Publications

molecular detection of all 34 distinct o-antigen forms of shigella.	shigella is the cause of shigellosis or bacillary dysentery, the occurrence of which is estimated to be 165 million cases per year worldwide, resulting in 1.1 million deaths. rapid and reliable assays for detecting and identifying shigella in food, environmental and clinical samples are therefore necessary. shigella species are traditionally identified by their o antigens. this study developed a dna microarray targeting o-serotype-specific genes to detect all 34 distinct o-antigen forms of shige ...	2009	19074655
increased isolation and characterization of shigella sonnei obtained from hospitalized children in tehran, iran.	shigella flexneri has been the most frequent cause of shigellosis in children in iran. to evaluate the changes in frequency of serogroups, 302 shigella species were isolated in 2003 from hospitalized children, aged less than 12 years, with acute diarrhoea in tehran, iran. the number of collected s. sonnei, s. flexneri, s. boydii, and s. dysenteriae isolates was 178 (58.9%), 110 (37.4%), 10 (3.3%), and 4 (1.3%) respectively. most (94%) s. sonnei isolates were resistant to co-trimoxazole. they wer ...	2008	19069621
prevalence of sulfonamide resistance genes in bacterial isolates from manured agricultural soils and pig slurry in the united kingdom.	the prevalences of three sulfonamide resistance genes, sul1, sul2, and sul3 and sulfachloropyridazine (scp) resistance were determined in bacteria isolated from manured agricultural clay soils and slurry samples in the united kingdom over a 2-year period. slurry from tylosin-fed pigs amended with scp and oxytetracycline was used for manuring. isolates positive for sul genes were further screened for the presence of class 1 and 2 integrons. phenotypic resistance to scp was significantly higher in ...	2009	19064898
tight junctions as targets of infectious agents.	the epithelial barrier is a critical border that segregates luminal material from entering tissues. essential components of this epithelial fence are physical intercellular structures termed tight junctions. these junctions use a variety of transmembrane proteins coupled with cytoplasmic adaptors, and the actin cytoskeleton, to attach adjacent cells together thereby forming intercellular seals. breaching of this barrier has profound effects on human health and disease, as barrier deficiencies ha ...	2009	19059200
characterization of shigella spp. by antimicrobial resistance and pcr detection of ipa genes in an infantile population from porto velho (western amazon region), brazil.	the incidence of shigella spp. was assessed in 877 infants from the public hospital in rondônia (western amazon region, brazil) where shigella represents the fourth cause of diarrhea. twenty-five isolates were identified: 18 were shigella flexneri, three shigella sonnei, three shigella boydii and one shigella dysenteriae. with the exception of s. dysenteriae, all shigella spp. isolated from children with diarrhea acquired multiple antibiotic resistances. pcr detection of ipa virulence genes and ...	2008	19057826
contribution of the periplasmic chaperone skp to efficient presentation of the autotransporter icsa on the surface of shigella flexneri.	icsa is an outer membrane protein in the autotransporter family that is required for shigella flexneri pathogenesis. following its secretion through the sec translocon, icsa is incorporated into the outer membrane in a process that depends on yaet, a component of an outer membrane beta-barrel insertion machinery. we investigated the role of the periplasmic chaperone skp in icsa maturation. skp is required for the presentation of the mature amino terminus (alpha-domain) of icsa on the bacterial s ...	2009	19047350
gef-h1 mediated control of nod1 dependent nf-kappab activation by shigella effectors.	shigella flexneri has evolved the ability to modify host cell function with intracellular active effectors to overcome the intestinal barrier. the detection of these microbial effectors and the initiation of innate immune responses are critical for rapid mucosal defense activation. the guanine nucleotide exchange factor h1 (gef-h1) mediates rhoa activation required for cell invasion by the enteroinvasive pathogen shigella flexneri. surprisingly, gef-h1 is requisite for nf-kappab activation in re ...	2008	19043560
the acrab-tolc pump is involved in multidrug resistance in clinical shigella flexneri isolates.	the two multiple-antibiotic resistance (mar) phenotypes (n = 8, respectively) and susceptible isolates (n = 4) of shigella flexneri from china were characterized involving the efflux pump acrab-tolc. the accumulation of ciprofloxacin, acrab-tolc pcr, and levels of mrna with northern blots were performed in three groups. sequencing of acrab-tolc was performed in selected isolates. an efflux inhibition was performed with phe-arg-beta-naphthylamide. the accumulation of ciprofloxacin at steady state ...	2008	19035770
interaction of enteric bacterial pathogens with murine embryonic stem cells.	embryonic stem (es) cells are susceptible to genetic manipulation and retain the potential to differentiate into diverse cell types, which are factors that make them potentially attractive cells for studying host-pathogen interactions. murine es cells were found to be susceptible to invasion by salmonella enterica serovar typhimurium and shigella flexneri and to the formation of attaching and effacing lesions by enteropathogenic escherichia coli. s. enterica serovar typhimurium and s. flexneri c ...	2009	19029302
antigen-specific b memory cell responses to lipopolysaccharide (lps) and invasion plasmid antigen (ipa) b elicited in volunteers vaccinated with live-attenuated shigella flexneri 2a vaccine candidates.	we evaluated b memory responses in healthy adult volunteers who received one oral dose of live-attenuated shigella flexneri 2a vaccine. lps-specific b(m) cells increased from a median of 0 at baseline to 20 spot forming cells (sfc)/10(6) expanded cells following vaccination (p=0.008). a strong correlation was found between post-vaccination anti-lps b(m) cell counts and peak serum anti-lps igg titers (rs=0.95, p=0.0003). increases in b(m) specific for ipab approaching significance were also obser ...	2009	19022324
spa32 interaction with the inner-membrane spa40 component of the type iii secretion system of shigella flexneri is required for the control of the needle length by a molecular tape measure mechanism.	the effectors of enterocyte invasion by shigella are dependent on a type iii secretion system that contains a needle whose length average does not exceed 50 nm. previously, we reported that spa32 is required for needle length control as well as to switch substrate specificity from mxih to ipa proteins secretion. to identify functional domains of spa32, 11 truncated variants were constructed and analysed for their capacity (i) to control the needle's length; (ii) to secrete the ipa proteins; and ...	2008	19019157
