. In this study, we constructed recombinant Corynebacterium glutamicum strains that overexpress combinatorial genes for l-cysteine production. The aims of this work were to investigate the effect of the combined overexpression of serine acetyltransferase (CysE), O-acetylserine sulfhydrylase (CysK), and the transcriptional regulator CysR on l-cysteine production. The CysR-overexpressing strain accumulated approximately 2.7-fold more intracellular sulfide than the control strain (empty pMT-tac vector). Moreover, in the resulting CysEKR recombinant strain, combinatorial overexpression of genes involved in l-cysteine production successfully enhanced its production by approximately 3.0-fold relative to that in the control strain. This study demonstrates a biotechnological model for the production of animal feed supplements such as l-cysteine using metabolically engineered C. glutamicum.

Corynebacterium diphtheriae in a free-roaming red fox: case report and historical review on diphtheria in animals.

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Sing, Andreas; Konrad, Regina; Meinel, Dominik M; Mauder, Norman; Schwabe, Ingo; Sting, Reinhard

2016-08-01

Corynebacterium diphtheriae, the classical causative agent of diphtheria, is considered to be nearly restricted to humans. Here we report the first finding of a non-toxigenic C. diphtheriae biovar belfanti strain in a free-roaming wild animal. The strain obtained from the subcutis and mammary gland of a dead red fox (Vulpes vulpes) was characterized by biochemical and molecular methods including MALDI-TOF and Multi Locus Sequence Typing. Since C. diphtheriae infections of animals, usually with close contact to humans, are reported only very rarely, an intense review comprising also scientific literature from the beginning of the 20th century was performed. Besides the present case, only 11 previously reported C. diphtheriae animal infections could be verified using current scientific criteria. Our report is the first on the isolation of C. diphtheriae from a wildlife animal without any previous human contact. In contrast, the very few unambiguous publications on C. diphtheriae in animals referred to livestock or pet animals with close human contact. C. diphtheriae carriage in animals has to be considered as an exceptionally rare event.

Expression, purification, crystallization and preliminary crystallographic analysis of SpaA, a major pilin from Corynebacterium diphtheriae

International Nuclear Information System (INIS)

Kang, Hae Joo; Paterson, Neil G.; Baker, Edward N.

2009-01-01

SpaA, one of the major pilins of C. diphtheriae, has been expressed, purified and crystallized and X-ray diffraction data have been collected to 1.6 Å resolution. Bacterial pili are cell-surface organelles that are critically involved in adhesion to host cells, leading to the colonization of host tissues and the establishment of infections. Whereas the pili of Gram-negative bacteria have been extensively studied, those of Gram-positive bacteria came to light only recently after the discovery and characterization of Corynebacterium diphtheriae pili. These newly discovered pili are formed by the covalent polymerization of pilin subunits catalyzed by sortase enzymes, making them fundamentally different from the noncovalent pilin assemblies of Gram-negative bacteria. Here, the expression, crystallization and preliminary crystallographic analysis of SpaA, which forms the shaft of one of the three types of pili expressed by C. diphtheriae, are reported. SpaA 53–486 crystals diffracted to 1.6 Å resolution and belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 34.9, b = 64.1, c = 198.7 Å, α = β = γ = 90°

Improvement of succinate production by release of end-product inhibition in Corynebacterium glutamicum.

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Chung, Soon-Chun; Park, Joon-Song; Yun, Jiae; Park, Jin Hwan

2017-03-01

Succinate is a renewable-based platform chemical that may be used to produce a wide range of chemicals including 1,4-butanediol, tetrahydrofurane, and γ-butyrolactone. However, industrial fermentation of organic acids is often subject to end-product inhibition, which significantly retards cell growth and limits metabolic activities and final productivity. In this study, we report the development of metabolically engineered Corynebacterium glutamicum for high production of succinate by release of end-product inhibition coupled with an increase of key metabolic flux. It was found that the rates of glucose consumption and succinate production were significantly reduced by extracellular succinate in an engineered strain, S003. To understand the mechanism underlying the inhibition by succinate, comparative transcriptome analysis was performed. Among the downregulated genes, overexpression of the NCgl0275 gene was found to suppress the inhibition of glucose consumption and succinate production, resulting in a 37.7% increase in succinate production up to 55.4g/L in fed-batch fermentation. Further improvement was achieved by increasing the metabolic flux from PEP to OAA. The final engineered strain was able to produce 152.2g/L succinate, the highest production reported to date, with a yield of 1.1g/g glucose under anaerobic condition. These results suggest that the release of end-product inhibition coupled with an increase in key metabolic flux is a promising strategy for enhancing production of succinate. Copyright © 2017. Published by Elsevier Inc.

Physico-chemical parameter for production of lactic acid or ethanol of (corynebacterium glutamicum) bacteria

International Nuclear Information System (INIS)

Castellanos, Angelica; Garcia, Lina Marcela; Astudillo, Myriam; Lopez Galan, Jorge Enrique; Florez Pardo, Luz Marina.

2011-01-01

The interest to obtain products for the bio-fuel industry from renewable resources has directed research to find resistant and costs-effective biotechnological systems. Corynebacterium glutamicum, is a microorganism used to produce amino acids, that grows in wide variety of substrates and its resistance during fermentation to pH, temperature, osmotic pressure variations and alcohol aggregate, renders this organism a suitable candidate to improve by genetic modifications lactic acid and ethanol synthesis. However, some aspects of its physiology remain unknown, such us increase lactic acid and ethanol production from C5 and C6 sugars. For this reason, the main aim in our work was to identify the most important variables with impact on culture and the best culture conditions to produce lactic acid or ethanol in batch culture. To achieve this objective, eight variables were tested in culture using a statistical model. The best culture conditions were obtained and tested in a bacth bioreactor system. Temperature, biotin and glucose concentration were the variables with most impact (p - 1 , 16 g/l of lactic acid was obtained after 15 h of culture with an efficiency of 32%. High glucose consumption was observed during bacterial growth, which leads to low concentration of substrate for the production process; this suggests a culture feeding at the end of exponential growth phase, which can increase the production yield.

Isolation of Corynebacterium Xerosis from Jordanian Soil and a Study on its Antimicrobial Activity against a Range of Bacteria and Fungi

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El-Banna, Nasser

2004-01-01

A bacterial strain which has been identified as Corneybacterium Xerosis NB-2 was isolated from a soil sample from Jerash Private University, Jerash, Jordan. This isolate was found to produce an antimicrobial substance active only against filamentous fungi and yeasts (Aspergillus niger SQ 40, Fusarium oxysporium SQ11, Verticillium dahliae SQ 42, Saccharomyces SQ 46 and Candida albicans SQ 47). However, all tested gram-positive bacteria and gram negative bacteria (Bacillus megaterium SQ5, Bacillus cereus SQ6, Staphylococcus aureus SQ9, Streptococcus pyogens SQ10, Eschericshia coli SQ 22, Klepsiella spp SQ33 and SQ33 and Pseudonomas mallei SQ 34) were found to be resistant. In batch culture, the isolated NB-2 produced the antimicrobial substance late in the growth phase and antimicrobial activity of Corynebacterium Xerosis against filamentous fungi and yeasts which was not previously described. (author)

Effectiveness of Standard UV Depuration at Inactivating Cryptosporidium parvum Recovered from Spiked Pacific Oysters (Crassostrea gigas)▿

Science.gov (United States)

Sunnotel, O.; Snelling, W. J.; McDonough, N.; Browne, L.; Moore, J. E.; Dooley, J. S. G.; Lowery, C. J.

2007-01-01

When filter-feeding shellfish are consumed raw, because of their ability to concentrate and store waterborne pathogens, they are being increasingly associated with human gastroenteritis and have become recognized as important pathogen vectors. In the shellfish industry, UV depuration procedures are mandatory to reduce pathogen levels prior to human consumption. However, these guidelines are based around more susceptible fecal coliforms and Salmonella spp. and do not consider Cryptosporidium spp., which have significant resistance to environmental stresses. Thus, there is an urgent need to evaluate the efficiency of standard UV depuration against the survival of Cryptosporidium recovered from shellfish. Our study found that in industrial-scale shellfish depuration treatment tanks, standard UV treatment resulted in a 13-fold inactivation of recovered, viable C. parvum oocysts from spiked (1 × 106 oocysts liter −1) Pacific oysters. Depuration at half power also significantly reduced (P oysters. While UV treatment resulted in significant reductions of recovered viable oocysts, low numbers of viable oocysts were still recovered from oysters after depuration, making their consumption when raw a public health risk. Our study highlights the need for increased periodic monitoring programs for shellfish harvesting sites, improved depuration procedures, and revised microbial quality control parameters, including Cryptosporidium assessment, to minimize the risk of cryptosporidiosis. PMID:17574996

Development of Biotin-Prototrophic and -Hyperauxotrophic Corynebacterium glutamicum Strains

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Miyamoto, Aya; Mutoh, Sumire; Kitano, Yuko; Tajima, Mei; Shirakura, Daisuke; Takasaki, Manami; Mitsuhashi, Satoshi; Takeno, Seiki

2013-01-01

To develop the infrastructure for biotin production through naturally biotin-auxotrophic Corynebacterium glutamicum, we attempted to engineer the organism into a biotin prototroph and a biotin hyperauxotroph. To confer biotin prototrophy on the organism, the cotranscribed bioBF genes of Escherichia coli were introduced into the C. glutamicum genome, which originally lacked the bioF gene. The resulting strain still required biotin for growth, but it could be replaced by exogenous pimelic acid, a source of the biotin precursor pimelate thioester linked to either coenzyme A (CoA) or acyl carrier protein (ACP). To bridge the gap between the pimelate thioester and its dedicated precursor acyl-CoA (or -ACP), the bioI gene of Bacillus subtilis, which encoded a P450 protein that cleaves a carbon-carbon bond of an acyl-ACP to generate pimeloyl-ACP, was further expressed in the engineered strain by using a plasmid system. This resulted in a biotin prototroph that is capable of the de novo synthesis of biotin. On the other hand, the bioY gene responsible for biotin uptake was disrupted in wild-type C. glutamicum. Whereas the wild-type strain required approximately 1 μg of biotin per liter for normal growth, the bioY disruptant (ΔbioY) required approximately 1 mg of biotin per liter, almost 3 orders of magnitude higher than the wild-type level. The ΔbioY strain showed a similar high requirement for the precursor dethiobiotin, a substrate for bioB-encoded biotin synthase. To eliminate the dependency on dethiobiotin, the bioB gene was further disrupted in both the wild-type strain and the ΔbioY strain. By selectively using the resulting two strains (ΔbioB and ΔbioBY) as indicator strains, we developed a practical biotin bioassay system that can quantify biotin in the seven-digit range, from approximately 0.1 μg to 1 g per liter. This bioassay proved that the engineered biotin prototroph of C. glutamicum produced biotin directly from glucose, albeit at a marginally

Development of biotin-prototrophic and -hyperauxotrophic Corynebacterium glutamicum strains.

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Ikeda, Masato; Miyamoto, Aya; Mutoh, Sumire; Kitano, Yuko; Tajima, Mei; Shirakura, Daisuke; Takasaki, Manami; Mitsuhashi, Satoshi; Takeno, Seiki

2013-08-01

To develop the infrastructure for biotin production through naturally biotin-auxotrophic Corynebacterium glutamicum, we attempted to engineer the organism into a biotin prototroph and a biotin hyperauxotroph. To confer biotin prototrophy on the organism, the cotranscribed bioBF genes of Escherichia coli were introduced into the C. glutamicum genome, which originally lacked the bioF gene. The resulting strain still required biotin for growth, but it could be replaced by exogenous pimelic acid, a source of the biotin precursor pimelate thioester linked to either coenzyme A (CoA) or acyl carrier protein (ACP). To bridge the gap between the pimelate thioester and its dedicated precursor acyl-CoA (or -ACP), the bioI gene of Bacillus subtilis, which encoded a P450 protein that cleaves a carbon-carbon bond of an acyl-ACP to generate pimeloyl-ACP, was further expressed in the engineered strain by using a plasmid system. This resulted in a biotin prototroph that is capable of the de novo synthesis of biotin. On the other hand, the bioY gene responsible for biotin uptake was disrupted in wild-type C. glutamicum. Whereas the wild-type strain required approximately 1 μg of biotin per liter for normal growth, the bioY disruptant (ΔbioY) required approximately 1 mg of biotin per liter, almost 3 orders of magnitude higher than the wild-type level. The ΔbioY strain showed a similar high requirement for the precursor dethiobiotin, a substrate for bioB-encoded biotin synthase. To eliminate the dependency on dethiobiotin, the bioB gene was further disrupted in both the wild-type strain and the ΔbioY strain. By selectively using the resulting two strains (ΔbioB and ΔbioBY) as indicator strains, we developed a practical biotin bioassay system that can quantify biotin in the seven-digit range, from approximately 0.1 μg to 1 g per liter. This bioassay proved that the engineered biotin prototroph of C. glutamicum produced biotin directly from glucose, albeit at a marginally

Spatiotemporal associations of reservoir nutrient characteristics and the invasive, harmful alga Prymnesium parvum in West Texas

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VanLandeghem, Matthew M.; Farooqi, Mukhtar; Southard, Greg M.; Patino, Reynaldo

2015-01-01

Golden alga (Prymnesium parvum) is a harmful alga that has caused ecological and economic harm in freshwater and marine systems worldwide. In inland systems of North America, toxic blooms have nearly eliminated fish populations in some systems. Modifying nutrient profiles through alterations to land or water use may be a viable alternative for golden alga control in reservoirs. The main objective of this study was to improve our understanding of the nutrient dynamics that influence golden alga bloom formation and toxicity in west Texas reservoirs. We examined eight sites in the Upper Colorado River basin, Texas: three impacted reservoirs that have experienced repeated golden alga blooms; two reference reservoirs where golden alga is present but nontoxic; and three confluence sites downstream of the impacted and reference sites. Total, inorganic, and organic nitrogen and phosphorus and their ratios were quantified monthly along with golden alga abundance and ichthyotoxicity between December 2010 and July 2011. Blooms persisted for several months at the impacted sites, which were characterized by high organic nitrogen and low inorganic nitrogen. At impacted sites, abundance was positively associated with inorganic phosphorus and bloom termination coincided with increases in inorganic nitrogen and decreases in inorganic phosphorus in late spring. Management of both inorganic and organic forms of nutrients may create conditions in reservoirs unfavorable to golden alga.

Development of a CRISPR/Cas9 genome editing toolbox for Corynebacterium glutamicum.

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Liu, Jiao; Wang, Yu; Lu, Yujiao; Zheng, Ping; Sun, Jibin; Ma, Yanhe

2017-11-16

Corynebacterium glutamicum is an important industrial workhorse and advanced genetic engineering tools are urgently demanded. Recently, the clustered regularly interspaced short palindromic repeats (CRISPR) and their CRISPR-associated proteins (Cas) have revolutionized the field of genome engineering. The CRISPR/Cas9 system that utilizes NGG as protospacer adjacent motif (PAM) and has good targeting specificity can be developed into a powerful tool for efficient and precise genome editing of C. glutamicum. Herein, we developed a versatile CRISPR/Cas9 genome editing toolbox for C. glutamicum. Cas9 and gRNA expression cassettes were reconstituted to combat Cas9 toxicity and facilitate effective termination of gRNA transcription. Co-transformation of Cas9 and gRNA expression plasmids was exploited to overcome high-frequency mutation of cas9, allowing not only highly efficient gene deletion and insertion with plasmid-borne editing templates (efficiencies up to 60.0 and 62.5%, respectively) but also simple and time-saving operation. Furthermore, CRISPR/Cas9-mediated ssDNA recombineering was developed to precisely introduce small modifications and single-nucleotide changes into the genome of C. glutamicum with efficiencies over 80.0%. Notably, double-locus editing was also achieved in C. glutamicum. This toolbox works well in several C. glutamicum strains including the widely-used strains ATCC 13032 and ATCC 13869. In this study, we developed a CRISPR/Cas9 toolbox that could facilitate markerless gene deletion, gene insertion, precise base editing, and double-locus editing in C. glutamicum. The CRISPR/Cas9 toolbox holds promise for accelerating the engineering of C. glutamicum and advancing its application in the production of biochemicals and biofuels.

Comprehensive update of dalbavancin activity when tested against uncommonly isolated streptococci, Corynebacterium spp., Listeria monocytogenes, and Micrococcus spp. (1357 strains).

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Jones, Ronald N; Stilwell, Matthew G

2013-06-01

Dalbavancin is an investigational lipoglycopeptide having an extended serum elimination half-life allowing once-weekly dosing. Data from testing 1357 strains of uncommonly isolated species expand the dalbavancin spectrum details as follows (MIC50/90): β-haemolytic streptococcal serogroups C, F, and G (≤0.03/≤0.03 μg/mL), 7 viridans group of streptococci (≤0.03/≤0.03-0.06 μg/mL), 5 Corynebacterium spp. (0.06/0.12 μg/mL), Listeria monocytogenes (0.06/0.12 μg/mL), and Micrococcus spp. (≤0.03/≤0.03 μg/mL). Among all reported isolates, 99.8% of tested strains were inhibited at dalbavancin MIC values at ≤0.12 μg/mL. Dalbavancin remains very potent against rarer Gram-positive pathogens, using in vitro test experience with organisms cultured through 2011. Copyright © 2013 Elsevier Inc. All rights reserved.

Biotin protein ligase from Corynebacterium glutamicum: role for growth and L: -lysine production.

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Peters-Wendisch, P; Stansen, K C; Götker, S; Wendisch, V F

2012-03-01

Corynebacterium glutamicum is a biotin auxotrophic Gram-positive bacterium that is used for large-scale production of amino acids, especially of L-glutamate and L-lysine. It is known that biotin limitation triggers L-glutamate production and that L-lysine production can be increased by enhancing the activity of pyruvate carboxylase, one of two biotin-dependent proteins of C. glutamicum. The gene cg0814 (accession number YP_225000) has been annotated to code for putative biotin protein ligase BirA, but the protein has not yet been characterized. A discontinuous enzyme assay of biotin protein ligase activity was established using a 105aa peptide corresponding to the carboxyterminus of the biotin carboxylase/biotin carboxyl carrier protein subunit AccBC of the acetyl CoA carboxylase from C. glutamicum as acceptor substrate. Biotinylation of this biotin acceptor peptide was revealed with crude extracts of a strain overexpressing the birA gene and was shown to be ATP dependent. Thus, birA from C. glutamicum codes for a functional biotin protein ligase (EC 6.3.4.15). The gene birA from C. glutamicum was overexpressed and the transcriptome was compared with the control strain revealing no significant gene expression changes of the bio-genes. However, biotin protein ligase overproduction increased the level of the biotin-containing protein pyruvate carboxylase and entailed a significant growth advantage in glucose minimal medium. Moreover, birA overexpression resulted in a twofold higher L-lysine yield on glucose as compared with the control strain.

Identification of membrane-associated proteins with pathogenic potential expressed by Corynebacterium pseudotuberculosis grown in animal serum.

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Raynal, José Tadeu; Bastos, Bruno Lopes; Vilas-Boas, Priscilla Carolinne Bagano; Sousa, Thiago de Jesus; Costa-Silva, Marcos; de Sá, Maria da Conceição Aquino; Portela, Ricardo Wagner; Moura-Costa, Lília Ferreira; Azevedo, Vasco; Meyer, Roberto

2018-01-25

Previous works defining antigens that might be used as vaccine targets against Corynebacterium pseudotuberculosis, which is the causative agent of sheep and goat caseous lymphadenitis, have focused on secreted proteins produced in a chemically defined culture media. Considering that such antigens might not reflect the repertoire of proteins expressed during infection conditions, this experiment aimed to investigate the membrane-associated proteins with pathogenic potential expressed by C. pseudotuberculosis grown directly in animal serum. Its membrane-associated proteins have been extracted using an organic solvent enrichment methodology, followed by LC-MS/MS and bioinformatics analysis for protein identification and classification. The results revealed 22 membrane-associated proteins characterized as potentially pathogenic. An interaction network analysis indicated that the four potentially pathogenic proteins ciuA, fagA, OppA4 and OppCD were biologically connected within two distinct network pathways, which were both associated with the ABC Transporters KEGG pathway. These results suggest that C. pseudotuberculosis pathogenesis might be associated with the transport and uptake of nutrients; other seven identified potentially pathogenic membrane proteins also suggest that pathogenesis might involve events of bacterial resistance and adhesion. The proteins herein reported potentially reflect part of the protein repertoire expressed during real infection conditions and might be tested as vaccine antigens.

Disruption of pknG enhances production of gamma-aminobutyric acid by Corynebacterium glutamicum expressing glutamate decarboxylase.

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Okai, Naoko; Takahashi, Chihiro; Hatada, Kazuki; Ogino, Chiaki; Kondo, Akihiko

2014-01-01

Gamma-aminobutyric acid (GABA), a building block of the biodegradable plastic polyamide 4, is synthesized from glucose by Corynebacterium glutamicum that expresses Escherichia coli glutamate decarboxylase (GAD) B encoded by gadB. This strain was engineered to produce GABA more efficiently from biomass-derived sugars. To enhance GABA production further by increasing the intracellular concentration of its precursor glutamate, we focused on engineering pknG (encoding serine/threonine protein kinase G), which controls the activity of 2-oxoglutarate dehydrogenase (Odh) in the tricarboxylic acid cycle branch point leading to glutamate synthesis. We succeeded in expressing GadB in a C. glutamicum strain harboring a deletion of pknG. C. glutamicum strains GAD and GAD ∆pknG were cultured in GP2 medium containing 100 g L(-1) glucose and 0.1 mM pyridoxal 5'-phosphate. Strain GAD∆pknG produced 31.1 ± 0.41 g L(-1) (0.259 g L(-1) h(-1)) of GABA in 120 hours, representing a 2.29-fold higher level compared with GAD. The production yield of GABA from glucose by GAD∆pknG reached 0.893 mol mol(-1).

Mastitis in dairy cattle caused by Corynebacterium pseudotuberculosis and the feasibility of transmission by houseflies. I.

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Yeruham, I; Braverman, Y; Shpigel, N Y; Chizov-Ginzburg, A; Saran, A; Winkler, M

1996-09-01

Morbidity due to Corynebacterium pseudotuberculosis infection occurred in 29 dairy herds. The disease appeared basically in three clinical forms: cutaneous, mastitic, and visceral. The appearance of the disease showed a marked seasonality: in 23 herds it occurred during the spring and summer months (dry season) (March-October). The mastitic form occurred in only 10 herds and the causative bacterium was isolated from 33 cows (5.8%). All the strains of C. pseudotuberculosis isolated from the milk samples were found not to be nitrate reducers. The bacterium was excreted in the milk of six cows from herd B during a period of 11 months. In the mastitic cows, a decrease in milk production and considerable increases in the somatic cell count were noted. C. pseudotuberculosis was isolated from houseflies collected over a cow lesion. Laboratory-reared houseflies were successfully infected with C. pseudotuberculosis-contaminated milk, broth and sugar cubes. Flies infected with the bacterium from contaminated milk excreted the bacterium in their droppings for up to 4 h and from their saliva for up to 3 h post infection. The bacterium survived on the external organs of houseflies for no longer than 10 min post infection, after the flies had been dipped in contaminated broth.

Differences in the effects of host suppression on the adoptive immunotherapy of subcutaneous and visceral tumors

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Chang, A.E.; Shu, S.Y.; Chou, T.; Lafreniere, R.; Rosenberg, S.A.

1986-01-01

A syngeneic transplantable sarcoma induced in C57BL/6 mice, MCA 105, was used in studies to examine host suppression on the adoptive immunotherapy of established intradermal and experimentally induced pulmonary and hepatic metastases. Fresh immune splenocytes were generated from mice immunized to the MCA 105 tumor by a mixture of viable tumor cells and Corynebacterium parvum. The adoptive immunotherapy of intradermal MCA 105 tumor with immune cells required prior immunosuppression of the recipient by sublethal irradiation with 500 R or T-cell depletion. The effect of whole-body sublethal irradiation appeared to eliminate a systemic host suppression mechanism, since partialbody irradiation involving the tumor-bearing area did not permit successful immunotherapy. Host irradiation was not required to achieve successful immunotherapy of experimentally induced pulmonary or hepatic metastases. In nonirradiated recipients bearing both intradermal and pulmonary tumors, host suppression did not affect the function of transferred immune cells to induce regression of pulmonary metastases. Thus, suppression of adoptive immunotherapy appears to be relevant to tumors confined to the skin and subcutaneous tissue but not to tumor in visceral sites, such as the lung and liver

Transport of Cryptosporidium parvum Oocysts in Charge Heterogeneous Porous Media: Microfluidics Experiment and Numerical Simulation

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Liu, Y.; Meng, X.; Guo, Z.; Zhang, C.; Nguyen, T. H.; Hu, D.; Ji, J.; Yang, X.

2017-12-01

Colloidal attachment on charge heterogeneous grains has significant environmental implications for transport of hazardous colloids, such as pathogens, in the aquifer, where iron, manganese, and aluminium oxide minerals are the major source of surface charge heterogeneity of the aquifer grains. A patchwise surface charge model is often used to describe the surface charge heterogeneity of the grains. In the patchwise model, the colloidal attachment efficiency is linearly correlated with the fraction of the favorable patches (θ=λ(θf - θu)+θu). However, our previous microfluidic study showed that the attachment efficiency of oocysts of Cryptosporidium parvum, a waterborne protozoan parasite, was not linear correlated with the fraction of the favorable patches (λ). In this study, we developed a pore scale model to simulate colloidal transport and attachment on charge heterogeneous grains. The flow field was simulated using the LBM method and colloidal transport and attachment were simulated using the Lagrange particle tracking method. The pore scale model was calibrated with experimental results of colloidal and oocyst transport in microfluidic devices and was then used to simulate oocyst transport in charge heterogeneous porous media under a variety of environmental relative conditions, i.e. the fraction of favorable patchwise, ionic strength, and pH. The results of the pore scale simulations were used to evaluate the effect of surface charge heterogeneity on upscaling of oocyst transport from pore to continuum scale and to develop an applicable correlation between colloidal attachment efficiency and the fraction of the favorable patches.

Novel Polyoxyethylene-Containing Glycolipids Are Synthesized in Corynebacterium matruchotii and Mycobacterium smegmatis Cultured in the Presence of Tween 80

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Cindy Wang

2011-01-01

Full Text Available The addition of polyoxyethylene sorbitan monooleate (Tween 80 to a culture of mycobacteria greatly influences cell permeability and sensitivity to antibiotics but very little is known regarding the underlying mechanism. Here we show that Corynebacterium matruchotii (surrogate of mycobacteria converts Tween 80 to a structural series of polyoxyethylenic acids which are then used to form novel series-2A and series-2B glycolipids. Minor series-3 glycolipids were also synthesized. The polyoxyethylenic acids replaced corynomycolic acids in the cell wall. Correspondingly the trehalose dicorynomycolate content was reduced. MALDI mass spectrometry, MS-MS, 1H-NMR, and 13C-NMR were used to characterize the series-2 glycolipids. Series-2A glycolipid is trehalose 6-C36:2-corynomycolate-6′-polyoxyethylenate and series-2B glycolipid is trehalose 6-C36:2-corynomycolate-6′-furan ring-containing polyoxyethylenate. Mycobacterium smegmatis grown in the presence of Tween 80 also synthesizes series-2 type glycolipids. The synthesis of these novel glycolipids in corynebacteria and mycobacteria should result in gross changes in the cell wall permeability and drug sensitivity.

Comparative genome analysis of 19 Ureaplasma urealyticum and Ureaplasma parvum strains.

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Paralanov, Vanya; Lu, Jin; Duffy, Lynn B; Crabb, Donna M; Shrivastava, Susmita; Methé, Barbara A; Inman, Jason; Yooseph, Shibu; Xiao, Li; Cassell, Gail H; Waites, Ken B; Glass, John I

2012-05-30

Ureaplasma urealyticum (UUR) and Ureaplasma parvum (UPA) are sexually transmitted bacteria among humans implicated in a variety of disease states including but not limited to: nongonococcal urethritis, infertility, adverse pregnancy outcomes, chorioamnionitis, and bronchopulmonary dysplasia in neonates. There are 10 distinct serotypes of UUR and 4 of UPA. Efforts to determine whether difference in pathogenic potential exists at the ureaplasma serovar level have been hampered by limitations of antibody-based typing methods, multiple cross-reactions and poor discriminating capacity in clinical samples containing two or more serovars. We determined the genome sequences of the American Type Culture Collection (ATCC) type strains of all UUR and UPA serovars as well as four clinical isolates of UUR for which we were not able to determine serovar designation. UPA serovars had 0.75-0.78 Mbp genomes and UUR serovars were 0.84-0.95 Mbp. The original classification of ureaplasma isolates into distinct serovars was largely based on differences in the major ureaplasma surface antigen called the multiple banded antigen (MBA) and reactions of human and animal sera to the organisms. Whole genome analysis of the 14 serovars and the 4 clinical isolates showed the mba gene was part of a large superfamily, which is a phase variable gene system, and that some serovars have identical sets of mba genes. Most of the differences among serovars are hypothetical genes, and in general the two species and 14 serovars are extremely similar at the genome level. Comparative genome analysis suggests UUR is more capable of acquiring genes horizontally, which may contribute to its greater virulence for some conditions. The overwhelming evidence of extensive horizontal gene transfer among these organisms from our previous studies combined with our comparative analysis indicates that ureaplasmas exist as quasi-species rather than as stable serovars in their native environment. Therefore, differential

L-Serine overproduction with minimization of by-product synthesis by engineered Corynebacterium glutamicum.

