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spirotetronate antibiotics with anti-clostridium activity from actinomadura sp. 2eps.the rare actinomycetes strain 2eps was isolated from soil and analysis of cultural, morphological characteristics, diaminopimelic acid content of its cell wall, and 16s rrna gene sequence indicates that 2eps belongs to genus actinomadura. in addition, neighbor-joining phylogenetic tree also confirmed the relationships of this strain to other members of actinomadura. a butanol extract with antibacterial activity was purified by reversed-phase chromatography to obtain three bioactive compounds, de ...201525543910
effect of packaging technology on microbiological and sensory quality of a cooked blood sausage, morcela de arroz, from monchique region of portugal.morcela de arroz (ma), a popular portuguese blood sausage, with high ph and water activity (aw), is traditionally commercialized without preservatives and unpacked. this study evaluated the best packaging solution to extend ma shelf life stored at 4±1°c for 44days: without packaging (wp), vacuum (vp) and modified atmosphere packaging (map) (80% co2; 20% n2). mesophilic (mtvc), psychrotrophic (ptvc), lactic acid bacteria (lab), pseudomonads, molds and yeasts, enterobacteriaceae, listeria monocyto ...201525462380
characterization of clostridium perfringens tpel toxin gene carriage, production, cytotoxic contributions, and trypsin sensitivity.large clostridial toxins (lcts) are produced by at least four pathogenic clostridial species, and several lcts are proven pivotal virulence factors for both human and veterinary diseases. tpel is a recently identified lct produced by clostridium perfringens that has received relatively limited study. in response, the current study surveyed carriage of the tpel gene among different c. perfringens strains, detecting this toxin gene in some type a, b, and c strains but not in any type d or e strain ...201525824828
diet is a major factor governing the fecal butyrate-producing community structure across mammalia, aves and reptilia.butyrate-producing bacteria have an important role in maintaining host health. they are well studied in human and medically associated animal models; however, much less is known for other vertebrata. we investigated the butyrate-producing community in hindgut-fermenting mammalia (n = 38), aves (n = 8) and reptilia (n = 8) using a gene-targeted pyrosequencing approach of the terminal genes of the main butyrate-synthesis pathways, namely butyryl-coa:acetate coa-transferase (but) and butyrate kinas ...201525343515
in vitro antibacterial activity of thymol and carvacrol and their effects on broiler chickens challenged with clostridium perfringens.in the post-antibiotic era, essential oils (eo) are promising alternatives to growth-promoting antibiotics. the aim of the present study was to investigate the antibacterial activities of an eo product and its components thymol and carvacrol in vitro, and the efficacy of eo to control clostridium perfringens challenge in broiler chickens.201526705471
epidemiological and pathobiological profiles of clostridium perfringens infections: review of consecutive series of 33 cases over a 13-year period.although clostridium perfringens (c. perfringens) is well known as the causative agent of several forms of enteric disease, precise epidemiological and pathobiological aspects are still unknown.201525755747
hygienisation and nutrient conservation of sewage sludge or cattle manure by lactic acid fermentation.manure from animal farms and sewage sludge contain pathogens and opportunistic organisms in various concentrations depending on the health of the herds and human sources. other than for the presence of pathogens, these waste substances are excellent nutrient sources and constitute a preferred organic fertilizer. however, because of the pathogens, the risks of infection of animals or humans increase with the indiscriminate use of manure, especially liquid manure or sludge, for agriculture. this p ...201525786255
functional analysis of a bacitracin resistance determinant located on icecp1, a novel tn916-like element from a conjugative plasmid in clostridium perfringens.bacitracins are mixtures of structurally related cyclic polypeptides with antibiotic properties. they act by interfering with the biosynthesis of the bacterial cell wall. in this study, we analyzed an avian necrotic enteritis strain of clostridium perfringens that was resistant to bacitracin and produced netb toxin. we identified a bacitracin resistance locus that resembled a bacitracin resistance determinant from enterococcus faecalis. it contained the structural genes bcrabd and a putative reg ...201526282424
dna sequence signatures for rapid detection of six target bacterial pathogens using pcr assays.using streptococcus pyogenes as a model, we previously established a stepwise computational workflow to effectively identify species-specific dna signatures that could be used as pcr primer sets to detect target bacteria with high specificity and sensitivity. in this study, we extended the workflow for the rapid development of pcr assays targeting enterococcus faecalis, enterococcus faecium, clostridium perfringens, clostridium difficile, clostridium tetani, and staphylococcus aureus, which are ...201526279626
multiplex detection of nine food-borne pathogens by mpcr and capillary electrophoresis after using a universal pre-enrichment medium.routine microbiological quality analyses in food samples require, in some cases, an initial incubation in pre-enrichment medium. this is necessary in order to ensure that small amounts of pathogenic strains are going to be detected. in this work, a universal pre-enrichment medium has been developed for the simultaneous growth of bacillus cereus, campylobacter jejuni, clostridium perfringens, cronobacter sakazakii, escherichia coli, enterobacteriaceae family (38 species, 27 genera), listeria mono ...201526579100
loss of endothelial barrier antigen immunoreactivity as a marker of clostridium perfringens type d epsilon toxin-induced microvascular damage in rat brain.the epsilon toxin elaborated by clostridium perfringens type d in the intestine of domestic livestock is principally responsible for the neurological disease produced after its absorption in excessive quantities into the systemic circulation. the fundamental basis of the cerebral damage induced by epsilon toxin appears to be microvascular injury with ensuing severe, diffuse vasogenic oedema. endothelial barrier antigen (eba), which is normally expressed by virtually all capillaries and venules i ...201524973988
comparative neuropathology of ovine enterotoxemia produced by clostridium perfringens type d wild-type strain cn1020 and its genetically modified derivatives.clostridium perfringens type d causes enterotoxemia in sheep and goats. the disease is mediated by epsilon toxin (etx), which affects the cerebrovascular endothelium, increasing vascular permeability and leading to cerebral edema. in the present study, we compared the distribution and severity of the cerebrovascular changes induced in lambs by c. perfringens type d strain cn1020, its isogenic etx null mutant, and the etx-producing complemented mutant. we also applied histochemical and immunohist ...201524964921
