Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| differential gene expression of pathogens inside infected hosts. | dna microarray is a useful technology for studying differential gene expression in the context of microbe-host interactions. this review concentrates on recent findings of the survival strategies of three intracellular pathogens: shigella flexneri, salmonella enterica serovar typhimurium and mycobacterium tuberculosis. | 2006 | 16459132 |
| new temperate dna phage bcp15 acts as a drug resistance vector. | this study was designed to determine the role of a new temperate dna phage bcp15 in relation to drug resistance. the multidrug resistant shigella flexneri nk1925 was isolated from a patient of infectious diseases hospital, kolkata, india. this strain contained five plasmids ranging in size from 3 to 212 kb. after curing of five plasmids, this strain became sensitive to antibiotics. a plasmidless multidrug-resistant strain burkholderia cepacia dr11 was isolated during the survey of microorganisms ... | 2006 | 16463125 |
| plasmid-mediated bacteriocin production by shigella flexneri isolated from dysenteric diarrhoea and their transformation into escherichia coli. | to determine the production of bacteriocin by shigella flexneri strains, to relate their production to the presence of dysenteric diarrhoea and to asses the genetic determination of the bacteriocin. | 2006 | 16478521 |
| ptdins5p activates the host cell pi3-kinase/akt pathway during shigella flexneri infection. | the virulence factor ipgd, delivered into nonphagocytic cells by the type iii secretion system of the pathogen shigella flexneri, is a phosphoinositide 4-phosphatase generating phosphatidylinositol 5 monophosphate (ptdins5p). we show that ptdins5p is rapidly produced and concentrated at the entry foci of the bacteria, where it colocalises with phosphorylated akt during the first steps of infection. moreover, s. flexneri-induced phosphorylation of host cell akt and its targets specifically requir ... | 2006 | 16482216 |
| comparison of bactericidal activity of six lysozymes at atmospheric pressure and under high hydrostatic pressure. | the antibacterial working range of six lysozymes was tested under ambient and high pressure, on a panel of five gram-positive (enterococcus faecalis, bacillus subtilis, listeria innocua, staphylococcus aureus and micrococcus lysodeikticus) and five gram-negative bacteria (yersinia enterocolitica, shigella flexneri, escherichia coli o157:h7, pseudomonas aeruginosa and salmonella typhimurium). the lysozymes included two that are commercially available (hen egg white lysozyme or hewl, and mutanolys ... | 2006 | 16487612 |
| comparative analysis of tandem t7-like promoter containing regions in enterobacterial genomes reveals a novel group of genetic islands. | based on molecular information theory, 10 t7-like promoter models were built for the t7 group of phages and used to scan their host genomes and closely related genomes. 38 genomes were scanned and 12 clusters of tandem promoters were identified in nine enteropathogens. comparative analysis of these tandem promoter-bearing regions reveals that they are similar to each other, forming prophage-like islands of 4-13 kb. each island appears to contain two or three tandem t7-like promoters within a str ... | 2006 | 16493139 |
| crystal structure of hypothetical protein yfih from shigella flexneri at 2 a resolution. | 2006 | 16498617 | |
| preparation, crystallization and preliminary x-ray crystallographic studies of diadenosine tetraphosphate hydrolase from shigella flexneri 2a. | diadenosine tetraphosphate (ap4a) hydrolase (ec 3.6.1.41) hydrolyzes ap4a symmetrically in prokaryotes. it plays a potential role in organisms by regulating the concentration of ap4a in vivo. to date, no three-dimensional structures of proteins with significant sequence homology to this protein have been determined. the 31.3 kda ap4a hydrolase from shigella flexneri 2a has been cloned, expressed and purified using an escherichia coli expression system. crystals of ap4a hydrolase have been obtain ... | 2005 | 16511239 |
| expression, purification, crystallization and preliminary crystallographic analysis of mxih, a subunit of the shigella flexneri type iii secretion system needle. | a monodisperse truncation mutant of mxih, the subunit of the needle from the shigella flexneri type iii secretion system (ttss), has been overexpressed and purified. crystals were grown of native and selenomethionine-labelled mxih(cdelta5) and diffraction data were collected to 1.9 a resolution. the crystals belong to space group c2, with unit-cell parameters a = 183.4, b = 28.1, c = 27.8 a, beta = 96.5 degrees. an anomalous difference patterson map calculated with the data from the semet-labell ... | 2006 | 16511329 |
| a sitabcd homologue from an avian pathogenic escherichia coli strain mediates transport of iron and manganese and resistance to hydrogen peroxide. | an operon encoding a member of the family of atp-binding cassette (abc) divalent metal ion transporters, homologous to salmonella enterica sitabcd, has been identified in the avian pathogenic escherichia coli (apec) strain chi7122. the sitabcd genes were located on the virulence plasmid papec-1, and were highly similar at the nucleotide level to the chromosomally encoded sitabcd genes present in shigella spp. a cloned copy of sitabcd conferred increased growth upon a siderophore-deficient e. col ... | 2006 | 16514154 |
| is the enthesitis-related arthritis subtype of juvenile idiopathic arthritis a form of chronic reactive arthritis? | enteric organisms are known to trigger reactive arthritis. the enthesitis-related arthritis (era) form of juvenile idiopathic arthritis (jia) clinically resembles reactive arthritis. therefore, we looked for a role of enteric bacteria in era. | 2006 | 16522678 |
| rapid, sequence-specific detection of unpurified pcr amplicons via a reusable, electrochemical sensor. | we report an electrochemical method for the sequence-specific detection of unpurified amplification products of the gyrb gene of salmonella typhimurium. using an asymmetric pcr and the electrochemical e-dna detection scheme, single-stranded amplicons were produced from as few as 90 gene copies and, without subsequent purification, rapidly identified. the detection is specific; the sensor does not respond when challenged with control oligonucleotides based on the gyrb genes of either escherichia ... | 2006 | 16537478 |