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Zhu, Qinjian; Zhang, Xiaomei; Luo, Yuchang; Guo, Wen; Xu, Guoqiang; Shi, Jinsong; Xu, Zhenghong

2015-02-01

The direct fermentative production of L-serine by Corynebacterium glutamicum from sugars is attractive. However, superfluous by-product accumulation and low L-serine productivity limit its industrial production on large scale. This study aimed to investigate metabolic and bioprocess engineering strategies towards eliminating by-products as well as increasing L-serine productivity. Deletion of alaT and avtA encoding the transaminases and introduction of an attenuated mutant of acetohydroxyacid synthase (AHAS) increased both L-serine production level (26.23 g/L) and its productivity (0.27 g/L/h). Compared to the parent strain, the by-products L-alanine and L-valine accumulation in the resulting strain were reduced by 87 % (from 9.80 to 1.23 g/L) and 60 % (from 6.54 to 2.63 g/L), respectively. The modification decreased the metabolic flow towards the branched-chain amino acids (BCAAs) and induced to shift it towards L-serine production. Meanwhile, it was found that corn steep liquor (CSL) could stimulate cell growth and increase sucrose consumption rate as well as L-serine productivity. With addition of 2 g/L CSL, the resulting strain showed a significant improvement in the sucrose consumption rate (72 %) and the L-serine productivity (67 %). In fed-batch fermentation, 42.62 g/L of L-serine accumulation was achieved with a productivity of 0.44 g/L/h and yield of 0.21 g/g sucrose, which was the highest production of L-serine from sugars to date. The results demonstrated that combined metabolic and bioprocess engineering strategies could minimize by-product accumulation and improve L-serine productivity.

Metabolic evolution and a comparative omics analysis of Corynebacterium glutamicum for putrescine production.

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Li, Zhen; Shen, Yu-Ping; Jiang, Xuan-Long; Feng, Li-Shen; Liu, Jian-Zhong

2018-02-01

Putrescine is widely used in the industrial production of bioplastics, pharmaceuticals, agrochemicals, and surfactants. Because the highest titer of putrescine is much lower than that of its precursor L-ornithine reported in microorganisms to date, further work is needed to increase putrescine production in Corynebacterium glutamicum. We first compared 7 ornithine decarboxylase genes and found that the Enterobacter cloacae ornithine decarboxylase gene speC1 was most suitable for putrescine production in C. glutamicum. Increasing NADPH availability and blocking putrescine oxidation and acetylation were chosen as targets for metabolic engineering. The putrescine producer C. glutamicum PUT4 was first constructed by deleting puo, butA and snaA genes, and replacing the fabG gene with E. cloacae speC1. After adaptive evolution with C. glutamicum PUT4, the evolved strain C. glutamicum PUT-ALE, which produced an 96% higher amount of putrescine compared to the parent strain, was obtained. The whole genome resequencing indicates that the SNPs located in the odhA coding region may be associated with putrescine production. The comparative proteomic analysis reveals that the pentose phosphate and anaplerotic pathway, the glyoxylate cycle, and the ornithine biosynthetic pathway were upregulated in the evolved strain C. glutamicum PUT-ALE. The aspartate family, aromatic, and branched chain amino acid and fatty acid biosynthetic pathways were also observed to be downregulated in C. glutamicum PUT-ALE. Reducing OdhA activity by replacing the odhA native start codon GTG with TTG and overexpression of cgmA or pyc458 further improved putrescine production. Repressing the carB, ilvH, ilvB and aroE expression via CRISPRi also increased putrescine production by 5, 9, 16 and 19%, respectively.

Different modes of diaminopimelate synthesis and their role in cell wall integrity: a study with Corynebacterium glutamicum.

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Wehrmann, A; Phillipp, B; Sahm, H; Eggeling, L

1998-06-01

In eubacteria, there are three slightly different pathways for the synthesis of m-diaminopimelate (m-DAP), which is one of the key linking units of peptidoglycan. Surprisingly, for unknown reasons, some bacteria use two of these pathways together. An example is Corynebacterium glutamicum, which uses both the succinylase and dehydrogenase pathways for m-DAP synthesis. In this study, we clone dapD and prove by enzyme experiments that this gene encodes the succinylase (M(r) = 24082), initiating the succinylase pathway of m-DAP synthesis. By using gene-directed mutation, dapD, as well as dapE encoding the desuccinylase, was inactivated, thereby forcing C. glutamicum to use only the dehydrogenase pathway of m-DAP synthesis. The mutants are unable to grow on organic nitrogen sources. When supplied with low ammonium concentrations but excess carbon, their morphology is radically altered and they are less resistant to mechanical stress than the wild type. Since the succinylase has a high affinity toward its substrate and uses glutamate as the nitrogen donor, while the dehydrogenase has a low affinity and incorporates ammonium directly, the m-DAP synthesis is another example of twin activities present in bacteria for access to important metabolites such as the well-known twin activities for the synthesis of glutamate or for the uptake of potassium.

Reprogramming One-Carbon Metabolic Pathways To Decouple l-Serine Catabolism from Cell Growth in Corynebacterium glutamicum.

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Zhang, Yun; Shang, Xiuling; Lai, Shujuan; Zhang, Yu; Hu, Qitiao; Chai, Xin; Wang, Bo; Liu, Shuwen; Wen, Tingyi

2018-02-16

l-Serine, the principal one-carbon source for DNA biosynthesis, is difficult for microorganisms to accumulate due to the coupling of l-serine catabolism and microbial growth. Here, we reprogrammed the one-carbon unit metabolic pathways in Corynebacterium glutamicum to decouple l-serine catabolism from cell growth. In silico model-based simulation showed a negative influence on glyA-encoding serine hydroxymethyltransferase flux with l-serine productivity. Attenuation of glyA transcription resulted in increased l-serine accumulation, and a decrease in purine pools, poor growth and longer cell shapes. The gcvTHP-encoded glycine cleavage (Gcv) system from Escherichia coli was introduced into C. glutamicum, allowing glycine-derived 13 CH 2 to be assimilated into intracellular purine synthesis, which resulted in an increased amount of one-carbon units. Gcv introduction not only restored cell viability and morphology but also increased l-serine accumulation. Moreover, comparative proteomic analysis indicated that abundance changes of the enzymes involved in one-carbon unit cycles might be responsible for maintaining one-carbon unit homeostasis. Reprogramming of the one-carbon metabolic pathways allowed cells to reach a comparable growth rate to accumulate 13.21 g/L l-serine by fed-batch fermentation in minimal medium. This novel strategy provides new insights into the regulation of cellular properties and essential metabolite accumulation by introducing an extrinsic pathway.

Polynucleotide Phosphorylase, RNase E/G, and YbeY Are Involved in the Maturation of 4.5S RNA in Corynebacterium glutamicum.

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Maeda, Tomoya; Tanaka, Yuya; Wachi, Masaaki; Inui, Masayuki

2017-03-01

Corynebacterium glutamicum has been applied for the industrial production of various metabolites, such as amino acids. To understand the biosynthesis of the membrane protein in this bacterium, we investigated the process of signal recognition particle (SRP) assembly. SRP is found in all three domains of life and plays an important role in the membrane insertion of proteins. SRP RNA is initially transcribed as precursor molecules; however, relatively little is known about its maturation. In C. glutamicum , SRP consists of the Ffh protein and 4.5S RNA lacking an Alu domain. In this study, we found that 3'-to-5' exoribonuclease, polynucleotide phosphorylase (PNPase), and two endo-type RNases, RNase E/G and YbeY, are involved in the 3' maturation of 4.5S RNA in C. glutamicum The mature form of 4.5S RNA was inefficiently formed in Δ rneG Δ pnp mutant cells, suggesting the existence of an alternative pathway for the 3' maturation of 4.5S RNA. Primer extension analysis also revealed that the 5' mature end of 4.5S RNA corresponds to that of the transcriptional start site. Immunoprecipitated Ffh protein contained immature 4.5S RNA in Δ pnp , Δ rneG , and Δ ybeY mutants, suggesting that 4.5S RNA precursors can interact with Ffh. These results imply that the maturation of 4.5S RNA can be performed in the 4.5S RNA-Ffh complex. IMPORTANCE Overproduction of a membrane protein, such as a transporter, is useful for engineering of strains of Corynebacterium glutamicum , which is a workhorse of amino acid production. To understand membrane protein biogenesis in this bacterium, we investigated the process of signal recognition particle (SRP) assembly. SRP contains the Ffh protein and SRP RNA and plays an important role in the membrane insertion of proteins. Although SRP RNA is highly conserved among the three domains of life, relatively little is known about its maturation. We show that PNPase, RNase E/G, and YbeY are involved in the 3' maturation of the SRP RNA (4.5S RNA) in

Technetium-99m labeling and fibronectin binding ability of Corynebacterium diphtheriae; Marcacao de Corynebacterium diphtheriae com Tecnecio-99m e avaliacao da capacidade de ligacao a fibronectina de plasma humano

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Souza, S.M.S.; Nagao, P.E.; Bernardo-Filho, M. [Universidade do Estado do Rio de Janeiro, RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes; Pereira, G.A.; Napoleao, F.; Andrade, A.F.B.; Hirata Junior, R.; Mattos-Guaraldi, A.L. [Universidade do Estado do Rio de Janeiro, RJ (Brazil). Faculdade de Ciencias Medicas

2004-04-15

The use of radionuclides has permitted advances in areas of clinical and scientific knowledge. Several molecules and cells have been labelled with Technetium-99m ({sup 99m}Tc). The stannous chloride (SnCl{sub 2}) has a significant influence on the labeling and stability of {sup 99m}Tc radiotracers. The frequent risk of diphtheria epidemics has intensified interest in the virulence factors of Corynebacterium diphtheriae. Although studies have looked at potential adhesins including haemagglutinins and exposed sugar residues, the molecular basis of mechanisms of adherence remains unclear. Adherence of pathogens to mammalian tissues may be mediated by fibronectin (FN) found in body fluids, matrix of connective tissues, and cell surfaces. In the present study we evaluated the binding ability to human plasma FN by {sup 99m}Tc labeled-C.diphtheriae. Due to adverse effects of stannous ions, microorganisms were submitted to survival and filamentation induction assays. Data showed a dose dependent susceptibility to SnCl{sub 2} bactericidal effects. Cell filamentation was observed for concentrations of SnCl{sub 2} > 110 {mu}g/ml. Adherence levels of {sup 99m}Tc labelled 241strain to coverslips coated with 20 {mu}g/ml FN were higher (P = 0.0037) than coated with bovine serum albumin. FN binding by the sucrose fermenting 241 C. diphtheriae strain (8.9% + 2.6) was significantly lower (P=0.0139) than Staphylococcus aureus Cowan I strain (34.1% {+-} 1.2). Therefore, bacterial {sup 99m}Tc labeling represents an additional tool that may contribute to the comprehension of C. diphtheriae interactions with host receptors such as FN that act as biological organizers by holding bacterial cells in position and guiding their migration. (author)

Effect of tillage and rainfall on transport of manure-applied Cryptosporidium parvum oocysts through soil.

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Ramirez, Norma E; Wang, Ping; Lejeune, Jeff; Shipitalo, Martin J; Ward, Lucy A; Sreevatsan, Srinand; Dick, Warren A

2009-01-01

Most waterborne outbreaks of cryptosporidiosis have been attributed to agricultural sources due to the high prevalence of Cryptosporidium oocysts in animal wastes and manure spreading on farmlands. No-till, an effective conservation practice, often results in soil having higher water infiltration and percolation rates than conventional tillage. We treated six undisturbed no-till and six tilled soil blocks (30 by 30 by 30 cm) with 1 L liquid dairy manure containing 10(5) C. parvum oocysts per milliliter to test the effect of tillage and rainfall on oocyst transport. The blocks were subjected to rainfall treatments consisting of 5 mm or 30 mm in 30 min. Leachate was collected from the base of the blocks in 35-mL increments using a 64-cell grid lysimeter. Even before any rain was applied, approximately 300 mL of water from the liquid manure (30% of that applied) was transported through the no-till soil, but none through the tilled blocks. After rain was applied, a greater number and percentage of first leachate samples from the no-till soil blocks compared to the tilled blocks tested positive for Cryptosporidium oocysts. In contrast to leachate, greater numbers of oocysts were recovered from the tilled soil, itself, than from the no-till soil. Although tillage was the most important factor affecting oocyst transport, rainfall timing and intensity were also important. To minimize transport of Cryptosporidium in no-till fields, manure should be applied at least 48 h before heavy rainfall is anticipated or methods of disrupting the direct linkage of surface soil to drains, via macropores, need to be used.

MICROBIAL LANDSCAPE OF MICROFLORA OF A PHARYNX AT PATIENTS WITH TONSILLIT’S PATHOLOGY

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O. Yu. Borisova

2015-01-01

Full Text Available The microbial landscape of microflora of a pharynx at patients with tonsillit’s pathology were studied. Materials and methods. 79 patients from GBUZ “Research Institute of Clinical Otorhinolaryngology” (78.5% patients with various forms of chronic tonsillitis and 21.5% of patients without chronic tonsillitis (control group. Among patients of the main group with chronic tonsillitis, at 60 (96.8% patients there was a diagnosis chronic tonsillitis a toxical-allergic form of 1 degree (TAF I, at 1 (1.6% the patient — chronic tonsillitis a toxical-allergic form II of degree (TAF II and at 1 (1.6% the patient — chronic tonsillitis. Identification of microorganisms carried out on cultural-morphological and biochemical properties. Specific identification of the hardly cultivated microorganisms and Corynebacterium was carried out by MALDI-TOFF MS of BioMerieux VITEK MS MALDI-TOF (“bioMerieux”, France. Identification of the allocated Corynebacterium was carried out by amplification of a gene rpoB and the subsequent direct sequencing. Results. The majority (98.7% of the allocated microorganisms, treated 27 types and were Gram-positive. It is revealed 159 strains of 29 species of microorganisms, from them 41.4% of strains belonged to the Streptococcus, 19.7% — Staphylococcus, 36.9% — Corynebacterium. Among Streptococcus — 55.4% of S. viridans, 38.4% — S. pyogenes and 3.1% — of S. pneumoniae и S. oralis; Staphylococcus — 64.5% of S. aureus, 32.2% of S. epidermidis and 3.3% of S. hominis. 18 types of Corynebacterium — С. tuberculostearicum (17.2% strains, C. рseudodiphtheriticum (15.5% strains and C. aurimucosum (18.9% strains are revealed. At 44.3% of the surveyed patients the microflora is presented by a monoculture and at 55.7% associations are revealed. Conclusion. The microflora at patients with tonsillit’s pathology is characterized. At the expressed pathological process in a microbiota of a pharynx the monoculture while

Systems metabolic engineering of Corynebacterium glutamicum for production of the chemical chaperone ectoine.

Science.gov (United States)

Becker, Judith; Schäfer, Rudolf; Kohlstedt, Michael; Harder, Björn J; Borchert, Nicole S; Stöveken, Nadine; Bremer, Erhard; Wittmann, Christoph

2013-11-15

The stabilizing and function-preserving effects of ectoines have attracted considerable biotechnological interest up to industrial scale processes for their production. These rely on the release of ectoines from high-salinity-cultivated microbial producer cells upon an osmotic down-shock in rather complex processor configurations. There is growing interest in uncoupling the production of ectoines from the typical conditions required for their synthesis, and instead design strains that naturally release ectoines into the medium without the need for osmotic changes, since the use of high-salinity media in the fermentation process imposes notable constraints on the costs, design, and durability of fermenter systems. Here, we used a Corynebacterium glutamicum strain as a cellular chassis to establish a microbial cell factory for the biotechnological production of ectoines. The implementation of a mutant aspartokinase enzyme ensured efficient supply of L-aspartate-beta-semialdehyde, the precursor for ectoine biosynthesis. We further engineered the genome of the basic C. glutamicum strain by integrating a codon-optimized synthetic ectABCD gene cluster under expressional control of the strong and constitutive C. glutamicum tuf promoter. The resulting recombinant strain produced ectoine and excreted it into the medium; however, lysine was still found as a by-product. Subsequent inactivation of the L-lysine exporter prevented the undesired excretion of lysine while ectoine was still exported. Using the streamlined cell factory, a fed-batch process was established that allowed the production of ectoine with an overall productivity of 6.7 g L(-1) day(-1) under growth conditions that did not rely on the use of high-salinity media. The present study describes the construction of a stable microbial cell factory for recombinant production of ectoine. We successfully applied metabolic engineering strategies to optimize its synthetic production in the industrial workhorse C

Mutational analysis to identify the residues essential for the inhibition of N-acetyl glutamate kinase of Corynebacterium glutamicum.

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Huang, Yuanyuan; Zhang, Hao; Tian, Hongming; Li, Cheng; Han, Shuangyan; Lin, Ying; Zheng, Suiping

2015-09-01

N-acetyl glutamate kinase (NAGK) is a key enzyme in the synthesis of L-arginine that is inhibited by its end product L-arginine in Corynebacterium glutamicum (C. glutamicum). In this study, the potential binding sites of arginine and the residues essential for its inhibition were identified by homology modeling, inhibitor docking, and site-directed mutagenesis. The allosteric inhibition of NAGK was successfully alleviated by a mutation, as determined through analysis of mutant enzymes, which were overexpressed in vivo in C. glutamicum ATCC14067. Analysis of the mutant enzymes and docking analysis demonstrated that residue W23 positions an arginine molecule, and the interaction between arginine and residues L282, L283, and T284 may play an important role in the remote inhibitory process. Based on the results of the docking analysis of the effective mutants, we propose a linkage mechanism for the remote allosteric regulation of NAGK activity, in which residue R209 may play an essential role. In this study, the structure of the arginine-binding site of C. glutamicum NAGK (CgNAGK) was successfully predicted and the roles of the relevant residues were identified, providing new insight into the allosteric regulation of CgNAGK activity and a solid platform for the future construction of an optimized L-arginine producing strain.

Surveillance of a Ventilated Rack System for Corynebacterium bovis by Sampling Exhaust-Air Manifolds.

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Manuel, Christopher A; Pugazhenthi, Umarani; Leszczynski, Jori K

2016-01-01

Corynebacterium bovis causes an opportunistic infection of nude (Foxn1, nu/nu) mice, leading to nude mouse hyperkeratotic dermatitis (scaly skin disease). Enzootic in many nude mouse colonies, C. bovis spreads rapidly to naive nude mice, despite modern husbandry practices, and is very difficult to eradicate. To facilitate rapid detection in support of eradication efforts, we investigated a surveillance method based on quantitative real-time PCR (qPCR) evaluation of swabs collected from the horizontal exhaust manifold (HEM) of an IVC rack system. We first evaluated the efficacy of rack sanitation methods for removing C. bovis DNA from the HEM of racks housing endemic colonies of infected nude mice. Pressurized water used to flush the racks' air exhaust system followed by a standard rack-washer cycle was ineffective in eliminating C. bovis DNA. Only after autoclaving did all sanitized racks test negative for C. bovis DNA. We then measured the effects of stage of infection (early or established), cage density, and cage location on the rack on time-to-detection at the HEM. Stage of infection significantly affected time-to-detection, independent of cage location. Early infections required 7.3 ± 1.2 d whereas established infections required 1 ± 0 d for detection of C. bovis at the HEM. Cage density influenced the quantity of C. bovis DNA detected but not time-to-detection. The location of the cage on the rack affected the time-to-detection only during early C. bovis infections. We suggest that qPCR swabs of HEM are useful during the routine surveillance of nude mouse colonies for C. bovis infection.

Biosynthesis of rare ketoses through constructing a recombination pathway in an engineered Corynebacterium glutamicum.

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Yang, Jiangang; Zhu, Yueming; Li, Jitao; Men, Yan; Sun, Yuanxia; Ma, Yanhe

2015-01-01

Rare sugars have various known biological functions and potential for applications in pharmaceutical, cosmetics, and food industries. Here we designed and constructed a recombination pathway in Corynebacterium glutamicum, in which dihydroxyacetone phosphate (DHAP), an intermediate of the glycolytic pathway, and a variety of aldehydes were condensed to synthesize rare ketoses sequentially by rhamnulose-1-phosphate aldolase (RhaD) and fructose-1-phosphatase (YqaB) obtained from Escherichia coli. A wild-type strain harboring this artificial pathway had the ability to produce D-sorbose and D-psicose using D-glyceraldehyde and glucose as the substrates. The tpi gene, encoding triose phosphate isomerase was further deleted, and the concentration of DHAP increased to nearly 20-fold relative to that of the wild-type. After additional optimization of expression levels from rhaD and yqaB genes and of the fermentation conditions, the engineered strain SY6(pVRTY) exhibited preferable performance for rare ketoses production. Its yield increased to 0.59 mol/mol D-glyceraldehyde from 0.33 mol/mol D-glyceraldehyde and productivity to 2.35 g/L h from 0.58 g/L h. Moreover, this strain accumulated 19.5 g/L of D-sorbose and 13.4 g/L of D-psicose using a fed-batch culture mode under the optimal conditions. In addition, it was verified that the strain SY6(pVRTY) meanwhile had the ability to synthesize C4, C5, C6, and C7 rare ketoses when a range of representative achiral and homochiral aldehydes were applied as the substrates. Therefore, the platform strain exhibited the potential for microbial production of rare ketoses and deoxysugars. © 2014 Wiley Periodicals, Inc.

Molecular and phylogenetic characterization of Cryptosporidium and Giardia from pigs and cattle in Denmark

DEFF Research Database (Denmark)

Langkjær, Rikke Breinhold; Vigre, Håkan; Enemark, Heidi L.

2007-01-01

The genetic diversity of Cryptosporidium spp. and Giardia duodenalis from dairy cattle and pigs in Denmark was determined in the present study. Faecal samples from 1237 pigs and 1150 cattle originating from 50 sow herds and 50 dairy herds, respectively, were analysed for the presence of the two...... parasites by immunofluorescence microscopy. A large proportion of the (oo)cyst containing samples were selected for molecular characterization. Sequencing and phylogenetic analysis of the 18S rDNA locus and/or the HSP70 gene of 183 pig and 154 cattle isolates of Cryptosporidium revealed the presence of C....... suis, pig genotype II, C. parvum (cattle genotype), C. bovis, Cryptosporidium deer-like genotype and a novel C. suis-like genotype. For both cattle and pigs, a host age-related change in distribution of species/genotypes was observed. The zoonotic C. parvum (cattle genotype) was most prevalent in young...

An integrative in-silico approach for therapeutic target identification in the human pathogen Corynebacterium diphtheriae.

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Syed Babar Jamal

Full Text Available Corynebacterium diphtheriae (Cd is a Gram-positive human pathogen responsible for diphtheria infection and once regarded for high mortalities worldwide. The fatality gradually decreased with improved living standards and further alleviated when many immunization programs were introduced. However, numerous drug-resistant strains emerged recently that consequently decreased the efficacy of current therapeutics and vaccines, thereby obliging the scientific community to start investigating new therapeutic targets in pathogenic microorganisms. In this study, our contributions include the prediction of modelome of 13 C. diphtheriae strains, using the MHOLline workflow. A set of 463 conserved proteins were identified by combining the results of pangenomics based core-genome and core-modelome analyses. Further, using subtractive proteomics and modelomics approaches for target identification, a set of 23 proteins was selected as essential for the bacteria. Considering human as a host, eight of these proteins (glpX, nusB, rpsH, hisE, smpB, bioB, DIP1084, and DIP0983 were considered as essential and non-host homologs, and have been subjected to virtual screening using four different compound libraries (extracted from the ZINC database, plant-derived natural compounds and Di-terpenoid Iso-steviol derivatives. The proposed ligand molecules showed favorable interactions, lowered energy values and high complementarity with the predicted targets. Our proposed approach expedites the selection of C. diphtheriae putative proteins for broad-spectrum development of novel drugs and vaccines, owing to the fact that some of these targets have already been identified and validated in other organisms.

Implantation of Corynebacterium pseudodiphtheriticum for elimination of Staphylococcus aureus from the nasal cavity in volunteers

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Viacheslav, Ilyin; Kiryukhina, Nataliya

Nasal carriage of Staphylococcus aureus is a well-documented risk factor of infection and inflammation of the skin, soft tissues and bacteremia. It is also known that most often etiology of these disorders is associated with autoinfection. The present-day methods of opportunistic pathogens eradication from the nasal cavity are based principally on the use of antiseptic and antibacterial agents. For instance, a local antibiotic mupirocin in the form of nasal ointment is considered to be the gold standard for the treatment of S. aureus carriage. The literature describes investigations showing how mupirocin can strengthen antibiotic resistance in S. aureus strains, including those with methicillin resistance (MRSA). It is also common knowledge that recolonization of the nasal mucous membrane takes place within several months after mupirocin treatment. This circumstance dictates the necessity to look for alternative ways of preventing the S. aureus carriage and methods of elimination. One of the methods of nasal S. aureus elimination is implantation of nonpathogenic microorganisms which will extrude opportunistic pathogens without impinging the symbiotic microbiota. Effectiveness of saline suspension of Corynebacterium pseudodiphtheriticum containing spray was assessed in a several chamber experiments with simulation of some spaceflight factors (dry immersion, isolation). Various schemes of application of preparations were applied. In all cases of corynebacteria application the strong inhibiting effect against S. aureus was detected. This fact opens a prospect of using nonpathogenic corynebacteria as a nasal probiotic. Administration of the nasal corynebacteria spray possibly prevented cross-infection by MRSA and appearance of staphylococcal infection. Further pre-clinical and clinical study of this bacterial therapy method is under development.

Serum killing of Ureaplasma parvum shows serovar-determined susceptibility for normal individuals and common variable immuno-deficiency patients.

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Beeton, Michael L; Daha, Mohamed R; El-Shanawany, Tariq; Jolles, Stephen R; Kotecha, Sailesh; Spiller, O Brad

2012-02-01

Many Gram-negative bacteria, unlike Gram-positive, are directly lysed by complement. Ureaplasma can cause septic arthritis and meningitis in immunocompromised individuals and induce premature birth. Ureaplasma has no cell wall, cannot be Gram-stain classified and its serum susceptibility is unknown. Survival of Ureaplasma serovars (SV) 1, 3, 6 and 14 (collectively Ureaplasma parvum) were measured following incubation with normal or immunoglobulin-deficient patient serum (relative to heat-inactivated controls). Blocking monoclonal anti-C1q antibody and depletion of calcium, immunoglobulins, or lectins were used to determine the complement pathway responsible for killing. Eighty-three percent of normal sera killed SV1, 67% killed SV6 and 25% killed SV14; greater killing correlating to strong immunoblot identification of anti-Ureaplasma antibodies; killing was abrogated following ProteinA removal of IgG1. All normal sera killed SV3 in a C1q-dependent fashion, irrespective of immunoblot identification of anti-Ureaplasma antibodies; SV3 killing was unaffected by total IgG removal by ProteinG, where complement activity was retained. Only one of four common variable immunodeficient (CVID) patient sera failed to kill SV3, despite profound IgM and IgG deficiency for all; however, killing of SV3 and SV1 was restored with therapeutic intravenous immunoglobulin therapy. Only the classical complement pathway mediated Ureaplasma-cidal activity, sometimes in the absence of observable immunoblot reactive bands. Copyright © 2011 Elsevier GmbH. All rights reserved.

The uptake, distribution and translocation of 86Rb in alfalfa plants susceptible and resistant to the bacterial wilt and the effect of Corynebacterium insidiosum upon these processes

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Hanker, I.; Kudelova, A.

1981-01-01

Alfalfa (Medicago sativa L.) plants susceptible (S) and resistant (R) to bacterial wilt were fed via roots with a nutrient solution labelled with 86 Rb + , at different times after inoculation with Corynebacterium insidiosum (McCull.) H.L. Jens. The infection did not affect 86 Rb + uptake per plant in the course of a 14-day-period following inoculation; however, it affected its distribution differently in the S- and the R-plants. 86 Rb + uptake significantly decreased due to the infection in the S-plants on the day 49 after inoculation (a 4-h-exposure to 86 Rb + ), with the ions more slowly translocated to the shoots in diseased S-plants than in diseased R-plants. Likely factors causing these effects and their relationship to alfalfa resistance to bacterial wilt are discussed. (author)

Construction of in vitro transcription system for Corynebacterium glutamicum and its use in the recognition of promoters of different classes.