hygienization performances of innovative sludge treatment solutions to assure safe land spreading.the present research aims at the evaluation of the hygienization performances of innovative sludge treatment processes applied for the separated treatment of secondary sludge. namely, two digestion pretreatments (sonication and thermal hydrolysis) and two sequential biological processes (mesophilic/thermophilic and anaerobic/aerobic digestion) were compared to the mesophilic (mad) and thermophilic anaerobic digestion (tad). microbial indicators (escherichia coli, somatic coliphages and clostridi ...201525233915
epsilon toxin from clostridium perfringens acts on oligodendrocytes without forming pores, and causes demyelination.epsilon toxin (et) is produced by clostridium perfringens types b and d and causes severe neurological disorders in animals. et has been observed binding to white matter, suggesting that it may target oligodendrocytes. in primary cultures containing oligodendrocytes and astrocytes, we found that et (10(-9) m and 10(-7) m) binds to oligodendrocytes, but not to astrocytes. et induces an increase in extracellular glutamate, and produces oscillations of intracellular ca(2+) concentration in oligoden ...201525287162
clostridium perfringens type a-e toxin plasmids.clostridium perfringens relies upon plasmid-encoded toxin genes to cause intestinal infections. these toxin genes are associated with insertion sequences that may facilitate their mobilization and transfer, giving rise to new toxin plasmids with common backbones. most toxin plasmids carry a transfer of clostridial plasmids locus mediating conjugation, which likely explains the presence of similar toxin plasmids in otherwise unrelated c. perfringens strains. the association of many toxin genes wi ...201525283728
regulation of toxin gene expression in clostridium perfringens.the gram-positive, anaerobic, spore-forming, rod-shaped clostridium perfringens is widely distributed in nature, especially in soil and the gastrointestinal tract of humans and animals. c. perfringens causes clostridial myonecrosis (or gas gangrene), enteritis and enterotoxemia in humans and livestock by producing numerous extracellular toxins and enzymes. the toxin gene expression is regulated by a two-component regulatory system and regulatory rna virr/virs-vr-rna cascade. the virr/virs system ...201525303832
a combination of targeted toxin technology and the piggybac-mediated gene transfer system enables efficient isolation of stable transfectants in nonhuman mammalian cells.isolation of cells harboring exogenous dna is typically achieved by the introduction of plasmids, but its efficiency remains still low. in this study, we developed a novel strategy to obtain stable transfectants efficiently. porcine embryonic fibroblasts were transfected with two plasmids: (i) ptransiend, which comprises the ubiquitous promoter, the piggybac (pb) transposase gene, an internal ribosomal entry site, the clostridium perfringens-derived endo-β-galactosidase c (endogalc) gene, and a ...201525345906
directed structural modification of clostridium perfringens enterotoxin to enhance binding to claudin-5.clostridium perfringens enterotoxin (cpe) binds to distinct claudins (clds), which regulate paracellular barrier functions in endo- and epithelia. the c-terminal domain (ccpe) has the potential for selective claudin modulation, since it only binds to a subset of claudins, e.g., cld3 and cld4 (ccpe receptors). cld5 (non-cpe receptor) is a main constituent in tight junctions (tj) of the blood-brain barrier. we aimed to reveal claudin recognition mechanisms of ccpe and to create a basis for a cld5- ...201525342221
clostridium perfringens endophthalmitis after penetrating keratoplasty with contaminated corneal allografts: a case series.to report the postoperative clinical course of 3 patients who underwent corneal transplantation with corneal allografts contaminated with clostridium perfringens and to evaluate the risk factors for anaerobic contamination in 2 donors.201525393093
dietary sodium selenite affects host intestinal and systemic immune response and disease susceptibility to necrotic enteritis in commercial broilers.1. this study was to evaluate the effects of supplementary dietary selenium (se) given as sodium selenite on host immune response against necrotic enteritis (ne) in commercial broiler chickens. 2. chicks were fed from hatching on a non-supplemented diet or diets supplemented with different levels of se (0.25, 0.50, and 1.00 se mg/kg). to induce ne, broiler chickens were orally infected with eimeria maxima at 14 d of age and then with clostridium perfringens 4 d later using our previously establi ...201525387235
sialidase production and genetic diversity in clostridium perfringens type a isolated from chicken with necrotic enteritis in brazil.the sialidase activity and genetic diversity of 22 clostridium perfringens strains isolated from chickens with necrotic enteritis were determined. sialidase activity was detected in 86.4 % of the strains. all c. perfringens showed a high value of similarity (>96 %), and they were grouped into seven clusters clearly separated from the other reference bacterial strains. from these clusters four patterns were defined in accordance with their phenotypic (sialidase production and antibiotic resistanc ...201525373329
determination of the clostridium perfringens-binding site on fibronectin.the extracellular matrix protein fibronectin (fn) is known to bind to the surface of clostridium perfringens cells. fn is a disulfide-linked homodimer protein, with each fn polypeptide consisting of three types of repeating modules: 12 type i, 2 type ii, and 15-17 type iii modules. to determine the epitope on fn recognized by c. perfringens cells, anti-fn monoclonal antibodies (mabs) and various fn fragments (iii2-10, riii2-4, riii5-7, riii8, riii9, riii10) were employed. although two c. perfrin ...201525433150
one-carbon metabolic pathway rewiring in escherichia coli reveals an evolutionary advantage of 10-formyltetrahydrofolate synthetase (fhs) in survival under hypoxia.in cells, n(10)-formyltetrahydrofolate (n(10)-fthf) is required for formylation of eubacterial/organellar initiator trna and purine nucleotide biosynthesis. biosynthesis of n(10)-fthf is catalyzed by 5,10-methylene-tetrahydrofolate dehydrogenase/cyclohydrolase (fold) and/or 10-formyltetrahydrofolate synthetase (fhs). all eubacteria possess fold, but some possess both fold and fhs. however, the reasons for possessing fhs in addition to fold have remained unclear. we used escherichia coli, which n ...201525448816
genomic analyses of clostridium perfringens isolates from five toxinotypes.clostridium perfringens can be isolated from a range of environments, including soil, marine and fresh water sediments, and the gastrointestinal tracts of animals and humans. some c. perfringens strains have attractive industrial applications, e.g., in the degradation of waste products or the production of useful chemicals. however, c. perfringens has been most studied as the causative agent of a range of enteric and soft tissue infections of varying severities in humans and animals. host prefer ...201525445567
differential outgrowth potential of clostridium perfringens food-borne isolates with various cpe-genotypes in vacuum-packed ground beef during storage at 12°c.in the current study, the outgrowth of spores of 15 different food isolates of clostridium perfringens was evaluated in vacuum-packed ground beef during storage at 12°c and 25°c. this included enterotoxic strains carrying the gene encoding the cpe enterotoxin on the chromosome (c-cpe), on a plasmid (p-cpe) and cpe-negative strains. the 15 strains were selected from a larger group of strains that were first evaluated for their ability to sporulate in modified duncan-strong sporulating medium. spo ...201525461607