shigella flexneri type iii secretion system effectors ospb and ospf target the nucleus to downregulate the host inflammatory response via interactions with retinoblastoma protein.	ospf, ospg and ipah(9.8) are type iii secretion system (t3ss) effectors of shigella flexneri that downregulate the host innate immune response. ospf modifies mitogen-activated protein kinase pathways and polymorphonuclear leucocyte transepithelial migration associated with shigella invasion. ospf also localizes in the nucleus to mediate chromatin remodelling, resulting in reduced transcription of inflammatory cytokines. we now report that ospb can be added to the set of s. flexneri t3ss effector ...	2009	19017275
mxic is secreted by and controls the substrate specificity of the shigella flexneri type iii secretion apparatus.	many gram-negative pathogenic bacteria use a type iii secretion (t3s) system to interact with cells of their hosts. mechanisms controlling the hierarchical addressing of needle subunits, translocators and effectors to the t3s apparatus (t3sa) are still poorly understood. we investigated the function of mxic, the member of the yopn/inve/sepl family in the shigella flexneri t3s system. inactivation of mxic led specifically to a deregulated secretion of effectors (including ipaa, ipgd, icsb, ipgb2, ...	2009	19017268
tlr4 and myd88 control protection and pulmonary granulocytic recruitment in a murine intranasal rsv immunization and challenge model.	an intranasal vaccine composed of toll-like receptor 2 (tlr2) ligand neisseria meningitidis outer membrane proteins and toll-like receptor 4 (tlr4) ligand shigella flexneri lipopolysaccharide (lps) (protollin) and enriched respiratory syncytial virus (rsv) proteins (ersv) has been demonstrated to promote balanced th1/th2 responses without eosinophil recruitment and to protect against challenge in mouse models. we used tlr2, tlr4 and myeloid differentiation factor 88 (myd88) knock-out (-/-) mice ...	2009	19013492
structure of a shigella effector reveals a new class of ubiquitin ligases.	bacterial pathogens have evolved effector proteins with ubiquitin e3 ligase activities through structural mimicking. here we report the crystal structure of the shigella flexneri type iii effector ipah3, a member of the leucine-rich repeat (lrr)-containing bacterial e3 family. the lrr domain is structurally similar to yersinia pestis yopm and potentially binds to substrates. the structure of the c-terminal e3 domain differs from the typical ring- and hect-type e3s. ipah3 synthesizes a lys48-link ...	2008	18997779
structure of the shigella t3ss effector ipah defines a new class of e3 ubiquitin ligases.	ipah proteins are e3 ubiquitin ligases delivered by the type iii secretion apparatus into host cells upon infection of humans by the gram-negative pathogen shigella flexneri. these proteins comprise a variable leucine-rich repeat-containing n-terminal domain and a conserved c-terminal domain harboring an invariant cysteine residue that is crucial for activity. ipah homologs are encoded by diverse animal and plant pathogens. here we demonstrate that the ipah c-terminal domain carries the catalyti ...	2008	18997778
small-molecule type iii secretion system inhibitors block assembly of the shigella type iii secreton.	type iii secretion systems (t3sss) are essential virulence devices for many gram-negative bacteria that are pathogenic for plants, animals, and humans. they serve to translocate virulence effector proteins directly into eukaryotic host cells. t3sss are composed of a large cytoplasmic bulb and a transmembrane region into which a needle is embedded, protruding above the bacterial surface. the emerging antibiotic resistance of bacterial pathogens urges the development of novel strategies to fight b ...	2009	18996990
analysis of immune responses and serological cross reactivities among vibrio cholerae o1, shigella flexneri 2a and haemophilus influenzae b.	antigenic determinants expressed on the bacterial cell surface are of importance in the serological characterization and microbiological diagnosis. the bacterial strains carrying these identical or similar antigenic epitopes might react with antibodies produced against other strains. in this study, strong immunogenicity and antigenic cross reactivity were demonstrated among v. cholerae o1, s. flexnerii 2a and h. influenzae b surface components. the enzyme linked immunosorbent assay (elisa) resul ...	2008	18954564
detection of protozoan and bacterial pathogens of public health importance in faeces of corvus spp. (large-billed crow).	parasites and bacteria are reported in the faeces of birds in the current study. fresh faecal samples of the large-billed crow (corvus spp.) were collected from the study site at bangsar, an urban setting in kuala lumpur, malaysia. these samples were transported to laboratory and analysed for parasites and bacteria. pre-prepared xld agar plates were used for culturing the bacteria in the laboratory. using the api 20etm test strips, 9 different species of bacteria were identified belonging to the ...	2008	18948884
structural characterization of the type-iii pilot-secretin complex from shigella flexneri.	assembly of the type-iii secretion apparatus, which translocates proteins through both membranes of gram-negative bacterial pathogens into host cells, requires the formation of an integral outer-membrane secretin ring. typically, a small lipidated pilot protein is necessary for the stabilization and localization of this ring. using nmr spectroscopy, we demonstrate that the c-terminal residues 553-570 of the shigella flexneri secretin mxid encompass the minimal binding domain for its cognate pilo ...	2008	18940609
a pilot sheds light on secretin assembly.		2008	18940600
in this issue: proteomics 20/2008.	in this issue of proteomics you will find the following highlighted articles:comprehensively confirmed annotation of short orfsduring the california gold rush, prospectors did not look only for large nuggets to pave their road to riches - they also collected gold dust. the proteomic equivalent of dust is the small orf. it does not pay to put a lower limit on dust or orf size because almost any size may be turned into "cash" or an important peptide. wei et al. demonstrate how a combination of con ...	2008	18924177
experimental type transformation of shigella paradysenteriae (flexner).		1947	18921755
an outbreak of shigella flexneri infection among rheus monkeys.		1948	18915380
[not available].		1948	18911146
responses of human subjects to vaccines in saline-in-mineral oil emulsion; shigella paradysenteriae vaccines.		1948	18897990
prolonged laboratory observations on clinical cases and carriers of shigella flexneri iii following an epidemic.		1948	18864928
invasion by shigella sonnei of tissues of mice following gavage with viable shigella.		1948	18863683
[analysis on incidence of bacillary dysentery in jinan municipality from 1951 to 2005].	to explore the epidemic characteristics of bacterial dysentery in jinan municipality, and to provide scientific basis for effective strategy for bacterial dysentery control.	2008	18844085