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Holátko, Jiří; Silar, Radoslav; Rabatinová, Alžbeta; Sanderová, Hana; Halada, Petr; Nešvera, Jan; Krásný, Libor; Pátek, Miroslav

2012-10-01

To facilitate transcription studies in Corynebacterium glutamicum, we have developed an in vitro transcription system for this bacterium used as an industrial producer of amino acids and a model organism for actinobacteria. This system consists of C. glutamicum RNA polymerase (RNAP) core (α2, β, β'), a sigma factor and a promoter-carrying DNA template, that is specifically recognized by the RNAP holoenzyme formed. The RNAP core was purified from the C. glutamicum strain with the modified rpoC gene, which produced His-tagged β' subunit. The C. glutamicum sigA and sigH genes were cloned and overexpressed using the Escherichia coli plasmid vector, and the sigma subunits σ(A) and σ(H) were purified by affinity chromatography. Using the reconstituted C. glutamicum holo-RNAPs, recognition of the σ(A)- and σ(H)-dependent promoters and synthesis of the specific transcripts was demonstrated. The developed in vitro transcription system is a novel tool that can be used to directly prove the specific recognition of a promoter by the particular σ factor(s) and to analyze transcriptional control by various regulatory proteins in C. glutamicum.

Protective immunity induced in mice by F8.1 and F8.2 antigens purified from Schistosoma mansoni eggs

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Claudia Campra Ferreira

1998-01-01

Full Text Available Schistosoma mansoni soluble egg antigens (SEA were fractionated by isoelectric focusing, resulting in 20 components, characterized by pH, absorbance and protein concentration. The higher absorbance fractions were submitted to electrophoresis, and fraction 8 (F8 presented a specific pattern of bands on its isoelectric point. Protein 3 was observed only on F8, and so, it was utilized to rabbit immunization, in order to evaluate its capacity of inducing protective immunity. IgG antibodies from rabbit anti-F8 serum were coupled to Sepharose, and used to obtain the specific antigen by affinity chromatography. This antigen, submitted to electrophoresis, presented two proteic bands (F8.1 and F8.2, which were transferred to nitrocellulose membrane (PVDF and sequenciated. The homology of F8.2 to known proteins was determined using the Basic Local Alignment Search Tool program (BLASTp. Significant homologies were obtained for the rabbit cytosolic Ca2+ uptake inhibitor, and for the bird a1-proteinase inhibitor. Immunization of mice with F8.1 and F8.2, in the presence of Corynebacterium parvum and Al(OH3 as adjuvant, induced a significant protection degree against challenge infection, as observed by the decrease on worm burden recovered from portal system.

Metabolic flux distributions in Corynebacterium glutamicum during growth and lysine overproduction. Reprinted from Biotechnology and Bioengineering, Vol. 41, Pp 633-646 (1993).

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Vallino, J J; Stephanopoulos, G

2000-03-20

The two main contributions of this article are the solidification of Corynebacterium glutamicum biochemistry guided by bioreaction network analysis, and the determination of basal metabolic flux distributions during growth and lysine synthesis. Employed methodology makes use of stoichiometrically based mass balances to determine flux distributions in the C. glutamicum metabolic network. Presented are a brief description of the methodology, a thorough literature review of glutamic acid bacteria biochemistry, and specific results obtained through a combination of fermentation studies and analysis-directed intracellular assays. The latter include the findings of the lack of activity of glyoxylate shunt, and that phosphoenolpyruvate carboxylase (PPC) is the only anaplerotic reaction expressed in C. glutamicum cultivated on glucose minimal media. Network simplifications afforded by the above findings facilitated the determination of metabolic flux distributions under a variety of culture conditions and led to the following conclusions. Both the pentose phosphate pathway and PPC support significant fluxes during growth and lysine overproduction, and that flux partitioning at the glucosa-6-phosphate branch point does not appear to limit lysine synthesis. Copyright 1993 John Wiley & Sons, Inc.

Complete genome sequence and lifestyle of black-pigmented Corynebacterium aurimucosum ATCC 700975 (formerly C. nigricans CN-1 isolated from a vaginal swab of a woman with spontaneous abortion

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Gartemann Karl-Heinz

2010-02-01

Full Text Available Abstract Background Corynebacterium aurimucosum is a slightly yellowish, non-lipophilic, facultative anaerobic member of the genus Corynebacterium and predominantly isolated from human clinical specimens. Unusual black-pigmented variants of C. aurimucosum (originally named as C. nigricans continue to be recovered from the female urogenital tract and they are associated with complications during pregnancy. C. aurimucosum ATCC 700975 (C. nigricans CN-1 was originally isolated from a vaginal swab of a 34-year-old woman who experienced a spontaneous abortion during month six of pregnancy. For a better understanding of the physiology and lifestyle of this potential urogenital pathogen, the complete genome sequence of C. aurimucosum ATCC 700975 was determined. Results Sequencing and assembly of the C. aurimucosum ATCC 700975 genome yielded a circular chromosome of 2,790,189 bp in size and the 29,037-bp plasmid pET44827. Specific gene sets associated with the central metabolism of C. aurimucosum apparently provide enhanced metabolic flexibility and adaptability in aerobic, anaerobic and low-pH environments, including gene clusters for the uptake and degradation of aromatic amines, L-histidine and L-tartrate as well as a gene region for the formation of selenocysteine and its incorporation into formate dehydrogenase. Plasmid pET44827 codes for a non-ribosomal peptide synthetase that plays the pivotal role in the synthesis of the characteristic black pigment of C. aurimucosum ATCC 700975. Conclusions The data obtained by the genome project suggest that C. aurimucosum could be both a resident of the human gut and possibly a pathogen in the female genital tract causing complications during pregnancy. Since hitherto all black-pigmented C. aurimucosum strains have been recovered from female genital source, biosynthesis of the pigment is apparently required for colonization by protecting the bacterial cells against the high hydrogen peroxide concentration in

Effects of phosphoenolpyruvate carboxylase desensitization on glutamic acid production in Corynebacterium glutamicum ATCC 13032.

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Wada, Masaru; Sawada, Kazunori; Ogura, Kotaro; Shimono, Yuta; Hagiwara, Takuya; Sugimoto, Masakazu; Onuki, Akiko; Yokota, Atsushi

2016-02-01

Phosphoenolpyruvate carboxylase (PEPC) in Corynebacterium glutamicum ATCC13032, a glutamic-acid producing actinobacterium, is subject to feedback inhibition by metabolic intermediates such as aspartic acid and 2-oxoglutaric acid, which implies the importance of PEPC in replenishing oxaloacetic acid into the TCA cycle. Here, we investigated the effects of feedback-insensitive PEPC on glutamic acid production. A single amino-acid substitution in PEPC, D299N, was found to relieve the feedback control by aspartic acid, but not by 2-oxoglutaric acid. A simple mutant, strain R1, having the D299N substitution in PEPC was constructed from ATCC 13032 using the double-crossover chromosome replacement technique. Strain R1 produced glutamic acid at a concentration of 31.0 g/L from 100 g/L glucose in a jar fermentor culture under biotin-limited conditions, which was significantly higher than that of the parent, 26.0 g/L (1.19-fold), indicative of the positive effect of desensitized PEPC on glutamic acid production. Another mutant, strain DR1, having both desensitized PEPC and PYK-gene deleted mutations, was constructed in a similar manner using strain D1 with a PYK-gene deleted mutation as the parent. This mutation had been shown to enhance glutamic acid production in our previous study. Although marginal, strain D1 produced higher glutamic acid, 28.8 g/L, than ATCC13032 (1.11-fold). In contrast, glutamic acid production by strain DR-1 was elevated up to 36.9 g/L, which was 1.42-fold higher than ATCC13032 and significantly higher than the other three strains. The results showed a synergistic effect of these two mutations on glutamic acid production in C. glutamicum. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Metabolic engineering of Corynebacterium glutamicum to produce GDP-L-fucose from glucose and mannose.

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Chin, Young-Wook; Park, Jin-Byung; Park, Yong-Cheol; Kim, Kyoung Heon; Seo, Jin-Ho

2013-06-01

Wild-type Corynebacterium glutamicum was metabolically engineered to convert glucose and mannose into guanosine 5'-diphosphate (GDP)-L-fucose, a precursor of fucosyl-oligosaccharides, which are involved in various biological and pathological functions. This was done by introducing the gmd and wcaG genes of Escherichia coli encoding GDP-D-mannose-4,6-dehydratase and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase, respectively, which are known as key enzymes in the production of GDP-L-fucose from GDP-D-mannose. Coexpression of the genes allowed the recombinant C. glutamicum cells to produce GDP-L-fucose in a minimal medium containing glucose and mannose as carbon sources. The specific product formation rate was much higher during growth on mannose than on glucose. In addition, the specific product formation rate was further increased by coexpressing the endogenous phosphomanno-mutase gene (manB) and GTP-mannose-1-phosphate guanylyl-transferase gene (manC), which are involved in the conversion of mannose-6-phosphate into GDP-D-mannose. However, the overexpression of manA encoding mannose-6-phosphate isomerase, catalyzing interconversion of mannose-6-phosphate and fructose-6-phosphate showed a negative effect on formation of the target product. Overall, coexpression of gmd, wcaG, manB and manC in C. glutamicum enabled production of GDP-L-fucose at the specific rate of 0.11 mg g cell(-1) h(-1). The specific GDP-L-fucose content reached 5.5 mg g cell(-1), which is a 2.4-fold higher than that of the recombinant E. coli overexpressing gmd, wcaG, manB and manC under comparable conditions. Well-established metabolic engineering tools may permit optimization of the carbon and cofactor metabolisms of C. glutamicum to further improve their production capacity.

An experimental analysis of harmful algae-zooplankton interactions and the ultimate defense

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Remmel, E.J.; Kohmescher, N.; Larson, J.H.; Hambright, K.D.

2011-01-01

We examined effects of the invasive, toxigenic haptophyte Prymnesium parvum on grazing rates, feeding behaviors, and life-history characteristics of clonal lineages of three daphniid zooplankton species. Grazing experiments revealed similar clearance rates for P. parvum and a common green alga. Behavioral observations revealed no significant effects of P. parvum on daphniid feeding behaviors after 30 min, but major declines in appendage beat rates after 1 h. Chronic exposure (10 d) to P. parvum resulted in severe reductions in daphniid growth rates, age at first reproduction, fecundity, and survivorship at densities as low as 7750 cells mL-1. Thus, in addition to direct fish mortality during P. parvum blooms of 50,000-200,000 cells mL-1, the entire food web of an invaded system may be subjected to potentially severe negative consequences even at nonbloom densities of P. parvum. ?? 2011, by the American Society of Limnology and Oceanography, Inc.

Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model

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Bartelt, Luther A.; Bolick, David T.; Kolling, Glynis L.; Zaenker, Edna I.; Lara, Ana M.; Noronha, Francisco Jose; Cowardin, Carrie A.; Moore, John H.; Turner, Jerrold R.; Warren, Cirle A.; Buck, Gregory A.; Guerrant, Richard L.

2016-01-01

Cryptosporidium is a major cause of severe diarrhea, especially in malnourished children. Using a murine model of C. parvum oocyst challenge that recapitulates clinical features of severe cryptosporidiosis during malnutrition, we interrogated the effect of protein malnutrition (PM) on primary and secondary responses to C. parvum challenge, and tested the differential ability of mucosal priming strategies to overcome the PM-induced susceptibility. We determined that while PM fundamentally alters systemic and mucosal primary immune responses to Cryptosporidium, priming with C. parvum (106 oocysts) provides robust protective immunity against re-challenge despite ongoing PM. C. parvum priming restores mucosal Th1-type effectors (CD3+CD8+CD103+ T-cells) and cytokines (IFNγ, and IL12p40) that otherwise decrease with ongoing PM. Vaccination strategies with Cryptosporidium antigens expressed in the S. Typhi vector 908htr, however, do not enhance Th1-type responses to C. parvum challenge during PM, even though vaccination strongly boosts immunity in challenged fully nourished hosts. Remote non-specific exposures to the attenuated S. Typhi vector alone or the TLR9 agonist CpG ODN-1668 can partially attenuate C. parvum severity during PM, but neither as effectively as viable C. parvum priming. We conclude that although PM interferes with basal and vaccine-boosted immune responses to C. parvum, sustained reductions in disease severity are possible through mucosal activators of host defenses, and specifically C. parvum priming can elicit impressively robust Th1-type protective immunity despite ongoing protein malnutrition. These findings add insight into potential correlates of Cryptosporidium immunity and future vaccine strategies in malnourished children. PMID:27467505

Promoter library-based module combination (PLMC) technology for optimization of threonine biosynthesis in Corynebacterium glutamicum.

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Wei, Liang; Xu, Ning; Wang, Yiran; Zhou, Wei; Han, Guoqiang; Ma, Yanhe; Liu, Jun

2018-05-01

Due to the lack of efficient control elements and tools, the fine-tuning of gene expression in the multi-gene metabolic pathways is still a great challenge for engineering microbial cell factories, especially for the important industrial microorganism Corynebacterium glutamicum. In this study, the promoter library-based module combination (PLMC) technology was developed to efficiently optimize the expression of genes in C. glutamicum. A random promoter library was designed to contain the putative - 10 (NNTANANT) and - 35 (NNGNCN) consensus motifs, and refined through a three-step screening procedure to achieve numerous genetic control elements with different strength levels, including fluorescence-activated cell sorting (FACS) screening, agar plate screening, and 96-well plate screening. Multiple conventional strategies were employed for further precise characterizations of the promoter library, such as real-time quantitative PCR, sodium dodecyl sulfate polyacrylamide gel electrophoresis, FACS analysis, and the lacZ reporter system. These results suggested that the established promoter elements effectively regulated gene expression and showed varying strengths over a wide range. Subsequently, a multi-module combination technology was created based on the efficient promoter elements for combination and optimization of modules in the multi-gene pathways. Using this technology, the threonine biosynthesis pathway was reconstructed and optimized by predictable tuning expression of five modules in C. glutamicum. The threonine titer of the optimized strain was significantly improved to 12.8 g/L, an approximate 6.1-fold higher than that of the control strain. Overall, the PLMC technology presented in this study provides a rapid and effective method for combination and optimization of multi-gene pathways in C. glutamicum.

Characterization and chromosomal organization of the murD-murC-ftsQ region of Corynebacterium glutamicum ATCC 13869.

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Ramos, Angelina; Honrubia, Maria P; Vega, Daniel; Ayala, Juan A; Bouhss, Ahmed; Mengin-Lecreulx, Dominique; Gil, José A

2004-04-01

The sequence of a 4.6-kb region of DNA from Corynebacterium glutamicum ATCC 13869 lying upstream from the ftsQ-ftsZ region has been determined. The region contains four genes with high similarity to the murD, ftsW, murG, and murC genes from different microorganisms. The products of these mur genes probably catalyse several steps in the formation of the precursors for peptidoglycan synthesis in C. glutamicum, whereas ftsW might play also a role in the stabilisation of the FtsZ ring during cell division. The murC gene product was purified to near homogeneity and its UDP-N-acetylmuramate: L-alanine adding activity was demonstrated. Northern analysis indicated that ftsW, murG and ftsQ are poorly expressed in C. glutamicum whereas murC and ftsZ are expressed at higher levels at the beginning of the exponential phase. Dicistronic (ftsQ-ftsZ) and monocistronic (murC and ftsZ) transcripts can be detected using specific probes and are in agreement with the lack of transcriptional terminators in the partially analysed dcw cluster. Disruption experiments performed in C. glutamicum using internal fragments of the ftsW, murG and murC genes allowed us to conclude that FtsW, MurG, and MurC are essential gene products in C. glutamicum.

Integrated Analysis of the Transcriptome and Metabolome of Corynebacterium glutamicum during Penicillin-Induced Glutamic Acid Production.

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Hirasawa, Takashi; Saito, Masaki; Yoshikawa, Katsunori; Furusawa, Chikara; Shmizu, Hiroshi

2018-05-01

Corynebacterium glutamicum is known for its ability to produce glutamic acid and has been utilized for the fermentative production of various amino acids. Glutamic acid production in C. glutamicum is induced by penicillin. In this study, the transcriptome and metabolome of C. glutamicum is analyzed to understand the mechanism of penicillin-induced glutamic acid production. Transcriptomic analysis with DNA microarray revealed that expression of some glycolysis- and TCA cycle-related genes, which include those encoding the enzymes involved in conversion of glucose to 2-oxoglutaric acid, is upregulated after penicillin addition. Meanwhile, expression of some TCA cycle-related genes, encoding the enzymes for conversion of 2-oxoglutaric acid to oxaloacetic acid, and the anaplerotic reactions decreased. In addition, expression of NCgl1221 and odhI, encoding proteins involved in glutamic acid excretion and inhibition of the 2-oxoglutarate dehydrogenase, respectively, is upregulated. Functional category enrichment analysis of genes upregulated and downregulated after penicillin addition revealed that genes for signal transduction systems are enriched among upregulated genes, whereas those for energy production and carbohydrate and amino acid metabolisms are enriched among the downregulated genes. As for the metabolomic analysis using capillary electrophoresis time-of-flight mass spectrometry, the intracellular content of most metabolites of the glycolysis and the TCA cycle decreased dramatically after penicillin addition. Overall, these results indicate that the cellular metabolism and glutamic acid excretion are mainly optimized at the transcription level during penicillin-induced glutamic acid production by C. glutamicum. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Selection and Characterization of a Lysine Yielding Mutant of Corynebacterium glutamicum - a Soil Isolate from Pakistan

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Habib-ur-Rehman§٭, Abdul Hameed and Safia Ahmed

2012-01-01

Full Text Available L-lysine is the second limiting amino acid for poultry and supplemented in broiler feed for optimal performance. Lysine can be produced by inducing mutation in glutamate producing bacteria. The study was conducted to enhance lysine production from a local strain of Corynebacterium glutamicum. The bacterium was mutated by exposure to UV. Mutants resistant to s-2-aminoethyle L-cystein (AEC and showing auxotrophy for L-homoserine were screened for lysine production qualitatively and quantitatively. A mutant showing highest production of lysine (8.2 mg/mL was selected for optimization of physical and nutritional parameters for maximum production of lysine in shake flask. An initial pH 7.6, 30˚C temperature, 300 rpm and 60 h incubation time were the optimized values of physical requirements. Cane molasses and corn starch hydrolysate were required at 15% (w/v in the fermentation media which provided around 9% total sugars to produce maximum lysine (17 to 18 mg/mL. When amonium sulphate was used at 3.5% (w/v level in molasses or corn starch hydrolysate based fermentation media, production of lysine slightly increased above 18 mg/mL. It is concluded that industrial by products like cane molasses, corn steep liquor, and corn starch hydrolysate can be used as carbon and organic nitrogen sources in fermentation medium for scale up process of lysine production and this lysine enriched broth may be used in broiler feed later. However, more potent lysine producing mutant and additional in vivo trials would be required to commercialize this product.

Distinct roles of two anaplerotic pathways in glutamate production induced by biotin limitation in Corynebacterium glutamicum.

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Sato, Hiroki; Orishimo, Keita; Shirai, Tomokazu; Hirasawa, Takashi; Nagahisa, Keisuke; Shimizu, Hiroshi; Wachi, Masaaki

2008-07-01

Corynebacterium glutamicum is a biotin auxotrophic bacterium in which glutamate production is induced under biotin-limited conditions. During glutamate production, anaplerotic reactions catalyzed by phosphoenolpyruvate carboxylase (PEPC) and a biotin-containing enzyme pyruvate carboxylase (PC) are believed to play an important role in supplying oxaloacetate in the tricarboxylic acid cycle. To understand the distinct roles of PEPC and PC on glutamate production by C. glutamicum, we observed glutamate production induced under biotin-limited conditions in the disruptants of the genes encoding PEPC (ppc) and PC (pyc), respectively. The pyc disruptant retained the ability to produce high amounts of glutamate, and lactate was simultaneously produced probably due to the increased intracellular pyruvate levels. On the other hand, the ppc knockout mutant could not produce glutamate. Additionally, glutamate production in the pyc disruptant was enhanced by overexpression of ppc rather than disruption of the lactate dehydrogenase gene (ldh), which is involved in lactate production. Metabolic flux analysis based on the 13C-labeling experiment and measurement of 13C-enrichment in glutamate using nuclear magnetic resonance spectroscopy revealed that the flux for anaplerotic reactions in the pyc disruptant was lower than that in the wild type, concomitantly increasing the flux for lactate formation. Moreover, overexpression of ppc increased this flux in both the pyc disruptant and the wild type. Our results suggest that the PEPC-catalyzed anaplerotic reaction is necessary for glutamate production induced under biotin-limited conditions, because PC is not active during glutamate production, and overexpression of ppc effectively enhances glutamate production under biotin-limited conditions.

In vitro activities of the new semisynthetic glycopeptide telavancin (TD-6424), vancomycin, daptomycin, linezolid, and four comparator agents against anaerobic gram-positive species and Corynebacterium spp.

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Goldstein, Ellie J C; Citron, Diane M; Merriam, C Vreni; Warren, Yumi A; Tyrrell, Kerin L; Fernandez, Helen T

2004-06-01

Telavancin is a new semisynthetic glycopeptide anti-infective with multiple mechanisms of action, including inhibition of bacterial membrane phospholipid synthesis and inhibition of bacterial cell wall synthesis. We determined the in vitro activities of telavancin, vancomycin, daptomycin, linezolid, quinupristin-dalfopristin, imipenem, piperacillin-tazobactam, and ampicillin against 268 clinical isolates of anaerobic gram-positive organisms and 31 Corynebacterium strains using agar dilution methods according to National Committee for Clinical Laboratory Standards procedures. Plates with daptomycin were supplemented with Ca(2+) to 50 mg/liter. The MICs at which 90% of isolates tested were inhibited (MIC(90)s) for telavancin and vancomycin were as follows: Actinomyces spp. (n = 45), 0.25 and 1 microg/ml, respectively; Clostridium difficile (n = 14), 0.25 and 1 microg/ml, respectively; Clostridium ramosum (n = 16), 1 and 4 microg/ml, respectively; Clostridium innocuum (n = 15), 4 and 16 microg/ml, respectively; Clostridium clostridioforme (n = 15), 8 and 1 microg/ml, respectively; Eubacterium group (n = 33), 0.25 and 2 microg/ml, respectively; Lactobacillus spp. (n = 26), 0.5 and 4 microg/ml, respectively; Propionibacterium spp. (n = 34), 0.125 and 0.5 microg/ml, respectively; Peptostreptococcus spp. (n = 52), 0.125 and 0.5 microg/ml, respectively; and Corynebacterium spp. (n = 31), 0.03 and 0.5 microg/ml, respectively. The activity of TD-6424 was similar to that of quinupristin-dalfopristin for most strains except C. clostridioforme and Lactobacillus casei, where quinupristin-dalfopristin was three- to fivefold more active. Daptomycin had decreased activity (MIC > 4 microg/ml) against 14 strains of Actinomyces spp. and all C. ramosum, Eubacterium lentum, and Lactobacillus plantarum strains. Linezolid showed decreased activity (MIC > 4 microg/ml) against C. ramosum, two strains of C. difficile, and 15 strains of Lactobacillus spp. Imipenem and piperacillin

Fluorescent microspheres as surrogates in evaluating the efficacy of riverbank filtration for removing Cryptosporidium parvum oocysts and other pathogens

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Harvey, Ronald W.; Metge, David W.; Sheets, Rodney A.; Jasperse, Jay

2011-01-01

A major benefit of riverbank filtration (RBF) is that it provides a relatively effective means for pathogen removal. There is a need to conduct more injection-and-recovery transport studies at operating RBF sites in order to properly assess the combined effects of the site heterogeneities and ambient physicochemical conditions, which are difficult to replicate in the lab. For field transport studies involving pathogens, there is considerable interest in using fluorescent carboxylated microspheres (FCM) as surrogates, because they are chemically inert, negatively charged, easy to detect, available in a wide variety of sizes, and have been found to be nonhazardous in tracer applications. Although there have been a number of in-situ studies comparing the subsurface transport behaviors of FCM to those of bacteria and viruses, much less is known about their suitability for investigations of protozoa. Oocysts of the intestinal protozoan pathogen Cryptosporidium spp are of particular concern for many RBF operations because of their ubiquity and persistence in rivers and high resistance to chlorine disinfection. Although microspheres often have proven to be less-than-ideal analogs for capturing the abiotic transport behavior of viruses and bacteria, there is encouraging recent evidence regarding use of FCM as surrogates for C. parvum oocysts. This chapter discusses the potential of fluorescent microspheres as safe and easy-to-detect surrogates for evaluating the efficacy of RBF operations for removing pathogens, particularly Cryptosporidium, from source waters at different points along the flow path.

Vitek 2 ANC card versus BBL Crystal Anaerobe and RapID ANA II for identification of clinical anaerobic bacteria.

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Blairon, Laurent; Maza, Mengi L; Wybo, Ingrid; Piérard, Denis; Dediste, Anne; Vandenberg, Olivier

2010-08-01

The Vitek 2 Anaerobe and Corynebacterium Identification Card (ANC) was recently evaluated in a multicentre study. In the present work, this system was compared with the BBL Crystal Anaerobe and RapID ANA II panels. These kits were tested using 196 strains of anaerobes that had been previously identified by gas-liquid chromatography. Identification to the species or to the genus level was 75.0%, 81.1% and 70.9% for Crystal, RapID and Vitek, respectively. Vitek ANC failed to provide any identification in 20.4% of the strains, but it had fewer misidentifications than RapID. The confidence factors provided on the results report of each kit were not always correlated with a lower risk of major errors, with the exception of Vitek 2 in which a confidence factor higher than 0.86 excluded the risk of misidentification in more than 87% of isolates. The lower rate of identification by the Vitek and Crystal panels is mostly due the lower ability of these systems to identify the Clostridia. Overall, the three panels are comparable but need improvement to a better accuracy. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Development of an indirect ELISA to detect Corynebacterium pseudotuberculosis specific antibodies in sheep employing T1 strain culture supernatant as antigen

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Miriam F. Rebouças

2013-11-01

Full Text Available Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CLA, a chronic disease that affects goats and sheep, characterized by granuloma formation in subcutaneous and internal lymph nodes. CLA causes significant economic losses to commercial goat herds. In this study, we aimed to test secreted antigens secreted from T1 strain bacteria grown in brain heart infusion (BHI broth in an indirect ELISA system to determine the presence of specific immunoglobulins against C. pseudotuberculosis. We analyzed the BHI antigen electrophoretic profile and the recognition pattern by infected sheep sera samples. The ELISA results were compared with multiplex PCR assay and IFN-gamma production. The ELISA was able to discriminate between negative and positive animals, with a sensitivity of 89% and a specificity of 99%, using microbiological isolation as gold standard. When this assay was compared with multiplex PCR and specific IFN-gamma quantification, six discrepant results were found among thirty-two samples. We concluded that the ELISA using antigens secreted from C. pseudotuberculosis T1 strain growth in BHI broth culture can be used for the serodiagnosis of CLA in sheep.