detection and molecular typing of clostridium perfringens isolates from beef, chicken and turkey meats.here we describe a study investigating the presence of clostridium perfringens strains in meat samples and the toxin genes in the isolates by pcr. this study, for the first time, demonstrated the presence of c. perfringens type e in turkey meats, while c. perfringens type c strains isolated from chicken meats.201525460196
microbial evaluation of sandboxes located in urban area.this paper presents the results of a study on the degree of bacteriological pollution of sandboxes situated in fenced and unfenced housing estates located in an urban area in olsztyn, poland. heterotrophic plate counts (hpc22, hpc37), enterobacteriaceae, escherichia coli, enterococcus spp., staphylococcus spp. and clostridium perfringens determined by cultivation and fluorescence in situ hybridization (fish) methods were used as indicators of the sanitary state. their maximum number in the sand ...201525483374
dynamic determination of kinetic parameters, computer simulation, and probabilistic analysis of growth of clostridium perfringens in cooked beef during cooling.the objective of this research was to develop a new one-step methodology that uses a dynamic approach to directly construct a tertiary model for prediction of the growth of clostridium perfringens in cooked beef. this methodology was based on simultaneous numerical analysis and optimization of both primary and secondary models using multiple dynamic growth curves obtained under different conditions. once the models were constructed, the bootstrap method was used to calculate the 95% confidence i ...201525500276
two novel membrane proteins, tcpd and tcpe, are essential for conjugative transfer of pcw3 in clostridium perfringens.the anaerobic pathogen clostridium perfringens encodes either toxin genes or antibiotic resistance determinants on a unique family of conjugative plasmids that have a novel conjugation region, the tcp locus. studies of the paradigm conjugative plasmid from c. perfringens, the 47-kb tetracycline resistance plasmid pcw3, have identified several tcp-encoded proteins that are involved in conjugative transfer and form part of the transfer apparatus. in this study, the role of the conserved hypothetic ...201525488300
interaction of clostridium perfringens epsilon-toxin with biological and model membranes: a putative protein receptor in cells.epsilon-toxin (etx) is a powerful toxin produced by some strains of clostridium perfringens (classified as types b and d) that is responsible for enterotoxemia in animals. etx forms pores through the plasma membrane of eukaryotic cells, consisting of a β-barrel of 14 amphipathic β-strands. etx shows a high specificity for certain cell lines, of which madin-darby canine kidney (mdck) is the first sensitive cell line identified and the most studied one. the aim of this study was to establish the r ...201525485476
evaluation of a membrane filtration method for the rapid enumeration of confirmed clostridium perfringens from water.a modification of the uk reference and iso 14189 tsca medium for the enumeration of clostridium perfringens from water coupled with a membrane filter transfer technique for testing for production of acid phosphatase was evaluated. the new tryptose cycloserine agar (tca) medium, which lacks sodium metabisulphite but contains sodium pyruvate to improve recovery, allows the isolation and confirmation of cl. perfringens within 18-24 h of sample processing. data from a multilaboratory study analysed ...201525514882
parasitic gastroenteritis in lambs widespread.parasitic gastroenteritis diagnosed in lambs by all veterinary investigation centres, clostridium perfringens epsilon enterotoxaemia suspected in two cows, comparative quarterly porcine reproductive and respiratory syndrome diagnoses reach a 10-year peak, failure of an entire colony of gulls in cumbria, endoparasitism the predominant feature in exotic farmed animals, these are among matters discussed in the animal and plant health agency's (apha's) disease surveillance report for september 2014.201525614548
identification of the replication region in pbcnf5603, a bacteriocin-encoding plasmid, in the enterotoxigenic clostridium perfringens strain f5603.most recent studies of clostridium perfringens plasmids have focused on toxin-encoding or antibiotic resistance plasmids. to cause intestinal disease, a toxigenic strain must grow in the intestines to levels allowing for sufficient toxin production and this in vivo growth often involves overcoming the normal intestinal microbial population. for this purpose, bacteriocin production might be important.201526055257
fatal clostridium perfringens septicemia suggested by postmortem computed tomography: a medico-legal autopsy case report.we report a fatal case of suspected clostridium (cl.) perfringens septicemia in a previously healthy woman in her eighties. at first, she presented at the hospital complaining of upper abdominal discomfort and vomiting, and was discharged the next day after ruling out any fatal conditions. however, her condition deteriorated approximately 10h after discharge and she died shortly after. the postmortem computed tomography (pmct) performed 29h postmortem revealed an excessive systemic gas accumulat ...201526048862
hydrolyzable and condensed tannins resistance in clostridium perfringens.tannins added in the diet are being used to improve nutrition and health in farm animals as an alternative to antibiotic growth promoters and to control enteric clostridial diseases. however, the capacity of clostridium perfringens to develop resistance under the selective pressure of tannins is unknown. the purpose of this study was to determine if c. perfringens possess the ability to develop resistance against tannins in comparison with antimicrobial agents. susceptibility for 7 agps (antimic ...201526037239
inflammatory responses to a clostridium perfringens type a strain and α-toxin in primary intestinal epithelial cells of chicken embryos.the causative pathogen of necrotic enteritis is the gram-positive bacterium clostridium perfringens. its main cell wall component, peptidoglycan (pgn), can be recognized by toll-like receptor 2 and nucleotide-binding oligomerization domain (nod). consequently, the immune response is initiated via activation of nuclear factor kappa b (nf-κb) signalling pathway. an in vitro study was conducted to investigate chicken intestinal inflammatory responses to c. perfringens type a and one of its virulenc ...201525584964
effects of dietary selenium on host response to necrotic enteritis in young broilers.the effects of dietary supplementation of young broiler chickens with an organic selenium (se) formulation, b-traxim se, on experimental necrotic enteritis (ne) were studied. chickens treated with three se doses (0.25, 0.50, 1.00 mg/kg) from hatch were orally challenged with eimeria maxima at 14 days of age followed by clostridium perfringens to induce ne. chickens fed with 0.50 mg/kg se showed significantly increased body weights and antibody levels against netb, and significantly reduced gut l ...201525575447
four foodborne disease outbreaks caused by a new type of enterotoxin-producing clostridium perfringens.the epidemiological and bacteriological investigations on four foodborne outbreaks caused by a new type of enterotoxin-producing clostridium perfringens are described. c. perfringens isolated from patients of these outbreaks did not produce any known enterotoxin and did not carry the c. perfringens enterotoxin gene. however, the culture filtrates of these isolates induced the accumulation of fluid in rabbit ileal loop tests. the molecular weight of the new enterotoxin may be between 50,000 and 1 ...201525568432