| antibacterial activities of medicinal plants used for the treatment of diarrhoea in limpopo province, south africa. | the ethnobotanical survey conducted in this study showed that 21 plant species belonging to 14 families are used in traditional medical practice in limpopo province, south africa, for the treatment of diarrhoea. methanol, ethanol, acetone and hot water extract from different plant parts (leaves, roots, bark and stem rhizome), of several of these plants (indigofera daleoides, punica granatum, syzygium cordatum, gymnosporia senegalensis, ozoroa insignis, elephantorrhiza elephantina, elephantorrhiz ... | 2006 | 16545928 |
| molecular epidemiology of human astrovirus infections in kolkata, india. | the study is aimed to determine the seasonal distribution and clinical characteristics of astroviruses associated with acute watery diarrhoea among children in kolkata and characterize them at the molecular level. | 2006 | 16546454 |
| altering the length of the lipopolysaccharide o antigen has an impact on the interaction of salmonella enterica serovar typhimurium with macrophages and complement. | a panel of isogenic salmonella enterica serovar typhimurium strains that vary only in the length of the o antigen was constructed through complementation of a wzz double mutant (displaying unregulated o-antigen length) with one of two homologous (wzzst and wzzfepe) or three heterologous (wzzo139 of vibrio cholerae and wzzsf and wzzphs-2 of shigella flexneri) wzz genes. each gene was functional in the s. enterica serovar typhimurium host and specified production of o-antigen polymers with lengths ... | 2006 | 16547065 |
| multiple promoters control expression of the yersinia enterocolitica phage-shock-protein a (pspa) operon. | the widely conserved phage-shock-protein a (pspa) operon encodes an extracytoplasmic stress response system that is essential for virulence in yersinia enterocolitica, and has been linked to other important phenotypes in escherichia coli, salmonella enterica and shigella flexneri. regulation of pspa operon expression is mediated through a promoter upstream of pspa that depends on sigma factor rpon (sigma(54)) and the enhancer binding protein pspf. pspa, pspb and pspc, encoded within the pspa ope ... | 2006 | 16549664 |
| shia abrogates the innate t-cell response to shigella flexneri infection. | shigella spp. are the causative agent of bacillary dysentery. infection results in acute colonic injury due to the host inflammatory response. the mediators of the damage, infiltrating polymorphonuclear leukocytes (pmn), also resolve the infection. shigella flexneri's virulence effectors are encoded on its large virulence plasmid and on pathogenicity islands in the chromosome. the shi-2 pathogenicity island encodes the virulence factor shia, which down-regulates shigella-induced inflammation. in ... | 2006 | 16552062 |
| immunocapture uppcr combined with dgge for rapid detection of shigella species. | to develop an immunocapture universal primer pcr (iuppcr) combined with denaturing gradient gel electrophoresis (dgge) and evaluate it as a method permitting rapid detection of shigella species and their serotypes. | 2006 | 16553735 |
| exoproducts of the escherichia coli strain h22 inhibiting some enteric pathogens both in vitro and in vivo. | the antagonistic activity of the escherichia coli strain h22 against enteric bacteria was studied both in vitro and in vivo. | 2006 | 16553738 |
| construction of a multivalent vaccine strain of shigella flexneri and evaluation of serotype-specific immunity. | shigella flexneri causes more fatalities by shigellosis than any other shigella species. there are 13 different serotypes of s. flexneri and their distribution varies between endemic geographical regions. the immune response against s. flexneri is serotype-specific, so current immunization strategies have required the administration of multiple vaccine strains to provide protection against multiple serotypes. in this study, we report the construction of a multivalent s. flexneri vaccine strain, ... | 2006 | 16553820 |
| antibody response to bacterial antigens: characteristics of antibody response to somatic antigens of salmonella typhimurium. | the character of the antibody response in the rabbit to salmonella typhimurium somatic (o) antigen was similar to the response to each of several serotypes of shigella flexneri o antigens, namely a predominance of production of immunoglobulin m (igm) antibody. lipopolysaccharide protein (lpsp) and lipopolysaccharide (lps) fractions of salmonella o antigen differed significantly in both quantitative and qualitative aspects of their immunogenicity. lpsp elicited high levels of agglutinins and also ... | 1970 | 16557720 |
| genetic transfer of shigella flexneri antigens to escherichia coli k-12. | the genes controlling synthesis of shigella flexneri group- and type-specific antigens were transferred to escherichia coli k-12 recipients by conjugation with an s. flexneri hfr. after mating e. coli with an hfr strain of s. flexneri 2a and selecting for his(+) recombinants, a high proportion of the e. coli hybrids agglutinated in s. flexneri grouping serum. none of these hybrids expressed s. flexneri type-specific antigen ii. when an e. coli his(+) hybrid possessing the s. flexneri group antig ... | 1970 | 16557729 |
| infection of cultured mouse macrophages with shigella flexneri. | virulent, avirulent, and attenuated hybrid strains of shigella flexneri 2a are equally susceptible to phagocytosis by cultured mouse peritoneal macrophages. the virulent strain is highly lethal for the macrophages, whereas the avirulent is not and is killed. the attenuated hybrid strain is intermediate in its lethality. comparable results were obtained by using virulent and avirulent s. flexneri 1b, 3, and 5. destruction of macrophages occurs shortly after infection, suggesting virulent strains ... | 1970 | 16557758 |
| inhibition of shigella flexneri by the normal intestinal flora iii. interactions with bacteroides fragilis strains in vitro. | five strains of bacteroides fragilis isolated from human feces were assayed for their inhibitory activities against shigella flexneri in vitro. inhibition was not detected when shigella and the bacteroides strains were simultaneously inoculated into a defined liquid medium containing glucose. inhibition was apparent only when shigella was inoculated into established bacteroides cultures. in exponential-phase cultures, the shigella growth rate was diminished and logarithmic growth was prematurely ... | 1970 | 16557847 |
| a chromosomal locus which controls the ability of shigella flexneri to evoke keratoconjunctivitis. | the primary step in the pathogenesis of bacillary dysentery is the penetration of intestinal epithelial cells by shigellae. lacking this capacity, shigella flexneri becomes avirulent. by means of intergeneric conjugation between various escherichia coli k-12 hfr strains and s. flexneri 2a virulent recipients and by reciprocal transduction analysis with phage p1 vir, we established a locus on the genome of s. flexneri 2a which is necessary for the ability of this strain to penetrate epithelial ce ... | 1971 | 16557949 |