Complete genome sequence, lifestyle, and multi-drug resistance of the human pathogen Corynebacterium resistens DSM 45100 isolated from blood samples of a leukemia patient

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2012-01-01

Background Corynebacterium resistens was initially recovered from human infections and recognized as a new coryneform species that is highly resistant to antimicrobial agents. Bacteremia associated with this organism in immunocompromised patients was rapidly fatal as standard minocycline therapies failed. C. resistens DSM 45100 was isolated from a blood culture of samples taken from a patient with acute myelocytic leukemia. The complete genome sequence of C. resistens DSM 45100 was determined by pyrosequencing to identify genes contributing to multi-drug resistance, virulence, and the lipophilic lifestyle of this newly described human pathogen. Results The genome of C. resistens DSM 45100 consists of a circular chromosome of 2,601,311 bp in size and the 28,312-bp plasmid pJA144188. Metabolic analysis showed that the genome of C. resistens DSM 45100 lacks genes for typical sugar uptake systems, anaplerotic functions, and a fatty acid synthase, explaining the strict lipophilic lifestyle of this species. The genome encodes a broad spectrum of enzymes ensuring the availability of exogenous fatty acids for growth, including predicted virulence factors that probably contribute to fatty acid metabolism by damaging host tissue. C. resistens DSM 45100 is able to use external L-histidine as a combined carbon and nitrogen source, presumably as a result of adaptation to the hitherto unknown habitat on the human skin. Plasmid pJA144188 harbors several genes contributing to antibiotic resistance of C. resistens DSM 45100, including a tetracycline resistance region of the Tet W type known from Lactobacillus reuteri and Streptococcus suis. The tet(W) gene of pJA144188 was cloned in Corynebacterium glutamicum and was shown to confer high levels of resistance to tetracycline, doxycycline, and minocycline in vitro. Conclusions The detected gene repertoire of C. resistens DSM 45100 provides insights into the lipophilic lifestyle and virulence functions of this newly recognized

Metabolic responses to pyruvate kinase deletion in lysine producing Corynebacterium glutamicum

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Wittmann Christoph

2008-03-01

Full Text Available Abstract Background Pyruvate kinase is an important element in flux control of the intermediate metabolism. It catalyzes the irreversible conversion of phosphoenolpyruvate into pyruvate and is under allosteric control. In Corynebacterium glutamicum, this enzyme was regarded as promising target for improved production of lysine, one of the major amino acids in animal nutrition. In pyruvate kinase deficient strains the required equimolar ratio of the two lysine precursors oxaloacetate and pyruvate can be achieved through concerted action of the phosphotransferase system (PTS and phosphoenolpyruvate carboxylase (PEPC, whereby a reduced amount of carbon may be lost as CO2 due to reduced flux into the tricarboxylic acid (TCA cycle. In previous studies, deletion of pyruvate kinase in lysine-producing C. glutamicum, however, did not yield a clear picture and the exact metabolic consequences are not fully understood. Results In this work, deletion of the pyk gene, encoding pyruvate kinase, was carried out in the lysine-producing strain C. glutamicum lysCfbr, expressing a feedback resistant aspartokinase, to investigate the cellular response to deletion of this central glycolytic enzyme. Pyk deletion was achieved by allelic replacement, verified by PCR analysis and the lack of in vitro enzyme activity. The deletion mutant showed an overall growth behavior (specific growth rate, glucose uptake rate, biomass yield which was very similar to that of the parent strain, but differed in slightly reduced lysine formation, increased formation of the overflow metabolites dihydroxyacetone and glycerol and in metabolic fluxes around the pyruvate node. The latter involved a flux shift from pyruvate carboxylase (PC to PEPC, by which the cell maintained anaplerotic supply of the TCA cycle. This created a metabolic by-pass from PEP to pyruvate via malic enzyme demonstrating its contribution to metabolic flexibility of C. glutamicum on glucose. Conclusion The metabolic

Estudo da difteria na cidade do Recife. I. Nota sôbre levantamento de portadores de Corynebacterium diphtheriae no bairro dos Coelhos Survey on diphtheriae carriers in "Bairro dos Coelhos" Recife, Brazil

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Dalva A. Mello

1969-06-01

Full Text Available De uma amostra probabilística do bairro dos Coelhos da cidade do Recife, 410 indivíduos foram examinados para verificação de portadores de difteria. Sòmente duas amostras de C. diphtheriae foram isoladas de duas crianças de 8 a 9 anos, as quais não apresentaram sintomatologia compatível com o quadro diftérico.From a limited population living around the University Hospital in Recife, Brazil a randomic sample was examined in order to identify diphtheria carriers. Swabs were made from 410 persons in a house-to-house survey. Two strains of Corynebacterium diphtheriae were isolated from healthy 8 and 9-year old children.

Utilization of fermentation waste (Corynebacterium glutamicum) for biosorption of Reactive Black 5 from aqueous solution

International Nuclear Information System (INIS)

Vijayaraghavan, K.; Yun, Yeoung-Sang

2007-01-01

A fermentation waste, Corynebacterium glutamicum, was successfully employed as a biosorbent for Reactive Black 5 (RB5) from aqueous solution. This paper initially studied the effect of pretreatment on the biosorption capacity of C. glutamicum toward RB5, using several chemical agents, such as HCl, H 2 SO 4 , HNO 3 , NaOH, Na 2 CO 3 , CaCl 2 and NaCl. Among these reagents, 0.1 M HNO 3 gave the maximum enhancement of the RB5 uptake, exhibiting 195 mg/g at pH 1 with an initial RB5 concentration of 500 mg/l. The solution pH and temperature were found to affect the biosorption capacity, and the biosorption isotherms derived at different pHs and temperatures revealed that a low pH (pH 1) and high temperature (35 deg. C) favored biosorption. The biosorption isotherm was well represented using three-parameter models (Redlich-Peterson and Sips) compared to two-parameter models (Langmuir and Freundlich models). As a result, high correlation coefficients and low average percentage error values were observed for three-parameter models. A maximum RB5 uptake of 419 mg/g was obtained at pH 1 and a temperature of 35 deg. C, according to the Langmuir model. The kinetics of the biosorption process with different initial concentrations (500-2000 mg/l) was also monitored, and the data were analyzed using pseudo-first and pseudo-second order models, with the latter describing the data well. Various thermodynamic parameters, such as ΔG o , ΔH o and ΔS o , were calculated, indicating that the present system was a spontaneous and endothermic process. The use of a 0.1 M NaOH solution successfully desorbed almost all the dye molecules from dye-loaded C. glutamicum biomass at different solid-to-liquid ratios examined

Transcriptome and Multivariable Data Analysis of Corynebacterium glutamicum under Different Dissolved Oxygen Conditions in Bioreactors

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Sun, Yang; Guo, Wenwen; Wang, Fen; Peng, Feng; Yang, Yankun; Dai, Xiaofeng; Liu, Xiuxia; Bai, Zhonghu

2016-01-01

Dissolved oxygen (DO) is an important factor in the fermentation process of Corynebacterium glutamicum, which is a widely used aerobic microbe in bio-industry. Herein, we described RNA-seq for C. glutamicum under different DO levels (50%, 30% and 0%) in 5 L bioreactors. Multivariate data analysis (MVDA) models were used to analyze the RNA-seq and metabolism data to investigate the global effect of DO on the transcriptional distinction of the substance and energy metabolism of C. glutamicum. The results showed that there were 39 and 236 differentially expressed genes (DEGs) under the 50% and 0% DO conditions, respectively, compared to the 30% DO condition. Key genes and pathways affected by DO were analyzed, and the result of the MVDA and RNA-seq revealed that different DO levels in the fermenter had large effects on the substance and energy metabolism and cellular redox balance of C. glutamicum. At low DO, the glycolysis pathway was up-regulated, and TCA was shunted by the up-regulation of the glyoxylate pathway and over-production of amino acids, including valine, cysteine and arginine. Due to the lack of electron-acceptor oxygen, 7 genes related to the electron transfer chain were changed, causing changes in the intracellular ATP content at 0% and 30% DO. The metabolic flux was changed to rebalance the cellular redox. This study applied deep sequencing to identify a wealth of genes and pathways that changed under different DO conditions and provided an overall comprehensive view of the metabolism of C. glutamicum. The results provide potential ways to improve the oxygen tolerance of C. glutamicum and to modify the metabolic flux for amino acid production and heterologous protein expression. PMID:27907077

Enhanced production of recombinant proteins with Corynebacterium glutamicum by deletion of insertion sequences (IS elements).

Science.gov (United States)

Choi, Jae Woong; Yim, Sung Sun; Kim, Min Jeong; Jeong, Ki Jun

2015-12-29

In most bacteria, various jumping genetic elements including insertion sequences elements (IS elements) cause a variety of genetic rearrangements resulting in harmful effects such as genome and recombinant plasmid instability. The genetic stability of a plasmid in a host is critical for high-level production of recombinant proteins, and in this regard, the development of an IS element-free strain could be a useful strategy for the enhanced production of recombinant proteins. Corynebacterium glutamicum, which is a workhorse in the industrial-scale production of various biomolecules including recombinant proteins, also has several IS elements, and it is necessary to identify the critical IS elements and to develop IS element deleted strain. From the cultivation of C. glutamicum harboring a plasmid for green fluorescent protein (GFP) gene expression, non-fluorescent clones were isolated by FACS (fluorescent activated cell sorting). All the isolated clones had insertions of IS elements in the GFP coding region, and two major IS elements (ISCg1 and ISCg2 families) were identified. By co-cultivating cells harboring either the isolated IS element-inserted plasmid or intact plasmid, it was clearly confirmed that cells harboring the IS element-inserted plasmids became dominant during the cultivation due to their growth advantage over cells containing intact plasmids, which can cause a significant reduction in recombinant protein production during cultivation. To minimize the harmful effects of IS elements on the expression of heterologous genes in C. glutamicum, two IS element free C. glutamicum strains were developed in which each major IS element was deleted, and enhanced productivity in the engineered C. glutamicum strain was successfully demonstrated with three models: GFP, poly(3-hydroxybutyrate) [P(3HB)] and γ-aminobutyrate (GABA). Our findings clearly indicate that the hopping of IS elements could be detrimental to the production of recombinant proteins in C

Analysis of SOS-Induced Spontaneous Prophage Induction in Corynebacterium glutamicum at the Single-Cell Level

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Nanda, Arun M.; Heyer, Antonia; Krämer, Christina; Grünberger, Alexander; Kohlheyer, Dietrich

2014-01-01

The genome of the Gram-positive soil bacterium Corynebacterium glutamicum ATCC 13032 contains three integrated prophage elements (CGP1 to -3). Recently, it was shown that the large lysogenic prophage CGP3 (∼187 kbp) is excised spontaneously in a small number of cells. In this study, we provide evidence that a spontaneously induced SOS response is partly responsible for the observed spontaneous CGP3 induction. Whereas previous studies focused mainly on the induction of prophages at the population level, we analyzed the spontaneous CGP3 induction at the single-cell level using promoters of phage genes (Pint2 and Plysin) fused to reporter genes encoding fluorescent proteins. Flow-cytometric analysis revealed a spontaneous CGP3 activity in about 0.01 to 0.08% of the cells grown in standard minimal medium, which displayed a significantly reduced viability. A PrecA-eyfp promoter fusion revealed that a small fraction of C. glutamicum cells (∼0.2%) exhibited a spontaneous induction of the SOS response. Correlation of PrecA to the activity of downstream SOS genes (PdivS and PrecN) confirmed a bona fide induction of this stress response rather than stochastic gene expression. Interestingly, the reporter output of PrecA and CGP3 promoter fusions displayed a positive correlation at the single-cell level (ρ = 0.44 to 0.77). Furthermore, analysis of the PrecA-eyfp/Pint2-e2-crimson strain during growth revealed the highest percentage of spontaneous PrecA and Pint2 activity in the early exponential phase, when fast replication occurs. Based on these studies, we postulate that spontaneously occurring DNA damage induces the SOS response, which in turn triggers the induction of lysogenic prophages. PMID:24163339

Selective oxidation of trimethylolpropane to 2,2-bis(hydroxymethyl)butyric acid using growing cells of Corynebacterium sp. ATCC 21245.

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Sayed, Mahmoud; Dishisha, Tarek; Sayed, Waiel F; Salem, Wesam M; Temerk, Hanan A; Pyo, Sang-Hyun

2016-03-10

Multifunctional chemicals including hydroxycarboxylic acids are gaining increasing interest due to their growing applications in the polymer industry. One approach for their production is a biological selective oxidation of polyols, which is difficult to achieve by conventional chemical catalysis. In the present study, trimethylolpropane (TMP), a trihydric alcohol, was subjected to selective oxidation using growing cells of Corynebacterium sp. ATCC 21245 as a biocatalyst and yielding the dihydroxy-monocarboxylic acid, 2,2-bis(hydroxymethyl)butyric acid (BHMB). The study revealed that co-substrates are crucial for this reaction. Among the different evaluated co-substrates, a mixture of glucose, xylose and acetate at a ratio of 5:5:2 was found optimum. The optimal conditions for biotransformation were pH 8, 1v/v/m airflow and 500rpm stirring speed. In batch mode of operation, 70.6% of 5g/l TMP was converted to BHMB in 10 days. For recovery of the product the adsorption pattern of BHMB to the anion exchange resin, Ambersep(®) 900 (OH(-)), was investigated in batch and column experiments giving maximum static and dynamic binding capacities of 135 and 144mg/g resin, respectively. BHMB was separated with 89.7% of recovery yield from the fermentation broth. The approach is applicable for selective oxidation of other highly branched polyols by biotransformation. Copyright © 2016 Elsevier B.V. All rights reserved.

C1 Metabolism in Corynebacterium glutamicum: an Endogenous Pathway for Oxidation of Methanol to Carbon Dioxide

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Witthoff, Sabrina; Mühlroth, Alice

2013-01-01

Methanol is considered an interesting carbon source in “bio-based” microbial production processes. Since Corynebacterium glutamicum is an important host in industrial biotechnology, in particular for amino acid production, we performed studies of the response of this organism to methanol. The C. glutamicum wild type was able to convert 13C-labeled methanol to 13CO2. Analysis of global gene expression in the presence of methanol revealed several genes of ethanol catabolism to be upregulated, indicating that some of the corresponding enzymes are involved in methanol oxidation. Indeed, a mutant lacking the alcohol dehydrogenase gene adhA showed a 62% reduced methanol consumption rate, indicating that AdhA is mainly responsible for methanol oxidation to formaldehyde. Further studies revealed that oxidation of formaldehyde to formate is catalyzed predominantly by two enzymes, the acetaldehyde dehydrogenase Ald and the mycothiol-dependent formaldehyde dehydrogenase AdhE. The Δald ΔadhE and Δald ΔmshC deletion mutants were severely impaired in their ability to oxidize formaldehyde, but residual methanol oxidation to CO2 was still possible. The oxidation of formate to CO2 is catalyzed by the formate dehydrogenase FdhF, recently identified by us. Similar to the case with ethanol, methanol catabolism is subject to carbon catabolite repression in the presence of glucose and is dependent on the transcriptional regulator RamA, which was previously shown to be essential for expression of adhA and ald. In conclusion, we were able to show that C. glutamicum possesses an endogenous pathway for methanol oxidation to CO2 and to identify the enzymes and a transcriptional regulator involved in this pathway. PMID:24014532

From zero to hero - production of bio-based nylon from renewable resources using engineered Corynebacterium glutamicum.

Science.gov (United States)

Kind, Stefanie; Neubauer, Steffi; Becker, Judith; Yamamoto, Motonori; Völkert, Martin; Abendroth, Gregory von; Zelder, Oskar; Wittmann, Christoph

2014-09-01

Polyamides are important industrial polymers. Currently, they are produced exclusively from petrochemical monomers. Herein, we report the production of a novel bio-nylon, PA5.10 through an integration of biological and chemical approaches. First, systems metabolic engineering of Corynebacterium glutamicum was used to create an effective microbial cell factory for the production of diaminopentane as the polymer building block. In this way, a hyper-producer, with a high diaminopentane yield of 41% in shake flask culture, was generated. Subsequent fed-batch production of C. glutamicum DAP-16 allowed a molar yield of 50%, a productivity of 2.2gL(-1)h(-1), and a final titer of 88gL(-1). The streamlined producer accumulated diaminopentane without generating any by-products. Solvent extraction from alkalized broth and two-step distillation provided highly pure diaminopentane (99.8%), which was then directly accessible for poly-condensation. Chemical polymerization with sebacic acid, a ten-carbon dicarboxylic acid derived from castor plant oil, yielded the bio-nylon, PA5.10. In pure form and reinforced with glass fibers, the novel 100% bio-polyamide achieved an excellent melting temperature and the mechanical strength of the well-established petrochemical polymers, PA6 and PA6.6. It even outperformed the oil-based products in terms of having a 6% lower density. It thus holds high promise for applications in energy-friendly transportation. The demonstration of a novel route for generation of bio-based nylon from renewable sources opens the way to production of sustainable bio-polymers with enhanced material properties and represents a milestone in industrial production. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Chassis organism from Corynebacterium glutamicum--a top-down approach to identify and delete irrelevant gene clusters.

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Unthan, Simon; Baumgart, Meike; Radek, Andreas; Herbst, Marius; Siebert, Daniel; Brühl, Natalie; Bartsch, Anna; Bott, Michael; Wiechert, Wolfgang; Marin, Kay; Hans, Stephan; Krämer, Reinhard; Seibold, Gerd; Frunzke, Julia; Kalinowski, Jörn; Rückert, Christian; Wendisch, Volker F; Noack, Stephan

2015-02-01

For synthetic biology applications, a robust structural basis is required, which can be constructed either from scratch or in a top-down approach starting from any existing organism. In this study, we initiated the top-down construction of a chassis organism from Corynebacterium glutamicum ATCC 13032, aiming for the relevant gene set to maintain its fast growth on defined medium. We evaluated each native gene for its essentiality considering expression levels, phylogenetic conservation, and knockout data. Based on this classification, we determined 41 gene clusters ranging from 3.7 to 49.7 kbp as target sites for deletion. 36 deletions were successful and 10 genome-reduced strains showed impaired growth rates, indicating that genes were hit, which are relevant to maintain biological fitness at wild-type level. In contrast, 26 deleted clusters were found to include exclusively irrelevant genes for growth on defined medium. A combinatory deletion of all irrelevant gene clusters would, in a prophage-free strain, decrease the size of the native genome by about 722 kbp (22%) to 2561 kbp. Finally, five combinatory deletions of irrelevant gene clusters were investigated. The study introduces the novel concept of relevant genes and demonstrates general strategies to construct a chassis suitable for biotechnological application. © 2014 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs Licence, which permits use and distribution in any medium, provided the original work is properly cited, the use is non- commercial and no modifications or adaptations are made.

Production of carbon-13-labeled cadaverine by engineered Corynebacterium glutamicum using carbon-13-labeled methanol as co-substrate.

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Leßmeier, Lennart; Pfeifenschneider, Johannes; Carnicer, Marc; Heux, Stephanie; Portais, Jean-Charles; Wendisch, Volker F

2015-12-01

Methanol, a one-carbon compound, can be utilized by a variety of bacteria and other organisms as carbon and energy source and is regarded as a promising substrate for biotechnological production. In this study, a strain of non-methylotrophic Corynebacterium glutamicum, which was able to produce the polyamide building block cadaverine as non-native product, was engineered for co-utilization of methanol. Expression of the gene encoding NAD+-dependent methanol dehydrogenase (Mdh) from the natural methylotroph Bacillus methanolicus increased methanol oxidation. Deletion of the endogenous aldehyde dehydrogenase genes ald and fadH prevented methanol oxidation to carbon dioxide and formaldehyde detoxification via the linear formaldehyde dissimilation pathway. Heterologous expression of genes for the key enzymes hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase of the ribulose monophosphate (RuMP) pathway in this strain restored growth in the presence of methanol or formaldehyde, which suggested efficient formaldehyde detoxification involving RuMP key enzymes. While growth with methanol as sole carbon source was not observed, the fate of 13C-methanol added as co-substrate to sugars was followed and the isotopologue distribution indicated incorporation into central metabolites and in vivo activity of the RuMP pathway. In addition, 13C-label from methanol was traced to the secreted product cadaverine. Thus, this synthetic biology approach led to a C. glutamicum strain that converted the non-natural carbon substrate methanol at least partially to the non-native product cadaverine.

Optimization of the IPP Precursor Supply for the Production of Lycopene, Decaprenoxanthin and Astaxanthin by Corynebacterium glutamicum

International Nuclear Information System (INIS)

Heider, Sabine A. E.; Wolf, Natalie; Hofemeier, Arne; Peters-Wendisch, Petra; Wendisch, Volker F.

2014-01-01

The biotechnologically relevant bacterium Corynebacterium glutamicum, currently used for the million ton-scale production of amino acids for the food and feed industries, is pigmented due to synthesis of the rare cyclic C50 carotenoid decaprenoxanthin and its glucosides. The precursors of carotenoid biosynthesis, isopenthenyl pyrophosphate (IPP) and its isomer dimethylallyl pyrophosphate, are synthesized in this organism via the methylerythritol phosphate (MEP) or non-mevalonate pathway. Terminal pathway engineering in recombinant C. glutamicum permitted the production of various non-native C50 and C40 carotenoids. Here, the role of engineering isoprenoid precursor supply for lycopene production by C. glutamicum was characterized. Overexpression of dxs encoding the enzyme that catalyzes the first committed step of the MEP-pathway by chromosomal promoter exchange in a prophage-cured, genome-reduced C. glutamicum strain improved lycopene formation. Similarly, an increased IPP supply was achieved by chromosomal integration of two artificial operons comprising MEP pathway genes under the control of a constitutive promoter. Combined overexpression of dxs and the other six MEP pathways genes in C. glutamicum strain LYC3-MEP was not synergistic with respect to improving lycopene accumulation. Based on C. glutamicum strain LYC3-MEP, astaxanthin could be produced in the milligrams per gram cell dry weight range when the endogenous genes crtE, crtB, and crtI for conversion of geranylgeranyl pyrophosphate to lycopene were coexpressed with the genes for lycopene cyclase and β-carotene hydroxylase from Pantoea ananatis and carotene C(4) oxygenase from Brevundimonas aurantiaca.

Conservación por congelación de Bordetella pertussis y Corynebacterium diphtheriae, empleados en la producción de vacunas para uso humano

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Yilian Plasencia,

2000-11-01

Full Text Available En el presente estudio se evaluó el método de congelación a –70ºC para la preservación de Bordetella pertussis y Corynebacterium diphtheriae. Para verificar el sustento de los cultivos se realizó un adecuado control de calidad, que incluyó comprobación de pureza, viabilidad y estabilidad de las propiedades de interés. En este trabajo se probaron diferentes formulaciones. Se seleccionó la que arrojó los mejores resultados y se realizó un estudio de mantenimiento de las características evaluadas durante el tiempo. Para medir determinados parámetros se realizaron procesos a escala industrial, empleándose para esto un biorreactor Chemap de 35 L. Se tomaron como referencia los valores obtenidos por las cepas conservadas por liofilización. De esta forma se buscaron alternativas y soluciones a problemas presentados en su conservación. Los resultados obtenidos sugieren la posible inclusión en el Programa de Mantenimiento establecido.

Analysis of mutations in DNA gyrase and topoisomerase IV of Ureaplasma urealyticum and Ureaplasma parvum serovars resistant to fluoroquinolones.

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Piccinelli, Giorgio; Gargiulo, Franco; Biscaro, Valeria; Caccuri, Francesca; Caruso, Arnaldo; De Francesco, Maria Antonia

2017-01-01

This study aims to determine the prevalence of fluoroquinolone resistance of Ureaplasma biovars and serovars isolated from urogenital clinical samples and determine the underlying molecular mechanism for quinolone resistance for all resistant isolates. Of 105 samples confirmed as positive for U. urealyticum/U. parvum, 85 were resistant to quinolones by the Mycoplasma-IST2 kit. However, only 43 out of 85 quinolone resistant isolates had amino acid substitutions in GyrA, GyrB, ParC and ParE proteins underlining that this assay have mis-identified as fluoroquinolone resistant 42 isolates. The known ParC E87K and ParC S83L mutations were found in 1 and 10 isolates, respectively. An original mutation of ureaplasmal ParC (E87Q, 1 isolate) was found. Furthermore, we found a ParE R448K mutation in one isolate, already described. Among the additional alterations detected, the most prevalent mutation found was L176F in GyrA protein in 18 isolates with single infection and in 3 isolates with mixed ureaplasma infections. Mutations in GyrB (E502Q, 4 isolates), ParE (Q412K, Q412P, Q412T, 3 independent isolates), whose role is unknown, were also found. Other sporadic mutations in the four genes were identified. This investigation is the result of monitoring the data for molecular fluoroquinone resistance in Ureaplasma spp. in Italy. Resulting that this acquired resistance is high and that continued local epidemiological studies are essential to monitor and document their antimicrobial resistance trends. Copyright © 2016 Elsevier B.V. All rights reserved.

Role of collector alternating charged patches on transport of Cryptosporidium parvum oocyst in a patchwise charged heterogeneous micromodel

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Liu, Yuanyuan; Zhang, Changyong; Hu, Dehong; Kuhlenschmidt, Mark S.; Kuhlenschmidt, Theresa B.; Mylon, Steven E.; Kong, Rong; Bhargava, Rohit; Nguyen, Thanh H.

2013-02-04

The role of collector surface charge heterogeneity on transport of Cryptosporidium parvum oocyst and carboxylate microsphere in 2-dimensional micromodels was studied. The cylindrical silica collectors within the micromodels were coated with 0, 10, 20, 50 and 100% Fe2O3 patches. The experimental values of average single collector removal efficiencies (η) of the Fe2O3 patches and on the entire collectors were determined. In the presence of significant (>3500 kT) Derjaguin–Landau–Verwey–Overbeek (DLVO) energy barrier between the microspheres and the silica collectors at pH 5.8 and 8.1, the values of η determined for Fe2O3 patches were significantly less (p < 0.05, t-test) than that obtained for collectors coated entirely with Fe2O3. However, η on Fe2O3 patches for microspheres at pH 4.4 and for oocysts at pH 5.8 and 8.1, where the DLVO energy barrier was relatively small (ca. 200-360 kT), were significantly greater (p < 0.05, t-test) than that on the collectors coated entirely with Fe2O3. The dependence of η determined for Fe2O3 patches on the DLVO energy barrier indicated the importance of periodic favorable and unfavorable electrostatic interactions between colloids and collectors with alternating Fe2O3 and silica patches. Differences between experimentally determined η and that predicted by a patchwise geochemical heterogeneous model was observed, but can be explained by the model’s lack of consideration for the spatial distribution of charge heterogeneity on the collector surface and colloid migration on patchwise heterogeneous collectors.

Production of L-glutamic Acid with Corynebacterium glutamicum (NCIM 2168) and Pseudomonas reptilivora (NCIM 2598): A Study on Immobilization and Reusability.

Science.gov (United States)

Shyamkumar, Rajaram; Moorthy, Innasi Muthu Ganesh; Ponmurugan, Karuppiah; Baskar, Rajoo

2014-07-01

L-glutamic acid is one of the major amino acids that is present in a wide variety of foods. It is mainly used as a food additive and flavor enhancer in the form of sodium salt. Corynebacterium glutamicum (C. glutamicum) is one of the major organisms widely used for glutamic acid production. The study was dealing with immobilization of C. glutamicum and mixed culture of C. glutamicum and Pseudomonas reptilivora (P. reptilivora) for L-glutamic acid production using submerged fermentation. 2, 3 and 5% sodium alginate concentrations were used for production and reusability of immobilized cells for 5 more trials. The results revealed that 2% sodium alginate concentration produced the highest yield (13.026±0.247 g/l by C. glutamicum and 16.026±0.475 g/l by mixed immobilized culture). Moreover, reusability of immobilized cells was evaluated in 2% concentration with 5 more trials. However, when the number of cycles increased, the production of L-glutamic acid decreased. Production of glutamic acid using optimized medium minimizes the time needed for designing the medium composition. It also minimizes external contamination. Glutamic acid production gradually decreased due to multiple uses of beads and consequently it reduces the shelf life.

[Construction of Corynebacterium crenatum AS 1.542 δ argR and analysis of transcriptional levels of the related genes of arginine biosynthetic pathway].

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Chen, Xuelan; Tang, Li; Jiao, Haitao; Xu, Feng; Xiong, Yonghua

2013-01-04

ArgR, coded by the argR gene from Corynebacterium crenatum AS 1.542, acts as a negative regulator in arginine biosynthetic pathway. However, the effect of argR on transcriptional levels of the related biosynthetic genes has not been reported. Here, we constructed a deletion mutant of argR gene: C. crenatum AS 1.542 Delta argR using marker-less knockout technology, and compared the changes of transcriptional levels of the arginine biosynthetic genes between the mutant strain and the wild-type strain. We used marker-less knockout technology to construct C. crenatum AS 1.542 Delta argR and analyzed the changes of the relate genes at the transcriptional level using real-time fluorescence quantitative PCR. C. crenatum AS 1.542 Delta argR was successfully obtained and the transcriptional level of arginine biosynthetic genes in this mutant increased significantly with an average of about 162.1 folds. The arginine biosynthetic genes in C. crenatum are clearly controlled by the negative regulator ArgR. However, the deletion of this regulator does not result in a clear change in arginine production in the bacteria.

Synthesis and characterisation of Cu(II), Ni(II), Mn(II), Zn(II) and VO(II ...

Indian Academy of Sciences (India)

Unknown

Synthesis and characterisation of Cu(II), Ni(II), Mn(II), Zn(II) and VO(II) Schiff base complexes derived from o-phenylenediamine and acetoacetanilide. N RAMAN*, Y PITCHAIKANI RAJA and A KULANDAISAMY. Department of Chemistry, VHNSN College, Virudhunagar 626 001, India e-mail: ra_man@123india.com.