high stocking density as a predisposing factor for necrotic enteritis in broiler chicks.stocking density is a management factor which has critical implications for the poultry industry. the aim of the present study was to investigate the effect of high stocking density as a predisposing factor in an experimental model of necrotic enteritis in broiler chicks. the experimental challenge model included an oral inoculation with 10-fold dose of attenuated anticoccidial vaccine and multiple oral inoculations with a specific strain of clostridium perfringens. two hundred and forty as hatc ...201525563065
clinico-pathological findings of clostridium perfringens type d enterotoxaemia in goats and its hemolytic activity in different erythrocytes.the present investigation was conducted to study the effects of experimental clostridium perfringens type d enterotoxaemia in teddy goats. clinical signs started to appear after 30 min of experimental infection like anorexia, diarrhea, dehydration, frothing and dyspnea. gross lesions consisted of severe congestion in tissues of varying intensity with enlarged mesenteric lymph nodes while histological examination revealed edema of lungs, kidney, and lymph nodes and to some extent in brain along w ...201527175159
no difference in fecal levels of bacteria or short chain fatty acids in humans, when consuming fruit juice beverages containing fruit fiber, fruit polyphenols, and their combination.this study examined the effect of a boysenberry beverage (750 mg polyphenols), an apple fiber beverage (7.5 g dietary fiber), and a boysenberry plus apple fiber beverage (750 mg polyphenols plus 7.5 g dietary fiber) on gut health. twenty-five individuals completed the study. the study was a placebo-controlled crossover study, where every individual consumed 1 of the 4 treatments in turn. each treatment phase was 4-week long and was followed by a 2-week washout period. the trial beverages were 35 ...201525530011
cost-of-illness and disease burden of food-related pathogens in the netherlands, 2011.to inform risk management decisions on control and prevention of food-related disease, both the disease burden expressed in disability adjusted life years (daly) and the cost-of-illness of food-related pathogens are estimated and presented. disease burden of fourteen pathogens that can be transmitted by food, the environment, animals and humans was previously estimated by havelaar et al. (2012). in this paper we complement these by cost-of-illness estimates. together, these present a complete pi ...201525528537
tight junctions. structural insight into tight junction disassembly by clostridium perfringens enterotoxin.the c-terminal region of clostridium perfringens enterotoxin (c-cpe) can bind to specific claudins, resulting in the disintegration of tight junctions (tjs) and an increase in the paracellular permeability across epithelial cell sheets. here we present the structure of mammalian claudin-19 in complex with c-cpe at 3.7 å resolution. the structure shows that c-cpe forms extensive hydrophobic and hydrophilic interactions with the two extracellular segments of claudin-19. the claudin-19/c-cpe comple ...201525678664
complementary probes reveal that phosphatidylserine is required for the proper transbilayer distribution of cholesterol.cholesterol is an essential component of metazoan cellular membranes and it helps to maintain the structural integrity and fluidity of the plasma membrane. here, we developed a cholesterol biosensor, termed d4h, based on the fourth domain of clostridium perfringens theta-toxin, which recognizes cholesterol in the cytosolic leaflet of the plasma membrane and organelles. the d4h probe disassociates from the plasma membrane upon cholesterol extraction and after perturbations in cellular cholesterol ...201525663704
recent insights into clostridium perfringens beta-toxin.clostridium perfringens beta-toxin is a key mediator of necrotizing enterocolitis and enterotoxemia. it is a pore-forming toxin (pft) that exerts cytotoxic effect. experimental investigation using piglet and rabbit intestinal loop models and a mouse infection model apparently showed that beta-toxin is the important pathogenic factor of the organisms. the toxin caused the swelling and disruption of hl-60 cells and formed a functional pore in the lipid raft microdomains of sensitive cells. these f ...201525654787
immunization with recombinant bivalent chimera r-cpae confers protection against alpha toxin and enterotoxin of clostridium perfringens type a in murine model.clostridium perfringens type a, an anaerobic pathogen is the most potent cause of soft tissue infections like gas gangrene and enteric diseases like food poisoning and enteritis. the disease manifestations are mediated via two important exotoxins, viz. myonecrotic alpha toxin (αc) and enterotoxin (cpe). in the present study, we synthesized a bivalent chimeric protein r-cpae comprising c-terminal binding regions of αc and cpe using structural vaccinology rationale and assessed its protective effi ...201525645504
clostridium perfringens: a review of enteric diseases in dogs, cats and wild animals.clostridium perfringens is a gram-positive anaerobic bacillus that is commonly part of the microbiota of humans and animals. it is considered a common enteric pathogen, but the pathogenesis and the predisposing factors of the disease commonly differ between host species. thus, specific research is necessary to understand the role of this pathogen, how to diagnose it, and which control measures are applicable. the aim of this paper is to review the current knowledge of c. perfringens infections i ...201525644183
identification and characterization of clostridium perfringens beta toxin variants with differing trypsin sensitivity and in vitro cytotoxicity activity.by producing toxins, clostridium perfringens causes devastating diseases of both humans and animals. c. perfringens beta toxin (cpb) is the major virulence determinant for type c infections and is also implicated in type b infections, but little is known about the cpb structure-function relationship. amino acid sequence comparisons of the cpbs made by 8 randomly selected isolates identified two natural variant toxins with four conserved amino acid changes, including a switch of e to k at positio ...201525643999
an assessment of the human health impact of seven leading foodborne pathogens in the united states using disability adjusted life years.we explored the overall impact of foodborne disease caused by seven leading foodborne pathogens in the united states using the disability adjusted life year (daly). we defined health states for each pathogen (acute illness and sequelae) and estimated the average annual incidence of each health state using data from public health surveillance and previously published estimates from studies in the united states, canada and europe. these pathogens caused about 112 000 dalys annually due to foodborn ...201525633631
correction for chen et al., 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. 201525626909
identification of tyrosine 71 as a critical residue for the cytotoxic activity of clostridium perfringens epsilon toxin towards mdck cells.clostridium perfringens epsilon toxin (etx) is an extremely potent toxin, causing fatal enterotoxaemia in many animals. several amino acids in domains i and ii have been proposed to be critical for etx to interact with mdck cells. however, the critical amino acids in domain iii remain undefined. therefore, we assessed the effects of aromatic amino acids in domain iii on etx activity in this study. all of the results indicated that y71 was critical for the cytotoxic activity of etx towards mdck c ...201525626370
