Publications

TitleAbstractYear
Filter
PMID(sorted descending)
Filter
increased production of suilysin contributes to invasive infection of the streptococcus suis strain 05zyh33.streptococcus suis serotype 2 (ss2) is widely recognized in the veterinary world as the cause of rapidly progressive and fatal sepsis in infant pigs, manifested with meningitis, polyarthritis and pneumonia. it has evolved into a highly infectious strain, and caused two large-scale outbreaks of human epidemic in china, characterized bytypical toxic-shock syndrome and invasive infection. however, the molecular basis of virulence of this emerging zoonotic pathogen is still largely unknown. the pres ...201425241621
development of an appropriate pcr system for the reclassification of streptococcus suis.thirty-five serotypes of streptococcus suis (serotypes 1-34 and serotype 1/2) have so far been described on the basis of their polysaccharide capsular antigens. however, in the last decade, some serotype reference strains have been reexamined for their taxonomic status, and the reference strains of serotypes 20, 22, 26, 32, 33, and 34 may be different from taxon s. suis. in the present study, we developed a novel pcr method targeting the recombination/repair protein (recn) gene of s. suis, desig ...201425229648
construction, characterization and evaluation of the protective efficacy of the streptococcus suis double mutant strain δsspep/δsspspc as a live vaccine candidate in mice.streptococcus suis serotype 2 (s. suis 2) causes sepsis and meningitis in piglets and humans, and results in one of the most serious bacterial diseases affecting the production of commercial pigs around the world. due to the failure of the current inactivated vaccine to protect against the disease, development of a new attenuated live vaccine against s. suis 2 by deleting essential virulence factors is urgently needed. we have previously reported the construction and characterization of an sspep ...201525220429
[acute bacterial meningitis as an occupational disease].streptococcus suis is a zoonotic pathogen with worldwide distribution, responsible for more than 700 human cases globally reported. this infection affects mostly men, exposed to pig or pork, which leads to its usual classification as an occupational disease. we report a case of acute bacterial meningitis in a 44 years old male. according to his past medical history, the patient had chronic alcoholism and worked in a restaurant as a piglet roaster. microbiological examination of blood and csf rev ...201425203963
assessment of the pathogenesis of streptococcus suis type 2 infection in piglets for understanding streptococcal toxic shock-like syndrome, meningitis, and sequelae.streptococcus suis type 2 (ss2) is an zoonotic pathogen that had caused outbreaks in 1998 and 2005 in china. it is still not very clear how the disease progresses into the streptococcal toxic shock-like syndrome (stsls) or meningitis, as well as the sequelae from the survivals. the present study used piglets as infection model to systematically investigate the pathogenesis of the infection caused by the ss2 strain 05zyh33. the infected piglets showed joint swelling, lameness, and crouch at begin ...201425200597
identification and characterisation a surface-associated arginine peptidase in streptococcus suis serotype 2.streptococcus suis is an important zoonotic pathogen worldwide and is responsible for disease in swine and humans. in the present study, we identified and characterised a surface-associated peptidase (abpb, amylase-binding protein b) in streptococcus suis serotype 2 (s. suis 2) that has high hydrolytic activity towards h-arg-pna, with maximum activity at ph 7.0. stimulation of raw 264.7 macrophages with purified recombinant abpb protein triggered the release of pro-inflammatory cytokines. an abp ...201525179447
the arginine-ornithine antiporter arcd contributes to biological fitness of streptococcus suis.the arginine-ornithine antiporter (arcd) is part of the arginine deiminase system (ads), a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen streptococcus suis. the ads has recently been shown to play a role in the pathogenicity of s. suis, in particular in its survival in host cells. the contribution of arginine and arginine transport mediated by arcd, however, has yet to be clarified. in the present study, we showed b ...201425161959
breed-specific transcriptome response of spleen from six to eight week old piglet after infection with streptococcus suis type 2.different pig breeds have shown differential susceptibility to the pathogen infection; however, molecular mechanisms of the infection susceptibility are not fully understood. streptococcus suis type 2 (ss2) is an important zoonotic pathogen. to identify the genes responsible for infection susceptibility, pigs from two different breeds (enshi black and landrace) were inoculated with ss2 and their spleen transcriptome profiles were investigated in the present study. the differentially expressed ge ...201425160908
whole-genome sequence of streptococcus suis serotype 4 reference strain 6407.we report here the second complete genome sequence of streptococcus suis serotype 4 (strain 6407). the genome is 2,292,360 bp in length, covering 2,239 coding sequences, 58 trnas, and 4 rrna loci.201425125641
a cluster of streptococcus suis meningitis in a family who traveled to taiwan from southern vietnam. 201625081989
genetic diversity of streptococcus suis isolated from three pig farms of china obtained by acquiring antibiotic resistance genes.acquiring antibiotic resistance genes may change an organism's genetic characteristics and the effect of antibiotics, resulting in a rapid transmission of microbial pathogens. the objectives of this experiment were to identify the features of streptococcus suis (s. suis) isolated from three pig farms in china which are geographically isolated.201525060787
population analysis of streptococcus suis isolates from slaughtered swine by use of minimum core genome sequence typing.streptococcus suis, an important zoonotic pathogen, is a highly diverse species with only a subset of strains that cause disease in humans. our previous study proposed a minimum core genome (mcg) sequence typing method and defined seven mcg groups, with mcg group 1 as the prevalent group causing human infections. in this study, we identified a set of 10 single nucleotide polymorphisms (snps) distributed in six genes that were used to identify the seven mcg groups. the 10 snps were typed for 179 ...201425056323
