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rapid multiple-locus variable-number tandem-repeats analysis of shigella spp. using multicolour capillary electrophoresis.the multiple-locus variable-number tandem-repeats analysis (mlva) method for genotyping has proven to be a fast and reliable typing tool in several bacterial species. mlva is in our laboratory the routine typing method for salmonella enterica subsp. enterica serovar typhimurium, escherichia coli (two assays), listeria monocytogenes and yersinia enterocolitica. the gram-negative invasive enteropathogenic bacterium shigella is the most common cause of bacillary dysentery (shigellosis) worldwide, a ...201020951171
[antibacterial antibodies in human immunoglobulins and sera: past and present].to measure levels of several types of antibacterial antibodies in preparations of normal human immunoglobulin as well as in samples of donor sera obtained in 1965 and 2009.201021061576
surveillance of shigellosis by real-time pcr suggests underestimation of shigellosis prevalence by culture-based methods in a population of rural china.shigellosis is a leading public health issue in china, especially in children under 5 years of age. the disease burden of shigellosis is usually underestimated by conventional culture. in this study, real-time pcr was applied to detect shigella infection in parallel with routine culture, to investigate the true burden of disease caused by shigella spp.201020951728
sensitization of microcin j25-resistant strains by a membrane-permeabilizing peptide.microcin j25 (mccj25) is a plasmid-encoded, 21-amino-acid, antibacterial peptide produced by escherichia coli. mccj25 inhibits rna polymerase and the membrane respiratory chain. mccj25 uptake into e. coli-sensitive strains is mediated by the outer membrane receptor fhua and the inner membrane proteins tonb, exbb, exbd, and sbma. this peptide is active on some e. coli, salmonella, and shigella species strains, while other gram-negative bacteria, such as clinical isolates of enterobacter cloacae, ...201020802073
characterization and antimicrobial activity of 4-(β-d-glucopyranosyl-1→4-α-l-rhamnopyranosyloxy)-benzyl thiocarboxamide; a novel bioactive compound from moringa oleifera seed extract.antimicrobial activity of crude seed extract of moringa oleifera was investigated by thin layer chromatography bioassay against escherichia coli, pseudomonas aeruginosa, staphylococcus aureus, cladosporium cladosporioides, and penicillium sclerotigenum; most of them were prominently inhibited by an isolate with r(f) 0.92-0.96. characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate, methyl n-4-(α-l-r ...201020941575
expression of bacterial virulence factors and cytokines during in vitro macrophage infection by enteroinvasive escherichia coli and shigella flexneri: a comparative study.enteroinvasive escherichia coli (eiec) and shigella spp cause bacillary dysentery in humans by invading and multiplying within epithelial cells of the colonic mucosa. although eiec and shigella share many genetic and biochemical similarities, the illness caused by shigella is more severe. thus, genomic and structure-function molecular studies on the biological interactions of these invasive enterobacteria with eukaryotic cells have focused on shigella rather than eiec. here we comparatively stud ...201020944993
serum neopterin is elevated in patients infected with shigella.abstract:201020727206
integron types, gene cassettes, antimicrobial resistance genes and plasmids of shigella sonnei isolates from outbreaks and sporadic cases in taiwan.this study analysed the presence, location and transferability of integrons and antibiotic resistance genes in 103 shigella sonnei outbreak isolates and in 32 sporadic isolates from taiwan. multiple antimicrobial resistance was common in both outbreak (95 %) and sporadic (97 %) isolates. class 1 integrons were present in 34 outbreak isolates (33 %) and in six sporadic isolates (19 %). this study is the first, to our knowledge, to identify an atypical sul3-associated class 1 integron carrying the ...201020947666
near-atomic resolution analysis of bipd, a component of the type iii secretion system of burkholderia pseudomallei.burkholderia pseudomallei, the causative agent of melioidosis, possesses a type iii protein secretion apparatus that is similar to those found in salmonella and shigella. a major function of these secretion systems is to inject virulence-associated proteins into target cells of the host organism. the bipd gene of b. pseudomallei encodes a secreted virulence factor that is similar in sequence and is most likely to be functionally analogous to ipad from shigella and sipd from salmonella. proteins ...201020823511
medicinal potions used against infectious bowel diseases in mayan traditional medicine.since one of the main health problems of the indigenous population are infectious bowel diseases, we decided to test mayan medicinal potions used to treat these conditions against some of the causal agents.201020728517
an outbreak of shigellosis due to shigella flexneri serotype 3a in a prison in iran.on june 16 and 17, 2007, the medical clinic of a prison in isfahan, iran received multiple reports of gastrointestinal illness among prisoners. a cross-sectional study was therefore undertaken to determine the extent, causative agent and possible source of the outbreak.201020804308
pad4 is essential for antibacterial innate immunity mediated by neutrophil extracellular traps.neutrophils trap and kill bacteria by forming highly decondensed chromatin structures, termed neutrophil extracellular traps (nets). we previously reported that histone hypercitrullination catalyzed by peptidylarginine deiminase 4 (pad4) correlates with chromatin decondensation during net formation. however, the role of pad4 in net-mediated bacterial trapping and killing has not been tested. here, we use pad4 knockout mice to show that pad4 is essential for net-mediated antibacterial function. u ...201020733033
molecular mechanisms of necroptosis: an ordered cellular explosion.for a long time, apoptosis was considered the sole form of programmed cell death during development, homeostasis and disease, whereas necrosis was regarded as an unregulated and uncontrollable process. evidence now reveals that necrosis can also occur in a regulated manner. the initiation of programmed necrosis, 'necroptosis', by death receptors (such as tumour necrosis factor receptor 1) requires the kinase activity of receptor-interacting protein 1 (rip1; also known as ripk1) and rip3 (also kn ...201020823910