prevalence and antibiotic resistant shigellae among primary school children in urban calabar, nigeria.	in a recent study, involving the examination of 593 stool samples obtained from randomly selected children from three primary schools in calabar, shigella spp. were isolated from 123 (20.7%) of the samples. the infection rate was highest among the younger children with (64.2%) 79/123 of the isolates coming from children under 10 years of age. infection rate was comparable among boys and girls (p = 0.1). only two species of shigella were isolated viz: shigella flexneri 12.0% (71/593) and shigella ...	2004	18839866
[htpg protein of shigella flexneri 2a strain 2457t evokes inflammatory response in mice].	to analyze the function of htpg of s. flexneri 2a 2457t, we constructed an htpg deletion mutant and a recovery mutant.	2008	18837368
reduction in infection risk through treatment of microbially contaminated surfaces with a novel, portable, saturated steam vapor disinfection system.	surface-mediated infectious disease transmission is a major concern in various settings, including schools, hospitals, and food-processing facilities. chemical disinfectants are frequently used to reduce contamination, but many pose significant risks to humans, surfaces, and the environment, and all must be properly applied in strict accordance with label instructions to be effective. this study set out to determine the capability of a novel chemical-free, saturated steam vapor disinfection syst ...	2009	18834748
evaluation by real-time pcr of the expression of s. flexneri virulence-associated genes ospb and phon2 under different genetical backgrounds.	under conditions of activated type iii secretion shigella flexneri up-regulates the expression of numerous genes, including the virulence plasmid (pinv)-encoded ospb and phon2 genes. ospb and phon2 are virulence-associated genes which are part of a bicistronic transcriptional unit encoding ospb, a protein (effector) of unknown function secreted by the type iii secretion (tts) apparatus, and phon2 (apyrase or atp-diphosphohydrolase), a periplasmic protein involved in polar icsa localization on th ...	2008	18831939
metal based isatin-derived sulfonamides: their synthesis, characterization, coordination behavior and biological activity.	some isatin derived sulfonamides and their transition metal [co(ii), cu(ii), ni(ii), zn(ii)] complexes have been synthesized and characterized. the structure of synthesized compounds and their nature of bonding have been inferred on the basis of their physical (magnetic susceptibility and conductivity measurements), analytical (elemental analyses) and spectral (ir, (1)h nmr and (13)c nmr) properties. an octahedral geometry has been suggested for co(ii), ni(ii) and zn(ii) and square-planar for cu ...	2009	18825557
nlrc4/ipaf: a card carrying member of the nlr family.	the nod-like receptor (nlr) family of proteins is involved in the regulation of innate immune responses and cell death pathways. recent findings show that the nlr family member nlrc4 (also known as ipaf) has important roles in innate immune responses to gram-negative bacteria. macrophages infected with legionella pneumophila, salmonella typhimurium, shigella flexneri, or pseudomonas aeruginosa activate caspase-1 in an nlrc4-dependent manner leading to macrophage cell death and the release of pro ...	2009	18819842
subproteomic tools to increase genome annotation complexity.	comprehensive and precise annotations of short protein-coding genes are always a challenging task. here we propose a new design to facilitate the characterization of previously overlooked short protein-coding genes by integrating a shotgun proteomics method and oligonucleotide array analysis. using shigella flexneri as a model, we validate 163 annotated orfs and 51 hypothetical or putative transcripts at the protein level, and discover four novel short orfs. this strategy will contribute signifi ...	2008	18814329
incidence of bacterial enteropathogens among hospitalized diarrhea patients from orissa, india.	bacteriological analysis of 1,551 stool/rectal swabs from all age groups of diarrhea patients of different hospitals of orissa from january 2004 to december 2006 was carried out using standard procedures. among all enteropathogens isolated in 886 culture-positive samples, escherichia coli constituted 75.5%, including 13.2% pathogenic e. coli; vibrio cholerae o1 constituted 17.3%; v. cholerae o139, 1%; shigella spp., 4.5% (shigella flexneri type 6, 2.9%, s. dysenteriae type i, 0.7%, s. sonnei, 0. ...	2008	18806340
novel fold of vira, a type iii secretion system effector protein from shigella flexneri.	vira, a secreted effector protein from shigella sp., has been shown to be necessary for its virulence. it was also reported that vira might be related to papain-like cysteine proteases and cleave alpha-tubulin, thus facilitating intracellular spreading. we have now determined the crystal structure of vira at 3.0 a resolution. the shape of the molecule resembles the letter "v," with the residues in the n-terminal third of the 45-kda molecule (some of which are disordered) forming one clearly iden ...	2008	18787201
rapid allelic exchange in enterohemorrhagic escherichia coli (ehec) and other e. coli using lambda red recombination.	this unit describes an allelic exchange system for enterohemorrhagic e. coli (ehec), and similar pathogenic species of bacteria. the phage lambda red recombination system is expressed from a plasmid, inducing a hyper-recombinogenic state where electroporated pcr-generated substrates recombine with the bacterial chromosome at high efficiency. the technique can be used to substitute a drug marker for the gene of interest, or used to generate a clean in-frame deletion of the target gene. single gen ...	2006	18770591
bacterial conjugation in the cytoplasm of mouse cells.	intracellular pathogenic organisms such as salmonellae and shigellae are able to evade the effects of many antibiotics because the drugs are not able to penetrate the plasma membrane. in addition, these bacteria may be able to transfer genes within cells while protected from the action of drugs. the primary mode by which virulence and antibiotic resistance genes are spread is bacterial conjugation. salmonellae have been shown to be competent for conjugation in the vacuoles of cultured mammalian ...	2008	18765719
structural and functional studies indicate that shigella vira is not a protease and does not directly destabilize microtubules.	vira, an essential virulence factor in shigella disease pathogenesis, is involved in the uptake, motility, and cell-to-cell spread of shigella organisms within the human host. these functions have been attributed to a vira protease activity and a mechanism of microtubule destruction via tubulin degradation [yoshida, s., et al. (2006) science 314, 985-989]. we report functional and crystallographic data indicating a novel vira structure that lacks these activities but highlights the homology to t ...	2008	18763811