catabolite control protein a is an important regulator of metabolism in streptococcus suis type 2.streptococcus suis (s. suis) type 2 is an extremely important gram-positive bacterial pathogen that can cause human or swine endocarditis, meningitis, bronchopneumonia, arthritis and sepsis. catabolite control protein a (ccpa) is a major transcriptional regulator in s. suis type 2 that functions in catabolite control, specifically during growth on glucose or galactose. the regulation of central metabolism can affect the virulence of bacteria. in the present study, a metabolomics approach was use ...201425054015
characterization of dnase activity and gene in streptococcus suis and evidence for a role as virulence factor.the gram-positive bacterium streptococcus suis serotype 2 is an important swine pathogen and emerging zoonotic agent. multilocus sequence typing allowed dividing s. suis serotype 2 into sequence types (sts). the three major sts of s. suis serotype 2 from north america are 1 (most virulent), 25 (intermediate virulence) and 28 (less virulent). although the presence of dnase activity in s. suis has been previously reported, little data is available. the aim of this study was to investigate dnase ac ...201424996230
the truncated major pilin subunit sbp2 of the srtbcd pilus cluster still contributes to streptococcus suis pathogenesis in the absence of pilus shaft.streptococcus suis serotype 2 (ss2) is an emerging zoonotic agent responsible for a number of infections in pigs and humans. pili have been proposed as virulence factors in gram-positive bacteria. however, due to the abolition of pili production, the function of the srtbcd pilus cluster, especially the truncated major pilin subunit sbp2 (sbp2', sbp2″), has not been explored. in this study, isogenic mutants (δsbp2', δsbp2″) were constructed by homologous replacement in ss2 strain p1/7. deletion o ...201424989484
heat incubation inactivates streptococcal exotoxins and recombinant cholesterol-dependent cytolysins: suilysin, pneumolysin and streptolysin o.streptococcus species release cholesterol-dependent cytolysins (cdcs), which are a main toxin, and their heat susceptibility is poorly understood. the aim of this study was to clarify the heat susceptibility of streptococcal exotoxins and cdcs. streptococcal exotoxins were treated with heat incubation at 60 °c for 10 or 30 min. the streptococcus suis exotoxin of serotypes 1 and 2 exhibited more than 50 % haemolytic activity, and all streptococcus pneumoniae exotoxins exhibited more than 60 % hae ...201424974216
suicin 90-1330 from a nonvirulent strain of streptococcus suis: a nisin-related lantibiotic active on gram-positive swine pathogens.streptococcus suis serotype 2 is known to cause severe infections (meningitis, endocarditis, and septicemia) in pigs and is considered an emerging zoonotic agent. antibiotics have long been used in the swine industry for disease treatment/prevention and growth promoters. this pattern of utilization resulted in the spread of antibiotic resistance in s. suis worldwide. interestingly, pigs may harbor s. suis in their tonsils without developing diseases, while north american strains belonging to the ...201424973067
streptococcus suis sorption on agricultural soils: role of soil physico-chemical properties.understanding pathogen sorption on natural soil particles is crucial to protect public health from soilborne and waterborne diseases. sorption of pathogen streptococcus suis on 10 agricultural soils was examined, and its correlations with soil physico-chemical properties were also elucidated. s. suis sorption isotherms conformed to the linear equation, with partition coefficients (ks) ranging from 12.7 ml g(-1) to 100.1 ml g(-1). bacteria were observed to sorb on the external surfaces of soil ag ...201524968305
control of competence for dna transformation in streptococcus suis by genetically transferable pherotypes.here we show that s. suis, a major bacterial pathogen of pigs and emerging pathogen in humans responds to a peptide pheromone by developing competence for dna transformation. this species does not fall within any of the phylogenetic clusters of streptococci previously shown to regulate competence via peptide pheromones suggesting that more species of streptococci may be naturally competent. induction of competence was dependent on comx, a sigma factor that controls the streptococcal late compete ...201424968201
impact of antibiotic use in the swine industry.antibiotic resistance in bacteria associated with pigs not only affects pig production but also has an impact on human health through the transfer of resistant organisms and associated genes via the food chain. this can compromise treatment of human infections. in the past most attention was paid to glycopeptide and streptogramin resistance in enterococci, fluoroquinolone resistance in campylobacter and multi-drug resistance in escherichia coli and salmonella. while these are still important the ...201424959754
epidemiology, clinical manifestations, and outcomes of streptococcus suis infection in humans.streptococcus suis, a bacterium that affects pigs, is a neglected pathogen that causes systemic disease in humans. we conducted a systematic review and meta-analysis to summarize global estimates of the epidemiology, clinical characteristics, and outcomes of this zoonosis. we searched main literature databases for all studies through december 2012 using the search term "streptococcus suis." the prevalence of s. suis infection is highest in asia; the primary risk factors are occupational exposure ...201424959701
latest developments on streptococcus suis: an emerging zoonotic pathogen: part 2.first international workshop on streptococcus suis, beijing, china, 12-13 august 2013. this second and final chapter of the report on the first international workshop on streptococcus suis follows on from part 1, published in the april 2014, volume 9, issue 4 of future microbiology. s. suis is a swine pathogen and a zoonotic agent afflicting people in close contact with infected pigs or pork meat. although sporadic cases of human infections had been reported worldwide, deadly s. suis outbreaks e ...201424957086
gluconate 5-dehydrogenase (ga5dh) participates in streptococcus suis cell division.bacterial cell division is strictly regulated in the formation of equal daughter cells. this process is governed by a series of spatial and temporal regulators, and several new factors of interest to the field have recently been identified. here, we report the requirement of gluconate 5-dehydrogenase (ga5dh) in cell division of the zoonotic pathogen streptococcus suis. ga5dh catalyzes the reversible reduction of 5-ketogluconate to d-gluconate and was localized to the site of cell division. the d ...201424916441