prominent human health impacts from several marine microbes: history, ecology, and public health implications.this paper overviews several examples of important public health impacts by marine microbes and directs readers to the extensive literature germane to these maladies. these examples include three types of dinoflagellates (gambierdiscus spp., karenia brevis, and alexandrium fundyense), bmaa-producing cyanobacteria, and infectious microbes. the dinoflagellates are responsible for ciguatera fish poisoning, neurotoxic shellfish poisoning, and paralytic shellfish poisoning, respectively, that have pl ...201020976073
ikkα contributes to canonical nf-κb activation downstream of nod1-mediated peptidoglycan recognition.during pathogen infection, innate immunity is initiated via the recognition of microbial products by pattern recognition receptors and the subsequent activation of transcription factors that upregulate proinflammatory genes. by controlling the expression of cytokines, chemokines, anti-bacterial peptides and adhesion molecules, the transcription factor nuclear factor-kappa b (nf-κb) has a central function in this process. in a typical model of nf-κb activation, the recognition of pathogen associa ...201020976174
domains of the shigella flexneri type iii secretion system ipab protein involved in secretion regulation.type iii secretion systems (t3sss) are key determinants of virulence in many gram-negative bacterial pathogens. upon cell contact, they inject effector proteins directly into eukaryotic cells through a needle protruding from the bacterial surface. host cell sensing occurs through a distal needle "tip complex," but how this occurs is not understood. the tip complex of quiescent needles is composed of ipad, which is topped by ipab. physical contact with host cells initiates secretion and leads to ...201020937761
[susceptibility surveillance of clinical isolates to fluoroquinolone antimicrobial agents from 2003 to 2008: post-marketing study of prulifloxacin].yearly changes in the susceptibility of clinical isolates to ulifloxacin (ufx) and other fluoroquinolones were examined through surveys over 3 periods. in the first survey, 534 strains derived from 19 species were collected from clinical specimens during 6 months from december 2003 to may 2004. in the same way, 805 strains were collected from december 2005 to may 2006 in the second survey, and 863 strains were from december 2007 to may 2008 in the third survey. over these 3 study periods, the su ...201020976880
methods for monitoring trends in the incidence of foodborne diseases: foodborne diseases active surveillance network 1996-2008.foodborne illnesses are a substantial health burden in the united states. the foodborne diseases active surveillance network (foodnet) is the principal foodborne disease component of the centers for disease control and prevention's emerging infections program. foodnet is a collaborative project among centers for disease control and prevention, emerging infections program sites, the u.s. department of agriculture, and the u.s. food and drug administration. one of foodnet's main objectives is to m ...201020617933
safety and immunogenicity of a shigella flexneri 2a invaplex 50 intranasal vaccine in adult volunteers.shigellosis is a leading cause of diarrhea worldwide prompting vaccine development. the shigella flexneri invaplex 50 is a macromolecular complex containing ipab, ipac, and lps, formulated from an aqueous extract of virulent shigella delivered via nasal administration. preclinical vaccine testing demonstrated safety, immunogenicity and efficacy. an open-label dose-escalating phase 1 study evaluated a 3-dose (2-week intervals) regimen via nasal pipette delivery. thirty-two subjects were enrolled ...201020619378
convalescent cultures for control of shigellosis outbreaks.a shigellosis outbreak in the st louis, missouri metropolitan area.201020661101
reduced azithromycin susceptibility in shigella sonnei, united states.to investigate azithromycin susceptibility in shigella sonnei in the united states, we examined the azithromycin minimum inhibitory concentrations (mics) of outbreak and routine human s. sonnei isolates. isolate susceptibility clustered at 8 mg/l, but three isolates displayed higher mics (>64  mg/l) to azithromycin. all three isolates contained a plasmid-encoded mpha gene, known to encode a macrolide-2'-phosphotransferase enzyme. transformation of the mpha gene into escherichia coli dh10b allowe ...201020624094
evidence for alternative quaternary structure in a bacterial type iii secretion system chaperone.type iii secretion systems are a common virulence mechanism in many gram-negative bacterial pathogens. these systems use a nanomachine resembling a molecular needle and syringe to provide an energized conduit for the translocation of effector proteins from the bacterial cytoplasm to the host cell cytoplasm for the benefit of the pathogen. prior to translocation specialized chaperones maintain proper effector protein conformation. the class ii chaperone, invasion plasmid gene (ipg) c, stabilizes ...201020633281
enteropathogenic escherichia coli, samonella, shigella and yersinia: cellular aspects of host-bacteria interactions in enteric diseases.abstract: a successful infection of the human intestine by enteropathogenic bacteria depends on the ability of bacteria to attach and colonize the intestinal epithelium and, in some cases, to invade the host cell, survive intracellularly and disseminate from cell to cell. to accomplish these processes bacteria have evolved an arsenal of molecules that are mostly secreted by dedicated type iii secretion systems, and that interact with the host, subverting normal cellular functions. here we overvi ...201020649986
impact of diet in shaping gut microbiota revealed by a comparative study in children from europe and rural africa.gut microbial composition depends on different dietary habits just as health depends on microbial metabolism, but the association of microbiota with different diets in human populations has not yet been shown. in this work, we compared the fecal microbiota of european children (eu) and that of children from a rural african village of burkina faso (bf), where the diet, high in fiber content, is similar to that of early human settlements at the time of the birth of agriculture. by using high-throu ...201020679230
influences of hydraulic loading rate on svoc removal and microbial community structure in drinking water treatment biofilters.six biofilters were used for advanced treatment of yangtze river source water to investigate the effects of hydraulic loading rate (hlr) on pollutant removal and microbial community. hlr was found to exert significant influences on the removal efficiency of the conventional pollutants and 24 detectable semivolatile organic compounds (svocs). more than 85% of chemical oxygen demand and assimilable organic carbon was removed at the optimal hlr of 3.0 m h(-1). with the increase of hlr, svoc removal ...201020189298