| identification of two widely separated loci conferring nicotinic acid dependence on wild-type shigella flexneri 2a. | two widely separated loci causing the nicotinic acid dependence of wild-type shigella flexneri 2a were identified by intergeneric mating procedures and found to be closely linked to the gal and fuc chromosomal determinants. | 1971 | 16558004 |
| studies in microbic dissociation: ii. changes in the biological characters of shigella paradysenteriae during dissociation and partial reversion. | 1935 | 16559812 | |
| fermentative variability of shigella paradysenteriae, sonne. | 1936 | 16559888 | |
| the increase of bacteriophage in vivo during experimental infections with shigella paradysenteriae, flexner, in mice. | 1945 | 16560915 | |
| two paracolon cultures related antigenically to shigella paradysenteriae. | 1946 | 16561052 | |
| antigenic complex of shigella paradysenteriae, boyd type p274. | 1946 | 16561065 | |
| additional shigella paradysenteriae serotype. | 1946 | 16561096 | |
| epithelial cell penetration as an essential step in the pathogenesis of bacillary dysentery. | labrec, eugene h., herman schneider, thomas j. magnani, and samuel b. formal. epithelial cell penetration as an essential step in the pathogenesis of bacillary dysentery. j. bacteriol. 88:1503-1518. 1964.-a parent strain of shigella flexneri 2a and a colonial mutant derived from it were studied in three animal models. both strains were equally virulent for mice when living cells suspended in hog gastric mucin were injected by the intraperitoneal route. feeding the parent strain to starved guinea ... | 1964 | 16562000 |
| protection of monkeys against experimental shigellosis with attenuated vaccines. | formal, samuel b. (walter reed army institute of research, washington, d.c.), e. h. labrec, amos palmer, and stanley falkow. protection of monkeys against experimental shigellosis with attenuated vaccines. j. bacteriol. 90:63-68. 1965.-two shigella flexneri 2a strains of reduced virulence were used as oral vaccines to protect monkeys against experimental challenge. one strain, a spontaneous mutant, had lost its ability to cause disease and was unable to penetrate the intestinal epithelium and re ... | 1965 | 16562044 |
| genomic divergence of escherichia coli strains: evidence for horizontal transfer and variation in mutation rates. | this report describes the sequencing in the escherichia coli b genome of 36 randomly chosen regions that are present in most or all of the fully sequenced e. coli genomes. the phylogenetic relationships among e. coli strains were examined, and evidence for the horizontal gene transfer and variation in mutation rates was determined. the overall phylogenetic tree indicated that e. coli b and k-12 are the most closely related strains, with e. coli o157:h7 being more distantly related, shigella flex ... | 2005 | 16562379 |
| isolation & antimicrobial susceptibility of shigella from patients with acute gastroenteritis in western nepal. | shigellae play an important role as a causative organism of acute gastroenteritis, which is a global health problem with significant morbidity and mortality in especially in developing countries. this study was carried out to determine the isolation and pattern of antimicrobial resistance of shigella in patients with acute gastroenteritis in western nepal. | 2006 | 16575113 |
| [purification and properties of citrobacter freundii phytase]. | phytase (myo-inositol-1,2,3,4,5,6-hexakisphosphate phosphohydrolase, ec 3.1.3.26) catalyses the stepwise hydrolysis of phytic acid (myo-inositol hexakisphosphate). phytases are of great commercial importance due to their usage as supplement of food and animal feed, which can cater to nutrition demands and alleviate environmental problems, has been approved by many countries. although acid phytases have been extensively studied, information regarding the phytases from citrobacter is limited. in t ... | 2006 | 16579482 |
| rifaximin, a nonabsorbed oral antibiotic, prevents shigellosis after experimental challenge. | this double-blind, placebo-controlled study was conducted to assess the efficacy of the nonabsorbed oral antibiotic rifaximin to prevent shigellosis in volunteers challenged with shigella flexneri. | 2006 | 16586388 |
| the action of photosensitizers and serum in a bactericidal process. ii. the effects of dyes: hypericin, eosin y and saphranine o. | the aim of the present work was to recognize the reasons for differences in the photodynamic action of dyes against various bacterial strains. it is expected that a better understanding of this problem may help in design of new photosensitizers. the sensitivity of 6 various bacterial strains to the photodynamic action of 5 photosensitizers was determined. the hydrophobicity of cell surface and susceptibility of bacteria to the natural defense mechanism of human serum, were estimated. the differe ... | 2005 | 16599305 |
| synthesis and antibacterial activity of substituted flavones, 4-thioflavones and 4-iminoflavones. | synthesis of flavones, 4-thioflavones and 4-iminoflavones was carried out with the substitution of variable halogens, methyl, methoxy and nitro groups in the a, b and ab rings of the respective compounds and we also report here their antibacterial activity. most of the synthesized compounds were found to be active against escherichia coli, bacillus subtilis, shigella flexnari, salmonella aureus, salmonella typhi and pseudomonas aeruginosa. activity of 4-thioflavones and 4-iminoflavones was found ... | 2006 | 16603364 |
| homology modeling and molecular dynamics study of chorismate synthase from shigella flexneri. | shigellosis is a major public health problem in many developing countries. antibiotic therapy can reduce the severity of the dysentery and prevent potentially lethal complication. however, owing to the increased resistance to most of the widely used and inexpensive antibiotics, there is an urgent need for new antibacterial agents, particularly those that act on novel targets. chorismate synthase (cs) is a key enzyme in the shikimic acid pathway, which is essential for the synthesis of aromatic a ... | 2006 | 16616535 |
