Publications

inhibitory spectra and modes of antimicrobial action of gallotannins from mango kernels (mangifera indica l.).	this study investigated the antimicrobial activities and modes of action of penta-, hexa-, hepta-, octa-, nona-, and deca-o-galloylglucose (gallotannins) isolated from mango kernels. the mics and minimum bactericidal concentrations (mbcs) against food-borne bacteria and fungi were determined using a critical dilution assay. gram-positive bacteria were generally more susceptible to gallotannins than were gram-negative bacteria. the mics of gallotannins against bacillus subtilis, bacillus cereus, ...	2011	21317249
mining high-throughput experimental data to link gene and function.	nearly 2200 genomes that encode around 6 million proteins have now been sequenced. around 40% of these proteins are of unknown function, even when function is loosely and minimally defined as 'belonging to a superfamily'. in addition to in silico methods, the swelling stream of high-throughput experimental data can give valuable clues for linking these unknowns with precise biological roles. the goal is to develop integrative data-mining platforms that allow the scientific community at large to ...	2011	21310501
t cell receptor recognition of self and foreign antigens in the induction of autoimmunity.	the major histocompatibility complex (mhc) on human chromosome 6 represents the most important genetic locus for a number of common human autoimmune diseases. specific alleles that differ from closely related alleles by only one or a few amino acids in the peptide binding groove are frequently strongly associated with disease susceptibility, raising the important question of which peptide presentation events are critical in disease initiation and progression. this review will cover a number of t ...	2011	21306912
role of the pjm1 plasmid-encoded transport proteins fatb, c and d in ferric anguibactin uptake in the fish pathogen vibrio anguillarum.	vibrio anguillarum serotype o1 is part of the natural flora in the aquatic habitat, but under certain circumstances it can cause terminal haemorrhagic septicemia in marine and fresh water fish due to the action of the anguibactin iron uptake system encoded by the virulence plasmid pjm1. this plasmid harbours the genes for the biosynthesis of the siderophore anguibactin and the ferric anguibactin transport proteins fatd, c, b and a encoded in the iron transport operon. the fata protein is the out ...	2010	21304833
in vitro antagonistic activity evaluation of lactic acid bacteria (lab) combined with cellulase enzyme against campylobacter jejuni growth in co-culture.	the antibacterial effects of nine lactic acid bacteria (lab) against campylobacter jejuni were investigated by using agar gel diffusion and co-culture assays. some differences were recorded between the inhibition effects measured with these two methods. only two lab, lb. pentosus cwbi b78 and e. faecium tht, exhibited a clear anti- campylobacter activity in co-culture assay with dehydrated poultry excreta mixed with ground straw (dpe/gs) as the only growth substrate source. it was observed that ...	2011	21301194
high-resolution melting system to perform multilocus sequence typing of campylobacter jejuni.	multi-locus sequence typing (mlst) has emerged as the state-of-the-art method for resolving bacterial population genetics but it is expensive and time consuming. we evaluated the potential of high resolution melting (hrm) to identify known mlst alleles of campylobacter jejuni at reduced cost and time. each mlst locus was amplified in two or three sub fragments, which were analyzed by hrm. the approach was investigated using 47 c. jejuni isolates, previously characterized by classical mlst, repre ...	2011	21297862
molecular risk assessment and epidemiological typing of shiga toxin-producing escherichia coli by using a novel pcr binary typing system.	shiga toxin-producing escherichia coli (stec) is a zoonotic pathogen that causes diarrheal disease in humans and is of public health concern because of its ability to cause outbreaks and severe disease such as hemorrhagic colitis or hemolytic-uremic syndrome. more than 400 serotypes of stec have been implicated in outbreaks and sporadic human disease. the aim of this study was to develop a pcr binary typing (p-bit) system that could be used to aid in risk assessment and epidemiological studies o ...	2011	21296939
antibacterial activity and mechanism of action of zinc oxide nanoparticles against campylobacter jejuni.	the antibacterial effect of zinc oxide (zno) nanoparticles on campylobacter jejuni was investigated for inhibition and inactivation of cell growth. the results showed that c. jejuni was extremely sensitive to treatment with zno nanoparticles. the mic of zno nanoparticles for c. jejuni was determined to be 0.05 to 0.025 mg/ml, which is 8- to 16-fold lower than that for salmonella enterica serovar enteritidis and escherichia coli o157:h7 (0.4 mg/ml). the action of zno nanoparticles against c. jeju ...	2011	21296935
prevalence of potentially neuropathic campylobacter jejuni strains on commercial broiler chicken products.	campylobacteriosis is the most common antecedent infection leading to the development of inflammatory neuropathies including guillain barré syndrome (gbs) and miller fisher syndrome (mfs), with alterations in surface proteins and genetic polymorphisms conferring increased risk. poultry is the most common source of c. jejuni infection in industrialized countries, including the us. there are no data on the prevalence on consumer poultry products of various strains of c. jejuni, including those hyp ...	2011	21295368
iqgap1 in microbial pathogenesis: targeting the actin cytoskeleton.	microbial pathogens cause widespread morbidity and mortality. central to the pathogens' virulence is manipulation of the host cell's cytoskeleton, which facilitates microbial invasion, multiplication, and avoidance of the innate immune response. iqgap1 is a ubiquitously expressed scaffold protein that integrates diverse signaling cascades. research has shown that iqgap1 binds to and modulates the activity of multiple proteins that participate in bacterial invasion. here, we review data that supp ...	2011	21295032
lipid raft redox signaling: molecular mechanisms in health and disease.	lipid rafts, the sphingolipid and cholesterol-enriched membrane microdomains, are able to form different membrane macrodomains or platforms upon stimulations, including redox signaling platforms, which serve as a critical signaling mechanism to mediate or regulate cellular activities or functions. in particular, this raft platform formation provides an important driving force for the assembling of nadph oxidase subunits and the recruitment of other related receptors, effectors, and regulatory co ...	2011	21294649
participation of cher and cheb in the chemosensory response of campylobacter jejuni.	campylobacter jejuni is a leading cause of bacterial gastroenteritis in humans and a commensal bacterium of the intestinal tracts of animals, especially poultry. chemotaxis is an important determinant for chicken colonization of c. jejuni. adaptation has a crucial role in the gradient-sensing mechanism that underlies chemotaxis. the genome sequence of c. jejuni reveals the presence of genes encoding putative adaptation proteins, cheb and cher. in-frame deletions of cheb, cher and chebr were cons ...	2011	21292743