antioxidant, antibacterial and antigiardial activities of walsura robusta roxb.walsura robusta roxb. (family: meliaceae) is a well-known multi-purpose medicinal plant, and has been employed for a wide range of disease conditions without documented scientific data. in the current study, four pure isolated compounds, 3,4,5-trimethoxyphenyl beta-d-glucopyranoside (1), turpinionoside a (2), (+)-lyoniresinol 3alpha-o-beta-d-glucopyranoside (3) and (-)-lyoniresinol 3alpha-o-beta-d-glucopyranoside (4), were isolated from the leaves and twigs of w. robusta. biological evaluation f ...201020461627
cladophora in the great lakes: impacts on beach water quality and human health.cladophora in the great lakes grows rapidly during the warm summer months, detaches, and becomes free-floating mats as a result of environmental conditions, eventually becoming stranded on recreational beaches. cladophora provides protection and nutrients, which allow enteric bacteria such as escherichia coli, enterococci, shigella, campylobacter, and salmonella to persist and potentially regrow in the presence of the algae. as a result of wind and wave action, these microorganisms can detach an ...201020595755
plasmon-induced inactivation of enteric pathogenic microorganisms with ag-agi/al2o3 under visible-light irradiation.the plasmon-induced photocatalytic inactivation of enteric pathogenic microorganisms in water using ag-agi/al(2)o(3) under visible-light irradiation was investigated. the catalyst was found to be highly effective at killing shigella dysenteriae (s. dysenteriae), escherichia coli (e. coli), and human rotavirus type 2 wa (hrv-wa). its bactericidal efficiency was significantly enhanced by hco(3)(-) and so(4)(2-) ions, which are common in water, while phosphate had a slightly positive effect on the ...201020734989
isoprenoid metabolism as a therapeutic target in gram-negative pathogens.gram-negative enterobacteria include a variety of human pathogens, perhaps most notably e. coli, salmonella, shigella, yersinia, and proteus. while there are treatment options for the diseases caused by these organisms, multi-drug resistance is often a problem and development of novel antibiotics has lagged over recent years. in humans, the isoprenoid biosynthetic pathway has become a subject of intense research for therapeutic modulation of human enzymes in diseases including hypercholesterolem ...201020615187
prolonged episodes of acute diarrhea reduce growth and increase risk of persistent diarrhea in children.prolonged episodes of acute diarrhea (prod; duration 7-13 days) or persistent diarrhea (pd; duration ≥14 days) are important causes of undernutrition, yet the epidemiology and nutritional impact of prod are poorly understood.201020638937
antimicrobial resistance and molecular analysis of non-typhoidal salmonella isolates from human in tunisia.during the period from 2006 to 2007, a total of 32 clinical isolates of salmonella enterica were isolated from diarrheagenic stool samples and further examined for their susceptibility to various antibiotics. sixteen of the human isolates were from the capital tunis, 11 were from sousse, four were from nabeul and one was from mahdia, tunisia. the isolates were serotyped and identified at the national centre of enteropathogenic bacteria, pasteur institute, tunis (centre national de salmonella, sh ...201020685046
in silico characterization of shikimate kinase of shigella flexneri: a potential drug target.shigella flexneri is a major pathogen responsible for shigellosis causing massive morbidity among young population and imposes huge socio-economic burden. in this study, shikimate kinase (sk) from s. flexneri was characterized in silico and disordered regions were predicted. motifs and domains were calculated using computational tools. a three dimensional model of shikimate kinase of s.flexneri was constructed using shikimate kinase of e.coli (pdbid: 1kag_a) as template by comparative modeling a ...201020658341
comparison of chromogenic biolog rainbow agar shigella/aeromonas with xylose lysine desoxycholate agar for isolation and detection of shigella spp. from foods.shigella outbreaks are widely reported throughout the world. however, it remains a challenge to isolate shigella spp. from foods by using conventional microbiological media. the main objective of this study was to determine the effectiveness of a novel chromogenic medium, rainbow agar shigella/aeromonas (rainbow agar), for the isolation and detection of shigella spp. in foods. all four shigella species, s. sonnei, s. flexneri, s. dysenteriae, and s. boydii, were studied. rainbow agar was compare ...201020819355
comparison of 61 sequenced escherichia coli genomes.escherichia coli is an important component of the biosphere and is an ideal model for studies of processes involved in bacterial genome evolution. sixty-one publically available e. coli and shigella spp. sequenced genomes are compared, using basic methods to produce phylogenetic and proteomics trees, and to identify the pan- and core genomes of this set of sequenced strains. a hierarchical clustering of variable genes allowed clear separation of the strains into clusters, including known pathoty ...201020623278
[the evolution of the etiological structure of shigellosis]. 201020734730
plasmid-mediated streptomycin and sulfamethoxazole resistance in shigella flexneri 3a.shigellosis is a major cause of diarrhoea-related morbidity and mortality, especially in children in developing countries such as india. recently, it was estimated that 91 million individuals worldwide contract shigellosis each year. the emergence and dissemination of multidrug-resistant strains of shigella is now an emerging global health problem. during the past two decades, much attention was given to re-evaluation of treatment recommendations. in the present study, we investigated a clinical ...201020685089
development of a multiplex real-time pcr assay with internal amplification control for the detection of shigella species and enteroinvasive escherichia coli.shigella species, particularly s. sonnei and s. flexneri, remain some of the leading bacterial etiological agents of gastrointestinal diseases in the united states and globally. the isolation and detection of these foodborne pathogens are critical for preventing the spread of disease and facilitating epidemiological investigations aimed at determining the source of a shigella infection outbreak. a multiplex real-time pcr-based assay was developed that targets all four species of shigella plus en ...201020828467
