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determinants of the human infant intestinal microbiota after the introduction of first complementary foods in infant samples from five european centres.although it is well established that early infant feeding has a major influence on the establishment of the gut microbiota, very little is understood about how the introduction of first solid food influences the colonization process. this study aimed to determine the impact of weaning on the faecal microbiota composition of infants from five european countries (sweden, scotland, germany, italy and spain) which have different lifestyle characteristics and infant feeding practices. faecal samples ...201121330436
[evaluation of two techniques for detecting clostridium perfringens enterotoxin in faecal samples]. 201121333401
management of gas gangrene in wenchuan earthquake victims.gas gangrene is an emergency condition, which usually develops after injuries or surgery. this study was designed to investigate clinical characteristics, appropriate therapy, and effective control of nosocomial cross-infection of gas gangrene in wenchuan earthquake victims. data on diagnosis, treatment, and prevention of confirmed, suspected, or highly suspected gas gangrene were collected. sixty-seven (2.41%) cases of suspected gas gangrene were found, in which 32 cases were highly suspected o ...201121336729
a novel screening system for claudin binder using baculoviral display.recent progress in cell biology has provided new insight into the claudin (cl) family of integral membrane proteins, which contains more than 20 members, as a target for pharmaceutical therapy. few ligands for cl have been identified because it is difficult to prepare cl in an intact form. in the present study, we developed a method to screen for cl binders by using the budded baculovirus (bv) display system. cl4-displaying bv interacted with a cl4 binder, the c-terminal fragment of clostridium ...201121339813
assessment of clostridium perfringens spore response to high hydrostatic pressure and heat with nisin.the elimination of spores from low-acid foods presents food-processing and food-safety challenges to high-pressure processing (hpp) developers as bacterial spores are extremely resistant to pressure. therefore, the effects of pressure (400-800 mpa), temperature (35-95 °c), and nisin (0-496 iu/ml) on the inactivation of clostridium perfringens as 64701 spores at various pressure-holding times (7.5-17.5 min) were explored. a second-order polynomal equation for hpp- and nisin-induced inactivation o ...201121340537
identification and cloning of two immunogenic clostridium perfringens proteins, elongation factor tu (ef-tu) and pyruvate:ferredoxin oxidoreductase (pfo) of c. perfringens.clostridium-related poultry diseases such as necrotic enteritis (ne) and gangrenous dermatitis (gd) cause substantial economic losses on a global scale. two antigenic clostridium perfringens proteins, elongation factor tu (ef-tu) and pyruvate:ferredoxin oxidoreductase (pfo), were identified by reaction with immune sera from commercial meat-type chickens with clinical outbreak of clostridium infections. in addition to the genes encoding ef-tu and pfo, c. perfringens alpha-toxin and necrotic enter ...201121345474
hot water surface pasteurisation of lamb carcasses: microbial effects and cost-benefit considerations.although hot water pasteurisation of carcasses is accepted as a general intervention in usa, this is not the case in europe. the aims of this study were (i) to evaluate the microbiological effects of hot water pasteurisation of lamb carcasses, both after slaughtering and dressing and following subsequent chilling and storage; (ii) to discuss hot water pasteurisation from a public health and cost-benefit perspective; (iii) to discuss the benefits of hot water pasteurisation compared with use of s ...201121356564
comparative analysis of fecal microbiota and intestinal microbial metabolic activity in captive polar bears.the composition of the intestinal microbiota depends on gut physiology and diet. ursidae possess a simple gastrointestinal system composed of a stomach, small intestine, and indistinct hindgut. this study determined the composition and stability of fecal microbiota of 3 captive polar bears by group-specific quantitative pcr and pcr-dgge (denaturing gradient gel electrophoresis) using the 16s rrna gene as target. intestinal metabolic activity was determined by analysis of short-chain fatty acids ...201121358758
survival and growth of clostridium perfringens in commercial no-nitrate-or-nitrite-added (natural and organic) frankfurters, hams, and bacon.the popularity of "preservative-free" foods among consumers has stimulated rapid growth of processed meats manufactured without sodium nitrite. the objective of this study was to quantify the potential for clostridium perfringens growth in commercially available processed meats manufactured without the direct addition of nitrite or nitrate. commercial brands of naturally cured, no-nitrate-or-nitrite-added frankfurters (10 samples), hams (7 samples), and bacon (9 samples) were obtained from retai ...201121375877
use of natural ingredients to control growth of clostridium perfringens in naturally cured frankfurters and hams.a major concern for processed meats marketed as natural/organic is that they do not contain nitrite in concentrations known to be most effective for inhibiting foodborne pathogens. supplemental treatments to increase the level and consistency of antimicrobial protection in these products may be important to provide consumers with the degree of safety that they have come to expect from conventionally cured meats. therefore, the objective of this study was to identify and test ingredients that mig ...201121375878
diversity of expressed vlha adhesin sequences and intermediate hemagglutination phenotypes in mycoplasma synoviae.a reservoir of pseudogene alleles encoding the primary adhesin vlha occurs in the avian pathogen mycoplasma synoviae. recombination between this reservoir and its single expression site was predicted to result in lineages of m. synoviae that each express a different vlha allele as a consequence of host immune responses to those antigens. such interstrain diversity at the vlha expression site, including major differences in the predicted secondary structures of their expressed adhesins, was confi ...201121378196
alternative cooling procedures for large, intact meat products to achieve stabilization microbiological performance standards.achieving the u. s. department of agriculture, food safety and inspection service (usda-fsis) stabilization microbiological performance standards for cooling procedures proves to be challenging for processors of large, whole-muscle meat products. this study was conducted to determine if slower cooling times than those provided by usda-fsis guidance will comply with the performance standard for clostridium perfringens. large (9 to 12 kg) cured bone-in hams (n = 110) and large (8 to 13 kg) uncured ...201121219768