rapid identification of gram-negative bacteria with and without ctx-m extended-spectrum ß-lactamase from positive blood culture bottles by pcr followed by microchip gel electrophoresis.	we evaluated the usefulness of pcr analysis of the 16s-23s rrna gene internal transcribed spacer (its) and the ctx-m extended-spectrum ß-lactamase (esbl) followed by microchip gel electrophoresis (mge) for direct identification and ctx-m detection of gram-negative bacteria (gnb) from positive blood culture bottles. of 251 gnb isolated from blood cultures containing a single bacterium, 225 (90%) were correctly identified at the species level directly from positive blood culture bottles by compari ...	2011	21289149
faecal calprotectin concentrations in apparently healthy children aged 0-12 years in urban kampala, uganda: a community-based survey.	calprotectin is a calcium and zinc binding protein, abundant in neutrophils and is extremely stable in faeces. faecal calprotectin is used as a non-specific marker for gastrointestinal inflammation. it has a good diagnostic precision to distinguish between irritable bowel syndrome and inflammatory bowel disease. studies have established normal concentrations in healthy children; all these studies have been performed in high-income countries. the objective of this study was to determine the conce ...	2011	21284894
standing genetic variation in contingency loci drives the rapid adaptation of campylobacter jejuni to a novel host.	the genome of the food-borne pathogen campylobacter jejuni contains multiple highly mutable sites, or contingency loci. it has been suggested that standing variation at these loci is a mechanism for rapid adaptation to a novel environment, but this phenomenon has not been shown experimentally. in previous work we showed that the virulence of c. jejuni nctc11168 increased after serial passage through a c57bl/6 il-10(-/-) mouse model of campylobacteriosis. here we sought to determine the genetic b ...	2011	21283682
investigations into the antiadhesive activity of herbal extracts against campylobacter jejuni.	campylobacter jejuni is one of the most common bacterial causes of diarrhoea in the industrialized world, being associated with the occurrence of guillain-barré syndrome, and inducing diseases partially through intestinal adherence. with increasing reports of c. jejuni drug resistance against standard antibiotics, investigations into antiadhesive agents for the prevention of bacterial infection are highly significant. given the consumer-driven development towards holistic and integrative healthc ...	2011	21280113
correlation of quantitative pcr for a poultry-specific brevibacterium marker gene with bacterial and chemical indicators of water pollution in a watershed impacted by land application of poultry litter.	the impact of fecal contamination from human and agricultural animal waste on water quality is a major public health concern. identification of the dominant source(s) of fecal pollution in a watershed is necessary for assessing the safety of recreational water and protecting water resources. a field study was conducted using quantitative pcr (qpcr) for the 16s rrna gene of brevibacterium sp. la35 to track feces-contaminated poultry litter in environmental samples. based on sensitivity and specif ...	2011	21278274
epidemiological association of different campylobacter jejuni groups with metabolism-associated genetic markers.	in this study, multilocus sequence typing (mlst) was combined with the genetic detection of six genetic markers, ansb, dmsa, ggt, cj1585c, cjj81176-1367/71 (cj1365c), and the two-gene marker tlp7 (cj0951c plus cj0952c), to assess if their presence correlated with different c. jejuni clonal groups. using a collection of 266 c. jejuni isolates from (in decreasing order of sample size) humans, chickens, cattle, and turkeys, it was further investigated whether the resulting genotypes correlated with ...	2011	21278270
campylobacter troglodytis sp. nov., isolated from feces of human-habituated wild chimpanzees (pan troglodytes schweinfurthii) in tanzania.	the transmission of simian immunodeficiency and ebola viruses to humans in recent years has heightened awareness of the public health significance of zoonotic diseases of primate origin, particularly from chimpanzees. in this study, we analyzed 71 fecal samples collected from 2 different wild chimpanzee (pan troglodytes) populations with different histories in relation to their proximity to humans. campylobacter spp. were detected by culture in 19/56 (34%) group 1 (human habituated for research ...	2011	21278267
novel virulence gene and clustered regularly interspaced short palindromic repeat (crispr) multilocus sequence typing scheme for subtyping of the major serovars of salmonella enterica subsp. enterica.	salmonella enterica subsp. enterica is the leading cause of bacterial food-borne disease in the united states. molecular subtyping methods are powerful tools for tracking the farm-to-fork spread of food-borne pathogens during outbreaks. in order to develop a novel multilocus sequence typing (mlst) scheme for subtyping the major serovars of s. enterica subsp. enterica, the virulence genes ssel and fimh and clustered regularly interspaced short palindromic repeat (crispr) loci were sequenced from ...	2011	21278266
synthesis and antimicrobial evaluation of nitazoxanide-based analogues: identification of selective and broad spectrum activity.	a library composed of nitazoxanide-based analogues was synthesized and assayed for increased antibacterial efficacy against the pyruvate-ferredoxin oxidoreductase (pfor) using microorganisms helicobacter pylori, campylobacter jejuni and clostridium difficile. derivatives were found to recapitulate and improve activity against these organisms and select analogues were tested for their ability to disrupt the pfor enzyme directly. the library was also screened for activity against staphylococci and ...	2010	21275058
neurologic symptoms associated with raising poultry and swine among participants in the agricultural health study.	guillain-barré syndrome (gbs) is the leading cause of acute peripheral neuropathy worldwide, often associated with recent foodborne infection with campylobacter jejuni. in this cross-sectional analysis of data from the agricultural health study, we tested whether swine and poultry exposure were associated with increased prevalence of gbs-like neurologic symptoms.	2011	21270654
guillain-barré syndrome subtypes related to campylobacter infection.	in guillain-barré syndrome (gbs), the diversity in electrophysiological subtypes is unexplained but may be determined by geographical factors and preceding infections. acute motor axonal neuropathy (aman) is a frequent gbs variant in japan and one study proposed that in japan, campylobacter jejuni infections exclusively elicit aman. in the netherlands c jejuni is the predominant type of preceding infection yet aman is rare. this may indicate that not all dutch gbs patients with c jejuni infectio ...	2011	21270063
campylobacter capsule and lipooligosaccharide confer resistance to serum and cationic antimicrobials.	the innate immune system plays a critical role in host defense against mucosal bacteria. campylobacter jejuni is a major cause of human gastroenteritis that usually resolves spontaneously within several days, suggesting that innate mechanisms are important to control the infection. however, the specific means by which this occurs is not well understood. while diarrheal isolates of c. jejuni usually are susceptible to human serum, we found that a systemic strain of c. jejuni, isolated from the ce ...	2011	21266840