comparative in vitro activity of tigecycline and other antimicrobial agents against shigella species from kuwait and the united arab of emirates.shigella species isolated from stool samples of symptomatic patients of all age groups at the mubarak al kabir hospital and infectious diseases hospital, kuwait and tawam hospital, uae during a 2-year period were investigated for their susceptibility to tigecycline and several other antibiotics by determining the minimum inhibitory concentrations (mics) using the e test method. a total of 100 and 42 strains were collected from uae and kuwait, respectively. the extent of drug resistance in the sh ...201020701889
the effects of x-ray radiation on escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri inoculated on whole roma tomatoes.in the last two decades several foodborne disease outbreaks associated with produce were reported. tomatoes, in particular, have been associated with several multi-state salmonella outbreaks. inactivation of inoculated escherichia coli o157:h7, listeria monocytogenes, salmonella enterica and shigella flexneri on whole roma tomato surfaces by x-ray at 0.1, 0.5, 0.75, 1.0, and 1.5 kgy was studied. the main purpose of this study was to achieve a 5 log reduction in consistent with the recommendation ...201020832685
transmembrane bax inhibitor motif containing (tmbim) family proteins perturbs a trans-golgi network enzyme, gb3 synthase, and reduces gb3 biosynthesis.globotriaosylceramide (gb3) is a well known receptor for shiga toxin (stx), produced by enterohemorrhagic escherichia coli and shigella dysenteriae. the expression of gb3 also affects several diseases, including cancer metastasis and fabry disease, which prompted us to look for factors involved in its metabolism. in the present study, we isolated two cdnas that conferred resistance to stx-induced cell death in hela cells by expression cloning: ganglioside gm3 synthase and the cooh terminus regio ...201020837469
normal aerobic bacterial conjunctival flora in the crab-eating raccoon (procyon cancrivorus) and coati (nasua nasua) housed in captivity in pernambuco and paraiba (northeast, brazil).to determine the normal aerobic bacterial conjunctival population of the coatis and the crab-eating raccoons housed in captivity in the pernambuco and paraiba states of brazil.201020840103
seasonal variation of enteropathogens in infants and preschoolers with acute diarrhea in western mexico.the present study estimates the prevalence of some enteropathogens in infants and preschoolers with acute diarrhea. from 2006 to 2007, 5459 consecutive stool samples were evaluated. cryptosporidium parvum was the parasite identified with the higher frequency (5.1%), followed by giardia lamblia (1.2%). campylobacter jejuni was isolated in 858 cases (15.7%) and was the most frequent enteropathogen overall. the rates of c parvum, shigella, and salmonella were higher in the summer. rotavirus had the ...201020706147
csra and cra influence shigella flexneri pathogenesis.shigella flexneri is a facultative intracellular pathogen that invades and disrupts the colonic epithelium. in order to thrive in the host, s. flexneri must adapt to environmental conditions in the gut and within the eukaryotic cytosol, including variability in the available carbon sources and other nutrients. we examined the roles of the carbon consumption regulators csra and cra in a cell culture model of s. flexneri virulence. csra is an activator of glycolysis and a repressor of gluconeogene ...201020713625
antibiotic therapy for shigella dysentery.shigella dysentery is a relatively common illness and occasionally causes death, worldwide. mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. the antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.201020687081
assessment of the microbiological safety of dried spices and herbs commercialized in spain.spices and herbs are natural products or their blends that must be free of extraneous matter content. conventional production of these products implicates a number of hygienic problems so spices and herbs may be exposed to a wide range of microbial contamination during pre- and post-harvest and they can present high microbial counts. in this study, we have analyzed the microbial quality of 53 samples of spices and dry herbs collected from spanish markets detecting a contamination of samples of s ...201020848208
hemolysin e (hlye, clya, shea) and related toxins.certain strains of escherichia coli, salmonella enterica and shigella flexneri produce a pore-forming toxin hemolysin e (hlye), also known as cytolysin a (clya) and silent hemolysin, locus a (shea). hlye lyses erythrocytes and mammalian cells, forming transmembrane pores with a minimum internal diameter of-25 a. we review the current knowledge of hlye structure and function in its solution and pore forms, models for membrane insertion, its potential use in biotechnology applications and its rela ...201020687485
shigellosis update: advancing antibiotic resistance, investment empowered vaccine development, and green bananas.shigella is the principal cause of clinical dysentery and an important cause of morbidity and mortality among children in impoverished regions. the purpose of this review is to present key findings in the areas of epidemiology, disease control, and treatment of shigellosis.201020689423
detection of airborne bacteria in a german turkey house by cultivation-based and molecular methods.today's large-scale poultry production with densely stocked and enclosed production buildings is often accompanied by very high concentrations of airborne microorganisms leading to a clear health hazard for employees working in such environments. depending on the expected exposure to microorganisms, work has to be performed under occupational safety conditions. in this study, turkey houses bioaerosols were investigated by cultivation-based and molecular methods in parallel to determine the conce ...201020720091
prevalence of bacteria and parasites in white ibis in egypt.a field survey was conducted to evaluate the prevalence of bacterial infections among free-living white ibis (nipponia nippon) in which 92 bacterial isolates were recovered from 193 different internal organs of 55 apparently healthy ibis. escherichia coli and salmonella spp. were isolated at rates of 43.6% and 14.5%, respectively. the other bacterial pathogens isolated were shigella spp. (34.5%), enterobacter spp. (21.8%) citrobacter spp. (18.1%), klebsiella pneumonia (16.3), staphylococcus aure ...201020857378
microbial community on healthy and diseased leaves of an invasive plant eupatorium adenophorum in southwest china.invasive plants have caused great economic losses and environmental problems worldwide. eupatorium adenophorum is one of the most invasive weeds in china. to better understand its invasive mechanisms, in the present paper, the microbial communities of healthy and diseased leaves of e. adenophorum were obtained using both culture-independent and -dependent methods and their diversities were compared. the bacteria obtained from culture-independent method belong to proteobacteria (95.8%), actinobac ...201020437143