fecal pollution in coastal marine sediments from a semi-enclosed deep embayment subjected to anthropogenic activities: an issue to be considered in environmental quality management frameworks development.sewage discharge is a major source of pollution in marine environments. urban wastewaters can directly enter marine environments carrying pathogen organisms, organic loads, and nutrients. because marine sediments can act as the ultimate fate of a wide range of pollutants, environmental quality assessment in this compartment can help to identify pollution problems in coastal areas. in the present study, characterization of surficial marine sediments allowed assessment of fecal pollution in a semi ...201121225312
enterococcus faecalis virulence regulator fsra binding to target promoters.the fsrabdc signal transduction system is a major virulence regulator in enterococcus faecalis. the fsrc sensor histidine kinase, upon activation by the gelatinase biosynthesis-activating pheromone (gbap) peptide encoded by the fsrbd genes, phosphorylates the fsra response regulator required for the transcription of the fsrbdc and the gele-spre genes from the fsrb promoter and the gele promoter, respectively. fsra belongs to the lyttr family of proteins, which includes other virulence regulators ...201121257771
effect of lactobacillus plantarum lp-onlly on gut flora and colitis in interleukin-10 knockout mice.probiotics are used in the therapy of inflammatory bowel disease. this study aimed to determine the effects of probiotic lactobacillus plantarum lp-onlly (lp) on gut flora and colitis in interleukin-10 knockout (il-10(-/-) ) mice, a model of spontaneous colitis.201121261733
in vitro measurement of the impact of human milk oligosaccharides on the faecal microbiota of weaned formula-fed infants compared to a mixture of prebiotic fructooligosaccharides and galactooligosaccharides.to investigate the impact of human milk oligosaccharides (hmos) from a single donor (so), hmos from multiple donors (po), a fructooligosaccharides and galactooligosaccharides mixture (fg) on the composition of a batch culture inoculated with faecal microbiota from formula-fed infants.201121214609
postoperative complications in a lamb after major surgery.intoduction: anaesthesia in lambs undergoing experimental surgery may develop problems associated with age-related immune incompetency: a postoperative complication in a 3 week old scottish blackface lamb after spinal surgery is presented. case history and management: both lamb and ewe were in good condition. the ewe was vaccinated against clostridium perfringens and clostridium tetani 5 weeks pre-partum. there were no apparent problems with the lamb's intake of colostrum. pre-anaesthetic medica ...201121214711
germination response of spores of the pathogenic bacterium clostridium perfringens and clostridium difficile to cultured human epithelial cells.spores of pathogenic clostridium perfringens and clostridium difficile must germinate in the food vehicle and/or host's intestinal tract to cause disease. in this work, we examined the germination response of spores of c. perfringens and c. difficile upon incubation with cultured human epithelial cell lines (caco-2, hela and ht-29). c. perfringens spores of various sources were able to germinate to different extents; while spores of a non-food-borne isolate germinated very well, spores of food-b ...201121315167
the virs/virr two-component system regulates the anaerobic cytotoxicity, intestinal pathogenicity, and enterotoxemic lethality of clostridium perfringens type c isolate cn3685.clostridium perfringens vegetative cells cause both histotoxic infections (e.g., gas gangrene) and diseases originating in the intestines (e.g., hemorrhagic necrotizing enteritis or lethal enterotoxemia). despite their medical and veterinary importance, the molecular pathogenicity of c. perfringens vegetative cells causing diseases of intestinal origin remains poorly understood. however, c. perfringens beta toxin (cpb) was recently shown to be important when vegetative cells of c. perfringens ty ...201121264065
multilocus sequence typing subtypes of poultry clostridium perfringens isolates demonstrate disease niche partitioning.clostridium perfringens is a ubiquitous and versatile pathogenic bacterium and is implicated in the etiology of the poultry diseases necrotic enteritis (ne) and poultry gangrene (pg). in this study, multilocus sequence typing was used to investigate genotypic relationships among 139 c. perfringens isolates from 74 flocks. these isolates had multiple disease, host, and environmental origins. the results indicated a polymorphic yet highly clonal population, with 79.6% of all isolates partitioning ...201121270221
analysis of bacterial communities of traditional fermented west african cereal foods using culture independent methods.in this study, the microbial composition of kunu-zaki and ogi, two popular foods in nigeria produced after natural, uncontrolled fermentation of cereals, was assessed by culture-independent molecular profiling methods. in particular, pcr-denaturing gradient gel electrophoresis and construction of 16s rrna gene clone libraries revealed the presence of diverse bacterial communities. dna sequencing of the highly variable v3 region of the 16s rrna genes obtained from pcr-dgge fingerprints identified ...201121272950
intestinal microbiota was assessed in cirrhotic patients with hepatitis b virus infection. intestinal microbiota of hbv cirrhotic patients.to unravel the profile of intestinal microecological parameters in chinese patients with asymptomatic carriage of hepatitis b virus (hbv), chronic hepatitis b, decompensated hbv cirrhosis, and health controls and to establish their correlation with liver disease progression, we performed quantitative pcr and immunological techniques to investigate fecal parameters, including population of fecal predominant bacteria and the abundance of some virulence genes derived from escherichia coli, bacteroi ...201121286703
expression and purification of functional clostridium perfringens alpha and epsilon toxins in escherichia coli.the alpha and epsilon toxins are 2 of the 4 major lethal toxins of the pathogen clostridium perfringens. in this study, the expression of the epsilon toxin (etx) gene of c. perfringens was optimized by replacing rare codons with high-frequency codons, and the optimized gene was synthesized using overlapping pcr. then, the etx gene or the alpha-toxin gene (cpa) was individually inserted into the ptig-trx expression vector with a hexahistidine tag and a thioredoxin (trx) to facilitate their purifi ...201121300155
cost-effective screening of pooled faecal specimens from patients with nosocomial diarrhoea for clostridium perfringens enterotoxin.clostridium perfringens is a significant cause of nosocomial aad. the prevalence of c. perfringens enterotoxin (cpe)-positive stool specimens in hospitalised patients is very low in the indian setting making the diagnostics very expensive. therefore, a cost-effective diagnostic approach to screen faecal specimens for cpe was devised.201121304197
[A non-invasive drug delivery system using claudin binder].The intercellular spaces between adjacent epithelial cells are sealed by tight junctions (TJs). Modulation of TJ-seal is a potent strategy for drug absorption. Claudin is a key structural and functional component of TJ-seal. Claudin comprises a tetra-transmembrane protein family consisting of more than 20 members, whose expression profiles and barrier-function differ among tissues. For instance, claudin-1 plays roles in the epidermal and mucosal barriers, and claudin-4 regulates the mucosal barr ...201122041696