characterization of multi-drug tolerant persister cells in streptococcus suis.persister cells constitute a subpopulation of dormant cells within a microbial population which are genetically identical but phenotypically different to regular cells. notably, persister cells show an elevated tolerance to antimicrobial agents. thus, they are considered to represent a microbial 'bet-hedging' strategy and are of particular importance in pathogenic bacteria.201424885389
[clinical situation, diagnosis and prevention of a streptococcus suis serotype 7 problem on a farm].in an austrian piglet producing farm with 1500 sows a high incidence of meningitis, arthritis and sudden death was recorded in five to eight week old piglets. overall losses were 1.8%. streptococcus (s.) suis serotype 7 was detected with an intermediate to high specific bacterial load in all samples taken from brains and joints of 17 untreated piglets with typical clinical signs. all isolates showed an identical spectrum of virulence-associated genes (mrp+, epf-, ofs-, sly-) and expressed a rela ...201424881269
streptococcus suis infection and malignancy in man, spain. 201424856779
antimicrobial susceptibility monitoring of respiratory tract pathogens isolated from diseased cattle and pigs across europe: the vetpath study.vetpath is an ongoing pan-european antibiotic susceptibility monitoring programme collecting pathogens from diseased antimicrobial non-treated cattle, pigs and poultry. in the current study, 1001 isolates from cattle and pig respiratory tract infections were tested for their antimicrobial susceptibilities. non-replicate lung samples or nasopharyngeal/nasal swabs were collected from animals with acute clinical signs in 11 countries during 2002-2006. pasteurella multocida and mannheimia haemolytic ...201424837878
bacterial adhesion of streptococcus suis to host cells and its inhibition by carbohydrate ligands.streptococcus suis is a gram-positive bacterium, which causes sepsis and meningitis in pigs and humans. this review examines the role of known s. suis virulence factors in adhesion and s. suis carbohydrate-based adhesion mechanisms, as well as the inhibition of s. suis adhesion by anti-adhesion compounds in in vitro assays. carbohydrate-binding specificities of s. suis have been identified, and these studies have shown that many strains recognize galα1-4gal-containing oligosaccharides present in ...201324833053
use of tetravalent galabiose for inhibition of streptococcus suis serotype 2 infection in a mouse model.streptococcus suis is an important swine pathogen associated with a variety of infections such as meningitis, arthritis and septicemia. the bacterium is zoonotic and has been found to cause meningitis especially in humans occupationally exposed to infected pigs. since adhesion is a prerequisite for colonization and subsequent infection, anti-adhesion treatment seems a natural alternative to traditional treatment with antibiotics. in order to optimize the inhibitory potency a multivalency approac ...201324832804
overexpression of an abc transporter and mutations of gyra, gyrb, and parc in contributing to high-level ciprofloxacin resistance in streptococcus suis type 2.streptococcus suis is a pathogen of zoonotic diseases. moreover, the emergence of fluoro-quinolones (fqs) resistance in this pathogen has severe consequences for pigs and human health. in this study, the molecular mechanism of fqs resistance in s. suis type 2 (ss2) sensitive strains isolated from pigs was assessed after in vitro induction of resistance against the most frequently used fqs: ciprofloxacin, norfloxacin, and enrofloxacin. proteome analysis, sequencing and real-time rt-pcr results st ...201424815385
effect of tran on virulence through regulating metabolism and stress tolerance of streptococcus suis serotype 2.streptococcus suis (ss) is an important zoonotic pathogen causing a variety of life-threatening infections in pigs and humans. tran, a novel transcriptional regulator which was identified to be an infection-related factor in s. suis serotype 2 using suppression subtractive hybridization (ssh), has been reported by our group. in this study, a tran deletion mutant was constructed to compare with the wild-type zy05719 in some biological characteristics. it is suggested that longer chains and relati ...201424813303
latest developments on streptococcus suis: an emerging zoonotic pathogen: part 1.first international workshop on streptococcus suis, beijing, china, 12-13 august 2013 the first international workshop on streptococcus suis, which is an important swine pathogen and emerging zoonotic agent, took place in beijing, jointly organized by the faculty of veterinary medicine, university of montreal, canada and the national institute for communicable disease control and prevention, china cdc. the aim of the meeting was to gather together, for the first time, more than 80 researchers wo ...201424810343
colloidal gold-based immunochromatographic strip test compromising optimised combinations of anti-s. suis capsular polysaccharide polyclonal antibodies for detection of streptococcus suis.a rapid diagnosis kit that detects streptococcus suis (s. suis) antigens from urine with an immunochromatographic stripe (ics) test was developed in this study. the ics test was produced using colloidal gold coated with polyclonal antibodies (pabs) against s. suis. the pabs were developed from rabbits immunised with s. suis serotype 2 capsular polysaccharides (cps). development of the pabs was investigated to establish their binding to cps and to determine the maximum sensitivity of two combinat ...201424800681
[expression, purification and higg-binding activity identification of truncated streptococcus suis factor h-binding protein].to construct a prokaryotic expression vector of the his-tagged truncated factor h-binding protein (fhb) fragments, fhb-n (amino acids 45-344aa) and fhb-c (amino acids 345-644aa), of streptococcus suis serotype 2, express it in e.coli bl21 (de3) in order to acquire high-purity recombinant protein, and finally identify the binding activity with human serum igg (higg).201424796751
the streptococcus suis transcriptional landscape reveals adaptation mechanisms in pig blood and cerebrospinal fluid.streptococcus suis (ss) is an important pathogen of pigs, and it is also recognized as a zoonotic agent for humans. ss infection may result in septicemia or meningitis in the host. however, little is known about genes that contribute to the virulence process and survival within host blood or cerebrospinal fluid (csf). small rnas (srna) have emerged as key regulators of virulence in several bacteria, but they have not been investigated in ss. here, using a differential rna-sequencing approach and ...201424759092