Biologically active new Fe(II, Co(II, Ni(II, Cu(II, Zn(II and Cd(II complexes of N-(2-thienylmethylenemethanamine

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C. SPÎNU

2008-04-01

Full Text Available Iron(II, cobalt(II, nickel (II, copper (II, zinc(II and cadmium(II complexes of the type ML2Cl2, where M is a metal and L is the Schiff base N-(2-thienylmethylenemethanamine (TNAM formed by the condensation of 2-thiophenecarboxaldehyde and methylamine, were prepared and characterized by elemental analysis as well as magnetic and spectroscopic measurements. The elemental analyses suggest the stoichiometry to be 1:2 (metal:ligand. Magnetic susceptibility data coupled with electronic, ESR and Mössbauer spectra suggest a distorted octahedral structure for the Fe(II, Co(II and Ni(II complexes, a square-planar geometry for the Cu(II compound and a tetrahedral geometry for the Zn(II and Cd(II complexes. The infrared and NMR spectra of the complexes agree with co-ordination to the central metal atom through nitrogen and sulphur atoms. Conductance measurements suggest the non-electrolytic nature of the complexes, except for the Cu(II, Zn(II and Cd(II complexes, which are 1:2 electrolytes. The Schiff base and its metal chelates were screened for their biological activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and the metal chelates were found to possess better antibacterial activity than that of the uncomplexed Schiff base.

Formation of xylitol and xylitol-5-phosphate and its impact on growth of d-xylose-utilizing Corynebacterium glutamicum strains.

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Radek, Andreas; Müller, Moritz-Fabian; Gätgens, Jochem; Eggeling, Lothar; Krumbach, Karin; Marienhagen, Jan; Noack, Stephan

2016-08-10

Wild-type Corynebacterium glutamicum has no endogenous metabolic activity for utilizing the lignocellulosic pentose d-xylose for cell growth. Therefore, two different engineering approaches have been pursued resulting in platform strains harbouring a functional version of either the Isomerase (ISO) or the Weimberg (WMB) pathway for d-xylose assimilation. In a previous study we found for C. glutamicum WMB by-product formation of xylitol during growth on d-xylose and speculated that the observed lower growth rates are due to the growth inhibiting effect of this compound. Based on a detailed phenotyping of the ISO, WMB and the wild-type strain of C. glutamicum, we here show that this organism has a natural capability to synthesize xylitol from d-xylose under aerobic cultivation conditions. We furthermore observed the intracellular accumulation of xylitol-5-phosphate as a result of the intracellular phosphorylation of xylitol, which was particularly pronounced in the C. glutamicum ISO strain. Interestingly, low amounts of supplemented xylitol strongly inhibit growth of this strain on d-xylose, d-glucose and d-arabitol. These findings demonstrate that xylitol is a suitable substrate of the endogenous xylulokinase (XK, encoded by xylB) and its overexpression in the ISO strain leads to a significant phosphorylation of xylitol in C. glutamicum. Therefore, in order to circumvent cytotoxicity by xylitol-5-phosphate, the WMB pathway represents an interesting alternative route for engineering C. glutamicum towards efficient d-xylose utilization. Copyright © 2016 Elsevier B.V. All rights reserved.

Complexes of cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II) and dioxouranium(II) with thiophene-2-aldehydethiosemicarbazone

International Nuclear Information System (INIS)

Singh, Balwan; Misra, Harihar

1986-01-01

Metal complexes of thiosemicarbazides have been known for their pharmacological applications. Significant antitubercular, fungicidal and antiviral activities have been reported for thiosemicarbazides and their derivatives. The present study describes the systhesis and characterisation of complexes of Co II , Cu II , Zn II ,Cd II and UO II with thiosemicarbazone obtained by condensing thiophene-2-aldehyde with thiosemicarbazide. 17 refs., 2 tables. (author)

Mn(II), Zn(II) and VO(II) Schiff

Indian Academy of Sciences (India)

Home; Journals; Journal of Chemical Sciences; Volume 113; Issue 3. Synthesis and characterisation of Cu(II), Ni(II), Mn(II), Zn(II) and VO(II) Schiff base complexes derived from o-phenylenediamine and acetoacetanilide. N Raman Y Pitchaikani Raja A Kulandaisamy. Inorganic Volume 113 Issue 3 June 2001 pp 183-189 ...

Molecular fingerprinting of Cryptosporidium oocysts isolated during water monitoring.

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Nichols, Rosely A B; Campbell, Brian M; Smith, Huw V

2006-08-01

We developed and validated a PCR-based method for identifying Cryptosporidium species and/or genotypes present on oocyst-positive microscope slides. The method involves removing coverslips and oocysts from previously examined slides followed by DNA extraction. We tested four loci, the 18S rRNA gene (N18SDIAG and N18SXIAO), the Cryptosporidium oocyst wall protein (COWP) gene (STN-COWP), and the dihydrofolate reductase (dhfr) gene (by multiplex allele-specific PCR), for amplifying DNA from low densities of Cryptosporidium parvum oocysts experimentally seeded onto microscope slides. The N18SDIAG locus performed consistently better than the other three tested. Purified oocysts from humans infected with C. felis, C. hominis, and C. parvum and commercially purchased C. muris were used to determine the sensitivities of three loci (N18SDIAG, STN-COWP, and N18SXIAO) to detect low oocyst densities. The N18SDIAG primers provided the greatest number of positive results, followed by the N18SXIAO primers and then the STN-COWP primers. Some oocyst-positive slides failed to generate a PCR product at any of the loci tested, but the limit of sensitivity is not entirely based on oocyst number. Sixteen of 33 environmental water monitoring Cryptosporidium slides tested (oocyst numbers ranging from 1 to 130) contained mixed Cryptosporidium species. The species/genotypes most commonly found were C. muris or C. andersoni, C. hominis or C. parvum, and C. meleagridis or Cryptosporidium sp. cervine, ferret, and mouse genotypes. Oocysts on one slide contained Cryptosporidium muskrat genotype II DNA.

A thiol-disulfide oxidoreductase of the Gram-positive pathogen Corynebacterium diphtheriae is essential for viability, pilus assembly, toxin production and virulence.

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Reardon-Robinson, Melissa E; Osipiuk, Jerzy; Jooya, Neda; Chang, Chungyu; Joachimiak, Andrzej; Das, Asis; Ton-That, Hung

2015-12-01

The Gram-positive pathogen Corynebacterium diphtheriae exports through the Sec apparatus many extracellular proteins that include the key virulence factors diphtheria toxin and the adhesive pili. How these proteins attain their native conformations after translocation as unfolded precursors remains elusive. The fact that the majority of these exported proteins contain multiple cysteine residues and that several membrane-bound oxidoreductases are encoded in the corynebacterial genome suggests the existence of an oxidative protein-folding pathway in this organism. Here we show that the shaft pilin SpaA harbors a disulfide bond in vivo and alanine substitution of these cysteines abrogates SpaA polymerization and leads to the secretion of degraded SpaA peptides. We then identified a thiol-disulfide oxidoreductase (MdbA), whose structure exhibits a conserved thioredoxin-like domain with a CPHC active site. Remarkably, deletion of mdbA results in a severe temperature-sensitive cell division phenotype. This mutant also fails to assemble pilus structures and is greatly defective in toxin production. Consistent with these defects, the ΔmdbA mutant is attenuated in a guinea pig model of diphtheritic toxemia. Given its diverse cellular functions in cell division, pilus assembly and toxin production, we propose that MdbA is a component of the general oxidative folding machine in C. diphtheriae. © 2015 John Wiley & Sons Ltd.

Efficient production of α-ketoglutarate in the gdh deleted Corynebacterium glutamicum by novel double-phase pH and biotin control strategy.

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Li, Yanjun; Sun, Lanchao; Feng, Jia; Wu, Ruifang; Xu, Qingyang; Zhang, Chenglin; Chen, Ning; Xie, Xixian

2016-06-01

Production of L-glutamate using a biotin-deficient strain of Corynebacterium glutamicum has a long history. The process is achieved by controlling biotin at suboptimal dose in the initial fermentation medium, meanwhile feeding NH4OH to adjust pH so that α-ketoglutarate (α-KG) can be converted to L-glutamate. In this study, we deleted glutamate dehydrogenase (gdh1 and gdh2) of C. glutamicum GKG-047, an L-glutamate overproducing strain, to produce α-KG that is the direct precursor of L-glutamate. Based on the method of L-glutamate fermentation, we developed a novel double-phase pH and biotin control strategy for α-KG production. Specifically, NH4OH was added to adjust the pH at the bacterial growth stage and NaOH was used when the cells began to produce acid; besides adding an appropriate amount of biotin in the initial medium, certain amount of additional biotin was supplemented at the middle stage of fermentation to maintain a high cell viability and promote the carbon fixation to the flux of α-KG production. Under this control strategy, 45.6 g/L α-KG accumulated after 30-h fermentation in a 7.5-L fermentor and the productivity and yield achieved were 1.52 g/L/h and 0.42 g/g, respectively.

Characterization and sequence analysis of the F2 promoter from corynephage BFK20

International Nuclear Information System (INIS)

Koptides, M.; Ugorcakova, J.; Baloghova, E.; Bukovska, G.; Timko, J.

1994-01-01

F2 promoter from corynephage BFK20 was isolated and characterized. It was functional in Escherichia coli and Corynebacterium glutamicum. Cloning of the F2 promoter into the pJUP05 promoter probe vector caused an increase of the neomycin phosphotransferase II specific activity. According to the Northern blot hybridization the nptII gene was expressed from the cloned F2 promoter. The apparent transcription start point in E. coli and C. glutamicum was determined. The-35 region of F2 promoter showed high similarity to that of E. coli promoter consensus sequence, but its - 10 region was G+C rich and had no significant homology to that. (author)

Molecular evaluation of 7 sexually transmissible microorganisms in symptomatic and asymptomatic Italian childbearing age women: is Ureaplasma parvum a real innocent bystander?

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Manuela Avolio

2016-10-01

Full Text Available Background: Symptoms of most common bacterial and parasitic sexually transmitted infections tend to be non-specific and typically have a variety of different potential causal agents that may require different treatments. In this field the pathogenic potential of genital Ureaplasma species is still uncertain and debated. The goal of this study was to investigate the prevalence of Chlamydia trachomatis (CT, Neisseria gonorrhoeae (NG, Trichomonas vaginalis (TV, Mycoplasma genitalium (MG, Mycoplasma hominis (MH, Ureaplasma urealyticum (UU and Ureaplasma parvum (UP in a cohort of symptomatic and asymptomatic childbearing age women and to assess the relationships between bacterial vaginosis and symptoms with both UU and UP. Materials and Methods: DNA of 2735 endocervical specimens was consecutively analysed by a commercial multiplex real-time polymerase chain reaction for detection of 7 multiple target sequences simultaneously: CT, NG, TV, MG, MH, UU and UP. Results: Out of the total number of population studied (n=2735, UP was found to be the species with highest prevalence (30.9% followed by MH (6.5%, UU (6.3%, CT (2.6%, MG (0.8% and TV (0.9%. UP single species detection was extremely significant in symptomatic women with normal flora (P<0.0001. The correlation of UP in symptomatic women with bacterial vaginosis was not significant (P=0.3387. Conclusions: Our results suggest a potential specific etiological role to UP, still considered rightly or wrongly innocent bystander, despite the lack so far of specific-species culture tests.

Adsorption of Pb(II), Cu(II), Cd(II), Zn(II), Ni(II), Fe(II), and As(V) on bacterially produced metal sulfides.

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Jong, Tony; Parry, David L

2004-07-01

The adsorption of Pb(II), Cu(II), Cd(II), Zn(II), Ni(II), Fe(II) and As(V) onto bacterially produced metal sulfide (BPMS) material was investigated using a batch equilibrium method. It was found that the sulfide material had adsorptive properties comparable with those of other adsorbents with respect to the specific uptake of a range of metals and, the levels to which dissolved metal concentrations in solution can be reduced. The percentage of adsorption increased with increasing pH and adsorbent dose, but decreased with increasing initial dissolved metal concentration. The pH of the solution was the most important parameter controlling adsorption of Cd(II), Cu(II), Fe(II), Ni(II), Pb(II), Zn(II), and As(V) by BPMS. The adsorption data were successfully modeled using the Langmuir adsorption isotherm. Desorption experiments showed that the reversibility of adsorption was low, suggesting high-affinity adsorption governed by chemisorption. The mechanism of adsorption for the divalent metals was thought to be the formation of strong, inner-sphere complexes involving surface hydroxyl groups. However, the mechanism for the adsorption of As(V) by BPMS appears to be distinct from that of surface hydroxyl exchange. These results have important implications to the management of metal sulfide sludge produced by bacterial sulfate reduction.

Clinical metagenomic analysis of bacterial communities in breast abscesses of granulomatous mastitis.

Science.gov (United States)

Yu, Hai-Jing; Deng, Hua; Ma, Jian; Huang, Shu-Jun; Yang, Jian-Min; Huang, Yan-Fen; Mu, Xiao-Ping; Zhang, Liang; Wang, Qi

2016-12-01

Granulomatous mastitis (GM) is a chronic inflammatory breast lesion. Its etiology remains incompletely defined. Although mounting evidence suggests the involvement of Corynebacterium in GM, there has been no systematic study of GM bacteriology using -omics technology. The bacterial diversity and relative abundances in breast abscesses from 19 women with GM were investigated using 16S rDNA metagenomic sequencing and Sanger sequencing. A quantitative PCR (qPCR) assay was also developed to identify Corynebacterium kroppenstedtii. A bioinformatic analysis revealed that Corynebacterium was present in the 19 GM patients, with abundances ranging from 1.1% to 58.9%. Of note, Corynebacterium was the most abundant taxon in seven patients (more than a third of the subjects). The predominance of Corynebacterium kroppenstedtii infection (11 of 19 patients, 57.9%) was confirmed with Sanger sequencing and the qPCR assay. This study profiled the microbiota of patients with GM and indicated an important role for Corynebacterium, and in particular C. kroppenstedtii, in the pathogenesis of this disease. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Growth rates of three geographically separated strains of the ichthyotoxic Prymnesium parvum (Prymnesiophyceae) in response to six different pH levels

Science.gov (United States)

Lysgaard, Maria L.; Eckford-Soper, Lisa; Daugbjerg, Niels

2018-05-01

Continued anthropogenic carbon emissions are expected to cause a decline in global average pH of the oceans to a projected value of 7.8 by the end of the century. Understanding how harmful algal bloom (HAB) species will respond to lowered pH levels will be important when predicting future HAB events and their ecological consequences. In this study, we examined how manipulated pH levels affected the growth rate of three strains of Prymnesium parvum from North America, Denmark and Japan. Triplicate strains were grown under pH conditions ranging from 6.6 to 9.1 to simulate plausible future levels. Different tolerances were evident for all strains. Significantly higher growth rates were observed at pH 6.6-8.1 compared to growth rates at pH 8.6-9.1 and a lower pH limit was not observed. The Japanese strain (NIES-1017) had the highest maximum growth rate of 0.39 divisions day-1 at pH 6.6 but a low tolerance (0.22 divisions day-1) to high levels (pH 9.1) with growth declining markedly after pH 7.6. The Danish (SCCAP K-0081) and North American (UTEX LB 2797) strains had maximum growth rates of 0.26 and 0.35 divisions day-1, respectively between pH 6.6-8.1. Compared to the other two strains the Danish strain had a statistically lower growth rate across all pH treatments. Strain differences were either attributed to their provenance or the length of time the strain had been in culture.

A thioredoxin-dependent peroxiredoxin Q from Corynebacterium glutamicum plays an important role in defense against oxidative stress.

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Tao Su

Full Text Available Peroxiredoxin Q (PrxQ that belonged to the cysteine-based peroxidases has long been identified in numerous bacteria, but the information on the physiological and biochemical functions of PrxQ remain largely lacking in Corynebacterium glutamicum. To better systematically understand PrxQ, we reported that PrxQ from model and important industrial organism C. glutamicum, encoded by the gene ncgl2403 annotated as a putative PrxQ, played important roles in adverse stress resistance. The lack of C. glutamicum prxQ gene resulted in enhanced cell sensitivity, increased ROS accumulation, and elevated protein carbonylation levels under adverse stress conditions. Accordingly, PrxQ-mediated resistance to adverse stresses mainly relied on the degradation of ROS. The physiological roles of PrxQ in resistance to adverse stresses were corroborated by its induced expression under adverse stresses, regulated directly by the stress-responsive ECF-sigma factor SigH. Through catalytical kinetic activity, heterodimer formation, and bacterial two-hybrid analysis, we proved that C. glutamicum PrxQ catalytically eliminated peroxides by exclusively receiving electrons from thioredoxin (Trx/thioredoxin reductase (TrxR system and had a broad range of oxidizing substrates, but a better efficiency for peroxynitrite and cumene hydroperoxide (CHP. Site-directed mutagenesis confirmed that the conserved Cys49 and Cys54 are the peroxide oxidation site and the resolving Cys residue, respectively. It was also discovered that C. glutamicum PrxQ mainly existed in monomer whether under its native state or functional state. Based on these results, a catalytic model of PrxQ is being proposed. Moreover, our result that C. glutamicum PrxQ can prevent the damaging effects of adverse stresses by acting as thioredoxin-dependent monomeric peroxidase could be further applied to improve the survival ability and robustness of the important bacterium during fermentation process.

Characterization of the biotin uptake system encoded by the biotin-inducible bioYMN operon of Corynebacterium glutamicum

Science.gov (United States)

2012-01-01

Background The amino acid-producing Gram-positive Corynebacterium glutamicum is auxotrophic for biotin although biotin ring assembly starting from the precursor pimeloyl-CoA is still functional. It possesses AccBC, the α-subunit of the acyl-carboxylases involved in fatty acid and mycolic acid synthesis, and pyruvate carboxylase as the only biotin-containing proteins. Comparative genome analyses suggested that the putative transport system BioYMN encoded by cg2147, cg2148 and cg2149 might be involved in biotin uptake by C. glutamicum. Results By comparison of global gene expression patterns of cells grown with limiting or excess supply of biotin or with dethiobiotin as supplement replacing biotin revealed that expression of genes coding for enzymes of biotin ring assembly and for the putative uptake system was regulated according to biotin availability. RT-PCR and 5'-RACE experiments demonstrated that the genes bioY, bioM, and bioN are transcribed from one promoter as a single transcript. Biochemical analyses revealed that BioYMN catalyzes the effective uptake of biotin with a concentration of 60 nM biotin supporting a half-maximal transport rate. Maximal biotin uptake rates were at least five fold higher in biotin-limited cells as compared to cells grown with excess biotin. Overexpression of bioYMN led to an at least 50 fold higher biotin uptake rate as compared to the empty vector control. Overproduction of BioYMN alleviated biotin limitation and interfered with triggering L-glutamate production by biotin limitation. Conclusions The operon bioYMN from C. glutamicum was shown to be induced by biotin limitation. Transport assays with radio-labeled biotin revealed that BioYMN functions as a biotin uptake system. Overexpression of bioYMN affected L-glutamate production triggered by biotin limitation. PMID:22243621

Characterization of the biotin uptake system encoded by the biotin-inducible bioYMN operon of Corynebacterium glutamicum.

Science.gov (United States)

Schneider, Jens; Peters-Wendisch, Petra; Stansen, K Corinna; Götker, Susanne; Maximow, Stanislav; Krämer, Reinhard; Wendisch, Volker F

2012-01-13

The amino acid-producing Gram-positive Corynebacterium glutamicum is auxotrophic for biotin although biotin ring assembly starting from the precursor pimeloyl-CoA is still functional. It possesses AccBC, the α-subunit of the acyl-carboxylases involved in fatty acid and mycolic acid synthesis, and pyruvate carboxylase as the only biotin-containing proteins. Comparative genome analyses suggested that the putative transport system BioYMN encoded by cg2147, cg2148 and cg2149 might be involved in biotin uptake by C. glutamicum. By comparison of global gene expression patterns of cells grown with limiting or excess supply of biotin or with dethiobiotin as supplement replacing biotin revealed that expression of genes coding for enzymes of biotin ring assembly and for the putative uptake system was regulated according to biotin availability. RT-PCR and 5'-RACE experiments demonstrated that the genes bioY, bioM, and bioN are transcribed from one promoter as a single transcript. Biochemical analyses revealed that BioYMN catalyzes the effective uptake of biotin with a concentration of 60 nM biotin supporting a half-maximal transport rate. Maximal biotin uptake rates were at least five fold higher in biotin-limited cells as compared to cells grown with excess biotin. Overexpression of bioYMN led to an at least 50 fold higher biotin uptake rate as compared to the empty vector control. Overproduction of BioYMN alleviated biotin limitation and interfered with triggering L-glutamate production by biotin limitation. The operon bioYMN from C. glutamicum was shown to be induced by biotin limitation. Transport assays with radio-labeled biotin revealed that BioYMN functions as a biotin uptake system. Overexpression of bioYMN affected L-glutamate production triggered by biotin limitation.

Effect of biotin on transcription levels of key enzymes and glutamate efflux in glutamate fermentation by Corynebacterium glutamicum.

Science.gov (United States)

Cao, Yan; Duan, Zuoying; Shi, Zhongping

2014-02-01

Biotin is an important factor affecting the performance of glutamate fermentation by biotin auxotrophic Corynebacterium glutamicum and glutamate is over-produced only when initial biotin content is controlled at suitable levels or initial biotin is excessive but with Tween 40 addition during fermentation. The transcription levels of key enzymes at pyruvate, isocitrate and α-ketoglutarate metabolic nodes, as well as transport protein (TP) of glutamate were investigated under the conditions of varied biotin contents and Tween 40 supplementation. When biotin was insufficient, the genes encoding key enzymes and TP were down-regulated in the early production phase, in particular, the transcription level of isocitrate dehydrogenase (ICDH) which was only 2% of that of control. Although the cells' morphology transformation and TP level were not affected, low transcription level of ICDH led to lower final glutamate concentration (64 g/L). When biotin was excessive, the transcription levels of key enzymes were at comparable levels as those of control with ICDH as an exception, which was only 3-22% of control level throughout production phase. In this case, little intracellular glutamate accumulation (1.5 mg/g DCW) and impermeable membrane resulted in non glutamate secretion into broth, even though the quantity of TP was more than 10-folds of control level. Addition of Tween 40 when biotin was excessive stimulated the expression of all key enzymes and TP, intracellular glutamate content was much higher (10-12 mg/g DCW), and final glutamate concentration reached control level (75-80 g/L). Hence, the membrane alteration and TP were indispensable in glutamate secretion. Biotin and Tween 40 influenced the expression level of ICDH and glutamate efflux, thereby influencing glutamate production.

Integration of ARTP mutagenesis with biosensor-mediated high-throughput screening to improve L-serine yield in Corynebacterium glutamicum.

Science.gov (United States)

Zhang, Xin; Zhang, Xiaomei; Xu, Guoqiang; Zhang, Xiaojuan; Shi, Jinsong; Xu, Zhenghong

2018-05-03

L-Serine is widely used in the pharmaceutical, food, and cosmetics industries. Although direct fermentative production of L-serine from sugar in Corynebacterium glutamicum has been achieved, the L-serine yield remains relatively low. In this study, atmospheric and room temperature plasma (ARTP) mutagenesis was used to improve the L-serine yield based on engineered C. glutamicum ΔSSAAI strain. Subsequently, we developed a novel high-throughput screening method using a biosensor constructed based on NCgl0581, a transcriptional factor specifically responsive to L-serine, so that L-serine concentration within single cell of C. glutamicum can be monitored via fluorescence-activated cell sorting (FACS). Novel L-serine-producing mutants were isolated from a large library of mutagenized cells. The mutant strain A36-pDser was screened from 1.2 × 10 5 cells, and the magnesium ion concentration in the medium was optimized specifically for this mutant. C. glutamicum A36-pDser accumulated 34.78 g/L L-serine with a yield of 0.35 g/g sucrose, which were 35.9 and 66.7% higher than those of the parent C. glutamicum ΔSSAAI-pDser strain, respectively. The L-serine yield achieved in this mutant was the highest of all reported L-serine-producing strains of C. glutamicum. Moreover, the whole-genome sequencing identified 11 non-synonymous mutations of genes associated with metabolic and transport pathways, which might be responsible for the higher L-serine production and better cell growth in C. glutamicum A36-pDser. This study explored an effective mutagenesis strategy and reported a novel high-throughput screening method for the development of L-serine-producing strains.

Crecimiento y habilidad decolorante potencial de Hyphomycetes (Deuteromycetes de Río Santiago sobre medio agarizado suplementado con cromóforos sintéticos Growth and potential decolorizing ability of Hyphomycetes (Deuteromycetes from Río Santiago on agar medium supplemented with synthetic chromophores

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Romina Liberto

2005-12-01

Full Text Available Se analizó la capacidad de Dictyosporium triramosum, Minimidochium parvum y Tetraploa aristata, aisladas de materia orgánica colectada en Río Santiago (Provincia de Buenos Aires, Argentina, para crecer y decolorar medios agarizados y suplementados con diferentes cromóforos sintéticos al 0,01 % (p v-1. Cristal violeta y verde brillante redujeron el crecimiento de las 3 cepas revelando los mayores porcentajes de inhibición. Mientras que eosina y rosa de bengala no afectaron a D. triramosum, valores superiores al 50 % de inhibición se observaron en M. parvum y T. aristata. Rojo congo y rojo neutral redujeron a D. triramosum y M. parvum en un 12-17 %, pero no a T. aristata. D. triramosum y T. aristata no resultaron afectados por azul de toluidina, mientras M. parvum fue inhibido por el colorante. Rojo de metilo sólo inhibió a M. parvum y T. aristata. Las 3 cepas probadas revelaron capacidad para decolorar el medio suplementado con azul de toluidina y rojo de metilo. D. triramosum decoloró además el medio suplementado con cristal violeta y rojo congo, y T. aristata el medio con cristal violeta y rojo neutral. Ninguno de los hongos estudiados decoloró los medios con eosina, rosa de bengala y verde brillante.The ability of Dictyosporium triramosum, Minimidochium parvum and Tetraploa aristata, isolated from organic matter collected in Río Santiago (Buenos Aires Province, Argentina, to grow and decolorize agar media supplemented with different synthetic chromophores at 0.01% (w v-1 was analyzed. Crystal violet and brilliant green reduced the growth of the three strains showing the highest inhibition percentages. While eosin and rose bengal did not affect D. triramosum, growth inhibition values superior to 50 % were observed for M. parvum and T. aristata. Congo red and neutral red inhibited growth of both D. triramosum and M. parvum in a 12-17%, but those dyes did not reduced T. aristata growth. D. triramosum and T. aristata were not affected

Synthesis and spectroscopic studies of biologically active tetraazamacrocyclic complexes of Mn(II, Co(II, Ni(II, Pd(II and Pt(II

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Monika Tyagi

2014-01-01

Full Text Available Complexes of Mn(II, Co(II, Ni(II, Pd(II and Pt(II were synthesized with the macrocyclic ligand, i.e., 2,3,9,10-tetraketo-1,4,8,11-tetraazacycoletradecane. The ligand was prepared by the [2 + 2] condensation of diethyloxalate and 1,3-diamino propane and characterized by elemental analysis, mass, IR and 1H NMR spectral studies. All the complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, IR, electronic and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II, Co(II and Ni(II complexes in DMF correspond to non electrolyte nature, whereas Pd(II and Pt(II complexes are 1:2 electrolyte. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II, Co(II and Ni(II complexes, whereas square planar geometry assigned for Pd(II and Pt(II. In vitro the ligand and its metal complexes were evaluated against plant pathogenic fungi (Fusarium odum, Aspergillus niger and Rhizoctonia bataticola and some compounds found to be more active as commercially available fungicide like Chlorothalonil.

Application of DEN refinement and automated model building to a difficult case of molecular-replacement phasing: the structure of a putative succinyl-diaminopimelate desuccinylase from Corynebacterium glutamicum.

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Brunger, Axel T; Das, Debanu; Deacon, Ashley M; Grant, Joanna; Terwilliger, Thomas C; Read, Randy J; Adams, Paul D; Levitt, Michael; Schröder, Gunnar F

2012-04-01

Phasing by molecular replacement remains difficult for targets that are far from the search model or in situations where the crystal diffracts only weakly or to low resolution. Here, the process of determining and refining the structure of Cgl1109, a putative succinyl-diaminopimelate desuccinylase from Corynebacterium glutamicum, at ∼3 Å resolution is described using a combination of homology modeling with MODELLER, molecular-replacement phasing with Phaser, deformable elastic network (DEN) refinement and automated model building using AutoBuild in a semi-automated fashion, followed by final refinement cycles with phenix.refine and Coot. This difficult molecular-replacement case illustrates the power of including DEN restraints derived from a starting model to guide the movements of the model during refinement. The resulting improved model phases provide better starting points for automated model building and produce more significant difference peaks in anomalous difference Fourier maps to locate anomalous scatterers than does standard refinement. This example also illustrates a current limitation of automated procedures that require manual adjustment of local sequence misalignments between the homology model and the target sequence.