complex transcriptional regulation of citrate metabolism in clostridium perfringens.a gram-positive, spore-forming bacterium, clostridium perfringens, possesses genes for citrate metabolism, which might play an important role in the utilization of citrate as a sole carbon source. in this study, we identified a chromosomal citcdefx-mae-cits operon in c. perfringens strain 13, which is transcribed on three mrnas of different sizes. expression of the cit operon was significantly induced when 5 mm extracellular citrate was added to the growth medium. most interestingly, three regul ...201121945821
Successful treatment of necrotizing fasciitis in an upper extremity caused by Clostridium perfringens after bone marrow transplantation.We report a 47-year-old man with acute leukemia who survived a severe case of necrotizing fasciitis caused by Clostridium perfringens involving his right upper extremity. On day 5 after stem cell transplantation, progressive local tissue necrosis led to septicemia and disseminated intravascular coagulation. Early diagnosis and prompt initiation of appropriate therapy, including surgical debridement and broad-spectrum antibiotics, were crucial. A recombinant thrombomodulin might have not only res ...201121963743
potentially pathogenic bacteria and antimicrobial resistance in bioaerosols from cage-housed and floor-housed poultry operations.background: antibiotics are used in animal confinement buildings, such as cage-housed (ch) and floor-housed (fh) poultry operations, to lower the likeliness of disease transmission. in fh facilities, antibiotics may also be used at sub-therapeutic levels for growth promotion. low levels of antibiotic create a selective pressure toward antimicrobial resistance (amr) in chicken fecal bacteria. objective: the objective of this study was to compare bacteria and amr genes in bioaerosols from ch and ...201122156572
identification, isolation and characterization of a novel azoreductase from clostridium perfringens.azo dyes are used widely in the textile, pharmaceutical, cosmetic and food industries as colorants and are often sources of environmental pollution. there are many microorganisms that are able to reduce azo dyes by use of an azoreductase enzyme. it is through the reduction of the azo bonds of the dyes that carcinogenic metabolites are produced thereby a concern for human health. the field of research on azoreductases is growing, but there is very little information available on azoreductases fro ...201122182443
Clostridium perfringens iota-toxin b induces rapid cell necrosis.Clostridium perfringens iota-toxin is a binary toxin composed of an enzyme component (Ia) and a binding component (Ib). Each component alone lacks toxic activity, but together they produce cytotoxic effects. We examined the cytotoxicity of iota-toxin Ib in eight cell lines. A431 and A549 cells were susceptible to Ib, but MDCK, Vero, CHO, Caco-2, HT-29, and DLD-1 cells were not. Ib bound and formed oligomers in the membranes of A431 and MDCK cells. However, Ib entered MDCK cells but not A431 cell ...201121911469
development and validation of stable reference materials for food microbiology using bacillus cereus and clostridium perfringens spores.to develop a new type of microbiological reference materials (rms), displaying long-term stability at room temperature. the purpose was to produce and validate two batches of rms for the enumeration of bacillus cereus and clostridium perfringens.201121435123
review of enteric outbreaks in prisons: effective infection control interventions.to identify documented outbreaks, worldwide, of enteric illness in correctional facilities over the last 10 years to understand the epidemiology of the outbreaks and explicitly identify effective infection control measures.201121440921
[emphysematous cholecystitis due to clostridium perfringens]. 201121427832
antimicrobial susceptibility of clostridium perfringens isolates of bovine, chicken, porcine, and turkey origin from ontario.antimicrobial susceptibilities and toxin types were determined for 275 clostridium perfringens isolates collected in ontario in the spring of 2005. minimal inhibitory concentrations (mics) of c. perfringens isolates for 12 antimicrobials used in therapy, prophylaxis, and/or growth promotion of cattle (n = 40), swine (n = 75), turkeys (n = 50), and chickens (n = 100) were determined using the microbroth dilution method. statistical analyses and mic distributions showed reduced susceptibility to b ...201121731178
chapter 2-12-6. anaerobic infections (individual fields): food poisoning due to clostridium perfringens. 201121728112
the cysteine protease +¦-clostripain is not essential for the pathogenesis of clostridium perfringens-mediated myonecrosis.clostridium perfringens is the causative agent of clostridial myonecrosis or gas gangrene and produces many different extracellular toxins and enzymes, including the cysteine protease +¦-clostripain. mutation of the +¦-clostripain structural gene, ccp, alters the turnover of secreted extracellular proteins in c. perfringens, but the role of +¦-clostripain in disease pathogenesis is not known. we insertionally inactivated the ccp gene c. perfringens strain 13 using targetron technology, construct ...201121829506
effect of trypsin inhibitor activity in soya bean on growth performance, protein digestibility and incidence of sub-clinical necrotic enteritis in broiler chicken flocks.1. the effect of three different levels of dietary trypsin inhibitor activity (achieved by varying the amount of non-toasted full fat soya bean in replacement for toasted full fat soya bean) on the incidence of spontaneously-occurring sub-clinical necrotic enteritis (ne) in broiler chickens was compared. a fourth dietary treatment compared the effect of a diet that used potato protein concentrate as the major protein source. the determined trypsin inhibitor activity increased with the increasing ...201121732882
a novel toxin regulator, the cpe1446-cpe1447 protein heteromeric complex, controls toxin genes in clostridium perfringens.clostridium perfringensis a gram-positive anaerobic spore-forming bacterium that is widespread in environmental soil and sewage, as well as in animal intestines. it is also a causative agent of diseases in humans and other animals, and it produces numerous extracellular enzymes and toxins. although these toxins have been characterized in detail, regulators of toxin genes are less well understood. the present study identified cpe1447 and cpe1446 as novel regulators of toxin gene expression. cpe14 ...201121725013
hygienic quality and antibiotic resistance profile of sliced butchery.in order to investigate the microbiological quality of different meat products on the greek market, 200 samples were collected from the following preparations: boiled turkey (n=50), boiled pork ham (n=50), smoked turkey (n=50) and smoked pork ham (n=50). in all cold meat preparations clostridium perfringens vegetative and spore forms, staphylococcus aureus, escherichia coli and other clostridium sp lec(-), as well as lactobacillus, bacillus sp. and salmonella sp. were recovered. for instance bac ...201121722746