| synthesis and evaluation of antimicrobial and anticonvulsant activities of some new 3-[2- (5-aryl-1,3,4-oxadiazol-2-yl/4-carbethoxymethylthiazol-2-yl) imino-4-thiazolidinon-5-ylidene]-5-substituted/nonsubstituted 1h-indole-2-ones and investigation of their structure-activity relationships. | in the present study, 20 new compounds having 3-[2-(5-aryl-1,3,4-oxadiazol-2-yl) imino-4-thiazolidinon-5-ylidene]-5-substituted/nonsubstituted 1h-indole-2-one (i-xii) and 3-[2-(4-carbethoxymethylthiazol-2-yl)imino-4-thiazoldinon-5-ylidenel-5-substituted/nonsubstituted ih-indole-2-one (xiii-xx) systems were synthesized. the structures were confirmed by spectral methods (uv, ir, 1h-nmr, 13c-nmr, 13c-dept (135), electron impact mass spectrometry) and elemental analysis. all compounds were tested fo ... | 2006 | 16618017 |
| archaeology and evolution of transfer rna genes in the escherichia coli genome. | transfer rna genes tend to be presented in multiple copies in the genomes of most organisms, from bacteria to eukaryotes. the evolution and genomic structure of trna genes has been a somewhat neglected area of molecular evolution. escherichia coli, the first phylogenetic species for which more than two different strains have been sequenced, provides an invaluable framework to study the evolution of trna genes. in this work, a detailed analysis of the trna structure of the genomes of escherichia ... | 2006 | 16618964 |
| direct visualization of red fluorescent lipoproteins indicates conservation of the membrane sorting rules in the family enterobacteriaceae. | chimeras created by fusing the monomeric red fluorescent protein (rfp) to a bacterial lipoprotein signal peptide (liporfps) were visualized in the cell envelope by epifluorescence microscopy. plasmolysis of the bacteria separated the inner and outer membranes, allowing the specific subcellular localization of liporfps to be determined in situ. when equipped with the canonical inner membrane lipoprotein retention signal cdsr, liporfp was located in the inner membrane in escherichia coli, whereas ... | 2006 | 16672606 |
| future needs and directions for shigella vaccines. | 2006 | 16673461 | |
| antimicrobial activity of 1,2-bis-[2-(5-r)-1h-benzimidazolyl]- 1,2-ethanediols, 1,4-bis-[2-(5-r)-1h-benzimidazolyl]- 1,2,3,4-butanetetraols and their feiii, cuii, and agi complexes. | 1,2-bis-[2-(5-h/me/cl/no2)-1h-benzimidazolyl]-1,2-ethanediols (l1-l4), 1,4-bis-[2-(5-h/me/cl)-1h-benzimidazolyl]-1,2,3,4-butanetetraols (l5-l7) and their complexes with fecl3, cucl2, and agno3 were synthesized; antibacterial activity of the compounds was determined toward staphylococcus aureus, staphylococcus epidermidis, escherichia coli, klebsiella pneumoniae, pseudomonas aeruginosa, salmonella typhi, shigella flexneri, proteus mirabilis, and antifungal activity against candida albicans. the a ... | 2005 | 16681141 |
| antimicrobial activity of znii, cdii, and hgii complexes of 1,2-bis-[2-(5-r)-1h-benzimidazolyl]-1,2-ethanediols and 1,4-bis-[2-(5-r)-1h-benzimidazolyl]-1,2,3,4-butanetetraols. | 1,2-bis-[2-(5-h/me/cl/no2)-1h-benzimidazolyl]-1,2-ethanediols (l1-l4), 1,4-bis-[2-(5-h/me/cl)-1h-benzimidazolyl]-1,2,3,4-butanetetraols (l5-l7) and their complexes with zncl2, cdcl2 and hgcl2 were synthesized and antibacterial activity of the compounds was tested toward staphylococcus aureus, s. epidermidis, escherichia coli, klebsiella pneumoniae, pseudomonas aeruginosa, salmonella typhi, shigella flexneri, proteus mirabilis and antifungal activity against candida albicans. hgii complexes have ... | 2005 | 16681142 |
| the effects of alpha-lactalbumin and glycomacropeptide on the association of caco-2 cells by enteropathogenic escherichia coli, salmonella typhimurium and shigella flexneri. | two milk components, alpha-lactalbumin (alpha-la) and glycomacropeptide (gmp) may inhibit intestinal infection/intoxification. (3)[h] thymidine-labeled enteropathogenic escherichia coli (epec), salmonella typhimurium (atcc 6994) or shigella flexneri (atcc 9199) were introduced to caco-2 cultures and their association with caco-2 cells was assessed. undigested, pepsin-digested and pepsin- and pancreatin-digested alpha-lactalbumin and glycomacropeptide inhibited association. thus, milk supplemente ... | 2006 | 16684117 |
| the emerging strains of shigella dysenteriae type 2 in bangladesh are clonal. | a total of 113 strains of shigella dysenteriae type 2 isolated from patients attending the dhaka diarrhoea treatment centre of icddr,b: centre for health and population research during the period 1999-2004 were studied. serotype of the isolates was confirmed using commercially available antisera. except for arabinose fermentation, all the strains had similar biochemical reactions. more than 60% of the strains were sensitive to commonly used antibiotics; only 6% (n=7) of the strains were resistan ... | 2006 | 16684401 |
| epidemiology and genetic characterization of shigella flexneri strains isolated from three paediatric populations in egypt (2000-2004). | ninety-seven isolates of shigella flexneri from children seeking medical care from three sites in egypt were characterized. overall, 46.4% of children (median age 17 months) were febrile or reported blood in their stools, 25.8% were dehydrated and 16.5% were admitted to hospital. serotypes 2a (37.1%), 1b (18.6%), 1c (17.5%), and 6 (15.5%) comprised over 88.7% of the total isolates. we observed marked resistance to ampicillin (87.6%), tetracycline (84.5%) and trimethoprim-sulfamethoxazole (63.9%) ... | 2006 | 16690004 |
| comparison of the virulence plasmid genomes of two strains of shigella which lost the ability to bind congo red. | we determined and analyzed the shigella flexneri serotype 5 (psf5) and s. dysenteriae serotype 1 (psd1) virulence plasmid genomes. the total length of psf5 is 136513 bp, including 165 open reading frames (orfs). of these orfs, 133 were identified and 32 of those had no significant homology to proteins with known functions. the length of psd1 is 182545 bp, including 224 orfs, of which we identified 181. the remaining 43 orfs were not significantly homologous to proteins with known functions. the ... | 2006 | 16704117 |
| role for erbin in bacterial activation of nod2. | intracellular peptidoglycan (pg) recognition in human cells is mediated by the nacht-lrr proteins nod1 and nod2. elicitation of these proteins by pg motifs released from invasive bacteria triggers signaling events, resulting in the activation of the nf-kappab pathway. in order to decipher the molecular components involved in nod2 signal transduction, we set out to identify new interaction partners of nod2 by using a yeast two-hybrid screen. besides the known interaction partner rip2, the screen ... | 2006 | 16714539 |
| identification of the plasmid-borne quinolone resistance gene qnrs in salmonella enterica serovar infantis. | a salmonella enterica serovar infantis isolate of avian origin was investigated for the presence of the gene qnrs, its transferability and its association with other resistance genes. | 2006 | 16720566 |