correlation between pfge groups and mrp/epf/sly genotypes of human streptococcus suis serotype 2 in northern thailand.streptococcus suis infection is a severe zoonotic disease commonly found in northern thailand where people often consume raw pork and/or pig's blood. the most frequent clinical presentations are meningitis, sepsis, and endocarditis with higher rate of mortality and hearing loss sequelae. to clarify the correlation between pulsed-field gel electrophoresis (pfge) groups and mrp/epf/sly genotypes of s. suis serotype 2, 62 patient and 4 healthy pig isolates from northern thailand were studied. by pf ...201424734186
characterisation of streptococcus suis isolates from wild boars (sus scrofa).wild boar are widely distributed throughout the iberian peninsula and can carry potentially virulent strains of streptococcus suis. the objective of this study was to determine the prevalence of s. suis in wild boars from two large geographical regions of spain. serotypes 1, 2, 7 and 9 identified were further genetically characterised by virulence-associated genotyping, pulsed-field gel electrophoresis (pfge) and multilocus sequence typing (mlst) to determine the population structure of s. suis ...201424726078
streptococcus suis-related prosthetic joint infection and streptococcal toxic shock-like syndrome in a pig farmer in the united states.streptococcus suis is an emerging swine-associated zoonotic agent that can cause meningitis and septicemia in humans. we present, to our knowledge, the first case of s. suis arthroplasty infection and streptococcal toxic shock-like syndrome due to an nonencapsulated serotype 5 strain in north america.201424719433
transcriptional approach to study porcine tracheal epithelial cells individually or dually infected with swine influenza virus and streptococcus suis.swine influenza is a highly contagious viral infection in pigs affecting the respiratory tract that can have significant economic impacts. streptococcus suis serotype 2 is one of the most important post-weaning bacterial pathogens in swine causing different infections, including pneumonia. both pathogens are important contributors to the porcine respiratory disease complex. outbreaks of swine influenza virus with a significant level of co-infections due to s. suis have lately been reported. in o ...201424708855
streptococcus suis serotyping by a new multiplex pcr.a multiplex pcr was developed to detect all true serotypes of streptococcus suis. this multiplex pcr was composed of four reaction sets. the first set identified nine serotypes (serotypes 1/2, 1, 2, 3, 7, 9, 11, 14 and 16), the second set identified eight serotypes (serotypes 4, 5, 8, 12, 18, 19, 24 and 25), the third set identified seven serotypes (serotypes 6, 10, 13, 15, 17, 23 and 31), and the last set identified five serotypes (serotypes 21, 27, 28, 29 and 30). this assay correctly detected ...201424696517
antimicrobial susceptibility of streptococcus suis isolated from clinically healthy swine in brazil.streptococcus suis is an important pathogen in the swine industry. this study is the first to report on the antimicrobial susceptibility of s. suis isolated from clinically healthy pigs in brazil; the fourth major pork producer in the world. the antimicrobial susceptibility of 260 strains was determined by disc diffusion method. strains were commonly susceptible to ceftiofur, cephalexin, chloramphenicol, and florfenicol, with more than 80% of the strains being susceptible to these antimicrobials ...201424688177
antimicrobial susceptibility of escherichia coli f4, pasteurella multocida, and streptococcus suis isolates from a diagnostic veterinary laboratory and recommendations for a surveillance system.antimicrobial susceptibility data on escherichia coli f4, pasteurella multocida, and streptococcus suis isolates from ontario swine (january 1998 to october 2010) were acquired from a comprehensive diagnostic veterinary laboratory in ontario, canada. in relation to the possible development of a surveillance system for antimicrobial resistance, data were assessed for ease of management, completeness, consistency, and applicability for temporal and spatial statistical analyses. limited farm locati ...201424688133
role of capsule and suilysin in mucosal infection of complement-deficient mice with streptococcus suis.virulent streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. one objective of this study was to elucidate the function of complement in innate immune defense against s. suis. experimental infection of wild-type (wt) and c3(-/-) mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal s. suis infection. s. suis wt but not an unencapsulated mutant caused mortality asso ...201424686060
functional analysis of c-di-amp phosphodiesterase, gdpp, in streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is an important zoonotic pathogen that causes serious diseases in pigs and humans. gdpp protein is a recently discovered specific phosphodiesterase that degrades cyclic diadenosine monophosphate (c-di-amp). it is widely distributed among the firmicutes phylum and altered expression of gdpp is associated with several phenotypes in various bacterial strains. we investigated the role of gdpp in physiology and virulence in ss2. an in-frame mutant of gdpp was const ...201424680501
the ccpa regulon of streptococcus suis reveals novel insights into the regulation of the streptococcal central carbon metabolism by binding of ccpa to two distinct binding motifs.streptococcus suis (s. suis) is a neglected zoonotic streptococcus causing fatal diseases in humans and in pigs. the transcriptional regulator ccpa (catabolite control protein a) is involved in the metabolic adaptation to different carbohydrate sources and virulence of s. suis and other pathogenic streptococci. in this study, we determined the dna binding characteristics of ccpa and identified the ccpa regulon during growth of s. suis. electrophoretic mobility shift analyses showed promiscuous d ...201424673665
streptococcus suis type 2 ssu0587 protein is a beta-galactosidase that contributes to bacterial adhesion but not to virulence in mice.bacterial surface proteins play key roles in virulence and often contribute to bacterial adhesion and invasion. we discovered that the streptococcus suis type 2 (ss2) gene ssu0587 encodes a protein of 1,491 amino acids that possesses β-galactosidase activity. the surface association of the protein was dependent upon sortase activity. deleting ssu0587 from clinical ss2 isolate jx081101 caused a loss of both β-galactosidase activity and adherence to microvascular endothelial cells. deleting ssu058 ...201424670993
streptococcus suis infection: an emerging/reemerging challenge of bacterial infectious diseases?streptococcus suis (s. suis) is a family of pathogenic gram-positive bacterial strains that represents a primary health problem in the swine industry worldwide. s. suis is also an emerging zoonotic pathogen that causes severe human infections clinically featuring with varied diseases/syndromes (such as meningitis, septicemia, and arthritis). over the past few decades, continued efforts have made significant progress toward better understanding this zoonotic infectious entity, contributing in par ...201424667807