claudin-4: functional studies beyond the tight junction.claudin-4 is an unusual member of the claudin family; in addition to its role in epithelial tight junction barrier function, it is a receptor for the clostridium perfringens enterotoxin. we have also found that claudin-4 is regulated in mucosal epithelium m cells, both in increased expression of the protein and in redistribution into endocytosis vesicles. our ongoing studies are studying the potential for developing ligands specific to claudin-4 for targeted delivery of cargo such as proteins an ...201121717353
evolution of clostridia and streptomycetes in full-scale composting facilities and pilot drums equipped with on-line temperature monitoring and aeration.the evolution of sporulating bacteria in full-scale composting facilities with online temperature monitoring has been poorly studied, although organic matter recycling increases. we analysed clostridium perfringens and sulphite-reducing clostridia (src) by cultivation, and streptomycetes by real-time pcr in five full-scale, temperature-monitored and aerated composting processes, and two pilot-scale drum composters. facilities composted woodchips, sawdust, peat, or bark amended sludge or source-s ...201121719280
structure of the food-poisoning clostridium perfringens enterotoxin reveals similarity to the aerolysin-like pore-forming toxins.clostridium perfringens enterotoxin (cpe) is a major cause of food poisoning and antibiotic-associated diarrhea. upon its release from c. perfringens spores, cpe binds to its receptor, claudin, at the tight junctions between the epithelial cells of the gut wall and subsequently forms pores in the cell membranes. a number of different complexes between cpe and claudin have been observed, and the process of pore formation has not been fully elucidated. we have determined the three-dimensional stru ...201121839091
eradication of chemotherapy-resistant cd44+ human ovarian cancer stem cells in mice by intraperitoneal administration of clostridium perfringens enterotoxin.background: emerging evidence has suggested that the capability to sustain tumor formation, growth, and chemotherapy resistance in ovarian as well as other human malignancies exclusively resides in a small proportion of tumor cells termed cancer stem cells. during the characterization of cd44(+) ovarian cancer stem cells, we found a high expression of the genes encoding for claudin-4. because this tight junction protein is the natural high-affinity receptor for clostridium perfringens enterotoxi ...201121692061
factors associated with the quality of well water and the prevalence of waterborne diseases in the municipality of abomey-calavi in benin.the objective of this work is to assess the factors associated with the water quality of household wells, suggest solutions to improve it, and study the prevalence of water-borne diseases in this community. the quality of well water and the prevalence of waterborne diseases in the municipality were studied by analysis of the microbiological indicators currently used to assess drinking-water quality and the retrospective study of waterborne diseases treated in the local health centres. the wells ...201121700557
effects of necrotic enteritis challenge on intestinal micro-architecture and mucin profile.1. this study investigated the effect of eimeria spp./clostridium perfringens induced necrotic enteritis and traditional antibiotic preventatives on intestinal micro-architecture and mucin profile. 2. a total of 600 cobb 500 broiler chickens were randomly assigned to the following three groups: (i) unchallenged, (ii) challenged, and (iii) zinc bacitracin/monensin (znb/monensin) (n = 25 chickens/pen, 8 pens/group). the challenged and znb/monensin chickens were individually inoculated with eimeria ...201121919578
microbial safety of air-dried and rewetted biosolids.to assess microbial safety of treated sewage sludge (biosolids), we examined the inactivation of microbial indicators for potential bacterial, viral and protozoan pathogens. the levels of indicators were determined throughout the air-drying and storage phases of anaerobically digested sewage sludge. samples were collected from two wastewater treatment plants (wwtps) in victoria, australia. established methods were applied for analysis of bacteria and coliphages, based on membrane filtration and ...201121942204
effect of direct-fed microbials on performance and clostridium perfringens colonization of turkey poults.clostridium perfringens is recognized as an enteric pathogen in humans, domestic animals, and livestock. this organism is associated with necrotic enteritis, gangrenous dermatitis, clostridial dermatitis (turkeys), and gizzard erosions in poultry. this study was conducted to evaluate the effectiveness of a direct-fed microbial (dfm), primalac (star labs, clarksdale, mo), in preventing intestinal colonization of turkey poults with c. perfringens. one-day-old turkey poults (n = 128) were randomly ...201122010255
the effect of probiotics on faecal microbiota and genotoxic activity of faecal water in patients with atopic dermatitis: a randomized, placebo-controlled study.background: colonic microbiota is involved in the etiology of colon cancer according to several reports. studies also indicate that the microbiota differs between atopic patients and healthy subjects. objective: to evaluate whether a probiotic mix containing lactobacillus paracasei lpc-37, lactobacillus acidophilus 74-2, and bifidobacterium animalis subsp. lactis dgcc 420 can affect the microbiota and its genotoxic activity in healthy subjects and patients with atopic dermatitis (ad). methods: a ...201121963389
acid phosphatase test proves superior to standard phenotypic identification procedure for clostridium perfringens strains isolated from water.clostridium perfringens is used as an indicator for persistent faecal pollution as well as to monitor the efficacy of water treatment processes. for these purposes, differentiation between c. perfringens and other clostridia is essential and is routinely carried out by phenotypic standard tests as proposed in the iso/cd 6461-2:2002 (iso_lgmn: lactose fermentation, gelatine liquidation, motility and nitrate reduction). because the iso_lgmn procedure is time consuming and labour intensive, the aci ...201121872622
[Molecular characterization and antimicrobial resistance of Clostridium perfringens isolates of different origins from Costa Rica].Clostridium perfringens, a Gram positive, spore-forming anaerobe, is widely distributed in nature. Based upon their production of four major toxins alpha, beta, epsilon and iota, C. perfringens is classified into five toxinotypes (A-E). Some strains produce an enterotoxin (CPE), encoded by the cpe gene, which causes diarrhea in humans and some animals. C. perfringens strains that had been previously isolated and been kept at -80 degrees C were analyzed for the presence of toxin genes and for ant ...201122208067
Structural analysis of CPF_2247, a novel a-amylase from Clostridium perfringens.CPF_2247 from Clostridium perfringens ATCC 13124 was identified as a putative carbohydrate-active enzyme by its low sequence identity to endo-ß-1,4-glucanases belonging to family 8 of the glycoside hydrolase classification. The X-ray crystal structure of CPF_2247 determined to 2.0 Å resolution by single-wavelength anomalous dispersion using seleno-methionine-substituted protein revealed an (a/a)(6) barrel fold. A large cleft on the surface of the protein contains residues that are structurally c ...201121905105