evaluation of a cytolethal distending toxin (cdt) gene-based species-specific multiplex pcr assay for the identification of campylobacter strains isolated from diarrheal patients in japan.	we have developed a cytolethal distending toxin (cdt) gene-based species-specific multiplex pcr assay for the detection and identification of campylobacter jejuni, c. coli, and c. fetus. the applicability of this assay was evaluated with 325 campylobacter strains isolated from diarrheal patients in japan and the results were compared with those obtained by other genetic methods, including hipo gene detection and 16s rrna gene sequencing. of the 325 strains analyzed, 314 and 11 were identified as ...	2011	21266751
a d-peptide analog of the second extracellular loop of claudin-3 and -4 leads to mislocalized claudin and cellular apoptosis in mammary epithelial cells.	claudins are cell adhesion proteins thought to mediate cell-cell contacts at the tight junction. although a major role of claudins is to control paracellular diffusion, increasing evidence suggests that they may also function in tumor progression. to examine the role of the second extracellular loop in cell adhesion, a small peptide was designed, which mimics a conserved sequence, dfynp, within specific 'classic' claudin subtypes. using fluorescent indicators with mammary epithelial cells, treat ...	2011	21266016
four pcr primers necessary for the detection of periplasmic nitrate reductase genes in all groups of proteobacteria and in environmental dna.	generic primers are available for detecting bacterial genes required for almost every reaction of the biological nitrogen cycle, the one notable exception being napa (gene for the molybdoprotein of the periplasmic nitrate reductase) encoding periplasmic nitrate reductases. using an iterative approach, we report the first successful design of three forward oligonucleotide primers and one reverse primer that, in three separate pcrs, can amplify napa dna from all five groups of proteobacteria. all ...	2011	21265796
respiratory nitrogen metabolism and nitrosative stress defence in ?-proteobacteria: the role of nssr-type transcription regulators.	?-proteobacteria form a globally ubiquitous group of ecologically significant organisms and comprise a diverse range of host-associated and free-living species. to grow by anaerobic respiration, many ?-proteobacteria reduce nitrate to nitrite followed by either nitrite ammonification or denitrification. using the ammonifying model organisms wolinella succinogenes and campylobacter jejuni, the electron transport chains of nitrate respiration, respiratory nitrite ammonification and even n2o (nitro ...	2011	21265792
identification of a key amino acid of luxs involved in ai-2 production in campylobacter jejuni.	autoinducer-2 (ai-2) mediated quorum sensing has been associated with the expression of virulence factors in a number of pathogenic organisms and has been demonstrated to play a role in motility and cytolethal distending toxin (cdt) production in campylobacter jejuni. we have initiated the work to determine the molecular basis of ai-2 synthesis and the biological functions of quorum sensing in c. jejuni. in this work, two naturally occurring variants of c. jejuni 81116 were identified, one produ ...	2011	21264316
a single acidic residue can guide binding site selection but does not govern qacr cationic-drug affinity.	structures of the multidrug-binding repressor protein qacr with monovalent and bivalent cationic drugs revealed that the carboxylate side-chains of e90 and e120 were proximal to the positively charged nitrogens of the ligands ethidium, malachite green and rhodamine 6g, and therefore may contribute to drug neutralization and binding affinity. here, we report structural, biochemical and in vivo effects of substituting these glutamate residues. unexpectedly, substitutions had little impact on ligan ...	2011	21264225
hyperreflexic guillain-barré syndrome.	guillain-barré syndrome (gbs) is an acquired acute autoimmune polyradiculoneuropathy. the 2 features considered essential for the diagnosis of gbs are progressive motor weakness and areflexia. there have been several descriptions of reflex preservation and hyperreflexia in axonal variant of gbs in chinese, japanese, and european populations but it is not common in the indian subcontinent. we report 2 such cases discussing the pathophysiology and management aspects. this case report is to impress ...	2010	21264143
catheterization of intestinal loops in ruminants does not adversely affect loop function.	catheterized intestinal loops may be a valuable model to elucidate key components of the host response to various treatments within the small intestine of ruminants. we examined whether catheterizing ileal loops in sheep affected the overall health of animals and intestinal function, whether a bacterial treatment could be introduced into the loops through the catheters, and whether broad-spectrum antibiotics could sterilize the loops. escherichia coli cells transformed to express the gfp gene we ...	2010	21262134
a versatile and scalable strategy for glycoprofiling bifidobacterial consumption of human milk oligosaccharides.	human milk contains approximately 200 complex oligosaccharides believed to stimulate the growth and establishment of a protective microbiota in the infant gut. the lack of scalable analytical techniques has hindered the measurement of bacterial metabolism of these and other complex prebiotic oligosaccharides. an in vitro, multi-strain, assay capable of measuring kinetics of bacterial growth and detailed oligosaccharide consumption analysis by fticr-ms was developed and tested simultaneously on 1 ...	2009	21261928
mechanism of action of and resistance to quinolones.	fluoroquinolones are an important class of wide-spectrum antibacterial agents. the first quinolone described was nalidixic acid, which showed a narrow spectrum of activity. the evolution of quinolones to more potent molecules was based on changes at positions 1, 6, 7 and 8 of the chemical structure of nalidixic acid. quinolones inhibit dna gyrase and topoisomerase iv activities, two enzymes essential for bacteria viability. the acquisition of quinolone resistance is frequently related to (i) chr ...	2008	21261881
mechanism of action of and resistance to quinolones.	fluoroquinolones are an important class of wide-spectrum antibacterial agents. the first quinolone described was nalidixic acid, which showed a narrow spectrum of activity. the evolution of quinolones to more potent molecules was based on changes at positions 1, 6, 7 and 8 of the chemical structure of nalidixic acid. quinolones inhibit dna gyrase and topoisomerase iv activities, two enzymes essential for bacteria viability. the acquisition of quinolone resistance is frequently related to (i) chr ...	2008	21261881
massively parallel pathogen identification using high-density microarrays.	identification of microbial pathogens in clinical specimens is still performed by phenotypic methods that are often slow and cumbersome, despite the availability of more comprehensive genotyping technologies. we present an approach based on whole-genome amplification and resequencing microarrays for unbiased pathogen detection. this 10 h process identifies a broad spectrum of bacterial and viral species and predicts antibiotic resistance and pathogenicity and virulence profiles. we successfully ...	2008	21261824