construction of a trivalent candidate vaccine against shigella species with dna recombination.	in this work asd gene of shigella flexneri 2a strain t32 was replaced by vibrio cholerae toxin b subunit (ctxb) gene with dna recombination in vivo and in vitro. the resulting derivative of t32, designed as fwl01, could stably express ctxb, but its growth in lb medium depended on the presence of diaminopimelic acid (dap). then form i plasmid of shigella sonnei strain s7 was labeled with strain t32 asd gene and mobilized into fwl01. thus a trivalent candidate oral vaccine strain, designed as fsw0 ...	2002	18763059
topology and identification of critical residues of the o-acetyltransferase of serotype-converting bacteriophage, sf6, of shigella flexneri.	the modification of the lps o-antigen, seen in the diverse serotypes of shigella flexneri is brought about by the glucosyltransferases (gtr) and the o-acetyltransferase (oac). in this study, we establish the membrane topology of oac using the dual reporter phoa-laczalpha. we have determined that oac is an integral membrane protein with 10 transmembrane regions. the hydrophilic n- and c-termini are oriented in the cytoplasm. functionally important cytoplasmic and periplasmic loops have also been ...	2008	18755141
occurrence and characteristics of the cytolysin a gene in shigella strains and other members of the family enterobacteriaceae.	cytolysin a (clya, hlye, shea) is a hemolytic pore-forming toxin found in escherichia coli and salmonella enterica serovars typhi and paratyphi a. in the present study, analysis of several shigella strains revealed that they harbor only nonfunctional clya gene copies that have been inactivated either by the integration of insertion sequence (is) elements (shigella dysenteriae, shigella boydii, and shigella sonnei strains) or by a frameshift mutation (shigella flexneri). shigella dysenteriae and ...	2008	18754791
the relationship between genetics and environment in the pathogenesis of rheumatic diseases.	major developments have taken place to further our understanding of the relationship between genetics and the environment in the pathogenesis of rheumatic disorders. the association between hla markers and human disease is becoming clearer. for instance, hla-drw4 frequently occurs in patients with rheumatoid disease, and penicillamine and gold toxicity are seen most often in patients with hla-drw2 or drw3. antisera to b alloantigens help define the genetic differences between systemic lupus eryt ...	1979	18748470
resistance to fluoroquinolones by the combination of target site mutations and enhanced expression of genes for efflux pumps in shigella flexneri and shigella sonnei strains isolated in korea.	among 5938 clinical shigella spp. isolates, two s. flexneri strains were isolated as those resistant to fluoroquinolones based on the mics of the following antibiotics: ciprofloxacin, norfloxacin, ofloxacin, sparfloxacin and levofloxacin. s. flexneri 021787 had three substitutions, one in gyra (ser83leu) and two in parc (ser80ile and arg91gln). s. flexneri 021895 had four substitutions, two in gyra (ser83leu and asp87gly) and two in parc (ser80ile and arg91gln). the increased susceptibility of s ...	2008	18727800
epidemiology of highly endemic multiply antibiotic-resistant shigellosis in children in the peruvian amazon.	our goal was to estimate the impact of a shigella vaccine in an area where shigellosis is endemic by characterizing the disease burden and antibiotic-resistance profiles of isolates and by determining the prevalence of shigella flexneri serotypes.	2008	18710884
bacterial biosensors for rapid and effective monitoring of biodegradation of organic pollutants in wastewater effluents.	significant amounts of toxic substances which are hazardous to animals, plants, microorganisms, and other living organisms including humans are released annually into aquatic and terrestrial environments, mostly from improper wastewater discharges. early detection of such pollutants in wastewater effluents and proper monitoring before their final release into the environment is therefore necessary. in this study, two whole-cell bacterial biosensors were constructed by transforming competent cell ...	2008	18688458
use of mchi encoding immunity to the antimicrobial peptide microcin h47 as a plasmid selection marker in attenuated bacterial live vectors.	live attenuated bacterial strains expressing heterologous antigens represent an attractive vaccine development strategy. however, the use of drug resistance genes for the selection of expression plasmids introduced into live vectors poses theoretical health risks. therefore, we developed a novel approach for plasmid selection based on immunity to the antimicrobial peptide microcin h47 (mcch47). two expression plasmids encoding the reporter green fluorescent protein (gfpuv) were constructed; sele ...	2008	18663003
characterization of soluble complexes of the shigella flexneri type iii secretion system atpase.	the conserved atpase of type iii secretion systems is critical to the export of substrates through the apparatus. we present a characterization of the native t3ss atpase, spa47, from the cytoplasm of shigella flexneri, demonstrating it to be in two distinct high-molecular-weight complexes with spa33: mxin and mxik.	2008	18657109
the c-terminus of ipac is required for effector activities related to shigella invasion of host cells.	invasion plasmid antigen c (ipac) is secreted by the shigella flexneri type iii secretion system (ttss) as an essential trigger of epithelial cell invasion. at the molecular level, ipac possesses a distinct functional organization. the ipac c-terminal region between amino acids 319 and 345 is predicted to form a coiled-coil structure. such alpha-helical motifs appear to be a recurring structural theme among ttss components. together with ipab, this ipac region is also required for the formation ...	2008	18656530
antimicrobial resistance in shigella species isolated in dakar, senegal (2004-2006).	from may 2004 to october 2006, a prospective study was carried out in dakar, senegal, to update information about the antimicrobial susceptibility of shigella spp. isolated from stool specimens. among the 165 non-duplicate strains collected, 81 (49%) were identified as shigella flexneri, 75 (45%) as shigella sonnei, 5 (3%) as shigella boydii, and 4 (2%) as shigella dysenteriae. disk diffusion testing revealed that the majority of isolates were resistant to sulphonamides, trimethoprim-sulfamethox ...	2008	18653976
acute diarrhea due to enteropathogenic bacteria in patients at hospitals in tehran.	during a study examining causes of diarrhea from may 2004 to may 2005, 808 stool specimens were collected from patients with acute diarrhea in tehran. fecal samples were cultured and identified according to the standard biochemical methods. molecular identification of enteropathogens was carried out by amplification of their virulence genes by polymerase chain reaction. a total of 369 (45.6%) bacterial pathogens were recovered from 808 patients as follows: shigella spp., 155 (45.6%); diarrheagen ...	2008	18653967