agap2 regulates retrograde transport between early endosomes and the tgn.the retrograde transport route links early endosomes and the tgn. several endogenous and exogenous cargo proteins use this pathway, one of which is the well-explored bacterial shiga toxin. adp-ribosylation factors (arfs) are approximately 20 kda gtp-binding proteins that are required for protein traffic at the level of the golgi complex and early endosomes. in this study, we expressed mutants and protein fragments that bind to arf-gtp to show that arf1, but not arf6 is required for transport of ...201020551179
phenotypic characterization and genomic analysis of the shigella sonnei bacteriophage sp18.a novel bacteriophage that infects shigella sonnei was isolated from the gap river in korea, and its phenotypic and genomic characteristics were investigated. the virus, called sp18, showed morphology characteristic of the family myoviridae, and phylogenetic analysis of major capsid gene (gp23) sequences classified it as a t4-like phage. based on host spectrum analysis, it is lytic to s. sonnei, but not to shigella flexneri, shigella boydii or members of the genera escherichia and salmonella. py ...201020437154
generation of chitin-derived oligosaccharides toxic to pathogenic bacteria using chia74, an endochitinase native to bacillus thuringiensis.to demonstrate that an endochitinase (chia74) native to bacillus thuringiensis can be used to generate chitin-derived oligosaccharides (ogs) with antibacterial activity against a number of aetiological agents of disease, including bacteria that cause diarrhoeal and emetic syndromes in humans.201020557451
a novel anti-virulence gene revealed by proteomic analysis in shigella flexneri 2a.abstract:201020540790
mutagenesis and chemical cross-linking suggest that wzz dimer stability and oligomerization affect lipopolysaccharide o-antigen modal chain length control.in shigella flexneri, the polysaccharide copolymerase (pcp) protein wzz(sf) confers a modal length of 10 to 17 repeat units (rus) to the o-antigen (oag) component of lipopolysaccharide (lps). pcps form oligomeric structures believed to be related to their function. to identify functionally important regions within wzz(sf), random in-frame linker mutagenesis was used to create mutants with 5-amino-acid insertions (termed wzz(i) proteins), and dna sequencing was used to locate the insertions. anal ...201020453100
identification of active site residues in the shigella flexneri glucosyltransferase gtrv.the serotype-specific glucosyltransferase, gtrv, is responsible for glucosylation of the o-antigen repeating unit of shigella flexneri serotype 5a strains. gtrv is an integral inner membrane protein with two essential periplasmic loops: the large loop 2 and the c-terminal loop 10. in this study, the full length of the loop 2 was shown to be necessary for gtrv function. site-directed mutagenesis within this loop revealed that conserved aromatic and charged amino acids have a critical role in the ...201020334579
a soluble form of the pilus protein fima targets the vdac-hexokinase complex at mitochondria to suppress host cell apoptosis.inhibition of apoptotic response of host cells during an early phase of infection is a strategy used by many enteroinvasive bacterial pathogens to enhance their survival. here, we report the identification of a soluble form of the pilus protein fima from the culture supernatants of e. coli k1, salmonella, and shigella that can potently inhibit bax-mediated release of cytochrome c from isolated mitochondria. similar to the infected cells, hct116 cells stably expressing fima display a delay in the ...201020347420
use of optical mapping to sort uropathogenic escherichia coli strains into distinct subgroups.optical maps were generated for 33 uropathogenic escherichia coli (upec) isolates. for individual genomes, the ncoi restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced e. coli and shigella strains. all of the upec isolates clustered separately from the shigella strains as well as the laboratory and enterohaemorrhagic e. coli strains. moreover, the individual strains appeared to ...201020378655
34 kda momp of shigella flexneri promotes tlr2 mediated macrophage activation with the engagement of nf-kappab and p38 map kinase signaling.the 34 kda major outer membrane protein (momp) of shigella flexneri 2a induces combinatorial expression of tlr2 and tlr6 on peritoneal macrophages of balb/c mice. between the two best-characterized tlrs, to date, tlr2 and tlr4, which are chiefly responsible for recognizing majority of bacterial products, tlr2 alone participates in recognition of 34 kda momp. in addition to tlrs, momp enhances the mrna expression of myd88 and traf6 and induces the nuclear translocation of nf-kappab as well as act ...201020347487
long-term downregulation of protease-activated receptor-2 expression in distal colon in rats following bacillary dysentery.the aim of this study was to determine changes of par-2 expression in distal colon and the sensitivity of colonic muscle to sligrl-nh2, the par-2-activating peptide (par-2-ap) following bacillary dysentery. shigella flexneri was administrated intragastrically in healthy male rats to induce bacillary dysentery. the effect of sligrl-nh2 on the motility of colonic muscle strips were examined. the expression of par-2 was determined by immunohistochemistry and western blotting. intragastric administr ...201020347884
isolation and selection of coliphages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing e. coli (ehec and stec) in cattle.to isolate, characterize and select phages as potential biocontrol agents of enterohemorrhagic and shiga toxin-producing escherichia coli (ehec and stec) in cattle.201020353429
molecular architecture of the mn2+-dependent lactonase ulag reveals an rnase-like metallo-beta-lactamase fold and a novel quaternary structure.the ulag gene, located in the ula regulon, is crucial for the catabolism of l-ascorbate under anaerobic conditions and it has been proposed to encode for the putative l-ascorbate-6-p lactonase. the ulag gene is widespread among eubacteria, including human commensal and pathogenic genera such as escherichia, shigella, klebsiella and salmonella. here, we report the three-dimensional structures of the apoenzyme and mn(2+) holoenzyme of ulag from e. coli to 2.6 a resolution, determined using single- ...201020359483