a functional peptidoglycan hydrolase characterized from t4ss in 89k pathogenicity island of epidemic streptococcus suis serotype 2.streptococcus suis serotype 2 (s. suis 2) has evolved efficient mechanisms to cause streptococcal toxic shock syndrome (stss), which is a new emerging infectious disease linked to s. suis. we have previously reported that a type iv secretion system (t4ss) harbored by the specific 89k pathogenicity island (pai) of s. suis 2 contributes to the development of stss and mediates horizontal transfer of 89k. however, the 89k t4ss machinery assembly in vivo and in vitro is poorly understood, and the com ...201424655418
capsule loss or death: the position of mutations among capsule genes sways the destiny of streptococcus suis.streptococcus suis, an emerging zoonotic pathogen, is responsible for various diseases in swine and humans. most s. suis strains from clinical cases possess a group of capsular polysaccharide synthesis (cps) genes and phenotypically express capsular polysaccharides (cps). although cps are considered to be an important virulence factor, our previous study showed that many s. suis isolates from porcine endocarditis lost their cps, and some of these unencapsulated isolates had large insertions or d ...201424654559
carbohydrate availability regulates virulence gene expression in streptococcus suis.streptococcus suis is a major bacterial pathogen of young pigs causing worldwide economic problems for the pig industry. s. suis is also an emerging pathogen of humans. colonization of porcine oropharynx by s. suis is considered to be a high risk factor for invasive disease. in the oropharyngeal cavity, where glucose is rapidly absorbed but dietary α-glucans persist, there is a profound effect of carbohydrate availability on the expression of virulence genes. nineteen predicted or confirmed s. s ...201424642967
contribution of eukaryotic-type serine/threonine kinase to stress response and virulence of streptococcus suis.streptococcus suis serotype 2 (ss2) is an important swine and human pathogen responsible for septicemia and meningitis. the bacterial homologues of eukaryotic-type serine/threonine kinases (estks) have been reported to play critical roles in various cellular processes. to investigate the role of stk in ss2, an isogenic stk mutant strain (δstk) and a complemented strain (cδstk) were constructed. the δstk showed a significant decrease in adherence to hep-2 cells, compared with the wild-type strain ...201424637959
detection of streptococcus suis in bioaerosols of swine confinement buildings.streptococcus suis is an important swine pathogen that can cause septicemia, meningitis, and pneumonia. also recognized as an emerging zoonotic agent, it is responsible for outbreaks of human infections in asian countries. serotype 2 is the predominant isolate from diseased animals and humans. the aerosolization of s. suis in the air of swine confinement buildings (scb) was studied. the presence of s. suis in bioaerosols was monitored in scb where cases of infection had been reported and in heal ...201424632262
virulence genes and genetic diversity of streptococcus suis serotype 2 isolates from thailand.isolates of streptococcus suis from different western countries as well as those from china and vietnam have been previously well characterized. so far, the genetic characteristics and relationship between s. suis strains isolated from both humans and pigs in thailand are unknown. in this study, a total of 245 s. suis isolates were collected from both human cases (epidemic and sporadic) and pigs (diseased and asymptomatic) in thailand. bacterial strains were identified by biochemical tests and p ...201324589104
development of a two-step multiplex pcr assay for typing of capsular polysaccharide synthesis gene clusters of streptococcus suis.we developed a practical and easy two-step multiplex pcr assay to aid in serotyping of streptococcus suis. the assay accurately typed almost all of the serotype reference strains and field isolates of various serotypes and also identified the genotypes of capsular polysaccharide synthesis gene clusters of some serologically nontypeable strains.201424574288
atypical streptococcus suis in man, argentina, 2013. 201424565286
septic arthritis caused by streptococcus suis serotype 5 in pig farmer. 201424565084
the β-galactosidase (bgac) of the zoonotic pathogen streptococcus suis is a surface protein without the involvement of bacterial virulence.streptococcal pathogens have evolved to express exoglycosidases, one of which is bgac β-galactosidase, to deglycosidate host surface glycolconjucates with exposure of the polysaccharide receptor for bacterial adherence. the paradigm bgac protein is the bgac product of streptococcus, a bacterial surface-exposed β-galactosidase. here we report the functional definition of the bgac homologue from an epidemic chinese strain 05zyh33 of the zoonotic pathogen streptococcus suis. bioinformatics analyses ...201424556915
synthesis of multi-fullerenes encapsulated palladium nanocage, and its application in electrochemiluminescence immunosensors for the detection of streptococcus suis serotype 2.a novel functionalized material is synthesized using surface-decorated fullerene (c60) to encapsulate hollow and porous palladium nanocages (pdncs), and is applied to fabricate an electrochemiluminescence (ecl) immunosensor for the detection of streptococcus suis serotype 2 (ss2). pdncs with hollow interiors and porous walls are prepared using a galvanic replacement reaction between silver nanocubes and metal precursor salts. then, c60 reacts with l-cysteine (l-cys) to form l-cys functionalized ...201424554632
deregulated balance of omega-6 and omega-3 polyunsaturated fatty acids following infection by the zoonotic pathogen streptococcus suis.streptococcus suis is an important swine pathogen and an emergent zoonotic pathogen. excessive inflammation caused by s. suis is responsible for early high mortality in septic shock-like syndrome cases. polyunsaturated fatty acids (pufas) may contribute to regulating inflammatory processes. this study shows that mouse infection by s. suis is accompanied by an increase of arachidonic acid, a proinflammatory omega-6 (ω-6) pufa, and by a decrease of docosahexaenoic acid, an anti-inflammatory ω-3 pu ...201424549326