crystal structure of a glutamate/aspartate binding protein complexed with a glutamate molecule: structural basis of ligand specificity at atomic resolution.	the crystal structure of a periplasmic l-aspartate/l-glutamate binding protein (debp) from shigella flexneri complexed with an l-glutamate molecule has been determined and refined to an atomic resolution of 1.0 a. there are two debp molecules in the asymmetric unit. the refined model contains 4462 non-hydrogen protein atoms, 730 water molecules, 2 bound glutamate molecules, and 2 tris molecules from the buffer used in crystallization. the final r(cryst) and r(free) factors are 13.61% and 16.89%, ...	2008	18640128
structures of synthetic o-antigen fragments from serotype 2a shigella flexneri in complex with a protective monoclonal antibody.	the anti-lps igg mab f22-4, raised against shigella flexneri serotype 2a bacteria, protects against homologous, but not heterologous, challenge in an experimental animal model. we report the crystal structures of complexes formed between fab f22-4 and two synthetic oligosaccharides, a decasaccharide and a pentadecasaccharide that were previously shown to be both immunogenic and antigenic mimics of the s. flexneri serotype 2a o-antigen. f22-4 binds to an epitope contained within two consecutive 2 ...	2008	18621718
lomefloxacin versus trimethoprim/sulfamethoxazole in the treatment of adults with acute bacterial diarrhea.	this study compared the efficacy and safety of lomefloxacin with that of trimethoprim/sulfamethoxazole (tmp/smx) in the treatment of adult patients with acute diarrhea of bacterial etiology. two centers enrolled a total of 133 patients; 99 (74%) presented with severe symptoms. the patients were randomized to receive either lomefloxacin 400 mg once daily (n=68) or tmp/smx 160/800 mg twice daily (n=65) for five days. bacteriologic success was achieved in 89.5% of evaluation lomefloxacin-treated pa ...	1992	18611521
selective activation of human intestinal mast cells by escherichia coli hemolysin.	mast cells (mcs) are recognized to play an important role in bacterial host defense in the murine system. in this study, we studied the interaction of human mcs, isolated from the intestine and purified to homogeneity, with different escherichia coli and shigella flexneri strains. we show that alpha-hemolysin (hly)-producing e. coli strains induce the release of histamine, leukotrienes, and proinflammatory cytokines in intestinal mcs. in contrast, mcs were virtually unresponsive to s. flexneri a ...	2008	18606698
intracellular bacteriolysis triggers a massive apoptotic cell death in shigella-infected epithelial cells.	infected epithelial cells, which act as a first barrier against pathogens, seldom undergo apoptosis. rather, infected epithelial cells undergo a slow cell death that displays hallmarks of necrosis. here, we demonstrate that rapid intracellular lysis of shigella flexneri, provoked by either the use of a diaminopimelic acid auxotroph mutant or treatment of infected cells with antibiotics of the beta-lactam family, resulted in a massive and rapid induction of apoptotic cell death. this intracellula ...	2008	18606244
shigella isolates of nepal: changes in the incidence of shigella subgroups and trends of antimicrobial susceptibility pattern.	shigellosis is an important cause of bloody diarrhoea in all age groups, especially in children. a retrospective study was done to analyse the pattern of shigella isolates and the antimicrobial susceptibility trend of these shigella isolated at different hospitals of nepal from jan, 2003- dec, 2005.	2007	18603983
[electrical resistance of bacterial culture suspension as indicator of epidemic and sporadic variants of shigella].	for the first time method of measurement of electric resistance of bacterial suspension was used for differentiation of "epidemic" and "sporadic" (further used without quotes) variants of shigella species. study of 40 strains of s. flexneri and s. sonnei revealed significant differences in electric resistance of cultures isolated during epidemic outbreaks after the growth during 1 or 6 hours - 18.1+/-8.3 kohm and 84.6+/-7.8 kohm respectively (increase in 4.9-fold; p<0.01), while non significant ...	2008	18597992
[epidemic strains of different plasmidovars of bacteria from shigella genus].	plasmid analysis of 46 strains of shigella species confirmed the view about heterogeneity and variability of plasmids composition in these microorganisms. on the other hand,the presence of low-molecular, multiplicated extrachromosomal replicons, which were stable, was shown. using them, it was possible to divide the shigella isolates into two major plasmidovars, characterize them according to repertoire of the most stable plasmids and determine epidemically significant variants during sporadic a ...	2008	18595459
anti-infectious effect of s-benzylisothiourea compound a22, which inhibits the actin-like protein, mreb, in shigella flexneri.	s-benzylisothiourea compound a22 induces coccoid forms in escherichia coli by inhibiting the function of the actin-like cytoskeletal protein, mreb. the minimum inhibitory concentration of a22 and the minimum concentration to induce coccoid forms for various pathogenic bacteria were determined. at 10 microg/ml, a22 induced coccoid forms in shigella flexneri but did not inhibit the growth. no alteration of coccoid forms in the gram-positive bacteria and anaerobic bacteria tested were observed foll ...	2008	18591769
vibrio cholerae vcib promotes iron uptake via ferrous iron transporters.	vibrio cholerae uses a variety of strategies for obtaining iron in its diverse environments. in this study we report the identification of a novel iron utilization protein in v. cholerae, vcib. the vcib gene and its linked gene, vcia, were isolated in a screen for v. cholerae genes that permitted growth of an escherichia coli siderophore mutant in low-iron medium. the vciab operon encodes a predicted tonb-dependent outer membrane receptor, vcia, and a putative inner membrane protein, vcib. vcib, ...	2008	18586940
design, synthesis, characterization, antibacterial and antifungal activities of a novel class of 5,7-diaryl-4,4-dimethyl-4,5,6,7-tetrahydropyridino[3,4-d]-1,2,3-selenadiazoles.	compound 26 is more potent against escherichia coli. and 24 is more active against staphylococcus aureus, beta-heamolytic streptococcus, vibreo cholerae, salmonella typhii, and shigella flexneri than the standard drug ciprofloxacin. moreover, of all the compounds tested, 26 is more effective against aspergillus flavus and mucor, than the standard drug fluconazole.	2008	18569338
molecular characterization of multidrug-resistant shigella species isolated from epidemic and endemic cases of shigellosis in india.	shigella species represent one of the growing numbers of antimicrobial-resistant bacteria in developing countries. fluoroquinolone-resistant strains of shigella dysenteriae type 1 and shigella flexneri type 2a emerged in india during 2002 and 2003, respectively. sixty strains of shigella from different parts of india were analysed for antimicrobial susceptibility, the presence of the qnr plasmid, mutations in the quinolone resistance determining regions (qrdrs), fluoroquinolone accumulation, and ...	2008	18566144