massively parallel pathogen identification using high-density microarrays.	identification of microbial pathogens in clinical specimens is still performed by phenotypic methods that are often slow and cumbersome, despite the availability of more comprehensive genotyping technologies. we present an approach based on whole-genome amplification and resequencing microarrays for unbiased pathogen detection. this 10 h process identifies a broad spectrum of bacterial and viral species and predicts antibiotic resistance and pathogenicity and virulence profiles. we successfully ...	2008	21261824
quantifying the association between campylobacter infection and guillain-barré syndrome: a systematic review.	guillain-barré syndrome (gbs) is a neurologic disease that causes ascending paralysis and is triggered by a preceding bacterial or viral infection. several studies have shown that patients with gbs have a recent history of infection due to campylobacter jejuni. a literature review of published studies that reported rates of campylobacter infection before or in conjunction with gbs was done. these reported data were used for calculating the proportion of gbs cases who tested positive for campylob ...	2010	21261199
characterization of a t5-like coliphage, spc35, and differential development of resistance to spc35 in salmonella enterica serovar typhimurium and escherichia coli.	the potential of bacteriophage as an alternative biocontrol agent has recently been revisited due to the widespread occurrence of antibiotic-resistant bacteria. we isolated a virulent bacteriophage, spc35, that can infect both salmonella enterica serovar typhimurium and escherichia coli. morphological analysis by transmission electron microscopy and analysis of its 118,351-bp genome revealed that spc35 is a t5 group phage belonging to the family siphoviridae. btub, the outer membrane protein for ...	2011	21257810
lipooligosaccharide of campylobacter jejuni: similarity with multiple types of mammalian glycans beyond gangliosides.	campylobacter jejuni is well known for synthesizing ganglioside mimics within the glycan component of its lipooligosaccharide (los), which have been implicated in triggering guillain-barré syndrome. we now confirm that this pathogen is capable of synthesizing a much broader spectrum of host glycolipid/glycoprotein mimics within its los. p blood group and paragloboside (lacto-n-neotetraose) antigen mimicry is exhibited by rm1221, a strain isolated from a poultry source. rm1503, a gastroenteritis- ...	2011	21257763
fucosyltransferase 2 non-secretor and low secretor status predicts severe outcomes in premature infants.	to investigate secretor gene fucosyltransferase 2 (fut2) polymorphism and secretor phenotype in relation to outcomes of prematurity.	2011	21256510
microbial diagnostic microarray for food- and water-borne pathogens.	a microbial diagnostic microarray for the detection of the most relevant bacterial food- and water-borne pathogens and indicator organisms was developed and thoroughly validated. the microarray platform based on sequence-specific end labelling of oligonucleotides and the pyhylogenetically robust gyrb marker gene allowed a highly specific (resolution on genus/species level) and sensitive (0.1% relative and 10(4) cfu absolute detection sensitivity) detection of the target pathogens. validation was ...	2010	21255342
revolutionizing membrane protein overexpression in bacteria.	the bacterium escherichia coli is the most widely used expression host for overexpression trials of membrane proteins. usually, different strains, culture conditions and expression regimes are screened for to identify the optimal overexpression strategy. however, yields are often not satisfactory, especially for eukaryotic membrane proteins. this has initiated a revolution of membrane protein overexpression in bacteria. recent studies have shown that it is feasible to (i) engineer or select for ...	2010	21255339
genome (re-)annotation and open-source annotation pipelines.		2010	21255336
advances in campylobacter biology and implications for biotechnological applications.	campylobacter jejuni is a major foodborne pathogen of animal origin and a leading cause of bacterial gastroenteritis in humans. during the past decade, especially since the publication of the first c. jejuni genome sequence, major advances have been made in understanding the pathobiology and physiology of this organism. it is apparent that c. jejuni utilizes sophisticated mechanisms for effective colonization of the intestinal tracts in various animal species. although campylobacter is fragile i ...	2010	21255325
bacteriophage biocontrol in animals and meat products.	since their discovery almost a century ago, bacterial viruses (bacteriophages or 'phages') have been used to prevent and treat a multitude of bacterial infections (phage therapy: pt). in addition, they have been the basis for many advances in genetics and biochemistry. phage therapy was performed on human subjects in the united states, europe and asia in the few decades following their discovery. however, western countries largely abandoned pt in favour of antibiotics in the 1940s. the relativel ...	2009	21255295
new molecular tools for enhancing methane production, explaining thermodynamically limited lifestyles and other important biotechnological issues.		2009	21255285
role of a zn-independent dksa in zn homeostasis and stringent response.	dksa is a global transcriptional regulator that directly interacts with rna polymerase (rnap) and, in conjunction with an alarmone ppgpp, alters transcription initiation at target promoters. dksa proteins studied to date contain a canonical cys-4 zn-finger motif thought to be essential for their proper folding and thus activity. in addition to the canonical dksa protein, the pseudomonas aeruginosa genome encodes a closely related paralogue dksa2 that lacks the zn-finger motif. here, we report th ...	2010	21255113
role of a zn-independent dksa in zn homeostasis and stringent response.	dksa is a global transcriptional regulator that directly interacts with rna polymerase (rnap) and, in conjunction with an alarmone ppgpp, alters transcription initiation at target promoters. dksa proteins studied to date contain a canonical cys-4 zn-finger motif thought to be essential for their proper folding and thus activity. in addition to the canonical dksa protein, the pseudomonas aeruginosa genome encodes a closely related paralogue dksa2 that lacks the zn-finger motif. here, we report th ...	2010	21255113
pas/poly-hamp signalling in aer-2, a soluble haem-based sensor.	poly-hamp domains are widespread in bacterial chemoreceptors, but previous studies have focused on receptors with single hamp domains. the pseudomonas aeruginosa chemoreceptor, aer-2, has an unusual domain architecture consisting of a pas-sensing domain sandwiched between three n-terminal and two c-terminal hamp domains, followed by a conserved kinase control module. the structure of the n-terminal hamp domains was recently solved, making aer-2 the first protein with resolved poly-hamp structure ...	2010	21255112