the protective protein sao (surface antigen one) is not a critical virulence factor for streptococcus suis serotype 2.surface antigen one (sao) is protein that was shown to protect pigs in vaccination trials against disease caused by streptococcus suis. here, we used an isogenic δsao mutant to investigate the insofar unknown role of sao in s. suis virulence. the δsao mutant and its wild-type parent strain (sequence type 1, european strain) did not present significant differences on levels of adhesion/invasion of swine respiratory epithelial cells. moreover, the δsao mutant resisted phagocytosis by macrophages s ...201424530923
high-level expression, purification and characterisation of porcine β-defensin 2 in pichia pastoris and its potential as a cost-efficient growth promoter in porcine feed.porcine β-defensin 2 (pbd2), a recently discovered porcine defensin that is produced by the intestine, exerts antimicrobial activities and innate immune effects that are linked to intestinal diseases in pigs. here, we report a codon-optimised protein corresponding to mature pbd2 cdna that was expressed and purified in pichia pastoris yeast. the highest amount of secreted protein (3,694.0 mg/l) was reached 144 h into a 150-h induction during high-density cultivation. precipitation followed by gel ...201424515729
comparative genomic hybridization identifies virulence differences in streptococcus suis.streptococcus suis is an important zoonotic pathogen. however, identification of virulent s. suis strains is complicated because of the high diversity of the species. here we evaluated the genetic difference among s. suis strains using comparative genomic hybridization (cgh) and virulence variation in vivo and in vitro. we showed that different clades differed in their ability to activate tlr2/6 in vitro and their capacity to induce cytokine production in vivo as well as their resistance to phag ...201424503649
adhesion of bacterial pathogens to soil colloidal particles: influences of cell type, natural organic matter, and solution chemistry.bacterial adhesion to granular soil particles is well studied; however, pathogen interactions with naturally occurring colloidal particles (<2 μm) in soil has not been investigated. this study was developed to identify the interaction mechanisms between model bacterial pathogens and soil colloids as a function of cell type, natural organic matter (nom), and solution chemistry. specifically, batch adhesion experiments were conducted using nom-present, nom-stripped soil colloids, streptococcus sui ...201424495985
characterization and proteome analysis of inosine 5-monophosphate dehydrogenase in epidemic streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is an important zoonotic pathogen that causes severe disease symptoms in pigs and humans. in the present study, we found one isogenic mutant lacking inosine 5-monophosphate dehydrogenase (impdh) δzy05719 was attenuated in pigs compared with the wild-type ss2 strain zy05719. comparative proteome analysis of the secreted proteins expression profiles between zy05719 and δzy05719 allowed us to identify triosephosphate isomerase (tpi) and glyceraldehyde phosphate d ...201424458764
streptococcus suis adenosine synthase functions as an effector in evasion of pmn-mediated innate immunit.streptococcus suis serotype 2 (s. suis 2) is a highly invasive pathogen in pigs and humans that can cause severe systemic infection. sepsis and meningitis are the most common clinical manifestations of s. suis 2 infection. however, the mechanisms of s. suis 2 surviving in human blood remains unclear, so to identify novel virulence factors in evasion of polymorphonuclear leukocyte (pmn)-mediated innate immunity play important roles in developing therapies against s. suis 2 infection. here, we fou ...201424446521
microbiological identification and analysis of swine lungs collected from carcasses in swine farms, china.the primary objective of this 3 years study was to determine the prevalence of porcine pathogens of the lungs of swine in swine farms in southern china. a total of 5,420 samples were collected from 200 swine farms. the bacterium that was most commonly isolated was streptococcus suis, with 10.24 % of the samples being positive, 114 lungs (2.1 %) were positive for pseudorabies virus and 263 (4.85 %) were positive for classical swine fever virus; much lower than positive for prrsv (15.1 %, p = 0.02 ...201324426158
[analysis of pathogen spectrum of encephalitis/meningitis in northwestern area of china].to learn the characteristics of pathogen spectrum of encephalitis /meningitis in northwestern area of china.201324378133
biofilm formation, host-cell adherence, and virulence genes regulation of streptococcus suis in response to autoinducer-2 signaling.autoinducer-2 (ai-2) is a universal signal molecule mediating intra- and interspecies communication among bacteria. ai-2 is a byproduct of the luxs enzyme during the catabolism of s-adenosylhomocysteine and plays critical roles in regulating various behaviors of bacteria. in our previous study, the function of luxs in ai-2 production was verified in streptococcus suis (ss). decreased levels of ss biofilm formation and host-cell adherence as well as the inability to produce ai-2 were observed in ...201424370626
identification of the novel lincosamide resistance gene lnu(e) truncated by isenfa5-cfr-isenfa5 insertion in streptococcus suis: de novo synthesis and confirmation of functional activity in staphylococcus aureus.the novel lincosamide resistance gene lnu(e), truncated by insertion of an isenfa5-cfr-isenfa5 segment, was identified in streptococcus suis. the gene lnu(e) encodes a 173-amino-acid protein with ≤69.4% identity to other lincosamide nucleotidyltransferases. the lnu(e) gene and its promoter region were de novo synthesized, and staphylococcus aureus rn4220 carrying a shuttle vector with the cloned lnu(e) gene showed a 16-fold increase in the lincomycin mic. mass spectrometry experiments demonstrat ...201424366733
the two-component system nisk/nisr contributes to the virulence of streptococcus suis serotype 2.two-component signal-transduction systems (tcstss) may regulate some virulence factors in response to external stimuli, and thus allowing streptococcus suis serotype 2 to interact with the host, promote survival, and cause disease. here, a mutant of the niskr tcsts had attenuated virulence in vitro, as exemplified by lowered hemolytic activity, reduced adherence to epithelial cells, increased elimination by macrophages, and decreased resistance to killing by neutrophils. results also showed that ...201424342108