rye affects bacterial translocation, intestinal viscosity, microbiota composition and bone mineralization in turkey poults.previously, we have reported that rye significantly increased both viscosity and clostridium perfringens proliferation when compared with corn in an in vitro digestive model. two independent trials were conducted to evaluate the effect of rye as a source of energy on bacterial translocation, intestinal viscosity, gut microbiota composition, and bone mineralization, when compared with corn in turkey poults. in each experiment, day-of-hatch, turkey poults were randomly assigned to either a corn or ...201525849537
claudin-4 spect imaging allows detection of aplastic lesions in a mouse model of breast cancer.the expression of claudin-4, a protein involved in tight junction complexes, is widely dysregulated in epithelial malignancies. claudin-4 is overexpressed in several premalignant precursor lesions, including those of cancers of the breast, pancreas, and prostate, and is associated with poor survival. a noncytotoxic c-terminal fragment of clostridium perfringens enterotoxin (ccpe) is a natural ligand for claudin-4. here, we demonstrate whole-body quantitative spect imaging of preneoplastic breast ...201525840973
bacterial enteritis in ostrich (struthio camelus) chicks in the western cape province, south africa.ostrich (struthio camelus) chicks less than 3 mo age are observed to experience a high mortality rate that is often associated with enteritis. this study was undertaken to investigate the infectious bacteria implicated in ostrich chick enteritis. postmortems were performed on 122 ostrich chicks aged from 1 d to 3 mo and intestinal samples were subjected to bacterial culture. bacterial isolates were typed by pcr and serotyping. escherichia coli (e. coli; 49%) was the most frequently isolated from ...201525840967
characterization of clostridium perfringens isolates obtained from 2010 to 2012 from chickens with necrotic enteritis in korea.clostridium perfringens produces diverse virulent toxins that cause necrotic enteritis in poultry, resulting in a great negative impact on the poultry industry. to study the characteristics of c. perfringens in chickens, we isolated 88 strains from chickens (1 strain per flock) with necrotic enteritis. the isolated bacterial strains were screened for toxin type and antimicrobial susceptibility. necropsy of 17 chickens that died from necrotic enteritis revealed that their intestines were dilated ...201525840962
clostridium perfringens enterotoxin (cpe) and cpe-binding domain (c-cpe) for the detection and treatment of gynecologic cancers.clostridium perfringens enterotoxin (cpe) is a three-domain polypeptide, which binds to claudin-3 and claudin-4 with high affinity. because these receptors are highly differentially expressed in many human tumors, claudin-3 and claudin-4 may provide an efficient molecular tool to specifically identify and target biologically aggressive human cancer cells for cpe-specific binding and cytolysis. in this review we will discuss these surface proteins as targets for the detection and treatment of che ...201525835384
focal bacterial meningitis following ascending bite wound infection leading to paraparesis in a captive california sea lion (zalophus californianus).magnetic resonance imaging was performed on a 15-yr-old captive female california sea lion (zalophus californianus) with a 2-wk history of progressive paraparesis and a 9-mo history of exudative skin lesion on the left thoracic wall. magnetic resonance images showed a well-defined muscle infiltrating lesion ventrolateral to the seventh cervical to the third thoracic vertebra on the left side, which extended through the left intervertebral foramina c7 to t3 into the vertebral canal, causing spina ...201525831587
the cpal quorum sensing system regulates production of hemolysins cpa and pfo to build clostridium perfringens biofilms.clostridium perfringens strains produce severe diseases, including myonecrosis and enteritis necroticans, in humans and animals. diseases are mediated by the production of potent toxins that often damage the site of infection, e.g., skin epithelium during myonecrosis. in planktonic cultures, the regulation of important toxins, such as cpa, cpb, and pfo, is controlled by the c. perfringens agr-like (cpal) quorum sensing (qs) system. strains also encode a functional luxs/ai-2 system. although c. p ...201525824838
multi-organ failure secondary to a clostridium perfringens gaseous liver abscess following a self-limited episode of acute gastroenteritis.clostridium perfringens is an unusual pathogen responsible for the development of a gas-forming pyogenic liver abscess. progression to septicemia with this infection has amplified case fatality rates.201525807198
effect of lactobacillus plantarum strain k21 on high-fat diet-fed obese mice.recent studies have demonstrated beneficial effects of specific probiotics on alleviating obesity-related disorders. here we aimed to identify probiotics with potential antiobesity activity among 88 lactic acid bacterial strains via in vitro screening assays, and a lactobacillus plantarum strain k21 was found to harbor abilities required for hydrolyzing bile salt, reducing cholesterol, and inhibiting the accumulation of lipid in 3t3-l1 preadipocytes. furthermore, effects of k21 on diet-induced o ...201525802537
clostridium perfringens type e virulence traits involved in gut colonization.clostridium perfringens type e disease in ruminants has been characterized by hemorrhagic enteritis or sudden death. although type e isolates are defined by the production of alpha and iota toxin, little is known about the pathogenesis of c. perfringens type e infections. thus far, the role of iota toxin as a virulence factor is unknown. in this report, iota toxin showed positive effects on adherence and colonization of c. perfringens type e while having negative effect on the adherence of type ...201525799452
the inhibitory effects of sorbate and benzoate against clostridium perfringens type a isolates.this study evaluated the inhibitory effects of sorbate and benzoate against clostridium perfringens type a food poisoning (fp) and non-food-borne (nfb) disease isolates. no significant inhibition of germination of spores of both fp and nfb isolates was observed in rich medium (ph 7.0) supplemented with permissive level of sodium sorbate (0.3% ≈ 0.13 mm undissociated sorbic acid) or sodium benzoate (0.1% ≈ 0.01 mm undissociated benzoic acid) used in foods. however, these levels of sorbate and ben ...201525790996
phytase modulates ileal microbiota and enhances growth performance of the broiler chickens.phytase is well studied and explored, however, little is known about its effects on the microbial ecology of the gastrointestinal tract. in total, 400 one-day-old female ross 308 chicks were randomly distributed to four experimental groups. the dietary treatments were arranged as a 2 × 2 complete factorial design, with the factors being adequate (pc) or insufficient calcium (ca) and digestible phosphor (dp)(nc) and with or without 5000 phytase units (ftu)/kg of escherichia coli 6-phytase. the ga ...201525781608