characterization and distribution of the gene cluster encoding rumc, an anti-clostridium perfringens bacteriocin produced in the gut.ruminococcin c (rumc) is a trypsin-dependent bacteriocin produced by ruminococcus gnavus e1, a gram-positive strict anaerobic strain isolated from human feces. it consists of at least three similar peptides active against clostridium perfringens. in this article, a 15-kb region from r. gnavus e1 chromosome, containing the biosynthetic gene cluster of rumc was characterized. it harbored 17 open reading frames (called rum(c) genes) with predicted functions in bacteriocin biosynthesis and post-tran ...201122092178
mechanism of clostridium perfringens enterotoxin interaction with claudin-3/-4 protein suggests structural modifications of the toxin to target specific claudins.claudins (cld) are essential constituents of tight junctions. domain i of clostridium perfringens enterotoxin (ccpe) binds to the second extracellular loop (ecl2) of a subset of claudins, e.g. cld3/4 and influences tight junction formation. we aimed to identify interacting interfaces and to alter claudin specificity of ccpe. mutagenesis, binding assays, and molecular modeling were performed. mutation-guided ecl2 docking of cld3/4 onto the crystal structure of ccpe revealed a common orientation o ...201122128179
Selection of herbal therapeutics against deltatoxin mediated Clostridial infections.Clostridium perfringens (a versatile pathogenic bacterium) secretes enterotoxins (the deltatoxin, virulent factor) and causes food borne gastroenteritis and gasgangrene. The organism was isolated and characterized from improperly cooked meat and poultry samples. The isolated organism showed multiple drug resistance indicating that the treatment is challenging. Hence, there is need for improved therapeutic agents. The rational design of improved therapeutics requires the crystal structure for the ...201121904424
Functional insight into the C-terminal extension of halolysin SptA from haloarchaeon Natrinema sp. J7.Halolysin SptA from haloarchaeon Natrinema sp. J7 consists of a subtilisin-like catalytic domain and a C-terminal extension (CTE) containing two cysteine residues. In this report, we have investigated the function of the CTE using recombinant enzymes expressed in Haloferax volcanii WFD11. Deletion of the CTE greatly reduced but did not abolish protease activity, which suggests that the CTE is not essential for enzyme folding. Mutational analysis suggests that residues Cys303 and Cys338 within th ...201121886797
effects of non-fermented and fermented soybean milk intake on faecal microbiota and faecal metabolites in humans.the effects of non-fermented soybean milk (nfsm) and fermented soybean milk (fsm) intake on the faecal microbiota and metabolic activities in 10 healthy volunteers were investigated. soybean oligosaccharides, raffinose and stachyose were utilized by bifidobacteria except for bifidobacterium bifidum, but most strains of escherichia coli and clostridium perfringens could not use them. during the dietary administration of fsm, the number of bifidobacteria and lactobacilli in the faeces increased (p ...201122040525
aberrant structures of fecal bacterial community in allergic infants profiled by 16s rrna gene pyrosequencing.we investigated the correlation between fecal bacteria composition in early infancy and the prevalence of allergic diseases in late infancy. the fecal microbiota in the first 2 months was profiled using the 16s rrna v6 short-tag sequences in the community and statistically compared between two groups of subjects who did and did not show allergic symptoms in the first 2 years (n = 11 vs. 11). in the allergic group, genus bacteroides at 1 month and genera propionibacterium and klebsiella at 2 mont ...201122029688
fatal gas gangrene related to self-injection treatment of anaphylaxis. 201121624755
development and application of a mouse intestinal loop model to study the in vivo action of clostridium perfringens enterotoxin.clostridium perfringens enterotoxin (cpe) is responsible for causing the gastrointestinal symptoms of c. perfringens type a food poisoning, the 2(nd) most commonly-identified bacterial foodborne illness in the usa. cpe is produced by sporulating c. perfringens cells in the small intestinal lumen, where it then causes epithelial damage and villous blunting that leads to diarrhea and cramping. those effects are typically self-limiting; however, severe outbreaks of this food poisoning, particularly ...201121628512
fatal case of clostridium perfringens enteritis and bacteraemia in south africa.clostridium perfringens is an important anaerobic pathogen causing foodborne and non-foodborne gastrointestinal diseases in humans and animals. this pathogen is also the more common clostridium species associated with bacteraemia. we report on a fatal case of c. perfringens infection in an adult with type 2 diabetes.201121628819
comparative genomics of four closely related clostridium perfringens bacteriophages reveals variable evolution among core genes with therapeutic potential.abstract: background: because biotechnological uses of bacteriophage gene products as alternatives to conventional antibiotics will require a thorough understanding of their genomic context, we sequenced and analyzed the genomes of four closely related phages isolated from clostridium perfringens, an important agricultural and human pathogen. results: phage whole-genome tetra-nucleotide signatures and proteomic tree topologies correlated closely with host phylogeny. comparisons of our phage geno ...201121631945
potential protective immunogenicity of recombinant clostridium perfringens α-β2-β1 fusion toxin in mice, sows and cows.clostridial toxins are main pathogenic virulence of clostridium perfringens that have been associated with a wide range of diseases in both humans and domestic animals. genetically engineered toxoids have been shown to function as potential vaccine candidates in the prevention of clostridium derived infectious diseases. in this study, we have developed recombinant α-toxin (cpa), β2/β1-fusion toxin (cpb2b1) and α/β2/β1 trivalent fusion-toxin (cpab2b1) as vaccine candidates that may be used to vac ...201121641956
expression of a clostridium perfringens type iv pilin by neisseria gonorrhoeae mediates adherence to muscle cells.clostridium perfringens is an anaerobic, gram-positive bacterium that causes a range of diseases in humans, including lethal gas gangrene. we have recently shown that strains of c. perfringens move across the surface of agar plates using a unique type iv pili (tfp)-mediated social motility that had not been previously described. based on sequence homology to pilins in gram-negative bacteria, c. perfringens appears to have two pilin subunits, pila1 and pila2. structural prediction analysis indica ...201121646450