overexpression of luxs cannot increase autoinducer-2 production, only affect the growth and biofilm formation in streptococcus suis.luxs/ai-2 quorum sensing (qs) system involves the production of cell signaling molecules via luxs-based autoinducer-2 (ai-2). luxs has been reported to plays critical roles in regulating various behaviors of bacteria. ai-2 is a byproduct of the catabolism of s-adenosylhomocysteine (sah) performed by the luxs and pfs enzymes. in our previous study, the function of luxs in ai-2 production was verified in streptococcus suis (ss). decreased levels of ss biofilm formation and host-cell adherence as w ...201324324385
comparative genomic analysis shows that streptococcus suis meningitis isolate sc070731 contains a unique 105k genomic island.streptococcus suis (ss) is an important swine pathogen worldwide that occasionally causes serious infections in humans. ss infection may result in meningitis in pigs and humans. the pathogenic mechanisms of ss are poorly understood. here, we provide the complete genome sequence of s. suis serotype 2 (ss2) strain sc070731 isolated from a pig with meningitis. the chromosome is 2,138,568bp in length. there are 1933 predicted protein coding sequences and 96.7% (57/59) of the known virulence-associat ...201424316490
[streptococcus suis acute meningitis]. 201424314816
multiple-class antimicrobial resistance surveillance in swine escherichia coli f4, pasteurella multocida and streptococcus suis isolates from ontario and the impact of the 2004-2006 porcine circovirus type-2 associated disease outbreak.the objective of this work was to describe trends in multiple-class antimicrobial resistance present in clinical isolates of escherichia coli f4, pasteurella multocida and streptococcus suis from ontario swine 1998-2010. temporal changes in multiple-class resistance varied by the pathogens examined; significant yearly changes were apparent for the e. coli and p. multocida data. although not present in the e. coli data, significant increases in multiple-class resistance within p. multocida isolat ...201424309129
the contribution of suilysin to the pathogenesis of streptococcus suis meningitis.streptococcus suis is an emerging zoonotic pathogen, and causes sepsis and meningitis in humans. although sequence type (st) 1 and st104 strains are capable of causing sepsis, st1 strains commonly cause meningitis. in this study, we investigated the role of suilysin, a member of cholesterol-dependent cytolysins, in differential pathogenicity between st1 and st104 strains.201424285845
restoration of bioactive lantibiotic suicin from a remnant lan locus of pathogenic streptococcus suis serotype 2.lantibiotics are ribosomally synthesized, posttranslationally modified antimicrobial peptides. their biosynthesis genes are usually organized in gene clusters, which are mainly found in gram-positive bacteria, including pathogenic streptococci. three highly virulent streptococcus suis serotype 2 strains (98hah33, 05zyh33, and sc84) have been shown to contain an 89k pathogenicity island. here, on these islands, we unveiled and reannotated a putative lantibiotic locus designated sui which contains ...201424271178
[streptococcus suis meningitis in pig farmers: report of first two cases in chile].human infection by streptococcus suis is a zoonosis with a known occupational risk. meningitis is its most frequent clinical manifestation. we present the first two cases in chile.201324248173
[first case of meningitis by streptococcus suis in the norwest area of argentina].streptococcus suis causes meningitis, bacteremia, endocarditis, endophthalmitis, artrithis and toxic shock in both pigs and human beings. the incidence of this pathogen is increasing worldwide. a case of 54 years old men from a rural zone of tucumán, argentina with two days of headache, vomit and photophobia was admitted septic, with purulent meningitis. streptococcus suis was growth from the blood and cerebrospinal fluid culture. the patient was treated with ceftriaxona and had a good evolution ...201324248172
[laboratory confirmation of streptococcus suis in chile]. 201324248169
streptococcus suis dnase ssna contributes to degradation of neutrophil extracellular traps (nets) and evasion of net-mediated antimicrobial activity.streptococcus suis is an important cause of different pathologies in pigs and humans, most importantly fibrinosuppurative meningitis. tissue infected with this pathogen is substantially infiltrated with neutrophils, but the function of neutrophil extracellular traps (nets) - a more recently discovered antimicrobial strategy of neutrophils - in host defence against strep. suis has not been investigated. the objective of this work was to investigate the interaction of strep. suis with nets in vitr ...201424222615
whole-genome sequence of streptococcus suis serotype 3 strain yb51.we report here the second complete genome sequence of streptococcus suis serotype 3 (strain yb51). the genome is 2,043,655 bp in length, which is 14,840 bp longer than the first reported genome of the same serotype, and it covers 2,012 coding sequences, 56 trnas, and 4 rrna loci.201324179118
prevalent distribution and conservation of streptococcus suis lmb protein and its protective capacity against the chinese highly virulent strain infection.streptococcus suis (s. suis) is an important zoonotic pathogen that causes multiple diseases in both pigs and humans. many studies suggest that streptococcus utilizes host extracellular matrix proteins, including laminin, for adhesion and invasion of host cells. recently, we identified a putative lmb protein (cds 0330) of a highly virulent strain of s. suis (serotype 2). in this study, we characterized the ability of cds 0330 to bind human laminin, and evaluated the protective efficacy of a reco ...201424120016
[bilateral sensorineural hearing impairment due to streptococcus suis meningitis 20 days after swine bite].streptococcus suis (s. suis) is a zoonotic pathogen in pigs, which can be transmitted to humans by close contact. meningitis is the most common clinical manifestations of s. suis infection and hearing impairment is a frequent complication. the risk of s. suis meningitis is higher in people who work in the swine industry. the patient was a 53-year-old woman working in the swine industry, who developed headache and fever 20 days after a swine bite. she was diagnosed as meningitis and s. suis was d ...201324097324
antimicrobial activity of nisin against the swine pathogen streptococcus suis and its synergistic interaction with antibiotics.streptococcus suis serotype 2 is known to cause severe infections in pigs, including meningitis, endocarditis and pneumonia. furthermore, this bacterium is considered an emerging zoonotic agent. recently, increased antibiotic resistance in s. suis has been reported worldwide. the objective of this study was to evaluate the potential of nisin, a bacteriocin of the lantibiotic class, as an antibacterial agent against the pathogen s. suis serotype 2. in addition, the synergistic activity of nisin i ...201324096107