structure-function analysis of peptide signaling in the clostridium perfringens agr-like quorum sensing system.the accessory growth regulator (agr)-like quorum sensing (qs) system of clostridium perfringens controls the production of many toxins, including beta toxin (cpb). we previously showed (j. e. vidal, m. ma, j. saputo, j. garcia, f. a. uzal, and b. a. mcclane, mol microbiol 83:179-194, 2012, http://dx.doi.org/10.1111/j.1365-2958.2011.07925.x) that an 8-amino-acid, agrd-derived peptide named 8-r upregulates cpb production by this qs system. the current study synthesized a series of small signaling ...201525777675
animal models to study the pathogenesis of human and animal clostridium perfringens infections.the most common animal models used to study clostridium perfringens infections in humans and animals are reviewed here. the classical c. perfringens-mediated histotoxic disease of humans is clostridial myonecrosis or gas gangrene and the use of a mouse myonecrosis model coupled with genetic studies has contributed greatly to our understanding of disease pathogenesis. similarly, the use of a chicken model has enhanced our understanding of type a-mediated necrotic enteritis in poultry and has led ...201525770894
clostridial co-infection episodes in commercial laying hens.the present report describes two outbreaks of serious enteritis in commercial laying hens where clostridium perfringens and clostridium colinum were simultaneously detected. at the age of 44 and 31 weeks, two laying hen flocks showed an increase of the mortality rate and a worsening of productive performance. post-mortem examination revealed intestinal necrotic-haemorrhagic ulcerations and hepatic focal necrosis. the bacteriological examination yielded the isolation of c. colinum and c. perfring ...201525769045
health risk assessment related to waterborne pathogens from the river to the tap.a two-year monitoring program of cryptosporidium parvum oocysts, giardia duodenalis cysts, escherichia coli, clostridium perfringens spores and adenovirus was conducted in three large rivers in france used for recreational activities and as a resource for drinking water production. fifty-liter river water and one thousand-liter tap water samples were concentrated using hollow-fiber ultrafiltration and analyzed by molecular biology or laser-scanning cytometry. in order to evaluate watershed land ...201525764059
use of yeast cell wall extract as a tool to reduce the impact of necrotic enteritis in broilers.the use of a yeast cell wall extract derived from saccharomyces cerevisiae (actigen(®)) has been proposed as an alternative to in-feed antibiotics. this experiment was conducted to investigate the efficacy of yeast cell extract as an alternative to zinc bacitracin or salinomycin using a necrotic enteritis challenge model. a feeding study was conducted using 480-day-old male ross 308 chicks assigned to 48 floor pens. a 2 × 4 factorial arrangement of treatments was employed. the factors were: chal ...201525762162
an allosteric model for control of pore opening by substrate binding in the eutl microcompartment shell protein.the ethanolamine utilization (eut) microcompartment is a protein-based metabolic organelle that is strongly associated with pathogenesis in bacteria that inhabit the human gut. the exterior shell of this elaborate protein complex is composed from a few thousand copies of bmc-domain shell proteins, which form a semi-permeable diffusion barrier that provides the interior enzymes with substrates and cofactors while simultaneously retaining metabolic intermediates. the ability of this protein shell ...201525752492
[a case of freeze-dried gas gangrene antitoxin for the treatment of clostridium perfringens sepsis].a 66-year-old man was admitted to our hospital with high fever. we diagnosed a gas-containing liver abscess and performed percutaneous abscess drainage. however, 15 hours after admission, he developed massive intravascular hemolysis and acidosis. sepsis due to clostridium perfringens was suspected and we treated the patient intensively with multidisciplinary approaches, including antibiotics, mechanical ventilation, and renal replacement therapy. furthermore, we administered freeze-dried gas gan ...201525748160
loop-mediated isothermal amplification (lamp) assays for the species-specific detection of eimeria that infect chickens.eimeria species parasites, protozoa which cause the enteric disease coccidiosis, pose a serious threat to the production and welfare of chickens. in the absence of effective control clinical coccidiosis can be devastating. resistance to the chemoprophylactics frequently used to control eimeria is common and sub-clinical infection is widespread, influencing feed conversion ratios and susceptibility to other pathogens such as clostridium perfringens. despite the availability of polymerase chain re ...201525741643
microbial pathogens in wastewater treatment plants (wwtp) in hamburg.microbial pathogens are among the major health problems associated with water and wastewater. classical indicators of fecal contamination include total coliforms, escherichia coli, and clostridium perfringens. these fecal indicators were monitored in order to obtain information regarding their evolution during wastewater treatment processes. helminth eggs survive for a long duration in the environment and have a high potential for waterborne transmission, making them reliable contaminant indicat ...201525734765
a five site clostridium perfringens food-borne outbreak: a retrospective cohort study.in may of 2012, we investigated a food-borne clostridium perfringens outbreak in slovenia involving a single kitchen and five venues, with 477 exposed persons.201527646622
an internal thioester in a pathogen surface protein mediates covalent host binding.to cause disease and persist in a host, pathogenic and commensal microbes must adhere to tissues. colonization and infection depend on specific molecular interactions at the host-microbe interface that involve microbial surface proteins, or adhesins. to date, adhesins are only known to bind to host receptors non-covalently. here we show that the streptococcal surface protein sfbi mediates covalent interaction with the host protein fibrinogen using an unusual internal thioester bond as a 'chemica ...201526032562
lipoproteins from clostridium perfringens and their protective efficacy in mouse model.clostridium perfringens is an obligately anaerobic rod-shaped bacterium and etiological agent for several diseases in humans and animals. the pathogen has been listed as validated biological agent and warrants development of medical countermeasures. the homologs of some of the lipoproteins identified from various fractions of c. perfringens in our previous studies were observed to be virulence determinants in other pathogenic bacteria. three putative virulence associated lipoproteins; polysaccha ...201526027922
critical illness in pregnancy: part ii: common medical conditions complicating pregnancy and puerperium.the first of this two-part series on critical illness in pregnancy dealt with obstetric disorders. in part ii, medical conditions that commonly affect pregnant women or worsen during pregnancy are discussed. ards occurs more frequently in pregnancy. strategies commonly used in nonpregnant patients, including permissive hypercapnia, limits for plateau pressure, and prone positioning, may not be acceptable, especially in late pregnancy. genital tract infections unique to pregnancy include chorioam ...201526020727