Effect of Cu(II), Cd(II) and Zn(II) on Pb(II) biosorption by algae Gelidium-derived materials.

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Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

2008-06-15

Biosorption of Pb(II), Cu(II), Cd(II) and Zn(II) from binary metal solutions onto the algae Gelidium sesquipedale, an algal industrial waste and a waste-based composite material was investigated at pH 5.3, in a batch system. Binary Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II) solutions have been tested. For the same equilibrium concentrations of both metal ions (1 mmol l(-1)), approximately 66, 85 and 86% of the total uptake capacity of the biosorbents is taken by lead ions in the systems Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II), respectively. Two-metal results were fitted to a discrete and a continuous model, showing the inhibition of the primary metal biosorption by the co-cation. The model parameters suggest that Cd(II) and Zn(II) have the same decreasing effect on the Pb(II) uptake capacity. The uptake of Pb(II) was highly sensitive to the presence of Cu(II). From the discrete model it was possible to obtain the Langmuir affinity constant for Pb(II) biosorption. The presence of the co-cations decreases the apparent affinity of Pb(II). The experimental results were successfully fitted by the continuous model, at different pH values, for each biosorbent. The following sequence for the equilibrium affinity constants was found: Pb>Cu>Cd approximately Zn.

Frequency of Chlamydia trachomatis in Ureaplasma-positive healthy women attending their first prenatal visit in a community hospital in Sapporo, Japan.

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Yamazaki, Tomohiro; Matsumoto, Megumi; Matsuo, Junji; Abe, Kiyotaka; Minami, Kunihiro; Yamaguchi, Hiroyuki

2012-04-02

Although Chlamydia trachomatis is the most commonly reported pathogen that causes urogenital infection such as urethritis or cervicitis, Ureaplasma parvum and Ureaplasma urealyticum, which are commensals in the genital tract, have also now been recognized as contributors to urogenital infection. However, whether the presence of either U. parvum or U. urealyticum is related to that of C. trachomatis in the urogenital tract remains unknown. We therefore attempted to estimate by PCR the prevalence of C. trachomatis, U. parvum and U. urealyticum in endocervical samples obtained from healthy women attending their first prenatal visit in Sapporo, Japan. The samples were taken from 303 apparently healthy women, and the extracted DNAs (n = 280) were used for PCR detection targeting C. trachomatis, U. parvum and U. urealyticum. Statistical analysis of the data was performed by Fisher's exact test. PCR detection revealed that the prevalence of C. trachomatis, U. parvum and U. urealyticum was 14.3% (40/280), 41.7% (117/280) and 8.9% (25/280), respectively. C. trachomatis ompA genotype D was most frequently identified. Surprisingly, either C. trachomatis or Ureaplasma spp. was detected in almost half of the healthy women. Mixed infection of C. trachomatis with either U. parvum or U. urealyticum was also observed in 9.2% (26/280) of the women. There was a significant association between C. trachomatis and either U. parvum (p = 0.023) or Ureaplasma total (p = 0.013), but not U. urealyticum (p = 0.275). This study demonstrated that the presence of Ureaplasma had a significant effect on the presence of C. trachomatis in the genital tract of healthy women, suggesting that mixed infection is an important factor in bacterial pathogenesis in the genital tract.

First molecular characterization of Cryptosporidium in Yemen.

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Alyousefi, N A; Mahdy, M A K; Lim, Y A L; Xiao, L; Mahmud, R

2013-05-01

Cryptosporidium is a protozoan parasite of humans and animals and has a worldwide distribution. The parasite has a unique epidemiology in Middle Eastern countries where the IId subtype family of Cryptosporidium parvum dominates. However, there has been no information on Cryptosporidium species in Yemen. Thus, this study was conducted in Yemen to examine the distribution of Cryptosporidium species and subtype families. Fecal samples were collected from 335 patients who attended hospitals in Sana'a city. Cryptosporidium species were determined by PCR and sequence analysis of the 18 s rRNA gene. Cryptosporidium parvum and C. hominis subtypes were identified based on sequence analysis of the 60 kDa glycoprotein (gp60) gene. Out of 335 samples, 33 (9.9%) were positive for Cryptosporidium. Of them, 97% were identified as C. parvum whilst 1 case (3%) was caused by C. hominis. All 7 C. parvum isolates subtyped belonged to the IIaA15G2R1 subtype. The common occurrence of the zoonotic IIa subtype family of C. parvum highlights the potential occurrence of zoonotic transmission of cryptosporidiosis in Yemen. However, this postulation needs confirmation with future molecular epidemiological studies of cryptosporidiosis in both humans and animals in Yemen.

Maternal Azithromycin Therapy for Ureaplasma Intra-Amniotic Infection Delays Preterm Delivery and Reduces Fetal Lung Injury in a Primate Model

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Grigsby, Peta L.; Novy, Miles J.; Sadowsky, Drew W.; Morgan, Terry K.; Long, Mary; Acosta, Ed; Duffy, Lynn B; Waites, Ken B.

2012-01-01

Objective We assessed the efficacy of a maternal multi–dose azithromycin (AZI) regimen, with and without anti–inflammatory agents to delay preterm birth and to mitigate fetal lung injury associated with Ureaplasma parvum intra–amniotic infection (IAI). Study Design Long–term catheterized rhesus monkeys (n=16) received intra–amniotic inoculation of U. parvum (107 CFU/ml, serovar 1). After contraction onset, rhesus monkeys received either no treatment (n=6); AZI (12.5mg/kg, q12h, IV for 10 days; n=5); or AZI plus dexamethasone (DEX) and indomethacin (INDO; n=5). Outcomes included amniotic fluid pro–inflammatory mediators, U. parvum cultures & PCR, AZI pharmacokinetics and the extent of fetal lung inflammation. Results Maternal AZI therapy eradicated U. parvum IAI from the amniotic fluid within 4 days. Placenta and fetal tissues were 90% culture negative at delivery. AZI therapy significantly delayed preterm delivery and prevented advanced fetal lung injury, although residual acute chorioamnionitis persisted. Conclusions Specific maternal antibiotic therapy can eradicate U. parvum from the amniotic fluid and key fetal organs, with subsequent prolongation of pregnancy which provides a therapeutic window of opportunity to effectively reduce the severity of fetal lung injury. PMID:23111115

Metabolism of azo dyes by human skin microbiota.

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Stingley, Robin L; Zou, Wen; Heinze, Thomas M; Chen, Huizhong; Cerniglia, Carl E

2010-01-01

Reduction of Methyl Red (MR) and Orange II (Or II) by 26 human skin bacterial species was monitored by a rapid spectrophotometric assay. The analysis indicated that skin bacteria, representing the genera Staphylococcus, Corynebacterium, Micrococcus, Dermacoccus and Kocuria, were able to reduce MR by 74-100 % in 24 h, with only three species unable to reduce completely the dye in that time. Among the species tested, only Corynebacterium xerosis was unable to reduce Or II to any degree by 24 h, and only Staphylococcus delphini, Staphylococcus sciuri subsp. sciuri and Pseudomonas aeruginosa were able to reduce completely this dye within 24 h. MR reduction started with early-exponential growth in Staphylococcus aureus and Staphylococcus epidermidis, and around late-exponential/early-stationary growth in P. aeruginosa. Reduction of Or II, Ponceau S and Ponceau BS started during late-exponential/early-stationary growth for all three species. Using liquid chromatography/electrospray ionization mass spectrometry analyses, MR metabolites produced by Staph. aureus, Staph. epidermidis and P. aeruginosa were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid. Searches of available genomic and proteomic data revealed that at least four of the staphylococci in this study, Staphylococcus haemolyticus, Staph. epidermidis, Staphylococcus cohnii and Staphylococcus saprophyticus, have hypothetical genes with 77, 76, 75 and 74 % sequence identity to azo1 encoding an azoreductase from Staph. aureus and hypothetical proteins with 82, 80, 72 and 74 % identity to Azo1, respectively. In addition, Staphylococcus capitis has a protein with 79 % identity to Azo1. Western analysis detected proteins similar to Azo1 in all the staphylococci tested, except Staph. delphini, Staph. sciuri subsp. sciuri and Staphylococcus auricularis. The data presented in this report will be useful in the risk assessment process for evaluation of public exposure to products containing these dyes.

Effect of biosurfactant and fertilizer on biodegradation of crude oil by marine isolates of Bacillus megaterium, Corynebacterium kutscheri and Pseudomonas aeruginosa.

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Thavasi, Rengathavasi; Jayalakshmi, Singaram; Banat, Ibrahim M

2011-01-01

This study was conducted to investigate the effects of fertilizers and biosurfactants on biodegradation of crude oil by three marine bacterial isolates; Bacillus megaterium, Corynebacterium kutscheri and Pseudomonas aeruginosa. Five sets of experiments were carried out in shake flask and microcosm conditions with crude oil as follows: Set 1-only bacterial cells added (no fertilizer and biosurfactant), Set 2-with additional fertilizer only, Set 3-with additional biosurfactant only, Set 4-with added biosurfactant+fertilizer, Set 5-with no bacterial cells added (control), all the above experimental sets were incubated for 168 h. The biosurfactant+fertilizer added Set 4, resulted in maximum crude oil degradation within shake flask and microcosm conditions. Among the three bacterial isolates, P. aeruginosa and biosurfactant produced by this strain resulted in maximum crude oil degradation compared to the other two bacterial strains investigated. Interestingly, when biosurfactant and bacterial cells were used (Set 3), significant oil biodegradation activity occurred and the difference between this treatment and that in Set 4 with added fertilizer+biosurfactant were only 4-5% higher degradation level in shake flask and 3.2-7% in microcosm experiments for all three bacterial strains used. It is concluded that, biosurfactants alone capable of promoting biodegradation to a large extent without added fertilizers, which will reduce the cost of bioremediation process and minimizes the dilution or wash away problems encountered when water soluble fertilizers used during bioremediation of aquatic environments. Copyright © 2010 Elsevier Ltd. All rights reserved.

Transcriptome and Gene Ontology (GO) Enrichment Analysis Reveals Genes Involved in Biotin Metabolism That Affect L-Lysine Production in Corynebacterium glutamicum.

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Kim, Hong-Il; Kim, Jong-Hyeon; Park, Young-Jin

2016-03-09

Corynebacterium glutamicum is widely used for amino acid production. In the present study, 543 genes showed a significant change in their mRNA expression levels in L-lysine-producing C. glutamicum ATCC21300 than that in the wild-type C. glutamicum ATCC13032. Among these 543 differentially expressed genes (DEGs), 28 genes were up- or downregulated. In addition, 454 DEGs were functionally enriched and categorized based on BLAST sequence homologies and gene ontology (GO) annotations using the Blast2GO software. Interestingly, NCgl0071 (bioB, encoding biotin synthase) was expressed at levels ~20-fold higher in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain. Five other genes involved in biotin metabolism or transport--NCgl2515 (bioA, encoding adenosylmethionine-8-amino-7-oxononanoate aminotransferase), NCgl2516 (bioD, encoding dithiobiotin synthetase), NCgl1883, NCgl1884, and NCgl1885--were also expressed at significantly higher levels in the L-lysine-producing ATCC21300 strain than that in the wild-type ATCC13032 strain, which we determined using both next-generation RNA sequencing and quantitative real-time PCR analysis. When we disrupted the bioB gene in C. glutamicum ATCC21300, L-lysine production decreased by approximately 76%, and the three genes involved in biotin transport (NCgl1883, NCgl1884, and NCgl1885) were significantly downregulated. These results will be helpful to improve our understanding of C. glutamicum for industrial amino acid production.

The MurC ligase essential for peptidoglycan biosynthesis is regulated by the serine/threonine protein kinase PknA in Corynebacterium glutamicum.

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Fiuza, Maria; Canova, Marc J; Patin, Delphine; Letek, Michal; Zanella-Cléon, Isabelle; Becchi, Michel; Mateos, Luís M; Mengin-Lecreulx, Dominique; Molle, Virginie; Gil, José A

2008-12-26

The Mur ligases play an essential role in the biosynthesis of bacterial cell-wall peptidoglycan and thus represent attractive targets for the design of novel antibacterials. These enzymes catalyze the stepwise formation of the peptide moiety of the peptidoglycan disaccharide peptide monomer unit. MurC is responsible of the addition of the first residue (L-alanine) onto the nucleotide precursor UDP-MurNAc. Phosphorylation of proteins by Ser/Thr protein kinases has recently emerged as a major physiological mechanism of regulation in prokaryotes. Herein, the hypothesis of a phosphorylation-dependent mechanism of regulation of the MurC activity was investigated in Corynebacterium glutamicum. We showed that MurC was phosphorylated in vitro by the PknA protein kinase. An analysis of the phosphoamino acid content indicated that phosphorylation exclusively occurred on threonine residues. Six phosphoacceptor residues were identified by mass spectrometry analysis, and we confirmed that mutagenesis to alanine residues totally abolished PknA-dependent phosphorylation of MurC. In vitro and in vivo ligase activity assays showed that the catalytic activity of MurC was impaired following mutation of these threonine residues. Further in vitro assays revealed that the activity of the MurC-phosphorylated isoform was severely decreased compared with the non-phosphorylated protein. To our knowledge, this is the first demonstration of a MurC ligase phosphorylation in vitro. The finding that phosphorylation is correlated with a decrease in MurC enzymatic activity could have significant consequences in the regulation of peptidoglycan biosynthesis.

Increased Production of Food-Grade d-Tagatose from d-Galactose by Permeabilized and Immobilized Cells of Corynebacterium glutamicum, a GRAS Host, Expressing d-Galactose Isomerase from Geobacillus thermodenitrificans.

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Shin, Kyung-Chul; Sim, Dong-Hyun; Seo, Min-Ju; Oh, Deok-Kun

2016-11-02

The generally recognized as safe microorganism Corynebacterium glutamicum expressing Geobacillus thermodenitrificans d-galactose isomerase (d-GaI) was an efficient host for the production of d-tagatose, a functional sweetener. The d-tagatose production at 500 g/L d-galactose by the host was 1.4-fold higher than that by Escherichia coli expressing d-GaI. The d-tagatose-producing activity of permeabilized C. glutamicum (PCG) cells treated with 1% (w/v) Triton X-100 was 2.1-fold higher than that of untreated cells. Permeabilized and immobilized C. glutamicum (PICG) cells in 3% (w/v) alginate showed a 3.1-fold longer half-life at 50 °C and 3.1-fold higher total d-tagatose concentration in repeated batch reactions than PCG cells. PICG cells, which produced 165 g/L d-tagatose after 3 h, with a conversion of 55% (w/w) and a productivity of 55 g/L/h, showed significantly higher d-tagatose productivity than that reported for other cells. Thus, d-tagatose production by PICG cells may be an economical process to produce food-grade d-tagatose.

Occurrence of Cryptosporidium and Giardia in recycled waters used for irrigation and first description of Cryptosporidium parvum and C. muris in Greece.

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Spanakos, Gregory; Biba, Anastasia; Mavridou, Athena; Karanis, Panagiotis

2015-05-01

Here, we present the first time findings regarding the occurrence of Cryptosporidium and Giardia in sewage waters and the first molecular characterization of Cryptosporidium species in Greece. Biological treatment plants from three regions in Greece have been investigated. The detection of Cryptosporidium oocysts was by modified Ziehl-Neelsen acid fast (MZN-AF) and by immunofluorescence microscopy (IFT) for Cryptosporidium and Giardia (oo)cysts, whereas nested PCR based on the SSU rDNA assay was used for molecular detection of Cryptosporidium followed by sequencing for the genetic characterization of the species. In total, 73 samples (37 raw sewage samples and 38 of treated water samples) were collected and analyzed. Of the 73 water samples, 4 samples were Cryptosporidium-positive by IFT and staining, 12 samples were Cryptosporidium-positive by nested PCR; 9 samples were Giardia-positive by IFT. We showed that Cryptosporidium cysts are found both in the input and the discharge of the biological treatment plants. Molecular characterization of Cryptosporidium based on the small subunit ribosomal DNA gene resulted in the determination of Cryptosporidium parvum and Cryptosporidium muris Greek isolates. This is the first report of Cryptosporidium and Giardia occurrence in wastewaters and the first molecular identification of Cryptosporidium species in Greek environments. As the treated water is used for irrigation, or it is discharged into the sea, our findings indicate that biological treatment facilities constitute a possible risk for public health because the related species are prevalent in humans; the results invite for further epidemiological investigations to evaluate the real public health risk in Greece.

Physicochemical properties of 3,4,5-trimethoxybenzoates of Mn(II, Co(II, Ni(II and Zn(II

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W. FERENC

2005-09-01

Full Text Available The complexes of Mn(II, Co(II, Ni(II, Cu(II and Zn(II with 3,4,5-trimethoxybenzoic acid anion of the formula: M(C10H11O52·nH2O, where n = 6 for Ni(II, n = 1 for Mn(II, Co(II, Cu(II, and n = 0 for Zn, have been synthesized and characterized by elemental analysis, IR spectroscopy, X–ray diffraction measurements, thermogravimetry and magnetic studies. They are crystalline compounds characterized by various symmetry. They decompose in various ways when heated in air to 1273 K. At first, they dehydrate in one step and form anhydrous salts. The final products of decomposition are oxides of the respective metals (Mn2O3, Co3O4, NiO, CuO, ZnO. The solubilities of the analysed complexes in water at 293 K are in the orders of 10-2 – 10-4 mol dm-3. The magnetic susceptibilities of the Mn(II, Co(II, Ni(II and Cu(II complexes were measured over the range of 76–303 K and the magnetic moments were calculated. The results show that the 3,4,5-trimethoxybenzoates of Mn(II, Co(II and Ni(II are high-spin complexes but that of Cu(II forms a dimer [Cu2(C10H11O54(H2O2]. The carboxylate groups bind as monodentate or bidentate chelating or bridging ligands.

Bioconversion of Gibberellin Fermentation Residue into Feed Supplement and Organic Fertilizer Employing Housefly (Musca domestica L. Assisted by Corynebacterium variabile.

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Sen Yang

Full Text Available The accumulation of a considerable quantity of gibberellin fermentation residue (GFR during gibberellic acid A3 (GA3 production not only results in the waste of many resources, but also poses a potential hazard to the environment, indicating that the safe treatment of GFR has become an urgent issue for GA3 industry. The key to recycle GFR is converting it into an available resource and removing the GA3 residue. To this end, we established a co-bioconversion process in this study using house fly larvae (HFL and microbes (Corynebacterium variabile to convert GFR into insect biomass and organic fertilizer. About 85.5% GA3 in the GFR was removed under the following optimized solid-state fermentation conditions: 60% GFR, 40% rice straw powder, pH 8.5 and 6 days at 26 °C. A total of 371 g housefly larvae meal and 2,064 g digested residue were bio-converted from 3,500 g raw GFR mixture contaning1, 400 g rice straw in the unit of (calculated dry matter. HFL meal derived from GFR contained 56.4% protein, 21.6% fat, and several essential amino acids, suggesting that it is a potential alternative animal feed protein source. Additionally, the digested GFR could be utilized as an organic fertilizer with a content of 3.2% total nitrogen, 2.0% inorganic phosphorus, 1.3% potassium and 91.5% organic matter. This novel GFR bio-conversion method can mitigate potential environmental pollution and recycle the waste resources.

Bioconversion of Gibberellin Fermentation Residue into Feed Supplement and Organic Fertilizer Employing Housefly (Musca domestica L.) Assisted by Corynebacterium variabile

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Yang, Sen; Xie, Jiufeng; Hu, Nan; Liu, Yixiong; Zhang, Jiner; Ye, Xiaobin; Liu, Ziduo

2015-01-01

The accumulation of a considerable quantity of gibberellin fermentation residue (GFR) during gibberellic acid A3 (GA3) production not only results in the waste of many resources, but also poses a potential hazard to the environment, indicating that the safe treatment of GFR has become an urgent issue for GA3 industry. The key to recycle GFR is converting it into an available resource and removing the GA3 residue. To this end, we established a co-bioconversion process in this study using house fly larvae (HFL) and microbes (Corynebacterium variabile) to convert GFR into insect biomass and organic fertilizer. About 85.5% GA3 in the GFR was removed under the following optimized solid-state fermentation conditions: 60% GFR, 40% rice straw powder, pH 8.5 and 6 days at 26°C. A total of 371g housefly larvae meal and 2,064g digested residue were bio-converted from 3,500g raw GFR mixture contaning1, 400g rice straw in the unit of (calculated) dry matter. HFL meal derived from GFR contained 56.4% protein, 21.6% fat, and several essential amino acids, suggesting that it is a potential alternative animal feed protein source. Additionally, the digested GFR could be utilized as an organic fertilizer with a content of 3.2% total nitrogen, 2.0% inorganic phosphorus, 1.3% potassium and 91.5% organic matter. This novel GFR bio-conversion method can mitigate potential environmental pollution and recycle the waste resources. PMID:25992605

Enhancement of γ-aminobutyric acid production in recombinant Corynebacterium glutamicum by co-expressing two glutamate decarboxylase genes from Lactobacillus brevis.

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Shi, Feng; Jiang, Junjun; Li, Yongfu; Li, Youxin; Xie, Yilong

2013-11-01

γ-Aminobutyric acid (GABA), a non-protein amino acid, is a bioactive component in the food, feed and pharmaceutical fields. To establish an effective single-step production system for GABA, a recombinant Corynebacterium glutamicum strain co-expressing two glutamate decarboxylase (GAD) genes (gadB1 and gadB2) derived from Lactobacillus brevis Lb85 was constructed. Compared with the GABA production of the gadB1 or gadB2 single-expressing strains, GABA production by the gadB1-gadB2 co-expressing strain increased more than twofold. By optimising urea supplementation, the total production of L-glutamate and GABA increased from 22.57 ± 1.24 to 30.18 ± 1.33 g L⁻¹, and GABA production increased from 4.02 ± 0.95 to 18.66 ± 2.11 g L⁻¹ after 84-h cultivation. Under optimal urea supplementation, L-glutamate continued to be consumed, GABA continued to accumulate after 36 h of fermentation, and the pH level fluctuated. GABA production increased to a maximum level of 27.13 ± 0.54 g L⁻¹ after 120-h flask cultivation and 26.32 g L⁻¹ after 60-h fed-batch fermentation. The conversion ratio of L-glutamate to GABA reached 0.60-0.74 mol mol⁻¹. By co-expressing gadB1 and gadB2 and optimising the urea addition method, C. glutamicum was genetically improved for de novo biosynthesis of GABA from its own accumulated L-glutamate.

A role of the transcriptional regulator LldR (NCgl2814) in glutamate metabolism under biotin-limited conditions in Corynebacterium glutamicum.

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Supkulsutra, Tanyanut; Maeda, Tomoya; Kumagai, Kosuke; Wachi, Masaaki

2013-01-01

Corynebacterium glutamicum is a Gram-positive, rod-shaped, aerobic bacterium used for the fermentative production of L-glutamate. LldR (NCgl2814) is known as a repressor for ldhA and lldD encoding lactate dehydrogenases. LdhA is responsible for production of L-lactate, while LldD is for its assimilation. Since L-lactate production was observed as a by-product of glutamate production under biotin-limited conditions, LldR might play a regulatory role in the glutamate metabolism. Here for the first time, we investigated effects of overproduction or deletion of LldR on the glutamate metabolism under biotin-limited conditions in C. glutamicum. It was found that glutamate production under biotin-limited conditions was decreased by overproduction of LldR. In the wild-type cells, L-lactate was produced in the first 24 h and it was re-consumed thereafter. On the other hand, in the overproduced cells, L-lactate was produced like the wild type, but it was not re-consumed. This means that L-lactate assimilation, which is catalyzed by LldD, was suppressed by the overproduction of LldR, but L-lactate production, which is catalyzed by LdhA, was not affected, indicating that LldR mainly controls the expression of lldD but not of ldhA under biotin-limited conditions. This was confirmed by quantitative real-time RT-PCR. From these results, it is suggested that L-lactate metabolism, which is controlled by LldR, has a buffering function of the pyruvate pool for glutamate production.

Rational modification of Corynebacterium glutamicum dihydrodipicolinate reductase to switch the nucleotide-cofactor specificity for increasing l-lysine production.

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Xu, Jian-Zhong; Yang, Han-Kun; Liu, Li-Ming; Wang, Ying-Yu; Zhang, Wei-Guo

2018-03-25

l-lysine is an important amino acid in animals and humans and NADPH is a vital cofactor for maximizing the efficiency of l-lysine fermentation. Dihydrodipicolinate reductase (DHDPR), an NAD(P)H-dependent enzyme, shows a variance in nucleotide-cofactor affinity in bacteria. In this study, we rationally engineered Corynebacterium glutamicum DHDPR (CgDHDPR) to switch its nucleotide-cofactor specificity resulting in an increase in final titer (from 82.6 to 117.3 g L -1 ), carbon yield (from 0.35 to 0.44 g [g glucose] -1 ) and productivity (from 2.07 to 2.93 g L -1  hr -1 ) of l-lysine in JL-6 ΔdapB::Ec-dapB C115G,G116C in fed-batch fermentation. To do this, we comparatively analyzed the characteristics of CgDHDPR and Escherichia coli DHDPR (EcDHDPR), indicating that hetero-expression of NADH-dependent EcDHDPR increased l-lysine production. Subsequently, we rationally modified the conserved structure of cofactor-binding motif, and results indicated that introducing the mutation K11A or R13A in CgDHDPR and introducing the mutation R16A or R39A in EcDHDPR modifies the nucleotide-cofactor affinity of DHDPR. Lastly, the effects of these mutated DHDPRs on l-lysine production were investigated. The highest increase (26.2%) in l-lysine production was observed for JL-6 ΔdapB::Ec-dapB C115G,G116C , followed by JL-6 Cg-dapB C37G,G38C (21.4%) and JL-6 ΔdapB::Ec-dapB C46G,G47C (15.2%). This is the first report of a rational modification of DHDPR that enhances the l-lysine production and yield through the modulation of nucleotide-cofactor specificity. © 2018 Wiley Periodicals, Inc.

Synthesis and spectral studies of manganese(II), cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II) and mercury(II) complexes of 4-oxo-4H-1-benzopyran-3-carboxaldehyde hydrazone derivatives

International Nuclear Information System (INIS)

Nawar, N.; Khattab, M.A.; Bekheit, M.M.; El-Kaddah, A.H.

1996-01-01

A few complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) with 4-oxo-4H-1-benzopyran-3-(carboxaldehyde-4-chlorobenzylhydrazone) (BCBH) and 4-oxo-4H-1-benzopyran-3-(carboxaldehyde-4-methylbenzylhydrazone) (BMBH) have been synthesised and characterized by elemental analysis, molar conductivities, magnetic measurements and infrared (IR) and visible spectral studies. The IR spectra show that BCBH and BMBH behave as bidentate ligands either in the keto or enol form. (author). 24 refs., 2 tabs

Synthesis, Characterization, and Biological Activity of Mn(II, Fe(II, Co(II, Ni(II, Cu(II, Zn(II, and Cd(II Complexes of N-Thiophenoyl-N′-Phenylthiocarbohydrazide

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M. Yadav

2013-01-01

Full Text Available Mn(II, Fe(II, Co(II, Ni(II, Cu(II, Zn(II, and Cd(II complex of N-thiophenoyl -N′-phenylthiocarbohydrazide (H2 TPTH have been synthesized and characterized by elemental analysis, magnetic susceptibility measurements, infrared, NMR, electronic, and ESR spectral studies. The complexes were found to have compositions [Mn(H TPTH2], [Co(TPTH (H2O2], [Ni(TPTH (H2O2], [Cu(TPTH], [Zn(H TPTH], [Cd(H TPTH2], and [Fe(H TPTH2(EtOH]. The magnetic and electronic spectral studies suggest square planar geometry for [Cu(TPTH], tetrahedral geometry for [Zn(TPTH] and [Cd(H TPTH2], and octahedral geometry for rest of the complexes. The infrared spectral studies of the 1 : 1 deprotonated complexes suggest bonding through enolic oxygen, thiolato sulfur, and both the hydrazinic nitrogens. Thus, H2TPTH acts as a binegative tetradentate ligand. H2 TPTH and its metal complexes have been screened against several bacteria and fungi.

BIALLELIC POLYMORPHISM IN THE INTRON REGION OF B-TUBULIN GENE OF CRYPTOSPORIDIUM PARASITES

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Nucleotide sequencing of polymerase chain reaction-amplified intron region of the Cryptosporidium parvum B-tubulin gene in 26 human and 15 animal isolates revealed distinct genetic polymorphism between the human and bovine genotypes. The separation of 2 genotypes of C. parvum is...