rapid label-free identification of mixed bacterial infections by surface plasmon resonance.abstract: background: early detection of mixed aerobic-anaerobic infection has been a challenge in clinical practice due to the phenotypic changes in complex environments. surface plasmon resonance (spr) biosensor is widely used to detect dna-dna interaction and offers a sensitive and label-free approach in dna research. methods: in this study, we developed a single-stranded dna (ssdna) amplification technique and modified the traditional spr detection system for rapid and simultaneous detection ...201121649913
identification of novel clostridium perfringens type e strains that carry an iota toxin plasmid with a functional enterotoxin gene.clostridium perfringens enterotoxin (cpe) is a major virulence factor for human gastrointestinal diseases, such as food poisoning and antibiotic associated diarrhea. the cpe-encoding gene (cpe) can be chromosomal or plasmid-borne. recent development of conventional pcr cpe-genotyping assays makes it possible to identify cpe location (chromosomal or plasmid) in type a isolates. initial studies for developing cpe genotyping assays indicated that all cpe-positive strains isolated from sickened pati ...201121655254
claudin-4-targeted therapy using clostridium perfringens enterotoxin for prostate cancer.background: clostridium perfringens enterotoxin (cpe) triggers lysis of epithelial cells through binding to tight-junction proteins claudin-3 (cldn3) and cldn4, which are over-expressed in prostate cancer. we investigated the potential of cldn-targeted therapy using cpe. methods: we investigated the expression levels and subcellular localization of cldn3 and cldn4 in primary human prostate cancer tissues, human prostate cancer cell lines (22rv1, du145, and pc3) and normal human prostate epitheli ...201121656836
[spontaneous clostridium infection--often a post-mortem diagnosis].infections with clostridium species occur very seldom but then often as a lethal disease. they are mainly associated with trauma, surgery and malignancies, but can also occur with dermal and intestinal infections, burns and septic abortion. the development of gas gangrene is insidious and progression is very rapid. so it may stay unrealized until death and is often diagnosed only at autopsy.201121661254
clinicopathological and immunological studies on toxoids vaccine as a successful alternative in controlling clostridial infection in broilers.the present study was conducted to evaluate the efficacy and safety of three vaccination regimes of clostridium perfringens (c.-áperfringens) type a, c and combined a&c toxoids based on their clinical signs and immunological effects. the vaccines were administered two times at two weeks interval (7 & 21 days old), then the birds were challenged (35 days old) with virulent strains of c.-áperfringens type a, c and combined a&c. blood samples were taken one week after the first and second vaccinati ...201121664285
effects of land uses on fecal indicator bacteria in the water and soil of a tropical watershed.effects of different land uses on densities of escherichia coli, enterococci, and clostridium perfringens in the water and soil of a tropical watershed were investigated. densities of fecal indicator bacteria (fibs) in the watershed exhibited a clear land-use dependency in the stream water. significantly higher concentrations were detected in the urban portion of the stream (417, 420, and 44 cfu 100 ml(-1) for e. coli, enterococci, and c. perfringens, respectively) than in the forest portion (54 ...201121666390
[abscess formation after puncture of a thyroid cyst - a case report.]acute suppurative thyroiditis is a rarity and review of literature reveals a circumscript number of cases. a case of thyroid abscess formation after punction of a preexistent thyroid cyst is reported. microbiological examination detected the bacterium clostridium perfringens. the therapeutic approach is outlined in this report.ôçâ201121667445
mutated c-terminal fragments of clostridium perfringens enterotoxin have increased affinity to claudin-4 and reversibly modulate tight junctions in vitro.passage across epithelial cell sheets is the first step in drug absorption. tight junctions (tjs) are located between adjacent epithelial cells and seal the intercellular space preventing leakage of solutes. claudin, a tetra-transmembrane protein family, is a pivotal functional and structural component of the tj barrier. modulation of the claudin-based tj seal is a strategy for mucosal drug absorption. we previously found that a claudin-4 binder, a c-terminal fragment of clostridium perfringens ...201121672529
avian necrotic enteritis: experimental models, host immunity, pathogenesis, risk factors, and vaccine development.the increasing trends of legislative restrictions and voluntary removal of antibiotic growth promoters worldwide has already affected, and will continue to affect, poultry production and animal health. necrotic enteritis (ne) is being considered among the most important infectious diseases in the current poultry production system globally, with an estimated annual economic loss of more than $2 billion, largely attributable to medical treatments and impaired growth performance. thus, there is an ...201121673152
clostron-mediated engineering of clostridium.the genus clostridium is a diverse assemblage of gram positive, anaerobic, endospore-forming bacteria. whilst certain species have achieved notoriety as important animal and human pathogens (e.g. clostridium difficile, clostridium botulinum, clostridium tetani, and clostridium perfringens), the vast majority of the genus are entirely benign, and are able to undertake all manner of useful biotransformations. prominent amongst them are those species able to produce the biofuels, butanol and ethano ...201121815105
evidence for a prepore stage in the action of clostridium perfringens epsilon toxin.clostridium perfringens epsilon toxin (etx) rapidly kills mdck ii cells at 37°c, but not 4°c. the current study shows that, in mdck ii cells, etx binds and forms an oligomeric complex equally well at 37°c and 4°c but only forms a pore at 37°c. however, the complex formed in mdck cells treated with etx at 4°c has the potential to form an active pore, since shifting those cells to 37°c results in rapid cytotoxicity. those results suggested that the block in pore formation at 4°c involves temperatu ...201121814565
necrotic enteritis in broilers: an updated review on the pathogenesis.clostridium perfringens-induced necrotic enteritis and related subclinical disease have become economically significant problems for the broiler industry. fortunately, scientific interest in this topic has grown: new c. perfringens virulence factors have been discovered and new insight gained about the pathogenesis of necrotic enteritis. it has been shown that alpha toxin, for a long time thought to be the key virulence factor, is not essential for the development of the disease. moreover, it is ...201121812711
a toxicological evaluation of a claudin modulator, the c-terminal fragment of clostridium perfringens enterotoxin, in mice.tight junctions (tjs) maintain cellular polarity between the apical and basolateral region of epithelial cells. claudin, a tetra-transmembrane protein, plays a pivotal role in the barrier function of tjs. we previously found that a claudin modulator, the c-terminal fragment of clostridium perfringens enterotoxin (c-cpe), may be a promising candidate for improving the mucosal absorption of drugs. c-cpe is a fragment of enterotoxin, and putative cpe claudin receptors are highly expressed in liver ...201121812332