c-terminal clostridium perfringens enterotoxin-mediated antigen delivery for nasal pneumococcal vaccine.efficient vaccine delivery to mucosal tissues including mucosa-associated lymphoid tissues is essential for the development of mucosal vaccine. we previously reported that claudin-4 was highly expressed on the epithelium of nasopharynx-associated lymphoid tissue (nalt) and thus claudin-4-targeting using c-terminal fragment of clostridium perfringens enterotoxin (c-cpe) effectively delivered fused antigen to nalt and consequently induced antigen-specific immune responses. in this study, we applie ...201526018248
perfringolysin o: the underrated clostridium perfringens toxin?the anaerobic bacterium clostridium perfringens expresses multiple toxins that promote disease development in both humans and animals. one such toxin is perfringolysin o (pfo, classically referred to as θ toxin), a pore-forming cholesterol-dependent cytolysin (cdc). pfo is secreted as a water-soluble monomer that recognizes and binds membranes via cholesterol. membrane-bound monomers undergo structural changes that culminate in the formation of an oligomerized prepore complex on the membrane sur ...201526008232
automated sampling procedures supported by high persistence of bacterial fecal indicators and bacteroidetes genetic microbial source tracking markers in municipal wastewater during short-term storage at 5°c.because of high diurnal water quality fluctuations in raw municipal wastewater, the use of proportional autosampling over a period of 24 h at municipal wastewater treatment plants (wwtps) to evaluate carbon, nitrogen, and phosphorus removal has become a standard in many countries. microbial removal or load estimation at municipal wwtps, however, is still based on manually recovered grab samples. the goal of this study was to establish basic knowledge regarding the persistence of standard bacteri ...201526002900
location and stoichiometry of the protease cspb and the cortex-lytic enzyme slec in clostridium perfringens spores.the protease cspb and the cortex-lytic enzyme slec are essential for peptoglycan cortex hydrolysis during germination of spores of the clostridium perfringens food poisoning isolate sm101. in this study, western blot analyses were used to demonstrate that cspb and slec are present exclusively in the c. perfringens sm101 spore coat layer fraction and absent in the lysate from decoated spores and from the purified inner spore membrane. these results indicate why decoating treatments greatly reduce ...201525998819
characterization, validation and application of a dna microarray for the detection of mandatory and other waterborne pathogens.culture methods for the detection of indicator bacteria are currently used for detection of waterborne bacteria. the need for an increased range of analyzed bacteria coupled with the obtainment of rapid and early results justify the development of a dna microarray for the identification of waterborne pathogens. this dna microarray has 16 implanted probes with a median size of 147 bases, targeting 12 different parameters, including all mandatory indicator microorganisms, such as escherichia coli, ...201525998249
the myelin and lymphocyte protein mal is required for binding and activity of clostridium perfringens ε-toxin.clostridium perfringens ε-toxin (etx) is a potent pore-forming toxin responsible for a central nervous system (cns) disease in ruminant animals with characteristics of blood-brain barrier (bbb) dysfunction and white matter injury. etx has been proposed as a potential causative agent for multiple sclerosis (ms), a human disease that begins with bbb breakdown and injury to myelin forming cells of the cns. the receptor for etx is unknown. here we show that both binding of etx to mammalian cells and ...201525993478
impact of mutating the key residues of a bifunctional 5,10-methylenetetrahydrofolate dehydrogenase-cyclohydrolase from escherichia coli on its activities.methylenetetrahydrofolate dehydrogenase-cyclohydrolase (fold) catalyzes interconversion of 5,10-methylene-tetrahydrofolate and 10-formyl-tetrahydrofolate in the one-carbon metabolic pathway. in some organisms, the essential requirement of 10-formyl-tetrahydrofolate may also be fulfilled by formyltetrahydrofolate synthetase (fhs). recently, we developed an escherichia coli strain in which the fold gene was deleted in the presence of clostridium perfringens fhs (e. coli δfold/p-fhs) and used it to ...201525988590
fate and transport of enteric microbes from septic systems in a coastal watershed.onsite wastewater treatment systems (owts) are commonly used in coastal areas to treat household wastewater. these systems represent potential sources of fecal pollution of groundwater and nearby surface water. owts are expected to reduce microbial concentrations in wastewater; however, system and environmental factors can affect treatment efficiency and impacts on ground and surface water. in the study of owts described in this article, the authors sampled septic tanks and groundwater at two ho ...201525985535
genome-wide transcriptional profiling of clostridium perfringens sm101 during sporulation extends the core of putative sporulation genes and genes determining spore properties and germination characteristics.the formation of bacterial spores is a highly regulated process and the ultimate properties of the spores are determined during sporulation and subsequent maturation. a wide variety of genes that are expressed during sporulation determine spore properties such as resistance to heat and other adverse environmental conditions, dormancy and germination responses. in this study we characterized the sporulation phases of c. perfringens enterotoxic strain sm101 based on morphological characteristics, ...201525978838
assembly and function of claudins: structure-function relationships based on homology models and crystal structures.the tetra-span transmembrane proteins of the claudin family are critical components of formation and function of tight junctions (tj). homo- and heterophilic side-by-side (cis) and intercellular head-to-head (trans) interactions of 27 claudin-subtypes regulate tissue-specifically the paracellular permeability and/or tightness between epithelial or endothelial cells. this review highlights the functional impact that has been identified for particular claudin residues by relating them to structura ...201525957516
impact of clean-label antimicrobials and nitrite derived from natural sources on the outgrowth of clostridium perfringens during cooling of deli-style turkey breast.organic acids and sodium nitrite have long been shown to provide antimicrobial activity during chilling of cured meat products. however, neither purified organic acids nor nano2 is permitted in products labeled natural and both are generally avoided in clean-label formulations; efficacy of their replacement is not well understood. natural and clean-label antimicrobial alternatives were evaluated in both uncured and in alternative cured (a process that uses natural sources of nitrite) deli-style ...201525951389
clostridium perfringens tpel induces formation of stress fibers via activation of rhoa-rock signaling pathway.clostridium perfringens tpel belongs to a family of large clostridial glucosylating cytotoxins. tpel modifies rac1 and ras subfamily proteins. herein we report tpel-induced formation of stress fibers via rhoa-rho kinase (rock) signaling. a recombinant protein (tpel1-525) derived from the tpel n-terminal catalytic domain in the presence of streptolysin o (slo) induced the formation of actin stress fibers in madin-darby canine kidney (mdck) cells in a dose-dependent manner. the rhoa/rock pathway i ...201525947919