| genome-wide detection and analysis of homologous recombination among sequenced strains of escherichia coli. | comparisons of complete bacterial genomes reveal evidence of lateral transfer of dna across otherwise clonally diverging lineages. some lateral transfer events result in acquisition of novel genomic segments and are easily detected through genome comparison. other more subtle lateral transfers involve homologous recombination events that result in substitution of alleles within conserved genomic regions. this type of event is observed infrequently among distantly related organisms. it is reporte ... | 2006 | 16737554 |
| socioeconomic correlates of antibody levels to enteric pathogens among israeli adolescents. | we examined the association between socioeconomic status and the level of serum antibodies to selected faeco-orally transmitted pathogens among israeli adolescents. random samples of eighty volunteers aged 12-15 years from high (hsl), medium (msl) and low (lsl) standard of living towns were included in the study. serum samples were examined by radioimmunoassay for hav and by in-house-developed elisa systems for iga and igg antibody levels against shigella sonnei, s. flexneri, e. coli o157:h7 lip ... | 2007 | 16740193 |
| a novel functional t cell hybridoma recognizes macrophage cell death induced by bacteria: a possible role for innate lymphocytes in bacterial infection. | we have established a novel tcralphabeta (tcrvbeta6)(+)cd4(-)cd8(-) t cell hybridoma designated b6ho3. when the b6ho3 cells were cocultured with bacterial-infected j774 macrophage-like cells, ifn-gamma production by b6ho3 cells was triggered through direct cell-cell contact with dying j774 cells infected with listeria monocytogenes (lm), shigella flexneri, or salmonella typhimurium that expressed the type iii secretion system, but not with intact j774 cells infected with heat-killed lm, nonhemol ... | 2006 | 16751404 |
| enucleated l929 mouse fibroblasts support invasion and multiplication of shigella flexneri 5a. | invasive bacteria can induce their own uptake and specify their intracellular localization; hence it is commonly assumed that proximate modulation of host cell transcription is not required for infection. however, bacteria can also modulate, directly or indirectly, the transcription of many host cell genes, whose role in the infection may be difficult to determine by global gene expression. is the host cell nucleus proximately required for intracellular infection and, if so, for which pathogens ... | 2006 | 16751980 |
| keratitis due to shigella flexneri. | multiresistant shigella flexneri isolates were cultured from the cornea and stool of a girl. genetic analysis showed the isolates were identical. shigella spp. are rare causes of ulcerative keratitis; there have only been 14 published cases since 1943. although prognosis after local treatment is good, shigellosis is a systemic infection, possibly leading to dehydration. | 2006 | 16757643 |
| role of shigella flexneri 2a 34 kda outer membrane protein in induction of protective immune response. | emergence of shigella vaccine is in great need in developing countries. in this paper we have shown that 34 kda shigella flexneri 2a outer membrane protein has a role in eliciting immune responses. when injected parentarally this protein gives significant protection against challenge with virulent shigella flexneri 2a. macrophages activated with the 34 kda protein resulted in the dose dependent production of nitric oxide, the highly reactive free radical responsible for killing of invading bacte ... | 2006 | 16765491 |
| molecular characteristics of class 1 and class 2 integrons and their relationships to antibiotic resistance in clinical isolates of shigella sonnei and shigella flexneri. | to analyse the gene cassettes and determine the roles of class 1 and class 2 integrons in antibiotic-resistant strains of shigella sonnei (n=31) and shigella flexneri (n=33). | 2006 | 16766536 |
| [functional analysis of icsb protein secreted via the type iii secretion system of shigella]. | 2006 | 16780119 | |
| plasticity of the p junc promoter of isec11, a new insertion sequence of the is1111 family. | we describe identification and functional characterization of isec11, a new insertion sequence that is widespread in enteroinvasive e. coli (eiec), in which it is always present on the virulence plasmid (pinv) and very frequently also present on the chromosome. isec11 is flanked by subterminal 13-bp inverted repeats (irs) and is bounded by 3-bp terminal sequences, and it transposes with target specificity without generating duplication of the target site. isec11 is characterized by an atypical t ... | 2006 | 16788177 |
| polar localization of the autotransporter family of large bacterial virulence proteins. | autotransporters are an extensive family of large secreted virulence-associated proteins of gram-negative bacteria. secretion of such large proteins poses unique challenges to bacteria. we demonstrate that autotransporters from a wide variety of rod-shaped pathogens, including icsa and sepa of shigella flexneri, aida-i of diffusely adherent escherichia coli, and brka of bordetella pertussis, are localized to the bacterial pole. the restriction of autotransporters to the pole is dependent on the ... | 2006 | 16788193 |
| a periplasmic glutamate/aspartate binding protein from shigella flexneri: gene cloning, over-expression, purification and preliminary crystallographic studies of the recombinant protein. | periplasmic substrate binding proteins (psbps) are essential components of the bacterial periplasmic transport system, which transports a wide variety of nutrients from the periplasmic space to the cytoplasm. the glutamate/aspartate binding protein sfglu/aspbp is a unique psbp consisting of 279 amino acid residues. the sfglu/aspbp gene was cloned, over-expressed, and purified by immobilized metal ion affinity chromatography and size-exclusion chromatography. the recombinant protein sfglu/aspbp h ... | 2006 | 16800808 |
| post-natal development of the porcine microbiota composition and activities. | the current study describes the development of the porcine microbiota and its metabolic activities during the neonatal and weaning period. using 16s rrna-based approaches, we first analysed the ileal and colonic microbiota of neonatal piglets at days 2, 5 and 12 after birth. to further investigate the effect of weaning at 3 weeks of age, 19-day-old piglets (n = 64) were randomly allocated into two groups. half of the piglets remained with their sows throughout the study, while the remaining pigl ... | 2006 | 16817927 |