clostridium perfringens tpel is expressed during sporulation.clostridium perfringenstpel belongs to the family of large clostridial toxins. although recent studies demonstrated the expression of tpel during vegetative growth nothing is known about tpel expression during sporulation. our current study demonstrated that tpel: (i) is also expressed during sporulation; (ii) expression is dependent on the master regulator of sporulation, spo0a, and the sporulation-specific sigma factor, sige; and (iii) is localized to the mother cell compartment of the sporula ...201121810463
physical, chemical and microbiological quality of ice used to cool drinks and foods in greece and its public health implications.ice used for direct human consumption or to preserve foods and cool down drinks can be contaminated with pathogenic microorganisms and may potentially become a vehicle for consumer's infection. to evaluate physical, chemical and microbiological quality of commercial ice and ice used for fish and seafood, 100 ice samples collected at 10 different retail points in the region of epirus were studied. the following microbiological parameters were determined: total coliforms, fecal coliforms, salmonel ...201121802520
humoral immunity and injection-site reactions in cattle vaccinated with a multivalent clostridial vaccine administered via subcutaneous injection or via transdermal needle-free injection.objective-to evaluate injection-site reactions and serum antibody titers in cattle vaccinated with a clostridial vaccine administered sc or via needle-free transdermal injection. animals-sixteen 11-to 12-month-old herefords. procedures-cattle in 2 groups were vaccinated on days 0 and 28 with a commercially available multivalent clostridial vaccine administered sc or transdermally injection sites and serum antibody titers were evaluated at several time points after vaccination. serum antibody tit ...201121801072
host serum factor triggers germination of clostridium perfringens spores lacking the cortex hydrolysis machinery.clostridium perfringens type a is the causative agent of a variety of histotoxic and enteric diseases. the ability of c. perfringens spores to germinate in vivo might be due to the presence of nutrient germinants in the host tissue and blood. in the current study, we investigated the ability of spores of c. perfringens wild-type and mutant strains to germinate in blood. results indicate that spores of all three surveyed c. perfringens wild-type isolates germinated better in blood than in brain h ...201121799201
the role of an early salmonella typhimurium infection as a predisposing factor for necrotic enteritis in a laboratory challenge model.necrotic enteritis (ne) caused by clostridium perfringens (cp) in poultry is an important bacterial disease in terms of economic implications. the disease is multifactorial and is invariably associated with predisposing factors. in the present experiments, we investigated the potential predisposing role of neonatal salmonella typhimurium (st) infection for ne-associated mortality in a laboratory challenge model. in two experiments, day-of-hatch chicks were randomly assigned to four groups: group ...201121793451
a rare case of secondary bacterial peritonitis from clostridium perfringens in an adult patient with noncirrhotic ascites and a krukenberg tumor: report of a case.secondary bacterial peritonitis, in comparison to spontaneous, presents with a surgically treatable intraabdominal source for infection such as a gastrointestinal perforation or abscess and is nearly always polymicrobial. we present a rare case of secondary bacterial peritonitis from clostridium perfringens in an adult patient with noncirrhotic ascites and a krukenberg tumor.201121785606
characterization of the ß?-crystallin domains of ß?-cat, a non-lens ß?-crystallin and trefoil factor complex, from the skin of the toad bombina maxima.ß?-cat is a naturally existing 72-kda complex of a non-lens ß?-crystallin (a-subunit, cat-a) and a trefoil factor (ß-subunit, cat-ß) that contains a non-covalently linked form of aß(2) and was isolated from the skin secretions of the toad bombina maxima. the n-terminal region of cat-a (cat-an, residues 1-170) contains two ß?-crystallin domains while the c-terminal region (cat-ac) has sequence homology to the membrane insertion domain of the clostridium perfringens epsilon toxin. to examine the b ...201121784123
cellular vacuolation induced by clostridium perfringens epsilon-toxin.the epsilon-toxin of clostridium perfringens forms a heptamer in the membranes of madin-darby canine kidney (mdck) cells, leading to cell death. here, we report that it caused the vacuolation of mdck cells. the toxin induced vacuolation in a dose- and time-dependent manner. the monomer of the toxin formed oligomers on lipid rafts in membranes of the cells. methyl-beta-cyclodextrin and peg4000 inhibited the vacuolation. epsilon-toxin was internalized into the cells. confocal microscopy revealed t ...201121781280
swimmer risk of gastrointestinal illness from exposure to tropical coastal waters impacted by terrestrial dry-weather runoff.this study used molecular methods to measure concentrations of four enteric viruses (adenovirus, enterovirus, norovirus gi, and norovirus gii) and fecal source tracking markers (human, ruminant, and pig bacteroidales) in land-based runoff from 22 tropical streams on o'ahu, hawai'i. each stream was sampled twice in the morning and afternoon during dry weather. viruses and human bacteroidales were widespread in the streams. watershed septic tank densities were positively associated with higher occ ...201121780808
pathogenic bacteria in sewage treatment plants as revealed by 454 pyrosequencing.this study applied 454 high-throughput pyrosequencing to analyze potentially pathogenic bacteria in activated sludge from 14 municipal wastewater treatment plants (wwtps) across four countries (china, u.s., canada, and singapore), plus the influent and effluent of one of the 14 wwtps. a total of 370?870 16s rrna gene sequences with average length of 207 bps were obtained and all of them were assigned to corresponding taxonomic ranks by using rdp classifier and megan. it was found that the most a ...201121780772
[antimicrobial activity of bacteriocin s760 produced by enterococcus faecium strain lwp760].antimicrobial activity of bacteriocin s760 (enterocin) produced by enterococcusfaecium strain lwp760 was studied. bacteriocin s760 is a cationic, hydrophobic, and heat stable peptide with the molecular weight of 5.5 kda and pl of 9.8. enterocin s760 is shown to inhibit in vitro the growth both of sensitive and resistant to antibacterials gramnegative and grampositive bacteria of 25 species. mics of the bacteriocin s760 vary between 0.05-1.6 mg/l for escherichia coli 0157:h117, salmonella typhimu ...201121780664
colostrum and amniotic fluid from different species exhibit similar immunomodulating effects in bacterium-stimulated dendritic cells.the fetus and newborn are immunologically immature. bioactive compounds in amniotic fluid (af) and maternal milk therefore play a key role in the immunological development of the infant intestine. we hypothesized that colostrum and af exert similar immunomodulatory effects on the developing immune system. hence, bone marrow-derived murine dendritic cells (bmdcs) were co-incubated with clostridium perfringens a or escherichia coli nissle 1917 and porcine, bovine, or human af, colostrum/milk whey ...201121777143