modeling fimbriae mediated parasite-host interactions.type 1 fimbriae are a known virulence factor in a number of pathogenic enterobacteriaceae, including salmonella, shigella and e. coli. yet, they are also expressed by some commensal strains, notably of e. coli. one hypothesis of the role of fimbriae in commensals is that they evoke a small but tolerable host immune response in order to have the host release sialic acid, which is a valuable nutrient. genetic evidence suggests that sialic acid down-regulates fimbriation. this has been believed to ...201020359486
biological potentials and cytotoxicity of various extracts from endemic origanum minutiflorum o. schwarz & p.h. davis.the aim of the present study was to investigate antioxidative, antimicrobial and cytotoxic effects of endemic origanum minutiflorum (o. schwarz & p.h. davis). antioxidant activities of the extracts from o. minutiflorum were evaluated by using dpph radical scavenging, beta-carotene bleaching and metal chelating activity assays. in addition, the amounts of total phenol components in the plant extracts were determined. in the beta-carotene bleaching test, the extracts exhibited in the range of 58.1 ...201020381570
[analysis on bacillary dysentery surveillance data collected from the national surveillance system in 2007.].to improve the national surveillance plan on bacillary dysentery and to increase the sensitivity of the surveillance system on the disease.201020510059
structure of shigella ipgb2 in complex with human rhoa: implications for the mechanism of bacterial guanine nucleotide exchange factor mimicry.a common theme in bacterial pathogenesis is the manipulation of eukaryotic cells by targeting the cytoskeleton. this is in most cases achieved either by modifying actin, or indirectly via activation of key regulators controlling actin dynamics such as rho-gtpases. a novel group of bacterial virulence factors termed the wxxxe family has emerged as guanine nucleotide exchange factors (gefs) for these gtpases. the precise mechanism of nucleotide exchange, however, has remained unclear. here we repo ...201020363740
the effects of a vegetable-derived probiotic lactic acid bacterium on the immune response.the objective of this study was to investigate the probiotic properties of the fermented vegetable derived lactic acid bacterium, l. plantarum. l. plantarum 10hk2 showed antibacterial activity against pathogenic bacteria and immunomodulating effects on murine macrophage cell lines. raw 264.7 cells stimulated with viable cells of this probiotic strain increased the amounts of pro-inflammatory mediators such as il-1beta, il-6 and tnf-alpha, as well as the anti-inflammatory mediator, il-10. icr mic ...201020377751
isolation of bacteriocin-like substances producing bacteria from finished cattle-manure compost and activity evaluation against some food-borne pathogenic and spoilage bacteria.a finished compost sample was examined for bacteriocin-like substance production against five pathogenic bacteria: salmonella typhimurium ef 85-9, escherichia coli o157:h7 atcc 43888, enterococcus faecalis jcm 8726, staphylococcus aureus jcm 2151, and yersinia enterocolitica jcm 7577. at the preliminary detection of bacterial strains exhibiting antimicrobial activity from the compost sample, thirteen strains could be isolated. screening of the inhibitory activity was done using agar-well diffusi ...201020513963
tracking the secretion of fluorescently labeled type iii effectors from single bacteria in real time.a large number of gram negative pathogens use a specialized needle-like molecular machine known as type iii secretion (t3s) system. this highly sophisticated molecular device consists of a basal body spanning the two bacterial membranes and a protruding needle structure that is connected to a distal translocator complex. the main features of the t3s system are (i) activation after host cellular membrane contact and (ii) the ability to "inject" effectors into host cells through the needle apparat ...201020419414
a multiplex pcr method to detect 14 escherichia coli serogroups associated with urinary tract infections.urinary tract infections (utis) are one of the most common bacterial infections and are predominantly caused by uropathogenic escherichia coli (upec). e. coli strains belonging to 14 serogroups, including o1, o2, o4, o6, o7, o8, o15, o16, o18, o21, o22, o25, o75 and o83, are the most frequently detected upec strains in a diverse range of clinical urine specimens. in the current study, the o-antigen gene clusters of e. coli serogroups o1, o2, o18 and o75 were characterized. a multiplex pcr method ...201020434495
three-hour molecular detection of campylobacter, salmonella, yersinia, and shigella species in feces with accuracy as high as that of culture.campylobacter jejuni and salmonella, shigella, and yersinia species (along with shiga toxin-producing escherichia coli) are the most common causes of acute bacterial diarrheal disease in the united states. current detection techniques are time-consuming, limiting usefulness for patient care. we developed and validated a panel of rapid pcr assays for the detection and identification of c. jejuni, c. coli, salmonella, and yersinia species and shigella and enteroinvasive e. coli in stool samples. a ...201020519461
emerging trends in the etiology of enteric pathogens as evidenced from an active surveillance of hospitalized diarrhoeal patients in kolkata, india.abstract:201020525383
modulation of shigella virulence in response to available oxygen in vivo.bacteria coordinate expression of virulence determinants in response to localized microenvironments in their hosts. here we show that shigella flexneri, which causes dysentery, encounters varying oxygen concentrations in the gastrointestinal tract, which govern activity of its type three secretion system (t3ss). the t3ss is essential for cell invasion and virulence. in anaerobic environments (for example, the gastrointestinal tract lumen), shigella is primed for invasion and expresses extended t ...201020436458
antimicrobial resistance patterns and characterization of integrons of shigella sonnei isolates in seoul, 1999-2008.a total of 66 shigella sonnei isolates from 1999 to 2008 in seoul was analyzed for their antimicrobial resistance, carriage of integron, and the patterns of pulsed-field gel electrophoresis (pfge). a high level of antimicrobial resistance to streptomycin (100%), trimethoprim/sulfamethoxazole (95%), tetracycline (94%), nalidixic acid (65%), and ampicillin (41%) was observed among s. sonnei isolates. fourteen profiles of antimicrobial resistance were identified with the most common resistance prof ...201020437157