| the caenorhabditis elegans abl-1 tyrosine kinase is required for shigella flexneri pathogenesis. | shigellosis is a diarrheal disease caused by the gram-negative bacterium shigella flexneri. following ingestion of the bacterium, s. flexneri interferes with innate immunity, establishes an infection within the human colon, and initiates an inflammatory response that results in destruction of the tissue lining the gut. examination of host cell factors required for s. flexneri pathogenesis in vivo has proven difficult due to limited host susceptibility. here we report the development of a pathoge ... | 2006 | 16820504 |
| molecular cloning and characterization of a large subunit of salmonella typhimurium glutamate synthase (gogat) gene in escherichia coli. | two pathways of ammonium assimilation and glutamate biosynthesis have been identified in microorganisms. one pathway involves the nadp-linked glutamate dehydrogenase, which catalyzes the amination of 2-oxoglutarate to form glutamate. an alternative pathway involves the combined activities of glutamine synthetase, which aminates glutamate to form glutamine, and glutamate synthase, which transfers the amide group of glutamine to 2-oxoglutarate to yield two molecules of glutamate. we have cloned th ... | 2006 | 16820760 |
| complete genome sequence of shigella flexneri 5b and comparison with shigella flexneri 2a. | shigella bacteria cause dysentery, which remains a significant threat to public health. shigella flexneri is the most common species in both developing and developed countries. five shigella genomes have been sequenced, revealing dynamic and diverse features. to investigate the intra-species diversity of s. flexneri genomes further, we have sequenced the complete genome of s. flexneri 5b strain 8401 (abbreviated sf8401) and compared it with s. flexneri 2a (sf301). | 2006 | 16822325 |
| structural mimicry for vinculin activation by ipaa, a virulence factor of shigella flexneri. | invasion of epithelial cells by shigella flexneri is characterized by cytoskeletal rearrangements of the host cell membrane, promoting internalization of the bacterium. the bacterial effector ipaa is injected into the epithelial cell by a type iii secretion apparatus and recruits vinculin to regulate actin polymerization at the site of entry. we analysed the complex formed between a carboxy-terminal fragment of ipaa (ipaa(560-633)) and the vinculin d1 domain (vd1), both in crystals and in soluti ... | 2006 | 16826238 |
| an aflp-based database of shigella flexneri and shigella sonnei isolates and its use for the identification of untypable shigella strains. | amplified fragment length polymorphism (aflp) can be used to assess the genetic diversity of closely related microbial genomes. in this study, the first of its kind for identification of shigella, the high discriminatory power of aflp has been used to determine the genetic relatedness of 230 isolates of shigella flexneri and shigella sonnei strains. an aflp database was generated to demonstrate its utility in the discrimination of closely related strains. based on aflp, s. flexneri strains could ... | 2006 | 16837089 |
| surveillance for bacterial diarrhea and antimicrobial resistance in rural western kenya, 1997-2003. | diarrhea is a major cause of preventable illness in sub-saharan africa. although most cases of bacterial gastroenteritis do not require antimicrobial treatment, antimicrobial use is widespread. we examined the bacterial causes of diarrhea and monitored antimicrobial susceptibilities of isolates through clinic-based surveillance in a rural kenyan community. | 2006 | 16838225 |
| inactivation of gram-negative bacteria in milk and banana juice by hen egg white and lambda lysozyme under high hydrostatic pressure. | the effect of hen egg white lysozyme (hewl) and bacteriophage lambda lysozyme (lal) in combination with high pressure (hp) treatment on the inactivation of four gram-negative bacteria (escherichia coli o157:h7, shigella flexneri, yersinia enterocolitica and salmonella typhimurium), was studied in skim milk (ph 6.8; a(w) 0.997) and in banana juice (ph 3.8; a(w) 0.971). in the absence of lysozymes, s. flexneri was more sensitive to hp in milk than in banana juice, while the opposite was observed f ... | 2006 | 16843561 |
| studies on pongamia pinnata (l.) pierre leaves: understanding the mechanism(s) of action in infectious diarrhea. | while data are available on the effect of medicinal plants on intestinal motility and their antibacterial action, there is a paucity of information on their mode of action on various aspects of diarrheal pathogenicity, namely colonization to intestinal epithelial cells and production/action of enterotoxins. crude decoction of dried leaves of pongamia pinnata was evaluated for its antimicrobial (antibacterial, antigiardial and antirotaviral) effect; and its effect on production and action of ente ... | 2006 | 16845722 |
| enhancement of mice susceptibility to infection with listeria monocytogenes by the treatment of morphine. | the effect of morphine on the susceptibility of balb/c mice to diarrheagenic escherichia coli, shigella flexneri, listeria monocytogenes, salmonella enteritidis, yersinia enterocolitica, was examined via the intraperitoneal inoculation. morphine treatment increased the susceptibility to s. enteritidis and l. monocytogenes, resulting in bacteremia and central nervous system (cns) invasion (for l. monocytogenes), while the infection with other bacteria did not show the systemic dissemination in th ... | 2006 | 16858145 |
| ipad localizes to the tip of the type iii secretion system needle of shigella flexneri. | shigella flexneri, the causative agent of shigellosis, is a gram-negative bacterial pathogen that initiates infection by invading cells within the colonic epithelium. contact with host cell surfaces induces a rapid burst of protein secretion via the shigella type iii secretion system (ttss). the first proteins secreted are ipad, ipab, and ipac, with ipab and ipac being inserted into the host cell membrane to form a pore for translocating late effectors into the target cell cytoplasm. the resulti ... | 2006 | 16861624 |
| role and regulation of the shigella flexneri sit and mnth systems. | shigella flexneri possesses at least two putative high-affinity manganese acquisition systems, sitabcd and mnth. mutations in the genes encoding the components of both of these systems were constructed in s. flexneri. the sita mnth mutant showed reduced growth, relative to the wild type, in luria broth (l broth) containing the divalent metal chelator ethylene diamino-o-dihydroxyphenyl acetic acid, and the addition of either iron or manganese restored growth to the level of the wild-type strain. ... | 2006 | 16861654 |