shigella bacteraemia over a decade in soweto, south africa.	shigella infection rarely penetrates beyond the intestinal mucosa to cause bacteraemia. aids patients may be at increased risk. we investigated shigella bacteraemia rates over a decade in a south african population with a high hiv prevalence and analysed presentation and outcome. a retrospective cohort analysis was performed for hospitalized patients for 2003-2006. the rates were compared to those for 1996-1998. adult medical rates decreased from 0.195/1000 in 1996-1998 to 0.087/1000 admissions ...	2008	18550134
the serine protease motif of pic mediates a dose-dependent mucolytic activity after binding to sugar constituents of the mucin substrate.	the pic gene is harbored on the chromosomes of three important pathogens: enteroaggregative escherichia coli (eaec), uropathogenic e. coli (upec), and shigella flexneri. since pic is secreted into the intestinal lumen during eaec infection, we sought to identify intestinal-mucosal substrates for pic. pic did not damage epithelial cells, cleave fodrin, or degrade host defense proteins embedded in the mucus layer (siga, lactoferrin and lysozyme). however, by using a solid-phase assay to evaluate t ...	2008	18538533
distinct isoforms of phospholipase a2 mediate the ability of salmonella enterica serotype typhimurium and shigella flexneri to induce the transepithelial migration of neutrophils.	salmonella spp. and shigella spp. are responsible for millions of cases of enteric disease each year worldwide. while these pathogens have evolved distinct strategies for interacting with the human intestinal epithelium, they both induce significant proinflammatory responses that result in massive transepithelial migration of neutrophils across the intestinal mucosa. it has previously been shown with salmonella enterica serotype typhimurium that the process of neutrophil transmigration is mediat ...	2008	18505810
the response of type three secretion system needle proteins mxihdelta5, bsaldelta5, and prgidelta5 to temperature and ph.	the type iii secretion system (ttss) is a specialized supramolecular injectisome composed of 25 or more proteins which form basal and extracellular domains and share gross architectural similarities with bacterial flagella. the extracellular component of the "needle complex" is primarily composed of a single monomeric subunit organized in a helical array surrounding a hollow pore and protrudes from the bacterial membrane. it is through this surface appendage that virulence factors are translocat ...	2008	18491382
crystal structure of spa40, the specificity switch for the shigella flexneri type iii secretion system.	the pathogenic bacterium shigella flexneri uses a type iii secretion system to inject virulence factors from the bacterial cytosol directly into host cells. the machinery that identifies secretion substrates and controls the export of extracellular components and effector proteins consists of several inner-membrane and cytoplasmic proteins. one of the inner membrane components, spa40, belongs to a family of proteins proposed to regulate the switching of substrate specificity of the export appara ...	2008	18485071
antimicrobial susceptibility of shigella isolates in eight asian countries, 2001-2004.	shigellosis is a major health problem in developing countries, causing 91 million episodes and 414,000 deaths in asia annually. because of increasing trends towards drug resistance, this study was undertaken to monitor local resistance patterns of shigella isolates from 8 asian countries.	2008	18473096
synthesis, characterization and antimicrobial activity of d metal complexes of some 2-substituted-1h-benzimidazoles.	the metal complexes of nine 2-substituted-1h-benzimidazoles (i-ix) with ni(ii), pd(ii), cu(ii), ag(i), zn(ii) salts were synthesized. the compounds were characterized by melting point, analytical data, ir spectroscopy and magnetic susceptibility. the antimicrobial activity of the compounds was determined by the disk diffusion method in mueller-hinton agar on staphylococcus aureusatcc 6538, staphylococcus epidermidis atcc 12228, escherichia coli atcc 8739, klebsiella pneumoniae atcc 4352, pseudom ...	1999	18472907
safety and immunogenicity of wrsd1, a live attenuated shigella dysenteriae type 1 vaccine candidate.	among shigella serotypes shigella dysenteriae type 1 produces the most severe disease, including cases of hemolytic-uremic syndrome and pandemic outbreaks. wrsd1 is a live s. dysenteriae 1 strain attenuated by deletion of the virg(icsa) gene, which encodes a protein that mediates intercellular spread, and stxa and stxb, which encode the shiga toxin. in this phase i trial five groups of eight subjects ingested escalating doses of wrsd1 ranging from 10(3) to 10(7)cfu. no subject experienced fever ...	2008	18468742
identification of novel genomic islands associated with small rnas.	genome evolution in prokaryotes is assisted by integration of gene pools from phages and plasmids. regions downstream of trnas and tmrnas are considered as hot spots for the integration of these gene pools or genomic islands. till date, genomic islands have been identified only at trna/tmrna genes in the enterobacterial genomes. present work reports 10 distinct small rnas as potent integration sites for genomic islands. a known tool trnacc 1.0 has been used to identify genomic islands associated ...	2007	18467773
simple sequence repeats in different genome sequences of shigella and comparison with high gc and at-rich genomes.	simple sequence repeats (ssrs) are omnipresent in prokaryotes and eukaryotes, and are found anywhere in the genome in both protein encoding and noncoding regions. in present study the whole genome sequences of seven chromosomes (shigella flexneri 2a str301 and 2457t, shigella sonnei, escherichia coli k12, mycobacterium tuberculosis, mycobacterium leprae and staphylococcus saprophyticus) have downloaded from the genbank database for identifying abundance, distribution and composition of ssrs and ...	2008	18464038
immunological evidence for functional rather than structural mimicry by a shigella flexneri y polysaccharide-mimetic peptide.	an approach to vaccine design is the use of molecules that mimic the immunogenic element of interest. in this context, the interaction of mdwnmhaa, a peptide mimic of the shigella flexneri y o polysaccharide (ps), with an anti-carbohydrate monoclonal antibody, as studied previously by x-ray crystallography, suggested the presence of functional rather than structural mimicry and a bound peptide conformation that was not represented significantly in the free-ligand ensemble. the antibody response ...	2008	18463226
an intersubunit active site between supercoiled parallel beta helices in the trimeric tailspike endorhamnosidase of shigella flexneri phage sf6.	sf6 belongs to the podoviridae family of temperate bacteriophages that infect gram-negative bacteria by insertion of their double-stranded dna. they attach to their hosts specifically via their tailspike proteins. the 1.25 a crystal structure of shigella phage sf6 tailspike protein (sf6 tsp) reveals a conserved architecture with a central, right-handed beta helix. in the trimer of sf6 tsp, the parallel beta helices form a left-handed, coiled-beta coil with a pitch of 340 a. the c-terminal domain ...	2008	18462681