pas/poly-hamp signalling in aer-2, a soluble haem-based sensor.	poly-hamp domains are widespread in bacterial chemoreceptors, but previous studies have focused on receptors with single hamp domains. the pseudomonas aeruginosa chemoreceptor, aer-2, has an unusual domain architecture consisting of a pas-sensing domain sandwiched between three n-terminal and two c-terminal hamp domains, followed by a conserved kinase control module. the structure of the n-terminal hamp domains was recently solved, making aer-2 the first protein with resolved poly-hamp structure ...	2010	21255112
global transcriptional analysis of spontaneous sakacin p-resistant mutant strains of listeria monocytogenes during growth on different sugars.	subclass iia bacteriocins have strong antilisterial activity and can control the growth of listeria monocytogenes in food. however, l. monocytogenes may develop resistance towards such bacteriocins. in this follow-up study, the transcriptomes of a high level (l502-1) and a low level (l502-6) spontaneous sakacin p-resistant mutant strain of l. monocytogenes were compared to the wild-type (l502). the growth of the resistant strains was reduced on mannose but not affected on cellobiose and the tran ...	2011	21253597
two new subfamilies of dna mismatch repair proteins (muts) specifically abundant in the marine environment.	muts proteins are ubiquitous in cellular organisms and have important roles in dna mismatch repair or recombination. in the virus world, the amoeba-infecting mimivirus, as well as the recently sequenced cafeteria roenbergensis virus are known to encode a muts related to the homologs found in octocorals and ɛ-proteobacteria. to explore the presence of muts proteins in other viral genomes, we performed a genomic survey of four giant viruses ('giruses') (pyramimonas orientalis virus (pov), phaeocys ...	2011	21248859
the rtxa toxin gene of kingella kingae: a pertinent target for molecular diagnosis of osteoarticular infections.	kingella kingae is an emerging osteoarticular pathogen in young children. its isolation by traditional culture methods remains difficult, underscoring the need to implement other diagnostic methods for its detection and identification, such as nucleic acid amplification tests. although the genome of this bacterium has not yet been sequenced, a toxin named rtx has been identified. the goal of this study was to develop sensitive, specific, and rapid molecular methods based on the rtxa toxin gene s ...	2011	21248099
brain angiogenesis inhibitor 1 (bai1) is a pattern recognition receptor that mediates macrophage binding and engulfment of gram-negative bacteria.	bacterial recognition by host cells is essential for initiation of infection and the host response. bacteria interact with host cells via multiple pattern recognition receptors that recognize microbial products or pathogen-associated molecular patterns. in response to this interaction, host cell signaling cascades are activated that lead to inflammatory responses and/or phagocytic clearance of attached bacteria. brain angiogenesis inhibitor 1 (bai1) is a receptor that recognizes apoptotic cells ...	2011	21245295
comprehensive approaches to molecular biomarker discovery for detection and identification of cronobacter spp. (enterobacter sakazakii) and salmonella spp.	cronobacter spp. (formerly enterobacter sakazakii) and salmonella spp. are increasingly implicated internationally as important microbiological contaminants in low-moisture food products, including powdered infant formula. estimates indicate that 40 to 80% of infants infected with cronobacter sakazakii and/or salmonella in the united states may not survive the illness. a systematic approach, combining literature-based data mining, comparative genome analysis, and the direct sequencing of pcr pro ...	2011	21239552
persistence of free-living protozoan communities across rearing cycles in commercial poultry houses.	the introduction and survival of zoonotic bacterial pathogens in poultry farming have been linked to bacterial association with free-living protozoa. to date, however, no information is available on the persistence of protozoan communities in these environments across consecutive rearing cycles and how it is affected by farm- and habitat-specific characteristics and management strategies. we therefore investigated the spatial and temporal dynamics of free-living protozoa in three habitats (pipel ...	2011	21239551
survival of escherichia coli, enterococci, and campylobacter spp. in sheep feces on pastures.	the survival of enteric bacteria in 10 freshly collected sheep fecal samples on pastures was measured in each of four seasons. ten freshly collected feces were placed on pasture, and concentrations of escherichia coli, enterococci, and campylobacter spp. were monitored until exhaustion of the fecal samples. in all four seasons, there was an increase in enterococcal concentrations by up to 3 orders of magnitude, with peak concentrations recorded between 11 and 28 days after deposition. e. coli co ...	2011	21239546
challenges of campylobacter jejuni in poultry production.		2010	21236509
taxonomy, epidemiology, and clinical relevance of the genus arcobacter.	the genus arcobacter, defined almost 20 years ago from members of the genus campylobacter, has become increasingly important because its members are being considered emergent enteropathogens and/or potential zoonotic agents. over recent years information that is relevant for microbiologists, especially those working in the medical and veterinary fields and in the food safety sector, has accumulated. recently, the genus has been enlarged with several new species. the complete genomes of arcobacte ...	2011	21233511
galleria mellonella as an infection model for campylobacter jejuni virulence.	larvae of galleria mellonella (greater wax moth) have been shown to be susceptible to campylobacter jejuni infection and our study characterizes this infection model. following infection with c. jejuni human isolates, bacteria were visible in the haemocoel and gut of challenged larvae, and there was extensive damage to the gut. bacteria were found in the extracellular and cell-associated fraction in the haemocoel, and it was shown that c. jejuni can survive in insect cells. finally, we have used ...	2011	21233296
evolving promiscuously.		2011	21224414
antibiotic prophylaxis prevents the development of a post-infectious phenotype in a new rat model of post-infectious ibs.	a recent post-infectious rat model with campylobacter jejuni 81-176 has replicated the events noted in humans with post-infectious irritable bowel syndrome (ibs). in this study, we test whether prophylactic treatment with the antibiotic rifaximin will prevent the development of long-term altered bowel function in this model.	2011	21222158
adherence, invasion, toxigenic, and chemotactic properties of mexican campylobacter strains.	to determine the virulence factors of mexican wild-type strains of campylobacter jejuni and campylobacter coli, 31 wild-type strains were isolated from food and from humans. the production of cytolethal distending toxin and the adherence and invasion capabilities of these strains were assayed in vero cells. hard agar plugs with repellents and attractants were used to examine chemotaxis. mueller-hinton agar with supplements was used for motility analysis and to measure hemolytic activity. nine st ...	2010	21219724