nmr characterization of the interaction of the salmonella type iii secretion system protein sipd and bile salts.salmonella and shigella bacteria require the type iii secretion system (t3ss) to inject virulence proteins into their hosts and initiate infections. the tip proteins sipd and ipad are critical components of the salmonella and shigella t3ss, respectively. recently, sipd and ipad have been shown to interact with bile salts, which are enriched in the intestines, and are hypothesized to act as environmental sensors for these enteric pathogens. bile salts activate the shigella t3ss but repress the sa ...201020397637
immunochemical studies of shigella flexneri 2a and 6, and shigella dysenteriae type 1 o-specific polysaccharide-core fragments and their protein conjugates as vaccine candidates.there is no licensed vaccine for the prevention of shigellosis. our approach to the development of a shigella vaccines is based on inducing serum igg antibodies to the o-specific polysaccharide (o-sp) domain of their lipopolysaccharides (lps). we have shown that low molecular mass o-sp-core (o-spc) fragments isolated from shigella sonnei lps conjugated to proteins induced significantly higher antibody levels in mice than the full length o-sp conjugates. this finding is now extended to the o-spc ...201020542498
crystallization and preliminary crystallographic studies of corc, a magnesium-ion transporter.corc is a magnesium transporter that is involved in the mg(2+)-efflux function of the cora transporter system, an mg(2+) channel, from shigella flexneri. native corc was purified and crystallized in the native form and in a ligand-free form and diffraction data sets were collected to 2.9 and 3.4 a resolution, respectively. the native corc crystals belonged to space group p2(1)2(1)2(1), with unit-cell parameters a = 64.31, b = 74.44, c = 132.78 a. the ligand-free corc crystals belonged to space g ...201020516599
frequency of viral, bacterial and parasitic enteropathogens among young children with acute diarrhoea in saudi arabia.the frequency of viral, bacterial and parasitic enteropathogens among 270 paediatric patients (< 5 years of age) in various hospitals of makkah and jeddah cities of saudi arabia were investigated.201020527643
prevalence of enterotoxins among escherichia coli isolates causing bacteraemia.the most frequent cause of bacteraemia among gram-negative bacteria is escherichia coli. analysis of the genes encoding the shigella enterotoxin 1 (shet-1), shet-2, enteroaggregative heat stable toxin 1 (east-1) toxins and aggr factor in e. coli strains causing bacteraemia revealed that set1 genes were presented significantly more frequently among quinolone-susceptible strains (p<0.0001), in phylogenetic group b2 (p=0.0004) and in biofilm strains (p=0.02). in contrast, sen genes were significant ...201020529132
carbon metabolism of intracellular bacterial pathogens and possible links to virulence.new technologies such as high-throughput methods and 13c-isotopologue-profiling analysis are beginning to provide us with insight into the in vivo metabolism of microorganisms, especially in the host cell compartments that are colonized by intracellular bacterial pathogens. in this review, we discuss the recent progress made in determining the major carbon sources and metabolic pathways used by model intracellular bacterial pathogens that replicate either in the cytosol or in vacuoles of infecte ...201020453875
acid stress response in enteropathogenic gammaproteobacteria: an aptitude for survival.enteric bacteria such as escherichia coli have acquired a wide array of acid stress response systems to counteract the extreme acidity encountered when invading the host's digestive or urinary tracts. these acid stress response systems are both enzyme and chaperone based. the 3 main enzyme-based acid resistance pathways are glutamate-, arginine-, and lysine-decarboxylase pathways. they are under a complex regulatory network allowing the bacteria to fine tune its response to the external environm ...201020453931
cytoskeleton-modulating effectors of enteropathogenic and enterohemorrhagic escherichia coli: a case for espb as an intrinsically less-ordered effector.enterohemorrhagic and enteropathogenic escherichia coli produce various effector proteins that are directly injected into the host-cell cytosol through the type iii secretion system. e. coli secreted protein (esp)b is one such effector protein, and affects host-cell morphology by reorganizing actin networks. unlike most globular proteins that have well-ordered, rigid structures, the structures of type iii secretion system effectors from pathogenic gram-negative bacteria, including espb, are ofte ...201020477867
the type iii effectors nlee and nleb from enteropathogenic e. coli and ospz from shigella block nuclear translocation of nf-kappab p65.many bacterial pathogens utilize a type iii secretion system to deliver multiple effector proteins into host cells. here we found that the type iii effectors, nlee from enteropathogenic e. coli (epec) and ospz from shigella, blocked translocation of the p65 subunit of the transcription factor, nf-kappab, to the host cell nucleus. nf-kappab inhibition by nlee was associated with decreased il-8 expression in epec-infected intestinal epithelial cells. ectopically expressed nlee also blocked nuclear ...201020485572
progressivemauve: multiple genome alignment with gene gain, loss and rearrangement.multiple genome alignment remains a challenging problem. effects of recombination including rearrangement, segmental duplication, gain, and loss can create a mosaic pattern of homology even among closely related organisms.201020593022
[traveler's diarrhea, the most common health problem of travelers].bacteria cause 50 to 80% of travelers' diarrheic diseases. the most important pathogens include enterotoxigenic escherichia coli (etec), campylobacteria, salmonellae and shigella. diarrheic viruses cause 5 to 25% and protozoa less than 10% of travelers' diarrheas. hand and food hygiene constitute the main preventive measures. treatment of traveler's diarrhea is based on rehydration therapy and rest. antimicrobial therapy is required only in cases with exceptionally severe symptoms.201020486490
violations identified from routine swimming pool inspections--selected states and counties, united states, 2008.swimming is the third most popular u.s. sport or exercise activity, with approximately 314 million visits to recreational water venues, including treated venues (e.g., pools), each year. the most frequently reported type of recreational water illness (rwi) outbreak is gastroenteritis, the incidence of which is increasing. during 1997--2006, chlorine- and bromine-susceptible pathogens (e.g., shigella and norovirus) caused 24 (23%) of 104 treated venue--associated rwi outbreaks of gastroenteritis, ...201020489681