Effect of immunomodulation on the fate of tumor cells in the central nervous system and systemic organs of mice. Distribution of [125I]5-iodo-2'-deoxyuridine-labeled KHT tumor cells after left intracardial injection

International Nuclear Information System (INIS)

Conley, F.K.

1982-01-01

The effect of systemic immunomodulation on tumor cell arrest and retention in the central nervous system was studied by following radioactively labeled tumor cells. KHT mouse sarcoma tumor cells were labeled in vitro with [ 125 I]IdUrd, and 1x10 5 tumor cells were injected into the left side of the hearts of syngeneic C3H mice. Experimental groups consisted of untreated normal mice, mice pretreated iv with Corynebacterium parvum, and mice chronically infected with Toxoplasma gondii; in this model both groups of immunomodulated mice are protected from developing systemic metastatic tumor, but only Toxoplasma-infected mice have protection against metastatic brain tumor. At time intervals from 1 to 96 hours, groups of mice from each experimental group were killed, and the brain and other organs were monitored for radioactivity to determine the number of viable tumor cells that had been present at the time of death. Normal mice demonstrated significant retention of tumor cells in the brain and kidneys plus adrenals at 96 hours. By contrast, in both groups of immunomodulated mice tumor cells were rapidly eliminated from systemic organs, but tumor cells were significantly retained in the central nervous system even at 96 hours after tumor cell injections. The results indicated that generalized immunomodulation had more effect in elimination of tumor cells from systemic organs than from the brain and that the elimination of tumor cells from the brain in Toxoplasma-infected mice was a delayed phenomenon

Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II binary complexes of l-methionine in 1,2-propanediol-water mixtures

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M. Padma Latha

2007-04-01

Full Text Available Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-methionine in 0.0-60 % v/v 1,2-propanediol-water mixtures maintaining an ionic strength of 0.16 M at 303 K has been studied pH metrically. The active forms of ligand are LH2+, LH and L-. The predominant species detected are ML, MLH, ML2, ML2H, ML2H2 and MLOH. Models containing different numbers of species were refined by using the computer program MINIQUAD 75. The best-fit chemical models were arrived at based on statistical parameters. The trend in variation of complex stability constants with change in the dielectric constant of the medium is explained on the basis of electrostatic and non-electrostatic forces.

High bacterial loads of Ureaplasma may be associated with non-specific cervicitis.

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Liu, Lu; Cao, Guojun; Zhao, Zhen; Zhao, Fang; Huang, Yanqun

2014-09-01

Ureaplasma parvum and Ureaplasma urealyticum are commonly found in the cervix of women with non-chlamydial and non-gonococcal cervicitis or non-specific cervicitis (NSC). However their contribution to the aetiology of NSC is controversial. U. parvum and U. urealyticum were identified and quantified in cervical swabs collected from 155 women with NSC and 312 controls without NSC, using real-time PCR. The relative bacterial quantification was then calculated using the Ureaplasma copy number divided by the number of host cells; this is important for the correction of bias linked to the number of cells harvested in different swabs. Ureaplasma was detected in 58.7% (91/155) of NSC patients: U. parvum in 30.3%, U. urealyticum in 16.1%, and mixed infection in 12.3%. It was also detected in 54.5% (170/312) of controls: U. parvum in 33.0%, U. urealyticum in 11.5%, and mixed infection in 9.9%. There were no significant differences for U. parvum, U. urealyticum, or mixed infection between the 2 groups (p > 0.05). However, both biovars were present at higher concentrations in NSC patients than in controls (p 10 copies/1000 cells as a reference, the positive rate of U. parvum in NSC patients was 16.1%, significantly higher than that in controls at 5.1% (relative risk 3.145, p Ureaplasma can adhere to host cells, colonize, internalize, and subsequently produce pathological lesions. A high density of Ureaplasma in the cervix may be associated with the aetiology of NSC.

cobalt (ii), nickel (ii)

African Journals Online (AJOL)

DR. AMINU

Department of Chemistry Bayero University, P. M. B. 3011, Kano, Nigeria. E-mail: hnuhu2000@yahoo.com. ABSTRACT. The manganese (II), cobalt (II), nickel (II) and .... water and common organic solvents, but are readily soluble in acetone. The molar conductance measurement [Table 3] of the complex compounds in.

Disinfection technology with ozone for cryptosporidium; Cryptosporidium taisaku to shite no ozone shodoku gijutsu

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Y.; Takahashi, K. [Fuji Electric Co. Ltd., Tokyo (Japan); Motoyama, N. [Fuji Electric Corporate Research and Development, Ltd., Kanagawa (Japan)

1998-06-10

Measures against Cryptosporidium parvum (C. parvum) in the waterworks are discussed. C. parvum is a pathogenic protozoan, and exists in the form of oocyst protected by a hard shell. It does not multiply in water or food, but does in human intestines and causes violent diarrhea and bellyache. A grave concern was created when many people were infected with the protozoan via tap water in Japan and the United States. Under such circumstances, ozone is used in an experiment to inactivate C. parvum. It is found that the C. parvum oocyst inactivation effect is evaluated by using a Ct value (disinfectant concentration Cmg/Ltimescontact time in minute) and that ozone treatment inactivates 90-99% of the protozoan. When various advanced water treatment technologies are being introduced for the purpose of serving safe and tasty water, the outcome of this study conveniently offers an ozone treatment method that will additionally inactivate pathogenic protozoa. Studies will be continued to elucidate the effects of factors of ozone treatment and water quality for the completion of an ideal disinfection process. Reference is made to an example of disinfection work implemented at a water purification plant of Milwaukie City, United States. 9 refs., 6 figs., 4 tabs.

CysQ of , a Protozoa, May Have Been Acquired from Bacteria by Horizontal Gene Transfer

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Ji Young Lee

2012-03-01

Full Text Available Horizontal gene transfer (HGT is the movement of genetic material between kingdoms and is considered to play a positive role in adaptation. Cryptosporidium parvum is a parasitic protozoan that causes an infectious disease. Its genome sequencing reported 14 bacteria-like proteins in the nuclear genome. Among them, cgd2_1810, which has been annotated as CysQ, a sulfite synthesis pathway protein, is listed as one of the candidates of genes horizontally transferred from bacterial origin. In this report, we examined this issue using phylogenetic analysis. Our BLAST search showed that C. parvum CysQ protein had the highest similarity with that of proteobacteria. Analysis with NCBI's Conserved Domain Tree showed phylogenetic incongruence, in that C. parvum CysQ protein was located within a branch of proteobacteria in the cd01638 domain, a bacterial member of the inositol monophosphatase family. According to Kyoto Encyclopedia of Genes and Genomes (KEGG pathway, the sulfate assimilation pathway, where CysQ plays an important role, is well conserved in most eukaryotes as well as prokaryotes. However, the Apicomplexa, including C. parvum, largely lack orthologous genes of the pathway, suggesting its loss in those protozoan lineages. Therefore, we conclude that C. parvum regained cysQ from proteobacteria by HGT, although its functional role is elusive.

The transcriptional regulatory network of Corynebacterium jeikeium K411 and its interaction with metabolic routes contributing to human body odor formation.

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Barzantny, Helena; Schröder, Jasmin; Strotmeier, Jasmin; Fredrich, Eugenie; Brune, Iris; Tauch, Andreas

2012-06-15

Lipophilic corynebacteria are involved in the generation of volatile odorous products in the process of human body odor formation by degrading skin lipids and specific odor precursors. Therefore, these bacteria represent appropriate model systems for the cosmetic industry to examine axillary malodor formation on the molecular level. To understand the transcriptional control of metabolic pathways involved in this process, the transcriptional regulatory network of the lipophilic axilla isolate Corynebacterium jeikeium K411 was reconstructed from the complete genome sequence. This bioinformatic approach detected a gene-regulatory repertoire of 83 candidate proteins, including 56 DNA-binding transcriptional regulators, nine two-component systems, nine sigma factors, and nine regulators with diverse physiological functions. Furthermore, a cross-genome comparison among selected corynebacterial species of the taxonomic cluster 3 revealed a common gene-regulatory repertoire of 44 transcriptional regulators, including the MarR-like regulator Jk0257, which is exclusively encoded in the genomes of this taxonomical subline. The current network reconstruction comprises 48 transcriptional regulators and 674 gene-regulatory interactions that were assigned to five interconnected functional modules. Most genes involved in lipid degradation are under the combined control of the global cAMP-sensing transcriptional regulator GlxR and the LuxR-family regulator RamA, probably reflecting the essential role of lipid degradation in C. jeikeium. This study provides the first genome-scale in silico analysis of the transcriptional regulation of metabolism in a lipophilic bacterium involved in the formation of human body odor. Copyright © 2012 Elsevier B.V. All rights reserved.

The MurC Ligase Essential for Peptidoglycan Biosynthesis Is Regulated by the Serine/Threonine Protein Kinase PknA in Corynebacterium glutamicum*

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Fiuza, Maria; Canova, Marc J.; Patin, Delphine; Letek, Michal; Zanella-Cléon, Isabelle; Becchi, Michel; Mateos, Luís M.; Mengin-Lecreulx, Dominique; Molle, Virginie; Gil, José A.

2008-01-01

The Mur ligases play an essential role in the biosynthesis of bacterial cell-wall peptidoglycan and thus represent attractive targets for the design of novel antibacterials. These enzymes catalyze the stepwise formation of the peptide moiety of the peptidoglycan disaccharide peptide monomer unit. MurC is responsible of the addition of the first residue (l-alanine) onto the nucleotide precursor UDP-MurNAc. Phosphorylation of proteins by Ser/Thr protein kinases has recently emerged as a major physiological mechanism of regulation in prokaryotes. Herein, the hypothesis of a phosphorylation-dependent mechanism of regulation of the MurC activity was investigated in Corynebacterium glutamicum. We showed that MurC was phosphorylated in vitro by the PknA protein kinase. An analysis of the phosphoamino acid content indicated that phosphorylation exclusively occurred on threonine residues. Six phosphoacceptor residues were identified by mass spectrometry analysis, and we confirmed that mutagenesis to alanine residues totally abolished PknA-dependent phosphorylation of MurC. In vitro and in vivo ligase activity assays showed that the catalytic activity of MurC was impaired following mutation of these threonine residues. Further in vitro assays revealed that the activity of the MurC-phosphorylated isoform was severely decreased compared with the non-phosphorylated protein. To our knowledge, this is the first demonstration of a MurC ligase phosphorylation in vitro. The finding that phosphorylation is correlated with a decrease in MurC enzymatic activity could have significant consequences in the regulation of peptidoglycan biosynthesis. PMID:18974047

Rapid hybrid de novo assembly of a microbial genome using only short reads: Corynebacterium pseudotuberculosis I19 as a case study.

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Cerdeira, Louise Teixeira; Carneiro, Adriana Ribeiro; Ramos, Rommel Thiago Jucá; de Almeida, Sintia Silva; D'Afonseca, Vivian; Schneider, Maria Paula Cruz; Baumbach, Jan; Tauch, Andreas; McCulloch, John Anthony; Azevedo, Vasco Ariston Carvalho; Silva, Artur

2011-08-01

Due to the advent of the so-called Next-Generation Sequencing (NGS) technologies the amount of monetary and temporal resources for whole-genome sequencing has been reduced by several orders of magnitude. Sequence reads can be assembled either by anchoring them directly onto an available reference genome (classical reference assembly), or can be concatenated by overlap (de novo assembly). The latter strategy is preferable because it tends to maintain the architecture of the genome sequence the however, depending on the NGS platform used, the shortness of read lengths cause tremendous problems the in the subsequent genome assembly phase, impeding closing of the entire genome sequence. To address the problem, we developed a multi-pronged hybrid de novo strategy combining De Bruijn graph and Overlap-Layout-Consensus methods, which was used to assemble from short reads the entire genome of Corynebacterium pseudotuberculosis strain I19, a bacterium with immense importance in veterinary medicine that causes Caseous Lymphadenitis in ruminants, principally ovines and caprines. Briefly, contigs were assembled de novo from the short reads and were only oriented using a reference genome by anchoring. Remaining gaps were closed using iterative anchoring of short reads by craning to gap flanks. Finally, we compare the genome sequence assembled using our hybrid strategy to a classical reference assembly using the same data as input and show that with the availability of a reference genome, it pays off to use the hybrid de novo strategy, rather than a classical reference assembly, because more genome sequences are preserved using the former. Copyright © 2011 Elsevier B.V. All rights reserved.

Identification of Cryptosporidium Species in Fish from Lake Geneva (Lac Léman) in France.

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Certad, Gabriela; Dupouy-Camet, Jean; Gantois, Nausicaa; Hammouma-Ghelboun, Ourida; Pottier, Muriel; Guyot, Karine; Benamrouz, Sadia; Osman, Marwan; Delaire, Baptiste; Creusy, Colette; Viscogliosi, Eric; Dei-Cas, Eduardo; Aliouat-Denis, Cecile Marie; Follet, Jérôme

2015-01-01

Cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. However, little data are available regarding the identification of Cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. To evaluate the prevalence of Cryptosporidiumspp. in fish from Lake Geneva (Lac Léman) in France, 41 entire fish and 100 fillets (cuts of fish flesh) were collected from fishery suppliers around the lake. Nested PCR using degenerate primers followed by sequence analysis was used. Five fish species were identified as potential hosts of Cryptosporidium: Salvelinus alpinus, Esox lucius, Coregonus lavaretus, Perca fluviatilis, and Rutilus rutilus. The presence of Cryptosporidium spp. was found in 15 out of 41 fish (37%), distributed as follows: 13 (87%) C. parvum, 1 (7%) C. molnari, and 1 (7%) mixed infection (C. parvum and C. molnari). C. molnari was identified in the stomach, while C. parvum was found in the stomach and intestine. C. molnari was also detected in 1 out of 100 analyzed fillets. In order to identify Cryptosporidium subtypes, sequencing of the highly polymorphic 60-kDa glycoprotein (gp60) was performed. Among the C. parvum positive samples, three gp60 subtypes were identified: IIaA15G2R1, IIaA16G2R1, and IIaA17G2R1. Histological examination confirmed the presence of potential developmental stages of C. parvum within digestive epithelial cells. These observations suggest that C. parvum is infecting fish, rather than being passively carried. Since C. parvum is a zoonotic species, fish potentially contaminated by the same subtypes found in terrestrial mammals would be an additional source of infection for humans and animals, and may also contribute to the contamination of the environment with this parasite. Moreover, the risk of human transmission is strengthened by the

Identification of Cryptosporidium Species in Fish from Lake Geneva (Lac Léman in France.

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Gabriela Certad

Full Text Available Cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. However, little data are available regarding the identification of Cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. To evaluate the prevalence of Cryptosporidiumspp. in fish from Lake Geneva (Lac Léman in France, 41 entire fish and 100 fillets (cuts of fish flesh were collected from fishery suppliers around the lake. Nested PCR using degenerate primers followed by sequence analysis was used. Five fish species were identified as potential hosts of Cryptosporidium: Salvelinus alpinus, Esox lucius, Coregonus lavaretus, Perca fluviatilis, and Rutilus rutilus. The presence of Cryptosporidium spp. was found in 15 out of 41 fish (37%, distributed as follows: 13 (87% C. parvum, 1 (7% C. molnari, and 1 (7% mixed infection (C. parvum and C. molnari. C. molnari was identified in the stomach, while C. parvum was found in the stomach and intestine. C. molnari was also detected in 1 out of 100 analyzed fillets. In order to identify Cryptosporidium subtypes, sequencing of the highly polymorphic 60-kDa glycoprotein (gp60 was performed. Among the C. parvum positive samples, three gp60 subtypes were identified: IIaA15G2R1, IIaA16G2R1, and IIaA17G2R1. Histological examination confirmed the presence of potential developmental stages of C. parvum within digestive epithelial cells. These observations suggest that C. parvum is infecting fish, rather than being passively carried. Since C. parvum is a zoonotic species, fish potentially contaminated by the same subtypes found in terrestrial mammals would be an additional source of infection for humans and animals, and may also contribute to the contamination of the environment with this parasite. Moreover, the risk of human transmission is strengthened by

The Role of the Multiple Banded Antigen of Ureaplasma parvum in Intra-Amniotic Infection: Major Virulence Factor or Decoy?

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Dando, Samantha J.; Nitsos, Ilias; Kallapur, Suhas G.; Newnham, John P.; Polglase, Graeme R.; Pillow, J. Jane; Jobe, Alan H.; Timms, Peter; Knox, Christine L.

2012-01-01

The multiple banded antigen (MBA) is a predicted virulence factor of Ureaplasma species. Antigenic variation of the MBA is a potential mechanism by which ureaplasmas avoid immune recognition and cause chronic infections of the upper genital tract of pregnant women. We tested whether the MBA is involved in the pathogenesis of intra-amniotic infection and chorioamnionitis by injecting virulent or avirulent-derived ureaplasma clones (expressing single MBA variants) into the amniotic fluid of pregnant sheep. At 55 days of gestation pregnant ewes (n = 20) received intra-amniotic injections of virulent-derived or avirulent-derived U. parvum serovar 6 strains (2×104 CFU), or 10B medium (n = 5). Amniotic fluid was collected every two weeks post-infection and fetal tissues were collected at the time of surgical delivery of the fetus (140 days of gestation). Whilst chronic colonisation was established in the amniotic fluid of animals infected with avirulent-derived and virulent-derived ureaplasmas, the severity of chorioamnionitis and fetal inflammation was not different between these groups (p>0.05). MBA size variants (32–170 kDa) were generated in vivo in amniotic fluid samples from both the avirulent and virulent groups, whereas in vitro antibody selection experiments led to the emergence of MBA-negative escape variants in both strains. Anti-ureaplasma IgG antibodies were detected in the maternal serum of animals from the avirulent (40%) and virulent (55%) groups, and these antibodies correlated with increased IL-1β, IL-6 and IL-8 expression in chorioamnion tissue (pureaplasmas are capable of MBA phase variation in vitro; however, ureaplasmas undergo MBA size variation in vivo, to potentially prevent eradication by the immune response. Size variation of the MBA did not correlate with the severity of chorioamnionitis. Nonetheless, the correlation between a maternal humoral response and the expression of chorioamnion cytokines is a novel finding. This host

An 8-month history of meningitis in an extremely low birth weight infant? - Long-lasting Infection with Ureaplasma parvum.

Science.gov (United States)

Glaser, K; Wohlleben, M; Speer, C P

2015-02-01

Ureaplasma spp. have been implicated in the pathogenesis of both preterm labor and neonatal morbidity including pneumonia and sepsis and the development of chronic lung disease of prematurity. Data on Ureaplasma meningitis are limited and partly controversially discussed. We report the unique case of a 9-month-old infant with progressive internal hydrocephalus of unknown origin and developmental delay due to a history of>200 days of inflammation of the central nervous system. The female extremely low birth weight infant had been referred to our hospital for ventriculoperitoneal shunt implantation. She had been born at 26+3 weeks of gestation with a birth weight of 940 g. With the exception of a moderate respiratory distress syndrome, postnatal period had been reported uneventful. However, internal hydrocephalus had become manifest at 4 weeks of postnatal age. Intraventricular hemorrhage had not been documented by cranial ultrasound and magnetic resonance imaging. Cerebrospinal fluid (CSF) analysis had repetitively revealed pronounced inflammation reflected by pleocytosis (50-86 leukocytes/μL, 60% lymphocytes), CSF protein levels of 578-1,026 mg/dL and undetectable CSF glucose. Although suggesting bacterial meningitis, microbial diagnostics had not been indicative, and empirical antibiotics had not affected the CSF findings. On admission to our hospital, CSF analysis still documented significant inflammation (125 leukocytes/μL, CSF protein 565 mg/dL, CSF glucoseUreaplasma spp. and Mycoplasma hominis. U. parvum was detected in CSF by culture and PCR, no other pathogens were isolated. On intravenous treatment with chloramphenicol, CSF profile continuously normalized, and cultures and PCR became negative. Treatment was continued for 3 weeks, and the infant was discharged after uncomplicated ventriculoperitoneal shunt placement. During a 12-month observation period she has shown encouraging recovery. In preterm infants, in particular, internal hydrocephalus of

Impacts of golden alga Prymnesium parvum on fish populations in reservoirs of the upper Colorado River and Brazos River basins, Texas

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VanLandeghem, Matthew M.; Farooqi, Mukhtar; Farquhar, B.; Patino, Reynaldo

2013-01-01

Several reservoirs in the upper Colorado River and Brazos River basins in Texas have experienced toxic blooms of golden alga Prymnesium parvum and associated fish kills since 2001. There is a paucity of information, however, regarding the population-level effects of such kills in large reservoirs, species-specific resistance to or recovery from kills, or potential differences in the patterns of impacts among basins. We used multiple before-after, control-impact analysis to determine whether repeated golden alga blooms have led to declines in the relative abundance and size structure of fish populations. Sustained declines were noted for 9 of 12 fish species surveyed in the upper Colorado River, whereas only one of eight species was impacted by golden alga in the Brazos River. In the upper Colorado River, White Bass Morone chrysops, White Crappie Pomoxis annularis, Largemouth Bass Micropterus salmoides, Bluegill Lepomis macrochirus, River Carpsucker Carpiodes carpio, Freshwater Drum Aplodinotus grunniens, Channel Catfish Ictalurus punctatus, Flathead Catfish Pylodictis olivaris, and Blue Catfish I. furcatus exhibited sustained declines in relative abundance, size structure, or both; Gizzard Shad Dorosoma cepedianum, Longnose Gar Lepisosteus osseus, and Common Carp Cyprinus carpio did not exhibit those declines. In the Brazos River, only the relative abundance of Blue Catfish was impacted. Overall, toxic golden alga blooms can negatively impact fish populations over the long-term, but the patterns of impact can vary considerably among river basins and species. In the Brazos River, populations of most fish species appear to be healthy, suggesting a positive angling outlook for this basin. In the upper Colorado River, fish populations have been severely impacted, and angling opportunities have been reduced. Basin-specific management plans aimed at improving water quality and quantity will likely reduce bloom intensity and allow recovery of fish populations to the

Overexpression of Genes Encoding Glycolytic Enzymes in Corynebacterium glutamicum Enhances Glucose Metabolism and Alanine Production under Oxygen Deprivation Conditions

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Yamamoto, Shogo; Gunji, Wataru; Suzuki, Hiroaki; Toda, Hiroshi; Suda, Masako; Jojima, Toru; Inui, Masayuki

2012-01-01

We previously reported that Corynebacterium glutamicum strain ΔldhAΔppc+alaD+gapA, overexpressing glyceraldehyde-3-phosphate dehydrogenase-encoding gapA, shows significantly improved glucose consumption and alanine formation under oxygen deprivation conditions (T. Jojima, M. Fujii, E. Mori, M. Inui, and H. Yukawa, Appl. Microbiol. Biotechnol. 87:159–165, 2010). In this study, we employ stepwise overexpression and chromosomal integration of a total of four genes encoding glycolytic enzymes (herein referred to as glycolytic genes) to demonstrate further successive improvements in C. glutamicum glucose metabolism under oxygen deprivation. In addition to gapA, overexpressing pyruvate kinase-encoding pyk and phosphofructokinase-encoding pfk enabled strain GLY2/pCRD500 to realize respective 13% and 20% improved rates of glucose consumption and alanine formation compared to GLY1/pCRD500. Subsequent overexpression of glucose-6-phosphate isomerase-encoding gpi in strain GLY3/pCRD500 further improved its glucose metabolism. Notably, both alanine productivity and yield increased after each overexpression step. After 48 h of incubation, GLY3/pCRD500 produced 2,430 mM alanine at a yield of 91.8%. This was 6.4-fold higher productivity than that of the wild-type strain. Intracellular metabolite analysis showed that gapA overexpression led to a decreased concentration of metabolites upstream of glyceraldehyde-3-phosphate dehydrogenase, suggesting that the overexpression resolved a bottleneck in glycolysis. Changing ratios of the extracellular metabolites by overexpression of glycolytic genes resulted in reduction of the intracellular NADH/NAD+ ratio, which also plays an important role on the improvement of glucose consumption. Enhanced alanine dehydrogenase activity using a high-copy-number plasmid further accelerated the overall alanine productivity. Increase in glycolytic enzyme activities is a promising approach to make drastic progress in growth-arrested bioprocesses. PMID

Cr(III,Mn(II,Fe(III,Co(II,Ni(II,Cu(II and Zn(II Complexes with Diisobutyldithiocarbamato Ligand

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Mohammad Tarique

2011-01-01

Full Text Available The synthesis of sulphur and nitrogen containing dithiocarbamato ligand derived from diisobutylamine as well as its coordination compounds with 3d series transition metals is presented. These synthesized compounds were characterized on the basis of elemental analysis, conductometric measurements and IR spectral studies. The analytical data showed the stoichiometry 1:2 and 1:3 for the compounds of the types ML2 {M=Mn(II, Co(II, Ni(II, Cu(II and Zn(II} and M'L3{M'=Cr(III and Fe(III} respectively. The conductometric measurements proved the non-electrolytic behaviour of all the compounds. The bidentate nature of dithiocarbamato moiety was confirmed on the basis of IR spectral data.

Computer augumented modelling studies of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-glutamic acid in 1,2-propanediol–water mixtures

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MAHESWARA RAO VEGI

2008-12-01

Full Text Available Chemical speciation of Pb(II, Cd(II, Hg(II, Co(II, Ni(II, Cu(II and Zn(II complexes of L-glutamic acid was studied at 303 K in 0–60 vol. % 1,2-propanediol–water mixtures, whereby the ionic strength was maintained at 0.16 mol dm-3. The active forms of the ligand are LH3+, LH2 and LH–. The predominant detected species were ML, ML2, MLH, ML2H and ML2H2. The trend of the variation in the stability constants with changing dielectric constant of the medium is explained based on the cation stabilizing nature of the co-solvents, specific solvent–water interactions, charge dispersion and specific interactions of the co-solvent with the solute. The effect of systematic errors in the concentrations of the substances on the stability constants is in the order alkali > > acid > ligand > metal. The bioavailability and transportation of metals are explained based on distribution diagrams and stability constants.

Antioxidant, electrochemical, thermal, antimicrobial and alkane oxidation properties of tridentate Schiff base ligands and their metal complexes

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Ceyhan, Gökhan; Çelik, Cumali; Uruş, Serhan; Demirtaş, İbrahim; Elmastaş, Mahfuz; Tümer, Mehmet

2011-10-01

In this study, two Schiff base ligands (HL 1 and HL 2) and their Cu(II), Co(II), Ni(II), Pd(II) and Ru(III) metal complexes were synthesized and characterized by the analytical and spectroscopic methods. Alkane oxidation activities of the metal complexes were studied on cyclohexane as substrate. The ligands and their metal complexes were evaluated for their antimicrobial activity against Corynebacterium xerosis, Bacillus brevis, Bacillus megaterium, Bacillus cereus, Mycobacterium smegmatis, Staphylococcus aureus, Micrococcus luteus and Enterococcus faecalis (as Gram-positive bacteria) and Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Yersinia enterocolitica, Klebsiella fragilis, Saccharomyces cerevisiae, and Candida albicans (as Gram-negative bacteria). The antioxidant properties of the Schiff base ligands were evaluated in a series of in vitro tests: 1,1-diphenyl-2-picrylhydrazyl (DPPH rad ) free radical scavenging and reducing power activity of superoxide anion radical generated non-enzymatic systems. Electrochemical and thermal properties of the compounds were investigated.

Effect of Polyhydroxybutyrate (PHB) storage on L-arginine production in recombinant Corynebacterium crenatum using coenzyme regulation.