mutagenesis of the shigella flexneri autotransporter icsa reveals novel functional regions involved in icsa biogenesis and recruitment of host neural wiscott-aldrich syndrome protein.	the icsa (virg) protein of shigella flexneri is a polarly localized, outer membrane protein that is essential for virulence. within host cells, icsa activates the host actin regulatory protein, neural wiskott-aldrich syndrome protein (n-wasp), which in turn recruits the arp2/3 complex, which nucleates host actin to form f-actin comet tails and initiate bacterial motility. linker insertion mutagenesis was undertaken to randomly introduce 5-amino-acid in-frame insertions within icsa. forty-seven l ...	2008	18456802
deoxycholate interacts with ipad of shigella flexneri in inducing the recruitment of ipab to the type iii secretion apparatus needle tip.	type iii secretion (tts) is an essential virulence function for shigella flexneri that delivers effector proteins that are responsible for bacterial invasion of intestinal epithelial cells. the shigella tts apparatus (ttsa) consists of a basal body that spans the bacterial inner and outer membranes and a needle exposed at the pathogen surface. at the distal end of the needle is a "tip complex" composed of invasion plasmid antigen d (ipad). ipad not only regulates tts, but is required for the rec ...	2008	18450744
shigellosis: the current status of vaccine development.	shigellosis, a major form of bacillary dysentery, is caused by infection with shigella organisms. in poor countries, shigella-caused dysentery is endemic and causes an estimated 163 million illness episodes annually and more than one million deaths. although several strategies have been used to develop vaccines targeting shigellosis, none has been licensed for use outside china. owing to the wide range of shigella serotypes and subtypes, there is a need for a multivalent vaccine representing pre ...	2008	18448978
alternative hand contamination technique to compare the activities of antimicrobial and nonantimicrobial soaps under different test conditions.	antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. however, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. the aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimi ...	2008	18441107
virulent shigella flexneri subverts the host innate immune response through manipulation of antimicrobial peptide gene expression.	antimicrobial factors are efficient defense components of the innate immunity, playing a crucial role in the intestinal homeostasis and protection against pathogens. in this study, we report that upon infection of polarized human intestinal cells in vitro, virulent shigella flexneri suppress transcription of several genes encoding antimicrobial cationic peptides, particularly the human beta-defensin hbd-3, which we show to be especially active against s. flexneri. this is an example of targeted ...	2008	18426984
comparing the antimicrobial effectiveness of nacl and kcl with a view to salt/sodium replacement.	a study using a small range of pathogenic bacterial species (aeromonas hydrophila, enterobacter sakazakii, shigella flexneri, yersinia enterocolitica and 3 strains of staphylococcus aureus) has shown that potassium chloride has an equivalent antimicrobial effect on these organisms when calculated on a molar basis. combined nacl and kcl experiments were carried out and data was analysed using a modification to the lambert and lambert [lambert, r.j.w., and lambert, r., 2003. a model for the effica ...	2008	18423764
role of rna polymerase sigma-factor (rpos) in induction of glutamate-dependent acid-resistance of escherichia albertii under anaerobic conditions.	escherichia albertii is a potential enteric food-borne pathogen with poorly defined genetic and biochemical properties. acid resistance is perceived to be an important property of enteric pathogens, enabling them to survive passage through stomach acidity so that they may colonize the mammalian gastrointestinal tract. we analyzed glutamate-dependent acid-resistance pathway (gdar) in five e. albertii strains that have been identified so far. we observed that the strains were unable to induce gdar ...	2008	18422618
structure and genetics of shigella o antigens.	this review covers the o antigens of the 46 serotypes of shigella, but those of most shigella flexneri are variants of one basic structure, leaving 34 shigella distinct o antigens to review, together with their gene clusters. several of the structures and gene clusters are reported for the first time and this is the first such group for which structures and dna sequences have been determined for all o antigens. shigella strains are in effect escherichia coli with a specific mode of pathogenicity ...	2008	18422615
containment of tumor-colonizing bacteria by host neutrophils.	administration of facultative anaerobic bacteria like salmonella typhimurium, shigella flexneri, and escherichia coli to tumor-bearing mice leads to a preferential accumulation and proliferation of the microorganisms within the solid tumor. until now, all known tumor-targeting bacteria have shown poor dissemination inside the tumors. they accumulate almost exclusively in large necrotic areas and spare a rim of viable tumor cells. interestingly, the bacteria-containing necrotic region is separate ...	2008	18413765
analysis of bacterial dna in synovial tissue of tunisian patients with reactive and undifferentiated arthritis by broad-range pcr, cloning and sequencing.	bacteria and/or their antigens have been implicated in the pathogenesis of reactive arthritis (rea). several studies have reported the presence of bacterial antigens and nucleic acids of bacteria other than those specified by diagnostic criteria for rea in joint specimens from patients with rea and various arthritides. the present study was conducted to detect any bacterial dna and identify bacterial species that are present in the synovial tissue of tunisian patients with reactive arthritis and ...	2008	18412942
a pharmacokinetic study of enrofloxacin and its active metabolite ciprofloxacin after oral and intramuscular dosing of enrofloxacin in rhesus monkeys (macaca mulatta).	enrofloxacin is used for treating shigellosis in non-human primates; however, there are no reports describing its pharmacokinetics in rhesus monkeys. pharmacokinetic data in intended target species (rhesus) help to determine the proper dose regimen. blood levels of enrofloxacin and ciprofloxacin (enrofloxacin's active metabolite), were determined after either intramuscular or oral dosing of enrofloxacin for 7 days in a cross-over study. levels of both antibiotics were determined by solid phase e ...	2008	18384536
ospf directly attenuates the activity of extracellular signal-regulated kinase during invasion by shigella flexneri in human dendritic cells.	shigella spp., gram-negative pathogenic bacteria, deliver various effector molecules into the host cell cytoplasm through their type iii secretion system to facilitate their invasive process and control the host innate immune responses. although the function of these effectors is well characterized in epithelial cells during shigella infection, it has not been elucidated in the dendritic cell (dc), a major antigen presenting cell playing an important role in the initiation of immune responses. i ...	2008	18378312