battle and balance at mucosal surfaces--the story of shigella and antimicrobial peptides.shigella is a major cause of morbidity and mortality for children in many developing countries. emergence of antibiotic-resistance among shigella demands the development of effective medicines. antimicrobial peptides (amps) are expressed in phagocytes and at epithelial surfaces and are important effector molecules of innate immunity. we have found that pathogens are able to turn off the endogenous expression of amps, resulting in serious infections such as shigellosis. a therapeutic rationale to ...201020494122
regulation of high-affinity iron acquisition homologues in the tsetse fly symbiont sodalis glossinidius.sodalis glossinidius is a facultative intracellular bacterium that is a secondary symbiont of the tsetse fly (diptera: glossinidae). since studies with other facultative intracellular bacteria have shown that high-affinity iron acquisition genes are upregulated in vivo, we investigated the regulation of several sodalis genes that encode putative iron acquisition systems. these genes, sg1538 (hemt) and sg1516 (sita), are homologous to genes encoding periplasmic heme and iron/manganese transporter ...201020494987
antiviral and anti-inflammatory diterpenoids from the soft coral sinularia gyrosa.chemical investigation of the soft coral sinularia gyrosa led to the purification of three new diterpenoids, designated as gyrosanols a-c (1-3). the structures of 1-3 were elucidated through extensive spectroscopic analyses. compounds 1 and 2 exhibited antiviral activity against hcmv with ic(50)'s of 2.6 and 3.7 microm, respectively. in addition, compounds 1 and 2 showed significant anti-inflammatory activity by reducing the levels of the cox-2 protein (19.6 + or - 3.9% and 29.1 + or - 9.6%, res ...201020499851
microbial contamination of raw meat and its environment in retail shops in karachi, pakistan.this study was conducted to examine the frequency of contamination in retail meat available in karachi, pakistan.201020601790
foodborne illness: is it on the rise?foodborne illness is a serious public health threat. the centers for disease control and prevention (cdc) estimates that 76 million foodborne illnesses, including 325,000 hospitalizations and 5,000 deaths, occur in the united states each year. two recently published foodborne diseases active surveillance network (foodnet) reports showed that salmonella, campylobacter, shigella, cryptosporidium, and shiga toxin escherichia coli (stec) o157 continue to be leading causes of both the number and inci ...201020500787
[antibacterial activity of recombinant thanatin expressed by e.coli er2566].to express antibacterial peptide thanatin in the prokaryotic expression system and test its antibacterial activity.201020501392
protein refolding is required for assembly of the type three secretion needle.pathogenic gram-negative bacteria use a type three secretion system (ttss) to deliver virulence factors into host cells. although the order in which proteins incorporate into the growing ttss is well described, the underlying assembly mechanisms are still unclear. here we show that the ttss needle protomer refolds spontaneously to extend the needle from the distal end. we developed a functional mutant of the needle protomer from shigella flexneri and salmonella typhimurium to study its assembly ...201020543831
production of antimicrobial silver nanoparticles in water extracts of the fungus amylomyces rouxii strain ksu-09.a fungal strain, ksu-09, isolated from the roots of date palm (phoenix dactylifera), was identified as amylomyces rouxii based on sequence analysis of the internal transcribed spacer (its) region of its rrna genes. mycelia-free water extracts obtained from mycelium suspended in water for 72h facilitated the production of stable, predominantly monodispersed and spherical silver nanoparticles (agnps) in the size range of 5-27nm upon addition of 1mm silver nitrate, as determined by the xrd, afm and ...201020619641
synthesis, structure and in vitro antibacterial activities of new hybrid disinfectants quaternary ammonium compounds: pyridinium and quinolinium stilbene benzenesulfonates.the series of pyridinium (1-10) and quinolinium (11-20) stilbene benzenesulfonates have been synthesized and their structures were investigated by uv-vis, ft-ir and (1)h nmr spectroscopy. in addition, compound 5 was also determined by single crystal x-ray diffraction technique. the antibacterial activity of the synthesized compounds against both gram-positive and gram-negative bacteria has been determined. the quinolinium derivatives exhibited two very potent characteristic activities, namely, ( ...201020619939
induction of specific cd8 t cells against intracellular bacteria by cd8 t-cell-oriented immunization approaches.for protection against intracellular bacteria such as mycobacterium tuberculosis and listeria monocytogenes, the cellular arm of adaptive immunity is necessary. a variety of immunization methods have been evaluated and are reported to induce specific cd8(+) t cells against intracellular bacterial infection. modified bcg vaccines have been examined to enhance cd8(+) t-cell responses. naked dna vaccination is a promising strategy to induce cd8(+) t cells. in addition to this strategy, live attenua ...201020508818
["autophagy and microorganisms": hotspots of a mini-symposium]. 201020510155
establishment of specific pathogen-free macaque colonies in tsukuba primate research center of japan for aids research.cynomolgus monkeys have been maintained in indoor facilities as closed colony monkeys in tsukuba primate research center in japan since 1978. several microorganisms, including bacteria, parasites and viruses, were eliminated from the cynomolgus monkeys in this colony of tprc. various kinds of viruses (b virus, measles virus, simian varicella virus, simian immunodeficiency virus, simian t cell leukemia virus, simian d type retrovirus, simian cytomegalovirus, simian epstein-barr virus, and simian ...201020510748
emergence of fluoroquinolone resistance in shigella isolated from andaman & nicobar islands, india. 201020516546
the omptins of yersinia pestis and salmonella enterica cleave the reactive center loop of plasminogen activator inhibitor 1.plasminogen activator inhibitor 1 (pai-1) is a serine protease inhibitor (serpin) and a key molecule that regulates fibrinolysis by inactivating human plasminogen activators. here we show that two important human pathogens, the plague bacterium yersinia pestis and the enteropathogen salmonella enterica serovar typhimurium, inactivate pai-1 by cleaving the r346-m347 bait peptide bond in the reactive center loop. no cleavage of pai-1 was detected with yersinia pseudotuberculosis, an oral/fecal pat ...201020639337
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