systematic analysis of cyclic di-gmp signalling enzymes and their role in biofilm formation and virulence in yersinia pestis.	cyclic di-gmp (c-di-gmp) is a signalling molecule that governs the transition between planktonic and biofilm states. previously, we showed that the diguanylate cyclase hmst and the putative c-di-gmp phosphodiesterase hmsp inversely regulate biofilm formation through control of hmshfrs-dependent poly-β-1,6-n-acetylglucosamine synthesis. here, we systematically examine the functionality of the genes encoding putative c-di-gmp metabolic enzymes in yersinia pestis. we determine that, in addition to ...	2010	21219468
systematic analysis of cyclic di-gmp signalling enzymes and their role in biofilm formation and virulence in yersinia pestis.	cyclic di-gmp (c-di-gmp) is a signalling molecule that governs the transition between planktonic and biofilm states. previously, we showed that the diguanylate cyclase hmst and the putative c-di-gmp phosphodiesterase hmsp inversely regulate biofilm formation through control of hmshfrs-dependent poly-β-1,6-n-acetylglucosamine synthesis. here, we systematically examine the functionality of the genes encoding putative c-di-gmp metabolic enzymes in yersinia pestis. we determine that, in addition to ...	2010	21219468
complete genome sequence of campylobacter jejuni strain s3.	campylobacter jejuni is one of the leading causes of bacterial gastroenteritis in the world; however, there is only one complete genome sequence of a poultry strain to date. here we report the complete genome sequence and annotation of the second poultry strain, c. jejuni strain s3. this strain has been shown to be nonmotile, to be a poor invader in vitro, and to be a poor colonizer of poultry after minimal in vitro passage.	2011	21217004
glycosylation is required for outer membrane localization of the lectin lecb in pseudomonas aeruginosa.	the fucose-/mannose-specific lectin lecb from pseudomonas aeruginosa is transported to the outer membrane; however, the mechanism used is not known so far. here, we report that lecb is present in the periplasm of p. aeruginosa in two variants of different sizes. both were functional and could be purified by their affinity to mannose. the difference in size was shown by a specific enzyme assay to be a result of n glycosylation, and inactivation of the glycosylation sites was shown by site-directe ...	2011	21217000
arcobacter population dynamics in pigs on farrow-to-finish farms.	healthy pigs are an important reservoir for the emerging human pathogen arcobacter which can result in contamination of porcine carcasses and pork and the spread of arcobacters into the environment. up to now, the excretion of arcobacters by pigs has been studied, but information about the transmission routes in fattening pigs is lacking. the present study aimed to elucidate the arcobacter population dynamics in pigs during the fattening period on four farrow-to-finish farms. on each farm, 30 cl ...	2011	21216902
detection, isolation, and characterization of helicobacter species from the gastrointestinal tract of the brushtail possum.	the presence of helicobacter species in australian marsupials was examined systematically using microscopy, culture, and pcr in different regions of the gastrointestinal tract (git) and in the liver of brushtail possums (btps) (trichosurus vulpecula), a common australian marsupial that feeds on eucalyptus leaves. the spatial distribution of helicobacter species in the git sections also was examined microscopically in silver-stained sections and by fluorescent in situ hybridization (fish) using a ...	2011	21216901
enteric pathogen exploitation of the microbiota-generated nutrient environment of the gut.	residing within the intestine is a large community of commensal organisms collectively termed the microbiota. this community generates a complex nutrient environment by breaking down indigestible food products into metabolites that are used by both the host and the microbiota. both the invading intestinal pathogen and the microbiota compete for these metabolites, which can shape both the composition of the flora, as well as susceptibility to infection. after infection is established, pathogen me ...	2011	21215681
globin-mediated nitric oxide detoxification in the foodborne pathogenic bacterium campylobacter jejuni proceeds via a dioxygenase or denitrosylase mechanism.	nitric oxide (no()) is a toxin, but bacteria have evolved various strategies to detoxify this harmful radical to nitrate, the best known mechanism being the dioxygenase reaction of bacterial flavohaemoglobins. in addition, globins can form oxoferryl (fe(iv)o) species through the reaction of the ferric haem with hydrogen peroxide: these species can also detoxify no() to nitrite and nitrate. during infection, campylobacter is exposed to both no() and hydrogen peroxide. a question therefore arises: ...	2011	21215320
no evidence of infection with avian influenza viruses among us poultry workers in the delmarva peninsula, maryland and virginia, usa.	industrial poultry workers may be at elevated risk of avian influenza infection due to intense occupational contact with live poultry. serum samples from poultry workers and community members in the delmarva peninsula, one of the densest regions of poultry production in the united states, were analyzed for antibodies to strains of five avian influenza subtypes using microneutralization assays. no evidence of infection was found, suggesting inefficient transmission to humans or the absence of vir ...	2011	21213164
contagious cancer.	although cancer can on occasion be caused by infectious agents such as specific bacteria, parasites, and viruses, it is not generally considered a transmissible disease. in rare circumstances, however, direct communication from one host to another has been documented. the tasmanian devil is now threatened with extinction in the wild because of a fatal transmissible cancer, devil facial tumor disease (dftd). another example is canine transmissible venereal tumor (ctvt or sticker's sarcoma) in dog ...	2011	21212437
a prospective study of acute diarrhea in a cohort of united states military personnel on deployment to the multinational force and observers, sinai, egypt.	to better understand the epidemiology of diarrhea in deployed personnel to the middle east, a prospective cohort study of travelers' diarrhea (td) was conducted between may 2004 and january 2005 at the multinational force and observers (mfo) camp in the southern sinai. a baseline entry questionnaire and stool specimen was provided on study entry, and volunteers were followed every 6 weeks. of 211 volunteers, 145 (68.7%) completed one or more follow-up visits. in total, 416 follow-up surveys were ...	2011	21212203
introgression in the genus campylobacter: generation and spread of mosaic alleles.	horizontal genetic exchange strongly influences the evolution of many bacteria, substantially contributing to difficulties in defining their position in taxonomic groups. in particular, how clusters of related bacterial genotypes - currently classified as microbiological species - evolve and are maintained remains controversial. the nature and magnitude of gene exchange between two closely related (approx. 15 % nucleotide divergence) microbiologically defined species, campylobacter jejuni and ca ...	2011	21212120