recovery of staphylococcus aureus in gray mugil cephalus roe (bottarga): investigation by an integrated cultural/molecular approach.in the mediterranean area, salted and dried roe from the gray mugil cephalus "bottarga" represent a speciality food with great commercial value. bottarga is currently produced by a traditional handmade process and, the risk of human bacterial contamination during its manufacturing is still unknown; in this perspective the foodborne pathogen staphylococcus aureus could potentially contaminate this product due to poor sanitation or bad handling during processing. the aim of this work is: to evalua ...201525944563
plasmid partitioning systems of conjugative plasmids from clostridium perfringens.many pathogenic strains of clostridium perfringens carry several highly similar toxin or antibiotic resistance plasmids that have 35 to 40 kb of very closely related syntenous sequences, including regions that carry the genes encoding conjugative transfer, plasmid replication and plasmid maintenance functions. key questions are how are these closely related plasmids stably maintained in the same cell and what is the basis for plasmid incompatibility in c. perfringens. comparative analysis of the ...201525929175
the role of biological processes in reducing both odor impact and pathogen content during mesophilic anaerobic digestion.mesophilic anaerobic digestion (mad) produces renewable energy, but it also plays a role in reducing the impact of digestates, both by reducing odor and pathogen content. ten full-scale biogas plants characterized by different plant designs (e.g. single digesters, parallel or serial digesters), plant powers (ranging from 180 to 999 kwe), hydraulic retention time (hrt) (ranging between 20 to 70 days) and feed mixes were monitored and odors and pathogens were observed in both ingestates and digest ...201525925189
amino acid residue y196e substitution and c-terminal peptide synergistically alleviate the toxicity of clostridium perfringens epsilon toxin.epsilon toxin (etx) is produced by clostridium perfringens type b and d strains, and is the causative agent of a lethal enterotoxemia in livestock animals and possibly in humans. however, many details of etx structure and activity are not known. therefore, it is important to clarify the relationship between etx structure and activity. to explore the effect and mechanism of etx amino acid residue y196e substitution and c-terminal peptide on toxicity, four recombinant proteins, retx (without 13 n- ...201525912943
in vitro cytotoxicity induced by clostridium perfringens isolate carrying a chromosomal cpe gene is exclusively dependent on sporulation and enterotoxin production.clostridium perfringens type a is a common source of food poisoning (fp) and non-food-borne (nfb) gastrointestinal diseases in humans. in the intestinal tract, the vegetative cells sporulate and produce a major pathogenic factor, c. perfringens enterotoxin (cpe). most type a fp isolates carry a chromosomal cpe gene, whereas nfb type a isolates typically carry a plasmid-encoded cpe. in vitro, the purified cpe protein binds to a receptor and forms pores, exerting a cytotoxic activity in epithelial ...201525912832
use of power ultrasound to enhance the thermal inactivation of clostridium perfringens spores in beef slurry.clostridium perfringens is a pathogen of concern in pasteurised foods. the main objective of this study was to use power ultrasound to enhance the thermal inactivation of c. perfringens spores in beef slurry. the effect of simultaneous ultrasound and heat (ts, thermosonication) on the spore inactivation in beef slurry was first investigated. at 75 °c, a 60 min ts process (24 khz, 0.33 w/g) resulted in a less than 1.5 log reduction for both c. perfringens nzrm 898 and nzrm 2621 spores. then, the ...201525912313
clostridium perfringens alpha-toxin induces gm1a clustering and trka phosphorylation in the host cell membrane.clostridium perfringens alpha-toxin elicits various immune responses such as the release of cytokines, chemokines, and superoxide via the gm1a/trka complex. alpha-toxin possesses phospholipase c (plc) hydrolytic activity that contributes to signal transduction in the pathogenesis of gas gangrene. little is known about the relationship between lipid metabolism and trka activation by alpha-toxin. using live-cell fluorescence microscopy, we monitored transbilayer movement of diacylglycerol (dag) wi ...201525910247
cyclodepsipeptides produced by actinomycetes inhibit cyclic-peptide-mediated quorum sensing in gram-positive bacteria.cyclic peptides are commonly used as quorum-sensing autoinducers in gram-positive firmicutes bacteria. well-studied examples of such molecules are thiolactone and lactone, used to regulate the expression of a series of virulence genes in the agr system of staphylococcus aureus and the fsr system of enterococcus faecalis, respectively. three cyclodepsipeptides ws9326a, ws9326b and cochinmicin ii/iii were identified as a result of screening actinomycetes culture extracts for activity against the a ...201526149266
structural and biochemical analyses of a clostridium perfringens sortase d transpeptidase.the assembly and anchorage of various pathogenic proteins on the surface of gram-positive bacteria is mediated by the sortase family of enzymes. these cysteine transpeptidases catalyze a unique sorting signal motif located at the c-terminus of their target substrate and promote the covalent attachment of these proteins onto an amino nucleophile located on another protein or on the bacterial cell wall. each of the six distinct classes of sortases displays a unique biological role, with sequential ...201526143922
in vitro probiotic characteristics of lactobacillus plantarum zdy 2013 and its modulatory effect on gut microbiota of mice.lactobacillus plantarum zdy 2013, a novel strain isolated from chinese traditional fermented acid beans, was systematically evaluated for its survival capacity under stress conditions (ph, bile salt, simulated gastrointestinal tract, and antibiotics), production of exopolysaccharide and antagonism against 8 pathogens. its effect on mice gut microbiota was also investigated by quantitative pcr and pcr-denaturing gradient gel electrophoresis. the results showed that zdy 2013 can grow at ph 3.5 and ...201526142853
carriage of clostridium perfringens by benthic crabs in a sewage-polluted estuary.the estuary of bahía blanca (ebb), argentina, is an important wetland under intense sewage pollution. we investigated the occurrence of clostridium perfringens (cp) in populations of two benthic crabs (neohelice granulata and cyrtograpsus angulatus) and in sediment from the ebb. cp was found in 49.1% of the crabs and all of the isolates were identified as type a. the alpha (cpa) and enterotoxin (cpe) encoding genes were identified. genetic analyses identified 13 novel sequence types, and found n ...201526130524
differential decay of wastewater bacteria and change of microbial communities in beach sand and seawater microcosms.laboratory microcosm experiments were conducted to determine the decay kinetics of wastewater bacteria and the change of microbial communities in beach sand and seawater. cultivation-based methods showed that common fecal indicator bacteria (fibs; escherichia coli, enterococci, and clostridium perfringens) exhibited biphasic decay patterns in all microcosms. enterococci and c. perfringens, but not e. coli, showed significantly smaller decay rates in beach sand than in seawater. cultivation-indep ...201526125493
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