| spectroscopic and calorimetric analyses of invasion plasmid antigen d (ipad) from shigella flexneri reveal the presence of two structural domains. | shigella flexneri is a facultative intracellular pathogen that causes severe gastroenteritis in humans. invasion plasmid antigen d (ipad) is an essential participant in shigella invasion of intestinal cells, but no detailed structural information is available to help understand the proposed role of ipad in invasion or its interaction with other invasion proteins. therefore, the secondary and tertiary structure and thermal stability of ipad as well as selected ipad deletion mutants were investiga ... | 2006 | 16866368 |
| simple enzymatic in situ generation of dihydroxyacetone phosphate and its use in a cascade reaction for the production of carbohydrates: increased efficiency by phosphate cycling. | a new enzymatic method for the generation of dihydroxyacetone phosphate (dhap) using the acid phosphatase from shigella flexneri (phon-sf) and the cheap phosphate donor pyrophosphate (ppi) is described. the utility of this method was demonstrated in an aldolase-catalyzed condensation carried out in one pot in which dhap was generated and coupled to propionaldehyde to give a yield of 53% of the isolated dephosphorylated end product. | 2006 | 16872211 |
| shigella and autophagy. | bacterial invasion of eukaryotic cells, and host recognition and elimination of the invading bacteria, determines the fate of bacterial infection. once inside mammalian cells, many pathogenic bacteria enter the host cytosol to escape from the lytic compartment and gain a replicative niche. recent studies indicate that autophagy also recognizes intracellular bacteria. although autophagy is a conserved membrane trafficking pathway in eukaryotic cells that sequesters undesirable or recyclable cytop ... | 2006 | 16874102 |
| trend and disease burden of bacillary dysentery in china (1991-2000). | we aimed to determine the burden of bacillary dysentery in china, its cross-regional variations, trends in morbidity and mortality, the causative bacterial species and antimicrobial resistance patterns. | 2006 | 16878230 |
| increasing single and multi-antibiotic resistance in shigella species isolated from shigellosis patients in sana'a, yemen. | the epidemiology and antibiotic susceptibility of shigella species changes over time. updated susceptibility knowledge is necessary for appropriate empirical antibiotic treatment. thus, this research aimed to study these changes in 2 time periods with an interval of 10 years. | 2006 | 16883444 |
| molecular model of a type iii secretion system needle: implications for host-cell sensing. | type iii secretion systems are essential virulence determinants for many gram-negative bacterial pathogens. the type iii secretion system consists of cytoplasmic, transmembrane, and extracellular domains. the extracellular domain is a hollow needle protruding above the bacterial surface and is held within a basal body that traverses both bacterial membranes. effector proteins are translocated, via this external needle, directly into host cells, where they subvert normal cell functions to aid inf ... | 2006 | 16888041 |
| comprehensive proteomic analysis of shigella flexneri 2a membrane proteins. | shigella flexneri is the causative agent of most shigellosis cases in developing countries. we used different proteolytic enzymes to selectively shave the protruding proteins on the surface of purified bacterial membrane sheets or vesicles, and recovered peptides were subsequently identified using 2-d lc-ms/ms. as a result, a total of 666 proteins were unambiguously assigned, including 159 integral membrane proteins, 35 outer membrane proteins and 114 proteins previously annotated as hypothetica ... | 2006 | 16889407 |
| characterization of shigella strains in iran by plasmid profile analysis and pcr amplification of ipa genes. | to characterize shigella clinical strains, we studied 82 shigella strains recovered from 719 stool samples of patients with bloody diarrhea in shiraz, iran, over the period from april to october 2003. serological assay classified the shigella isolates as follows: 61 (74.39%) shigella sonnei isolates, 16 (19.51%) shigella flexneri isolates, 3 (3.65%) shigella boydii isolates, and 2 (2.43%) shigella dysenteriae isolates. in an antibiogram test, all shigella strains were susceptible to ceftazidime, ... | 2006 | 16891506 |
| shigella vulvovaginitis in a prepubertal child. | 2006 | 16912629 | |
| structural organization of the needle complex of the type iii secretion apparatus of shigella flexneri. | the secretion apparatus known as the needle complex (nc) from the bacterium shigella flexneri was studied by single particle electron microscopy. the isolated intact nc appears in projection to be composed of a basal body consisting of seven rings and a protruding needle appendage. a comparison of averaged projections of the intact nc and its fragments revealed the organization of the nc into several major subcomplexes. one of these lacks an inner membrane ring of the basal body but still presen ... | 2007 | 16920362 |
| structural characterization of enterobactin hydrolase iroe. | the proliferation of many pathogenic bacteria is limited by the scarcity of soluble iron in their environment. many of these bacteria scavenge iron by synthesizing and exporting small molecule siderophores that chelate iron. iron-bound siderophores are subsequently imported for metabolic processing. three related serine hydrolases have been characterized biochemically in this pathway: fes, irod, and iroe. here, we report the crystal structure of iroe from uropathogenic escherichia coli cft073. t ... | 2006 | 16922493 |
| fishmeal extract bile salt lactose agar--a differential medium for enteric bacteria. | fishmeal extract bile salt lactose agar (febla), a new differential medium for enteric bacteria was developed and evaluated for its ability to grow and differentiate lactose fermenters (lf) from non-lactose fermenters (nlf) in comparison with macconkeys agar. performance of febla was at par with the latter. on febla medium, the contrast between lf and nlf colonies was pronounced and klebsiella pneumoniae produced more mucoid colonies than on macconkeys agar (hi media). unlike macconkeys agar, a ... | 2006 | 16924840 |
| cholesterol is required to trigger caspase-1 activation and macrophage apoptosis after phagosomal escape of shigella. | pro-inflammatory macrophage apoptosis is pivotal in the aetiology of bacillary dysentery, an acute inflammatory diarrhoea caused by shigella spp. s. flexneri triggers its uptake by macrophages, escapes the phagosome and kills the host cell by a cytotoxic pathway, which activates and requires caspase-1 [interleukin (il)-1beta-converting enzyme] and releases mature il-1beta. the bacterial type iii-secreted translocator/effector protein ipab triggers cell death and directly binds to caspase-1. here ... | 2007 | 16925787 |