influence of tetracycline resistance on the transport of manure-derived escherichia coli in saturated porous media.	in this research, tetracycline resistant (tet(r)) and tetracycline susceptible (tet(s)) escherichia coli isolates were retrieved from dairy manure and the influence of tetracycline resistance on the transport of e. coli in saturated porous media was investigated through laboratory column transport experiments. experimental results showed that tet(r)e. coli strains had higher mobility than the tet(s) strains in saturated porous media. measurements of cell surface properties suggested that tet(r)e ...	2010	21211813
influence of tetracycline resistance on the transport of manure-derived escherichia coli in saturated porous media.	in this research, tetracycline resistant (tet(r)) and tetracycline susceptible (tet(s)) escherichia coli isolates were retrieved from dairy manure and the influence of tetracycline resistance on the transport of e. coli in saturated porous media was investigated through laboratory column transport experiments. experimental results showed that tet(r)e. coli strains had higher mobility than the tet(s) strains in saturated porous media. measurements of cell surface properties suggested that tet(r)e ...	2010	21211813
new methods for detection of campylobacters in stool samples in comparison to culture.	campylobacter species, especially campylobacter jejuni and campylobacter coli, are a major cause of human bacterial enteritis. current detection in stools is done essentially by culture on selective and nonselective media with filtration. these methods were compared to 2 molecular biology methods, an in-house real-time pcr and a multiplex pcr named seeplex diarrhea ace detection, and 3 immunoenzymatic methods, premier campy, ridascreen campylobacter, and immunocard stat!campy. out of 242 stool s ...	2011	21209172
rapid stool-based diagnosis of clostridium difficile infection by real-time pcr in a children's hospital.	clostridium difficile is a major cause of nosocomial antibiotic-associated infectious diarrhea and pseudomembranous colitis. detection of c. difficile by anaerobic bacterial culture and/or cytotoxicity assays has been largely replaced by rapid enzyme immunoassays (eia). however, due to the lack of sensitivity of stool eia, we developed a multiplex real-time pcr assay targeting the c. difficile toxin genes tcda and tcdb. stool samples from hospitalized pediatric patients suspected of having c. di ...	2011	21209161
comparison of bruker biotyper matrix-assisted laser desorption ionization-time of flight mass spectrometer to bd phoenix automated microbiology system for identification of gram-negative bacilli.	we compared the bd phoenix automated microbiology system to the bruker biotyper (version 2.0) matrix-assisted laser desorption ionization-time of flight (maldi-tof) mass spectrometry (ms) system for identification of gram-negative bacilli, using biochemical testing and/or genetic sequencing to resolve discordant results. the bd phoenix correctly identified 363 (83%) and 330 (75%) isolates to the genus and species level, respectively. the bruker biotyper correctly identified 408 (93%) and 360 (82 ...	2011	21209160
expression, purification, crystallization and preliminary x-ray analysis of wild-type and of an active-site mutant of glyceraldehyde-3-phosphate dehydrogenase from campylobacter jejuni.	the genome of the enteric pathogen campylobacter jejuni encodes a single glyceraldehyde-3-phosphate dehydrogenase that can utilize either nadp+ or nad+ as coenzymes for the oxidative phosphorylation of glyceraldehyde-3-phosphate to 1,3-diphosphoglycerate. here, the cloning, expression, purification, crystallization and preliminary x-ray analysis of both the wild type and an active-site mutant of the enzyme are presented. preliminary x-ray analysis revealed that in both cases the crystals diffrac ...	2010	21206028
has the microbiota played a critical role in the evolution of the adaptive immune system?	although microbes have been classically viewed as pathogens, it is now well established that the majority of host-bacterial interactions are symbiotic. during development and into adulthood, gut bacteria shape the tissues, cells, and molecular profile of our gastrointestinal immune system. this partnership, forged over many millennia of coevolution, is based on a molecular exchange involving bacterial signals that are recognized by host receptors to mediate beneficial outcomes for both microbes ...	2010	21205662
contamination level and ingestion dose of foodborne pathogens associated with infections.	summaryintake of a small dose of foodborne pathogens can cause infection. in this study, an estimation of the infectious dose of the pathogens was obtained by conducting microbiological risk assessments. the contamination levels of foodborne pathogens were analysed in 17 outbreaks of salmonella, escherichia coli o157, enterotoxigenic e. coli, vibrio parahaemolyticus, and campylobacter jejuni occurring in japan between 2004 and 2006. the infectious dose was estimated in 14 of the 17 outbreaks uti ...	2010	21205441
expression and characterization of cell-signalling molecules in campylobacter jejuni.	this study investigated the production and effects of cell-signalling compounds on selected survival and virulence mechanisms of campylobacter jejuni.	2011	21205102
multiplex pcr assay for the detection and quantification of campylobacter spp., escherichia coli o157:h7, and salmonella serotypes in water samples.	three pathogens, campylobacter, salmonella, and shiga-toxin-producing escherichia coli, are leading causes of bacterial gastroenteritis in the united states and worldwide. although these three bacteria are typically considered food-borne pathogens, outbreaks have been reported due to contaminated drinking water and irrigation water. the aim of this research was to develop two types of pcr assays that could detect and quantify three pathogens, campylobacter spp., e. coli o157:h7, and salmonella s ...	2011	21204924
nonthermal dielectric-barrier discharge plasma-induced inactivation involves oxidative dna damage and membrane lipid peroxidation in escherichia coli.	oxidative stress leads to membrane lipid peroxidation, which yields products causing variable degrees of detrimental oxidative modifications in cells. reactive oxygen species (ros) are the key regulators in this process and induce lipid peroxidation in escherichia coli. application of nonthermal (cold) plasma is increasingly used for inactivation of surface contaminants. recently, we reported a successful application of nonthermal plasma, using a floating-electrode dielectric-barrier discharge ( ...	2011	21199923
the no-responsive hemoglobins of campylobacter jejuni: concerted responses of two globins to no and evidence in vitro for globin regulation by the transcription factor nssr.	campylobacter jejuni possesses no-responsive and -detoxifying mechanisms to survive no during transmission and pathogenesis. c. jejuni possesses two hemoglobins. the first (cgb) is a single-domain (non-flavo)hemoglobin encoded by gene cj1586 (cgb), mutation of which leads to hypersensitivity to s-nitrosoglutathione and no. transcription of cgb is induced by nitrosative stress and confers resistance to no, presumably via a cgb-catalyzed dioxygenase or denitrosylase reaction that converts no and o ...	2011	21199674