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Xu, Meijuan; Qin, Jingru; Rao, Zhiming; You, Hengyi; Zhang, Xian; Yang, Taowei; Wang, Xiaoyuan; Xu, Zhenghong

2016-01-19

Corynebacterium crenatum SYPA 5 is the industrial strain for L-arginine production. Poly-β-hydroxybutyrate (PHB) is a kind of biopolymer stored as bacterial reserve materials for carbon and energy. The introduction of the PHB synthesis pathway into several strains can regulate the global metabolic pathway. In addition, both the pathways of PHB and L-arginine biosynthesis in the cells are NADPH-dependent. NAD kinase could upregulate the NADPH concentration in the bacteria. Thus, it is interesting to investigate how both PHB and NAD kinase affect the L-arginine biosynthesis in C. crenatum SYPA 5. C. crenatum P1 containing PHB synthesis pathway was constructed and cultivated in batch fermentation for 96 h. The enzyme activities of the key enzymes were enhanced comparing to the control strain C. crenatum SYPA 5. More PHB was found in C. crenatum P1, up to 12.7 % of the dry cell weight. Higher growth level and enhanced glucose consumptions were also observed in C. crenatum P1. With respect to the yield of L-arginine, it was 38.54 ± 0.81 g/L, increasing by 20.6 %, comparing to the control under the influence of PHB accumulation. For more NADPH supply, C. crenatum P2 was constructed with overexpression of NAD kinase based on C. crenatum P1. The NADPH concentration was increased in C. crenatum P2 comparing to the control. PHB content reached 15.7 % and 41.11 ± 1.21 g/L L-arginine was obtained in C. crenatum P2, increased by 28.6 %. The transcription levels of key L-arginine synthesis genes, argB, argC, argD and argJ in recombinant C. crenatum increased 1.9-3.0 times compared with the parent strain. Accumulation of PHB by introducing PHB synthesis pathway, together with up-regulation of coenzyme level by overexpressing NAD kinase, enables the recombinant C. crenatum to serve as high-efficiency cell factories in the long-time L-arginine fermentation. Furthermore, batch cultivation of the engineered C. crenatum revealed that it could accumulate both extracellular L

Synthesis and characterization of heterobimetallic complexes of the type [Cu(pn2][MCl4] where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II, and Hg(II

Directory of Open Access Journals (Sweden)

Seema Yadav

2016-11-01

Full Text Available A series of new bimetallic transition metal complexes of the type [Cu(pn2] [MCl4] have been synthesized (where M = Co(II, Ni(II, Cu(II, Zn(II, Cd(II and Hg(II, pn = 1,3-diaminopropane and characterized by elemental analysis, molar conductance, TGA, IR and electronic spectra. All the compounds are 1:1 electrolyte in DMF. The Cu(II ion is square-planar while metal ions in the anionic moiety acquire their usual tetrahedral arrangement. On the basis of these studies it is concluded that anionic moiety is electrically stabilized by its cationic counterpart.

Small Diameter Bomb Increment II (SDB II)

Science.gov (United States)

2015-12-01

Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-439 Small Diameter Bomb Increment II (SDB II) As of FY 2017 President’s Budget Defense... Bomb Increment II (SDB II) DoD Component Air Force Joint Participants Department of the Navy Responsible Office References SAR Baseline (Production...Mission and Description Small Diameter Bomb Increment II (SDB II) is a joint interest United States Air Force (USAF) and Department of the Navy

Synthesis and structural characterization of nickel(II), cobalt(II), Zinc(II), manganese(II), cadmium(II) and uranium(VI) complexes of α-oximinoacetoacet-o/p-anisidide thiosemicarbazone

International Nuclear Information System (INIS)

Patel, P.S.; Patel, M.M.; Ray, R.M.

1993-01-01

A few metal complexes of α-oximinoacetoacet-o/p-anisidide thiosemicarbazones (OAOATS)/(OAPATS) with Ni(II), Co(II), Zn(II), Mn(II), Hg(II), Cd(II) and UO 2 (II) have been prepared and characterized by elemental analyses, conductivity, differential scanning calorimetry study, thermogravimetric analyses and infrared and electronic spectral measurements in conjunction with magnetic susceptibility measurements at room temperature. They have also been tested for their antimicrobial activities. (author). 24 refs., 2 tabs

Competitive adsorption of copper(II), cadmium(II), lead(II) and zinc(II) onto basic oxygen furnace slag

International Nuclear Information System (INIS)

Xue Yongjie; Hou Haobo; Zhu Shujing

2009-01-01

Polluted and contaminated water can often contain more than one heavy metal species. It is possible that the behavior of a particular metal species in a solution system will be affected by the presence of other metals. In this study, we have investigated the adsorption of Cd(II), Cu(II), Pb(II), and Zn(II) onto basic oxygen furnace slag (BOF slag) in single- and multi-element solution systems as a function of pH and concentration, in a background solution of 0.01 M NaNO 3 . In adsorption edge experiments, the pH was varied from 2.0 to 13.0 with total metal concentration 0.84 mM in the single element system and 0.21 mM each of Cd(II), Cu(II), Pb(II), and Zn(II) in the multi-element system. The value of pH 50 (the pH at which 50% adsorption occurs) was found to follow the sequence Zn > Cu > Pb > Cd in single-element systems, but Pb > Cu > Zn > Cd in the multi-element system. Adsorption isotherms at pH 6.0 in the multi-element systems showed that there is competition among various metals for adsorption sites on BOF slag. The adsorption and potentiometric titrations data for various slag-metal systems were modeled using an extended constant-capacitance surface complexation model that assumed an ion-exchange process below pH 6.5 and the formation of inner-sphere surface complexes at higher pH. Inner-sphere complexation was more dominant for the Cu(II), Pb(II) and Zn(II) systems

Competitive adsorption of copper(II), cadmium(II), lead(II) and zinc(II) onto basic oxygen furnace slag

Energy Technology Data Exchange (ETDEWEB)

Xue Yongjie [School of Resource and Environment Science, Wuhan University, Hubei, Wuhan (China); Wuhan Kaidi Electric Power Environmental Protection Co. Ltd., Hubei, Wuhan (China)], E-mail: xueyj@mail.whut.edu.cn; Hou Haobo; Zhu Shujing [School of Resource and Environment Science, Wuhan University, Hubei, Wuhan (China)

2009-02-15

Polluted and contaminated water can often contain more than one heavy metal species. It is possible that the behavior of a particular metal species in a solution system will be affected by the presence of other metals. In this study, we have investigated the adsorption of Cd(II), Cu(II), Pb(II), and Zn(II) onto basic oxygen furnace slag (BOF slag) in single- and multi-element solution systems as a function of pH and concentration, in a background solution of 0.01 M NaNO{sub 3}. In adsorption edge experiments, the pH was varied from 2.0 to 13.0 with total metal concentration 0.84 mM in the single element system and 0.21 mM each of Cd(II), Cu(II), Pb(II), and Zn(II) in the multi-element system. The value of pH{sub 50} (the pH at which 50% adsorption occurs) was found to follow the sequence Zn > Cu > Pb > Cd in single-element systems, but Pb > Cu > Zn > Cd in the multi-element system. Adsorption isotherms at pH 6.0 in the multi-element systems showed that there is competition among various metals for adsorption sites on BOF slag. The adsorption and potentiometric titrations data for various slag-metal systems were modeled using an extended constant-capacitance surface complexation model that assumed an ion-exchange process below pH 6.5 and the formation of inner-sphere surface complexes at higher pH. Inner-sphere complexation was more dominant for the Cu(II), Pb(II) and Zn(II) systems.

Competitive adsorption of copper(II), cadmium(II), lead(II) and zinc(II) onto basic oxygen furnace slag.

Science.gov (United States)

Xue, Yongjie; Hou, Haobo; Zhu, Shujing

2009-02-15

Polluted and contaminated water can often contain more than one heavy metal species. It is possible that the behavior of a particular metal species in a solution system will be affected by the presence of other metals. In this study, we have investigated the adsorption of Cd(II), Cu(II), Pb(II), and Zn(II) onto basic oxygen furnace slag (BOF slag) in single- and multi-element solution systems as a function of pH and concentration, in a background solution of 0.01M NaNO(3). In adsorption edge experiments, the pH was varied from 2.0 to 13.0 with total metal concentration 0.84mM in the single element system and 0.21mM each of Cd(II), Cu(II), Pb(II), and Zn(II) in the multi-element system. The value of pH(50) (the pH at which 50% adsorption occurs) was found to follow the sequence Zn>Cu>Pb>Cd in single-element systems, but Pb>Cu>Zn>Cd in the multi-element system. Adsorption isotherms at pH 6.0 in the multi-element systems showed that there is competition among various metals for adsorption sites on BOF slag. The adsorption and potentiometric titrations data for various slag-metal systems were modeled using an extended constant-capacitance surface complexation model that assumed an ion-exchange process below pH 6.5 and the formation of inner-sphere surface complexes at higher pH. Inner-sphere complexation was more dominant for the Cu(II), Pb(II) and Zn(II) systems.

Preparation of Schiff s base complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) and their spectroscopic, magnetic, thermal, and antifungal studies

International Nuclear Information System (INIS)

Parekh, H.M.; Patel, M.N.

2006-01-01

The potassium salt of salicylidene-DL-alanine (KHL), bis(benzylidene)ethylenediamine (A 1 ), thiophene-o-carboxaldene-p-toluidine (A 2 ), and its metal complexes of the formula [(M II (L)(A)(H 2 O)] (M=Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II); A = A 1 or A 2 ) are prepared. They are characterized by elemental analysis, magnetic susceptibility measurements, thermogravimetric analysis, and infrared and electronic spectral studies. The electronic spectral and magnetic moment data suggest an octahedral geometry for the complexes. All of these complexes, metal nitrates, fungicides (bavistin and emcarb), and ligands are screened for their antifungal activity against Aspergillus niger, Fusarium oxysporum, and Aspergillus flavus using a plate poison technique. The complexes show higher activity than those of the free ligands, metal nitrate, and the control (DMSO) and moderate activity against bavistin and emcarb [ru

Cu(II) AND Zn(II)

African Journals Online (AJOL)

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SYNTHESIS OF 2,2-DIMETHYL-4-PHENYL-[1,3]-DIOXOLANE USING ZEOLITE. ENCAPSULATED Co(II), Cu(II) AND Zn(II) COMPLEXES. B.P. Nethravathi1, K. Rama Krishna Reddy2 and K.N. Mahendra1*. 1Department of Chemistry, Bangalore University, Bangalore-560001, India. 2Department of Chemistry, Government ...

Spectroscopic and thermal degradation behavior of Mg(II, Ca(II, Ba(II and Sr(II complexes with paracetamol drug

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Moamen S. Refat

2017-05-01

Full Text Available Complexes of Mg(II, Ca(II, Ba(II and Sr(II with paracetamol drug were synthesized and characterized by elemental analysis, conductivity, UV–Vis, IR, and 1H NMR spectroscopy and thermal analysis, as well as screened for antimicrobial activity. The IR spectral data suggested that the ligand behaves as paracetamol behaves as a neutral bidentate ligand coordinated to the metal ions via the lone pair of electrons of nitrogen and carbonyl-O atoms of the amide group. From the microanalytical data, the stoichiometry of the complexes reacts with Mg(II, Ca(II, Ba(II and Sr(II by molar ratios (2:1 (paracetamol:metal ion. The thermal behavior (TG/DTG of the complexes was studied. The ligand and their metal complexes were screened against both of antibacterial and fungicidal activities.

A de novo NADPH generation pathway for improving lysine production of Corynebacterium glutamicum by rational design of the coenzyme specificity of glyceraldehyde 3-phosphate dehydrogenase.

Science.gov (United States)

Bommareddy, Rajesh Reddy; Chen, Zhen; Rappert, Sugima; Zeng, An-Ping

2014-09-01

Engineering the cofactor availability is a common strategy of metabolic engineering to improve the production of many industrially important compounds. In this work, a de novo NADPH generation pathway is proposed by altering the coenzyme specificity of a native NAD-dependent glyceraldehyde 3-phosphate dehydrogenase (GAPDH) to NADP, which consequently has the potential to produce additional NADPH in the glycolytic pathway. Specifically, the coenzyme specificity of GAPDH of Corynebacterium glutamicum is systematically manipulated by rational protein design and the effect of the manipulation for cellular metabolism and lysine production is evaluated. By a combinatorial modification of four key residues within the coenzyme binding sites, different GAPDH mutants with varied coenzyme specificity were constructed. While increasing the catalytic efficiency of GAPDH towards NADP enhanced lysine production in all of the tested mutants, the most significant improvement of lysine production (~60%) was achieved with the mutant showing similar preference towards both NAD and NADP. Metabolic flux analysis with (13)C isotope studies confirmed that there was no significant change of flux towards the pentose phosphate pathway and the increased lysine yield was mainly attributed to the NADPH generated by the mutated GAPDH. The present study highlights the importance of protein engineering as a key strategy in de novo pathway design and overproduction of desired products. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Enhancing poly-γ-glutamic acid production in Bacillus amyloliquefaciens by introducing the glutamate synthesis features from Corynebacterium glutamicum.

Science.gov (United States)

Feng, Jun; Quan, Yufen; Gu, Yanyan; Liu, Fenghong; Huang, Xiaozhong; Shen, Haosheng; Dang, Yulei; Cao, Mingfeng; Gao, Weixia; Lu, Xiaoyun; Wang, Yi; Song, Cunjiang; Wang, Shufang

2017-05-22

Poly-γ-glutamic acid (γ-PGA) is a valuable polymer with glutamate as its sole precursor. Enhancement of the intracellular glutamate synthesis is a very important strategy for the improvement of γ-PGA production, especially for those glutamate-independent γ-PGA producing strains. Corynebacterium glutamicum has long been used for industrial glutamate production and it exhibits some unique features for glutamate synthesis; therefore introduction of these metabolic characters into the γ-PGA producing strain might lead to increased intracellular glutamate availability, and thus ultimate γ-PGA production. In this study, the unique glutamate synthesis features from C. glutamicum was introduced into the glutamate-independent γ-PGA producing Bacillus amyloliquefaciens NK-1 strain. After introducing the energy-saving NADPH-dependent glutamate dehydrogenase (NADPH-GDH) pathway, the NK-1 (pHT315-gdh) strain showed slightly increase (by 9.1%) in γ-PGA production. Moreover, an optimized metabolic toggle switch for controlling the expression of ɑ-oxoglutarate dehydrogenase complex (ODHC) was introduced into the NK-1 strain, because it was previously shown that the ODHC in C. glutamicum was completely inhibited when glutamate was actively produced. The obtained NK-PO1 (pHT01-xylR) strain showed 66.2% higher γ-PGA production than the NK-1 strain. However, the further combination of these two strategies (introducing both NADPH-GDH pathway and the metabolic toggle switch) did not lead to further increase of γ-PGA production but rather the resultant γ-PGA production was even lower than that in the NK-1 strain. We proposed new metabolic engineering strategies to improve the γ-PGA production in B. amyloliquefaciens. The NK-1 (pHT315-gdh) strain with the introduction of NADPH-GDH pathway showed 9.1% improvement in γ-PGA production. The NK-PO1 (pHT01-xylR) strain with the introduction of a metabolic toggle switch for controlling the expression of ODHC showed 66.2% higher �

NCBI nr-aa BLAST: CBRC-CREM-01-1346 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-CREM-01-1346 ref|NP_939160.1| Na(+)/H(+) antiporter homolog [Corynebacterium diphtheria...e NCTC 13129] emb|CAE49312.1| Na(+)/H(+) antiporter homolog [Corynebacterium diphtheriae] NP_939160.1 2e-34 34% ...

Growth-suppressing and algicidal properties of an extract from Arundo donax, an invasive riparian plant, against Prymnesium parvum, an invasive harmful alga

Science.gov (United States)

Patino, Reynaldo; Rashel, Rakib H.; Rubio, Amede; Longing, Scott

2018-01-01

This study examined the ability of acidic and neutral/alkaline fractions of a methanolic extract from giant reed (Arundo donax) and of two of its constituents, gramine and skatole, to inhibit growth of the ichthyotoxic golden alga (Prymnesium parvum) in batch culture. For this study, growth suppression was defined as inhibition of maximum cell density, algicidal activity as early occurrence of negative growth, and algistatic activity as lack of net growth. The acidic fraction did not affect algal growth. The neutral/alkaline fraction showed growth-suppressing and algicidal activities but no signs of algistatic activity – namely, cells in cultures surviving a partial-algicidal exposure concentration (causing transient negative growth) were later able to initiate positive growth but at higher concentrations, algicidal activity was full and irreversible. Gramine suppressed growth more effectively than skatole and at the highest concentration tested, gramine also showed partial-algicidal and algistatic activity. While the partial-algicidal activities of the neutral/alkaline fraction and of gramine were short-lived (≤6 days) and thus may share similar mechanisms, algistatic activity was unique to gramine and persisted for >3 weeks. Given gramine’s reported concentration in the neutral/alkaline fraction, its corresponding level of algicidal activity is much lower than the fraction’s suggesting the latter contains additional potent algicides. Inhibition of maximum cell density by all test compounds was associated with reductions in exponential growth rate, and in the case of the neutral/alkaline fraction and gramine also reductions in early (pre-exponential) growth. These results indicate that giant reed is a potential source of natural products to control golden alga blooms. Giant reed is an invasive species in North America, thus also providing incentive for research into strategies to couple management efforts for both species.

Solar photocatalytic removal of Cu(II), Ni(II), Zn(II) and Pb(II): Speciation modeling of metal-citric acid complexes

International Nuclear Information System (INIS)

Kabra, Kavita; Chaudhary, Rubina; Sawhney, R.L.

2008-01-01

The present study is targeted on solar photocatalytic removal of metal ions from wastewater. Photoreductive deposition and dark adsorption of metal ions Cu(II), Ni(II), Pb(II) and Zn(II), using solar energy irradiated TiO 2 , has been investigated. Citric acid has been used as a hole scavenger. Modeling of metal species has been performed and speciation is used as a tool for discussing the photodeposition trends. Ninety-seven percent reductive deposition was obtained for copper. The deposition values of other metals were significantly low [nickel (36.4%), zinc (22.2%) and lead (41.4%)], indicating that the photocatalytic treatment process, using solar energy, was more suitable for wastewater containing Cu(II) ions. In absence of citric acid, the decreasing order deposition was Cu(II) > Ni(II) > Pb(II) > Zn(II), which proves the theoretical thermodynamic predictions about the metals

Boosting Anaplerotic Reactions by Pyruvate Kinase Gene Deletion and Phosphoenolpyruvate Carboxylase Desensitization for Glutamic Acid and Lysine Production in Corynebacterium glutamicum.

Science.gov (United States)

Yokota, Atsushi; Sawada, Kazunori; Wada, Masaru

In the 1980s, Shiio and coworkers demonstrated using random mutagenesis that the following three phenotypes were effective for boosting lysine production by Corynebacterium glutamicum: (1) low-activity-level citrate synthase (CS L ), (2) phosphoenolpyruvate carboxylase (PEPC) resistant to feedback inhibition by aspartic acid (PEPC R ), and (3) pyruvate kinase (PYK) deficiency. Here, we reevaluated these phenotypes and their interrelationship in lysine production using recombinant DNA techniques.The pyk deletion and PEPC R (D299N in ppc) independently showed marginal effects on lysine production, but both phenotypes synergistically increased lysine yield, demonstrating the importance of PEPC as an anaplerotic enzyme in lysine production. Similar effects were also found for glutamic acid production. CS L (S252C in gltA) further increased lysine yield. Thus, using molecular techniques, the combination of these three phenotypes was reconfirmed to be effective for lysine production. However, a simple CS L mutant showed instabilities in growth and lysine yield.Surprisingly, the pyk deletion was found to increase biomass production in wild-type C. glutamicum ATCC13032 under biotin-sufficient conditions. The mutant showed a 37% increase in growth (based on OD 660 ) compared with the ATCC13032 strain in a complex medium containing 100 g/L glucose. Metabolome analysis revealed the intracellular accumulation of excess precursor metabolites. Thus, their conversion into biomass was considered to relieve the metabolic distortion in the pyk-deleted mutant. Detailed physiological studies of various pyk-deleted mutants also suggested that malate:quinone oxidoreductase (MQO) is important to control both the intracellular oxaloacetic acid (OAA) level and respiration rate. These findings may facilitate the rational use of C. glutamicum in fermentation industries.

Functional architecture and global properties of the Corynebacterium glutamicum regulatory network: Novel insights from a dataset with a high genomic coverage.

Science.gov (United States)

Freyre-González, Julio A; Tauch, Andreas

2017-09-10

Corynebacterium glutamicum is a Gram-positive, anaerobic, rod-shaped soil bacterium able to grow on a diversity of carbon sources like sugars and organic acids. It is a biotechnological relevant organism because of its highly efficient ability to biosynthesize amino acids, such as l-glutamic acid and l-lysine. Here, we reconstructed the most complete C. glutamicum regulatory network to date and comprehensively analyzed its global organizational properties, systems-level features and functional architecture. Our analyses show the tremendous power of Abasy Atlas to study the functional organization of regulatory networks. We created two models of the C. glutamicum regulatory network: all-evidences (containing both weak and strong supported interactions, genomic coverage=73%) and strongly-supported (only accounting for strongly supported evidences, genomic coverage=71%). Using state-of-the-art methodologies, we prove that power-law behaviors truly govern the connectivity and clustering coefficient distributions. We found a non-previously reported circuit motif that we named complex feed-forward motif. We highlighted the importance of feedback loops for the functional architecture, beyond whether they are statistically over-represented or not in the network. We show that the previously reported top-down approach is inadequate to infer the hierarchy governing a regulatory network because feedback bridges different hierarchical layers, and the top-down approach disregards the presence of intermodular genes shaping the integration layer. Our findings all together further support a diamond-shaped, three-layered hierarchy exhibiting some feedback between processing and coordination layers, which is shaped by four classes of systems-level elements: global regulators, locally autonomous modules, basal machinery and intermodular genes. Copyright © 2016 Elsevier B.V. All rights reserved.

Prevalence of Giardia and Cryptosporidium in beef cows in southern Ontario and in beef calves in southern British Columbia.

Science.gov (United States)

McAllister, Tim A; Olson, Merle E; Fletch, Andy; Wetzstein, Merv; Entz, Toby

2005-01-01

In 1998 and 1999, fecal samples were collected from 669 beef cows on 39 farms located within 10 counties of Ontario. Overall prevalences of Giardia, Cryptosporidium muris, and Cryptosporidium parvum in cows were 8.7%, 10.6%, and 18.4%, respectively. Of the 39 farms sampled, Giardia was detected on 64%, Cr. muris on 72%, and Cr. parvum on 90%. Cryptosporidium parvum was detected in 28% of the cows in 1998 and in 5.2% in 1999. Differences between the 2 y were attributed to sampling during calving in 1998 and during gestation in 1999. In 1998, Giardia, Cr. muris, and Cr. parvum were detected in herds provided with municipal water. In 1998, 193 calves were sampled from 10 farms, representing 4 watersheds, in British Columbia. Thirty-six percent of the calves exhibited signs of diarrhea. Overall prevalences of Giardia and Cryptosporidium spp. in calves were 36% and 13%, respectively. There was evidence that calves with Giardia were more likely to develop scours. Restricting cattle from surface water during periods of high shedding may reduce watershed contamination.

Single-dose Intramuscular-injection Toxicology Test of Water-soluble Carthami-flos and Cervi cornu parvum Pharmacopuncture in a Rat Model

Directory of Open Access Journals (Sweden)

Sunju Park

2015-09-01

Full Text Available Objectives: The aim of the study is to investigate both the single-dose intramuscular injection toxicity and the approximate lethal dose of water-soluble Carthami-flos and Cervi cornu parvum pharmacopuncture (WCFC in male and female Sprague-Dawley (SD rats. Methods: The study was conducted at Biotoxtech Co. according to the Good Laboratory Practice (GLP regulation and the toxicity test guidelines of the Ministry of Food and Drug Safety (MFDS after approval of the Institutional Animal Care and Use Committee. Dosages for the control, high dose, middle dose and low dose groups were 0.5 mL/animal of saline and 0.5, 0.25 and 0.125 mL/animal of WCFC, respectively. WCFC was injected into the muscle of the left femoral region by using a disposable syringe (1 mL, 26 gauge. The general symptoms and mortality were observed 30 minutes, 1, 2, 4, and 6 hours after the first injection and then daily for 14 days after the injection. The body weights of the SD rats were measured on the day of the injection (before injection and on the third, seventh, and fourteenth days after the injection. Serum biochemical and hematologic tests, necropsy examinations, and histopathologic examinations at the injection site were performed after the observation period. Results: No deaths, abnormal clinical symptoms, or significant weight changes were observed in either male or female SD rats in the control or the test (0.125, 0.25, and 0.5 mL/animal groups during the observation period. No significant differences in hematology and serum biochemistry and no macroscopic abnormalities at necropsy were found. No abnormal reactions at injection sites were noted on the topical tolerance tests. Conclusion: The results of this single-dose toxicity study show that WCFC is safe, its lethal doses in male and female SD rats being estimated to be higher than 0.5 mL/animal.

Cd(II), Cu(II)

African Journals Online (AJOL)

user

Depending on the way goethite was pretreated with oxalic acid, affinity for Cd(II) varied ...... Effects and mechanisms of oxalate on Cd(II) adsorption on goethite at different ... precipitation, surfactant mediation, hydrothermal and micro-emulsion.

Corynebacterium glutamicum MTCC 2745 immobilized on granular activated carbon/MnFe2O4 composite: A novel biosorbent for removal of As(III) and As(V) ions.

Science.gov (United States)

Podder, M S; Majumder, C B

2016-11-05

The optimization of biosorption/bioaccumulation process of both As(III) and As(V) has been investigated by using the biosorbent; biofilm of Corynebacterium glutamicum MTCC 2745 supported on granular activated carbon/MnFe2O4 composite (MGAC). The presence of functional groups on the cell wall surface of the biomass that may interact with the metal ions was proved by FT-IR. To determine the most appropriate correlation for the equilibrium curves employing the procedure of the non-linear regression for curve fitting analysis, isotherm studies were performed for As(III) and As(V) using 30 isotherm models. The pattern of biosorption/bioaccumulation fitted well with Vieth-Sladek isotherm model for As(III) and Brouers-Sotolongo and Fritz-Schlunder-V isotherm models for As(V). The maximum biosorption/bioaccumulation capacity estimated using Langmuir model were 2584.668mg/g for As(III) and 2651.675mg/g for As(V) at 30°C temperature and 220min contact time. The results showed that As(III) and As(V) removal was strongly pH-dependent with an optimum pH value of 7.0. D-R isotherm studies specified that ion exchange might play a prominent role. Copyright © 2016 Elsevier B.V. All rights reserved.

NCBI nr-aa BLAST: CBRC-AGAM-01-0038 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-AGAM-01-0038 ref|NP_938793.1| Putative cytochrome C biogenesis protein [Corynebacterium diphtheria...e NCTC 13129] emb|CAE48916.1| Putative cytochrome C biogenesis protein [Corynebacterium diphtheriae] NP_938793.1 1.6 24% ...

Sequestration of Cu(II), Ni(II), and Co(II) by ethyleneimine immobilized on silica

International Nuclear Information System (INIS)

Arakaki, Luiza N.H.; Alves, Ana Paula M.; Silva Filho, Edson C. da; Fonseca, Maria G.; Oliveira, Severino F.; Espinola, Jose Geraldo P.; Airoldi, Claudio

2007-01-01

Thermodynamic data on interaction of Cu(II), Ni(II), and Co(II) with silica modified with ethyleneimine are obtained by calorimetric titration. The amount of ethyleneimine anchored on silica surface was estimated to be 0.70 mmol g -1 . The enthalpies of binding Ni(II), Cu(II) and Co(II), are -3.59 ± 0.001, -4.88 ± 0.001, and -7.75 ± 0.003 kJ mol -1 , respectively

NCBI nr-aa BLAST: CBRC-PTRO-20-0007 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-PTRO-20-0007 ref|NP_938605.1| immunity-specific protein Beta241 [Corynebacterium diphtheria...e NCTC 13129] emb|CAE48718.1| immunity-specific protein Beta241 [Corynebacterium diphtheriae] NP_938605.1 1e-04 24% ...

Solid-phase extraction of Mn(II), Co(II), Ni(II), Cu(II), Cd(II) and Pb(II) ions from environmental samples by flame atomic absorption spectrometry (FAAS)

Energy Technology Data Exchange (ETDEWEB)

Duran, Celal [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Gundogdu, Ali [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Bulut, Volkan Numan [Department of Chemistry, Giresun Faculty of Art and Science, Karadeniz Technical University, 28049 Giresun (Turkey); Soylak, Mustafa [Department of Chemistry, Faculty of Art and Science, Erciyes University, 38039 Kayseri (Turkey)]. E-mail: soylak@erciyes.edu.tr; Elci, Latif [Department of Chemistry, Faculty of Art and Science, Pamukkale University, 20020 Denizli (Turkey); Sentuerk, Hasan Basri [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey); Tuefekci, Mehmet [Department of Chemistry, Faculty of Art and Science, Karadeniz Technical University, 61080 Trabzon (Turkey)

2007-07-19

A new method using a column packed with Amberlite XAD-2010 resin as a solid-phase extractant has been developed for the multi-element preconcentration of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), and Pb(II) ions based on their complex formation with the sodium diethyldithiocarbamate (Na-DDTC) prior to flame atomic absorption spectrometric (FAAS) determinations. Metal complexes sorbed on the resin were eluted by 1 mol L{sup -1} HNO{sub 3} in acetone. Effects of the analytical conditions over the preconcentration yields of the metal ions, such as pH, quantity of Na-DDTC, eluent type, sample volume and flow rate, foreign ions etc. have been investigated. The limits of detection (LOD) of the analytes were found in the range 0.08-0.26 {mu}g L{sup -1}. The method was validated by analyzing three certified reference materials. The method has been applied for the determination of trace elements in some environmental samples.