membrane translocation of binary actin-adp-ribosylating toxins from clostridium difficile and clostridium perfringens is facilitated by cyclophilin a and hsp90.some hypervirulent strains of clostridium difficile produce the binary actin-adp-ribosylating toxin cdt in addition to the rho-glucosylating toxins a and b. it has been suggested that the presence of cdt increases the severity of the c. difficile-associated diseases including pseudomembranous colitis. cdt contains a binding and translocation component cdtb, which mediates the transport of the separate enzyme component cdta into the cytosol of target cells, where cdta modifies actin. here, we hav ...201121768281
etiologic agents and diseases found associated with clinical aspergillosis in falcons.the aim of this study was to describe parasitological, microbiological, and pathological findings associated with the isolation of aspergillus species in 94?clinically diseased captive falcons from dubai. concomitant agents and/or diseases were identified in 64?cases, causing either single (n = 36) or multiple coinfections (n = 28). diagnoses found more often in association with aspergillosis were chronic fatigue and immune dysfunction syndrome (cfids) (n = 29), caryospora sp. (n = 16), serratos ...201121754937
molecular typing of clostridium perfringens toxins recovered from central saudi arabia.this study reports on comparisons between polymerase chain reaction (pcr) and conventional diagnostic methods for typing clostridium perfringens toxins collected from central saudi arabia.201121748201
induction of neurite-outgrowth in pc12 cells by alpha-toxin from clostridium perfringens.alpha-toxin-induced phosphorylation of pdk1 via the tyrosine kinase a (trka) receptor signaling pathway plays an important role in the activation of rabbit neutrophils. the relation between the toxin and trka, however, remains poorly understood. here, we show that the toxin-induced phosphorylation of trka is closely related to the induction of neurite-outgrowth in pc12 cells. the toxin induced neurite-outgrowth and phosphorylation of trka in the cells in a dose-dependent manner. k252a, a trka in ...201121740889
efficient inhibition of germination of coat-deficient bacterial spores by multivalent metal cations, including terbium (tb3+).release of dipicolinic acid (dpa) and its fluorescence with terbium (tb(3+)) allow rapid measurement of the germination and viability of spores of bacillus and clostridium species. however, germination of coat-deficient bacillus spores was strongly inhibited by tb(3+) and some other multivalent cations. tb(3+) also inhibited germination of coat-deficient clostridium perfringens spores.201121685163
unexpected wide substrate specificity of c. perfringens +¦-toxin phospholipase c.clostridium perfringens phospholipase c (cpplc), also called +¦-toxin, is the main virulence factor for gas gangrene in humans. the lipase activity serves the bacterium to generate lipid signals in the host eukaryotic cell, and ultimately to degrade the host cell membranes. several previous reports indicated that cpplc was specific for phosphatidylcholine and sphingomyelin. molecular docking studies described in this paper predict favorable interactions of the cpplc active site with other phosph ...201121704605
interactions between clostridium perfringens enterotoxin and claudins.clostridium perfringens enterotoxin (cpe), a single polypeptide of approximately 35 kda in size, is -associated with type a food poisoning and such non-foodborne gastrointestinal diseases as antibiotic-associated diarrhea and sporadic diarrhea. cpe action begins with binding of the toxin to a claudin -receptor, forming a ôê+90 kda small complex that then rapidly oligomerizes into a hexamer of ôê+450 kda termed ch-1 (cpe hexamer-1). ch-1 is essentially a pore through which calcium gains entry to ...201121717349
epidemiology of food-borne disease outbreaks in the french armed forces: a review of investigations conducted from 1999 to 2009.objective: aim of this study was to describe the main characteristics of food-borne disease outbreaks (fbdos) in the french armed forces from 1999 to 2009. methods: fbdos are reported to the military epidemiological surveillance system, which concerns all active military personnel. investigation reports published from 1999 to 2009 were reviewed. results: among the 180 fbdos reported, 48.3% occurred overseas. the mean reporting rate was 2.4 outbreaks p.100,000 in france and 26.7 p.100,000 oversea ...201121840337
inhibitory effects of nisin against clostridium perfringens food poisoning and nonfood-borne isolates.the enterotoxigenic clostridium perfringens type a is the causative agent of c. perfringens type a food poisoning (fp) and nonfood-borne (nfb) human gastrointestinal diseases. due to its ability to form highly resistant endospores, it has become a great concern to the meat industry to produce meat free of c. perfringens. in this study, we evaluated the antimicrobial effect of nisin against c. perfringens fp and nfb isolates. no inhibitory effect of nisin was observed against germination of spore ...201122132724
effects of clostridium perfringens alpha and epsilon toxins in the bovine gut.clostridium perfringens alpha and epsilon toxins produce enterotoxaemia in sheep and goats. however, the information regarding the pathophysiology of alpha and epsilon toxins in the bovine intestine is still scanty. in this study, intestinal loops were performed in the ileum and colon of three one-week-old holstein and two four-week-old crossbreed calves. laparotomy was performed in all calves under anaesthesia and four loops -three cm long- were performed in the small and large intestines. for ...201122178571
epsilon-toxin production by clostridium perfringens type d strain cn3718 is dependent upon the agr operon but not the virs/virr two-component regulatory system.clostridium perfringens type b and d strains cause enterotoxemias and enteritis in livestock after proliferating in the intestines and producing epsilon-toxin (etx), alpha-toxin (cpa), and, usually, perfringolysin o (pfo). although etx is one of the most potent bacterial toxins, the regulation of etx production by type b or d strains remains poorly understood. the present work determined that the type d strain cn3718 upregulates production of etx upon close contact with enterocyte-like caco-2 ce ...201122167225
structural analysis of a bacterial exo-α-d-n-acetylglucosaminidase in complex with an unusual disaccharide found in class iii mucin.cpgh89 is a family 89 glycoside hydrolase with exo-α-d-n-acetylglucosaminidase activity that is produced by the human and animal pathogen clostridium perfringens. this enzyme is active on the α-d-glcpnac-(1→4)-d-galp motif that is expressed on the class iii mucins within the gastric mucosa. other members of this enzyme family, such as human naglu, are active on heparan. a truncated version of cpgh89 was rendered inactive through mutation of two key catalytic residues, the protein crystallized an ...201122090394
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