campylobacter jejuni is not an important pathogen as a cause of diarrhea in us travelers to mexico.	campylobacter jejuni is an unusual cause of travelers' diarrhea acquired in mexico, but previous studies have relied only on stool culture for diagnosis. we conducted a cohort study to determine if antibody seroconversion to c jejuni would better reflect the occurrence of infection acquired in mexico. serum igg, iga, and igm antibodies to campylobacter seroconverted in only 2 of 353 participants (0.6%). these data further support that c jejuni infection is an unusual cause of travelers' diarrhea ...	2010	21199144
immunology of gut mucosal vaccines.	understanding the mechanisms underlying the induction of immunity in the gastrointestinal mucosa following oral immunization and the cross-talk between mucosal and systemic immunity should expedite the development of vaccines to diminish the global burden caused by enteric pathogens. identifying an immunological correlate of protection in the course of field trials of efficacy, animal models (when available), or human challenge studies is also invaluable. in industrialized country populations, l ...	2011	21198669
guillain-barré syndrome animal model: the first proof of molecular mimicry in human autoimmune disorder.	molecular mimicry between self and microbial components has been proposed as the pathogenic mechanism of autoimmune diseases, and this hypothesis is proven in guillain-barré syndrome. guillain-barré syndrome, the most frequent cause of acute neuromuscular paralysis, sometimes occurs after campylobacter jejuni enteritis. gangliosides are predominantly cell-surface glycolipids highly expressed in nervous tissue, whilst lipo-oligosaccharides are major components of the gram-negative bacterium c. je ...	2010	21197269
viability of bacillus licheniformis and bacillus thuringiensis spores as a model for predicting the fate of bacillus anthracis spores during composting of dead livestock.	safe disposal of dead livestock and contaminated manure is essential for the effective control of infectious disease outbreaks. composting has been shown to be an effective method of disposal, but no information exists on its ability to contain diseases caused by spore-forming bacteria, such as bacillus anthracis. duplicate composters (east and west), each containing 16 dead cattle, were constructed (final capacity, 85,000 kg). spores (10(7) cfu/g manure) of bacillus licheniformis and bacillus t ...	2010	21193674
viability of bacillus licheniformis and bacillus thuringiensis spores as a model for predicting the fate of bacillus anthracis spores during composting of dead livestock.	safe disposal of dead livestock and contaminated manure is essential for the effective control of infectious disease outbreaks. composting has been shown to be an effective method of disposal, but no information exists on its ability to contain diseases caused by spore-forming bacteria, such as bacillus anthracis. duplicate composters (east and west), each containing 16 dead cattle, were constructed (final capacity, 85,000 kg). spores (10(7) cfu/g manure) of bacillus licheniformis and bacillus t ...	2010	21193674
metallic copper as an antimicrobial surface.	bacteria, yeasts, and viruses are rapidly killed on metallic copper surfaces, and the term "contact killing" has been coined for this process. while the phenomenon was already known in ancient times, it is currently receiving renewed attention. this is due to the potential use of copper as an antibacterial material in health care settings. contact killing was observed to take place at a rate of at least 7 to 8 logs per hour, and no live microorganisms were generally recovered from copper surface ...	2010	21193661
metallic copper as an antimicrobial surface.	bacteria, yeasts, and viruses are rapidly killed on metallic copper surfaces, and the term "contact killing" has been coined for this process. while the phenomenon was already known in ancient times, it is currently receiving renewed attention. this is due to the potential use of copper as an antibacterial material in health care settings. contact killing was observed to take place at a rate of at least 7 to 8 logs per hour, and no live microorganisms were generally recovered from copper surface ...	2010	21193661
phenotypic and genotypic evidence for l-fucose utilization by campylobacter jejuni.	campylobacter jejuni remains among the leading causes of bacterial food-borne illness. the current understanding of campylobacter physiology suggests that it is asaccharolytic and is unable to catabolize exogenous carbohydrates. contrary to this paradigm, we provide evidence for l-fucose utilization by c. jejuni. the fucose phenotype, shown in chemically defined medium, is strain specific and linked to an 11-open reading frame (orf) plasticity region of the bacterial chromosome. by constructing ...	2010	21193610
rapid detection of fluoroquinolone-resistant and heteroresistant mycobacterium tuberculosis by use of sloppy molecular beacons and dual melting-temperature codes in a real-time pcr assay.	fluoroquinolones (fq) are important second-line drugs to treat tuberculosis; however, fq resistance is an emerging problem. resistance has been mainly attributed to mutations in a 21-bp region of the mycobacterium tuberculosis gyra gene, often called the quinolone resistance-determining region (qrdr). we have developed a simple, rapid, and specific assay to detect fq resistance-determining qrdr mutations. the assay amplifies the m. tuberculosis gyra qrdr in an asymmetrical pcr followed by probin ...	2010	21191047
carbon load in aquatic ecosystems affects the diversity and biomass of water biofilm consortia and the persistence of the pathogen campylobacter jejuni within them.	the influence of carbon load on autochthonous water microflora population distribution and diversity, and on the persistence of campylobacter jejuni, was examined with a two-stage aquatic biofilm model. serine was chosen since it is a carbon source utilised by c. jejuni and concentrations were chosen to reflect upper limits of amino acid load reported in surface water. the total viable count of the autochthonous biofilm microflora increased with increasing serine concentration (10-fold and 20-fo ...	1998	21182705
management of the returning traveler with diarrhea.	traveler's diarrhea (td) strikes 20-60% of travelers visiting developing countries. it occurs shortly after the return and can be distinguished into two categories: acute and persistent td. acute td, mostly caused by bacterial and viral pathogens, is usually mild and self-limited, and deserves empirical symptomatic and/or antibiotic therapy in selected cases. fluoroquinolones are progressively superseded in this indication by azithromycin, a well tolerated macrolide active against most bacteria ...	2009	21180583
evolution of an agriculture-associated disease causing campylobacter coli clade: evidence from national surveillance data in scotland.	the common zoonotic pathogen campylobacter coli is an important cause of bacterial gastroenteritis worldwide but its evolution is incompletely understood. using multilocus sequence type (mlst) data of 7 housekeeping genes from a national survey of campylobacter in scotland (2005/6), and a combined population genetic-phylogenetics approach, we investigated the evolutionary history of c. coli. genealogical reconstruction of isolates from clinical infection, farm animals and the environment, reveal ...	2010	21179537