coiled-coil regions play a role in the function of the shigella flexneri o-antigen chain length regulator wzzphs2.	regulation of the length of the o-antigen (oag) chain attached to lps in shigella flexneri is important for virulence and is dependent on the inner-membrane protein wzz. a lack of high-resolution structural data for wzz has hampered efforts so far to correlate mutations affecting function of wzz with structure and describe a mechanism for chain length regulation. here we have used secondary structure prediction to show that the periplasmic domain of the wzz(phs2) protein has three regions of sig ...	2008	18375803
analysis of rho-gtpase mimicry by a family of bacterial type iii effector proteins.	microbial pathogens may hijack the actin cytoskeleton machinery to facilitate actin-based motility, cellular invasion, and intracellular trafficking through the endocytic pathway. of particular interest has been a large class of virulence factors collectively termed the type iii "effector" proteins. following contact with a eukaryotic cell, gram-negative bacterial pathogens employ a dedicated protein secretion apparatus termed type iii to translocate effector proteins into the cellular cytoplasm ...	2008	18374161
differential regulation by magnesium of the two msbb paralogs of shigella flexneri.	shigella flexneri, a gram-negative enteric pathogen, is unusual in that it contains two nonredundant paralogous genes that encode the myristoyl transferase msbb (lpxm) that catalyzes the final step in the synthesis of the lipid a moiety of lipopolysaccharide. msbb1 is encoded on the chromosome, and msbb2 is encoded on the large virulence plasmid present in all pathogenic shigellae. we demonstrate that myristoyl transferase activity due to msbb2 is detected in limited magnesium medium, but not in ...	2008	18359815
differential expression of ompc and ompf in multidrug-resistant shigella dysenteriae and shigella flexneri by aqueous extract of aegle marmelos, altering its susceptibility toward beta-lactam antibiotics.	steadily increasing resistance among shigella to beta-lactams, aminoglycosides, and tetracycline has compromised the utility of these commonly used antimicrobial agents. also, undesirable side effects of certain antibiotics have triggered immense interest in search of alternative therapies using medicinal plants. one such medicinal plant used since ancient times to cure diarrhea is aegle marmelos. the present study exemplifies the susceptibility of beta-lactam-resistant shigella dysenteriae and ...	2008	18358664
maturation of paneth cells induces the refractory state of newborn mice to shigella infection.	the intestinal tract of adult mice is naturally resistant to infection by shigella, the causative agent of bacillary dysentery in humans. conversely, newborn mice are highly susceptible to intragastric shigella infection and develop inflammatory lesions of the jejunal mucosa, very similar to those observed in the colon of dysenteric patients. however, the susceptibility period is short and one week after birth, animals have acquired a status of resistance characteristic of adult animals. to iden ...	2008	18354217
cold shock exoribonuclease r (vacb) is involved in aeromonas hydrophila pathogenesis.	in this study, we cloned and sequenced a virulence-associated gene (vacb) from a clinical isolate ssu of aeromonas hydrophila. we identified this gene based on our recently annotated genome sequence of the environmental isolate atcc 7966(t) of a. hydrophila and the vacb gene of shigella flexneri. the a. hydrophila vacb protein contained 798 amino acid residues, had a molecular mass of 90.5 kda, and exhibited an exoribonuclease (rnase r) activity. the rnase r of a. hydrophila was a cold-shock pro ...	2008	18344363
impact of infections and normal flora in nonhuman primates on drug development.	preclinical safety studies that are required for the marketing approval of a pharmaceutical include single and repeat dose studies in rodent and nonrodent species. the use of nonhuman primates (nhps), primarily macaques, as the nonrodent species has increased in recent years, in part due to the increase in development of biopharmaceuticals and immunomodulatory agents. depending on the source of the macaques, they may vary in genetic background, normal flora, and/or the incidence of preexisting p ...	2008	18323580
delivery of biologically active anti-inflammatory cytokines il-10 and il-1ra in vivo by the shigella type iii secretion apparatus.	pathogenicity of many gram-negative bacteria relies on a type iii secretion (t3s) apparatus, which is used for delivery of bacterial effectors into the host cell cytoplasm allowing the bacteria to manipulate host cell cytoskeleton network as well as to interfere with intracellular signaling pathways. in this study, we investigated the potential of the shigella flexneri t3sa as an in vivo delivery system for biologically active molecules such as cytokines. the anti-inflammatory cytokines il-10 an ...	2008	18322242
ipgb1 and ipgb2, two homologous effectors secreted via the mxi-spa type iii secretion apparatus, cooperate to mediate polarized cell invasion and inflammatory potential of shigella flexenri.	type iii secretion systems (t3ss) are present in many pathogenic gram-negative bacteria and mediate the translocation of bacterial effector proteins into host cells. here, we report the phenotypic characterization of s. flexneri ipgb1 and ipgb2 mutants, in which the genes encoding the ipgb1 and ipgb2 effectors have been inactivated, either independently or simultaneously. like ipgb1, we found that ipgb2 is secreted by the t3ss and its secretion requires the spa15 chaperone. upon infection of sem ...	2008	18316224
structures of the shigella flexneri type 3 secretion system protein mxic reveal conformational variability amongst homologues.	many gram-negative pathogenic bacteria use a complex macromolecular machine, known as the type 3 secretion system (t3ss), to transfer virulence proteins into host cells. the t3ss is composed of a cytoplasmic bulb, a basal body spanning the inner and outer bacterial membranes, and an extracellular needle. secretion is regulated by both cytoplasmic and inner membrane proteins that must respond to specific signals in order to ensure that virulence proteins are not secreted before contact with a euk ...	2008	18304577
geographic analysis of shigellosis in vietnam.	geographic and ecological analysis may provide investigators useful ecological information for the control of shigellosis. this paper provides distribution of individual shigella species in space, and ecological covariates for shigellosis in nha trang, vietnam. data on shigellosis in neighborhoods were used to identify ecological covariates. a bayesian hierarchical model was used to obtain joint posterior distribution of model parameters and to construct smoothed risk maps for shigellosis. neigh ...	2008	18296100