| structure of yidb protein from shigella flexneri shows a new fold with homeodomain motif. | 2006 | 16927377 | |
| reciprocal transcriptional and posttranscriptional growth-phase-dependent expression of sfh, a gene that encodes a paralogue of the nucleoid-associated protein h-ns. | the inchi1 self-transmissible plasmid psf-r27 from shigella flexneri 2a strain 2457t harbors sfh, a gene that codes for a protein with strong amino acid sequence homology to the global transcription regulator and nucleoid-associated protein h-ns and to its paralogue, stpa. previously, we discovered that the expression of sfh mrna is growth phase dependent such that in cultures growing in lennox broth at 37 degrees c, the transcript is readily detectable in the early stages of exponential growth ... | 2006 | 16936022 |
| effect of lactoferrin on enteroaggregative e. coli (eaec). | we previously demonstrated that lactoferrin inhibits adherence of enteropathogenic escherichia coli to hep-2 cells and decreases invasiveness of shigella flexneri in hela cells by disruption of the type iii secretory system (ttss) of both enteropathogens. to determine whether these effects were specific to the ttss, we assessed the activity of bovine lactoferrin on enteroaggregative e. coli (eaec), enteropathogens whose virulence is not ttss dependent. bovine lactoferrin at a concentration of 1. ... | 2006 | 16936809 |
| modulation of phosphoinositide metabolism by pathogenic bacteria. | phosphoinositide metabolism plays a pivotal role in the regulation of receptor-mediated signal transduction, actin remodelling and membrane dynamics. phosphoinositides co-ordinate these processes by recruiting protein effectors to distinct cellular membranes in a time- and organelle-dependent manner. intracellular bacterial pathogens interfere with phosphoinositide metabolism to direct their entry into eukaryotic cells, form replication-permissive vacuoles, modulate apoptosis, or trigger fluid s ... | 2006 | 16939534 |
| complete nucleotide sequence of pk245, a 98-kilobase plasmid conferring quinolone resistance and extended-spectrum-beta-lactamase activity in a clinical klebsiella pneumoniae isolate. | a plasmid containing the qnrs quinolone resistance determinant and the gene encoding the shv-2 beta-lactamase has been discovered from a clinical klebsiella pneumoniae strain isolated in taiwan. the complete 98-kb sequence of this plasmid, designated pk245, was determined by using a whole-genome shotgun approach. transfer of pk245 conferred low-level resistance to fluoroquinolones in electroporant escherichia coli epi300. the sequence of the immediate region surrounding qnrs in pk245 is nearly i ... | 2006 | 16940067 |
| mobilizable incq-related plasmid carrying a new quinolone resistance gene, qnrs2, isolated from the bacterial community of a wastewater treatment plant. | plasmid-encoded quinolone resistance was previously reported for different bacteria isolated from patients not only in the united states and asia but also in europe. here we describe the isolation, by applying a new selection strategy, of the quinolone resistance plasmid pgnb2 from an activated sludge bacterial community of a wastewater treatment plant in germany. the hypersensitive escherichia coli strain kam3 carrying a mutation in the multidrug efflux system genes acrab was transformed with t ... | 2006 | 16940104 |
| [ultrastructural changes in shigella flexneri cells during interaction with bacteriocinogenic lactobacillus acidophilus]. | results of electron-microscopic examination of shigella flexneri cells, subjected to influence the bacteriocin-producing lactobacillus acidophilus bacteria are presented. the response of shigellae to bacteriocinogenic lactobacilli was shown both on cellular and population levels. on population level the correlation of various morphological types of shigella cells with increase of involution, lysing and resting forms is revealed. at a cellular level the specific ultrastructural changes of shigell ... | 2006 | 16941871 |
| expression, limited proteolysis and preliminary crystallographic analysis of ipad, a component of the shigella flexneri type iii secretion system. | ipad, the putative needle-tip protein of the shigella flexneri type iii secretion system, has been overexpressed and purified. crystals were grown of the native protein in space group p2(1)2(1)2(1), with unit-cell parameters a = 55.9, b = 100.7, c = 112.0 a, and data were collected to 2.9 a resolution. analysis of the native patterson map revealed a peak at 50% of the origin on the harker section v = 0.5, suggesting twofold non-crystallographic symmetry parallel to the b crystallographic axis. a ... | 2006 | 16946465 |
| characterization of ferric and ferrous iron transport systems in vibrio cholerae. | vibrio cholerae has multiple iron acquisition systems, including tonb-dependent transport of heme and of the catechol siderophore vibriobactin. strains defective in both of these systems grow well in laboratory media and in the infant mouse intestine, indicating the presence of additional iron acquisition systems. previously uncharacterized potential iron transport systems, including a homologue of the ferrous transporter feo and a periplasmic binding protein-dependent atp binding cassette (abc) ... | 2006 | 16952942 |
| visible-light-induced bactericidal activity of a nitrogen-doped titanium photocatalyst against human pathogens. | the antibacterial activity of photocatalytic titanium dioxide (tio(2)) substrates is induced primarily by uv light irradiation. recently, nitrogen- and carbon-doped tio(2) substrates were shown to exhibit photocatalytic activities under visible-light illumination. their antibacterial activity, however, remains to be quantified. in this study, we demonstrated that nitrogen-doped tio(2) substrates have superior visible-light-induced bactericidal activity against escherichia coli compared to pure t ... | 2006 | 16957236 |
| plasmid-mediated quinolone resistance determinant qnrs in enterobacter cloacae. | pcr was used to investigate the occurrence of the plasmid-encoded quinolone resistance determinants qnra and qnrs among diarrhoeagenic enterobacterial isolates recovered from hanoi, vietnam, during the period march 2001 to april 2002. in total, 162 escherichia coli isolates, 28 shigella isolates and three enterobacter cloacae isolates were negative for qnra, while a single ent. cloacae isolate harboured a 50-kb qnrs-positive conjugative plasmid. cloning and sequencing identified a qnrs gene brac ... | 2006 | 16961640 |