subcytolytic effects of suilysin on interaction of streptococcus suis with epithelial cells.suilysin is a pore-forming cholesterol-dependent cytolysin secreted by streptococcus suis (s. suis), an important swine and zoonotic pathogen. the role of suilysin in s. suis host-cell interaction is still unclear. we found a higher adherence and invasion rate of an unencapsulated sly-positive strain in comparison to its isogenic sly-negative mutant. electron microscopy revealed that formation of membrane ruffles accompanying invasion of the sly-positive strain was abolished in the sly-negative ...201324095145
capsular sialic acid of streptococcus suis serotype 2 binds to swine influenza virus and enhances bacterial interactions with virus-infected tracheal epithelial cells.streptococcus suis serotype 2 is an important swine bacterial pathogen, and it is also an emerging zoonotic agent. it is unknown how s. suis virulent strains, which are usually found in low quantities in pig tonsils, manage to cross the first host defense lines to initiate systemic disease. influenza virus produces a contagious infection in pigs which is frequently complicated by bacterial coinfections, leading to significant economic impacts. in this study, the effect of a preceding swine influ ...201324082069
identification and characterization of a novel hemolysis-related gene in streptococcus suis serotype 2.streptococcussuis serotype 2 (ss 2) is an important zoonotic pathogen that has caused two major infectious outbreaks of streptococcal toxic shock syndrome (stss) in china. a novel gene located in the 89k pathogenicity island (pai) encoding a putative hemolysin-iii-related protein (hhly3) has been previously characterized. in this study, the ss2 deletion mutant of the exogenous gene hhly3 was constructed by homologous recombination. this protein was found to exhibit cytolytic activity, and hemoly ...201324069329
alcohol consumption promotes the intestinal translocation of streptococcus suis infections.streptococcus suis is an emerging zoonotic agent. this study aimed to investigate whether s. suis is likely to translocate across the intestines of human hosts who have liver disease and/or consume alcohol. both the alcoholism and cirrhosis models exhibited high mrna expression of tgf and collagen1, but only the cirrhosis model had fibrosis in the liver. after both models were infected with s. suis, significantly different concentrations of s. suis were detected in the blood and brains of the al ...201324036179
in vitro biofilm forming potential of streptococcus suis isolated from human and swine in china.streptococcus suis is a swine pathogen and also a zoonotic agent. the formation of biofilms allows s. suis to become persistent colonizers and resist clearance by the host immune system and antibiotics. in this study, biofilm forming potentials of various s. suis strains were characterized by confocal laser scanning microscopy (clsm), scanning electron microscopy (sem) and tissue culture plates stained with crystal violet. in addition, the effects of five antimicrobial agents on biofilm formatio ...201224031918
postantibiotic effects and postantibiotic sub-mic effects of tilmicosin, erythromycin and tiamulin on erythromycin-resistant streptococcus suis.the postantibiotic effects (paes) and postantibiotic sub-mic effects (pa smes) of tilmicosin, erythromycin and tiamulin on erythromycin-susceptible and erythromycin-resistant strains of streptococcus suis (m phenotype) were investigated in vitro. tilmicosin and tiamulin induced significantly longer pae and pa sme against both erythromycin-susceptible and erythromycin-resistant strains than did erythromycin. the durations of pae and pa smes were proportional to the concentrations of drugs used fo ...200924031450
digoxigenin-labeled in situ hybridization for the detection of streptococcus suis dna in polyserositis and a comparison with biotinylated in situ hybridization.the objective of this study was to develop digoxigenin-labeled in situ hybridization (ish) for the detection of streptococcus suis in naturally infected pigs with polyserositis and to compare it with biotinylated ish. digoxigenin-labeled hybridization signals for s. suis were observed in cells that had infiltrated the fibrous polyserositis and microcolonies in the blood vessels. mock hybridization showed no hybridization signals for endogenous digoxigenin. biotinylated hybridization signals for ...201423985415
streptococcus suis meningitis and bacteremia in man, french guiana. 201323977863
development of multiplex pcr assays for the identification of the 33 serotypes of streptococcus suis.streptococcussuis is an important zoonotic agent causing severe diseases in pigs and humans. to date, 33 serotypes of s. suis have been identified based on antigenic differences in the capsular polysaccharide. the capsular polysaccharide synthesis (cps) locus encodes proteins/enzymes that are responsible for capsular production and variation in the capsule structures are the basis of s. suis serotyping. multiplex and/or simplex pcr assays have been developed for 15 serotypes based on serotype-sp ...201323951285
effect of licochalcone a on growth and properties of streptococcus suis.streptococcus suis (s.suis) is an important emerging worldwide pig pathogen and zoonotic agent with rapid evolution of virulence and drug resistance. in this study, we wanted to investigate the effect of licochalcone a on growth and properties of streptococcus suis. the antimicrobial activity of licochalcone a was tested by growth inhibition assay and the minimal inhibitory concentrations (mics) also were determined. the effect of licochalcone a on s.suis biofilm formation was characterized by c ...201323935843
development of a lamp assay for rapid detection of different intimin variants of attaching and effacing microbial pathogens.intimin harboured by pathogenic escherichia coli (e. coli) strains is a key virulence factor involved in host cell adherence and colonization. twenty-seven intimin-encoding e. coli attaching and effacing (eae) gene variants have been reported according to their 3' binding domain sequences. in our study, we developed a specific and sensitive loop-mediated isothermal amplification (lamp) assay to detect all known intimin variants. four primers specific for six regions of eae genes were designed us ...201323893919
rapid visual detection of highly pathogenic streptococcus suis serotype 2 isolates by use of loop-mediated isothermal amplification.streptococcus suis serotype 2 (s. suis 2) is an important zoonotic pathogen that causes considerable economic losses to the pig industry and significantly threatens public health worldwide. the highly pathogenic s. suis 2, which contains the 89k pathogenicity island (pai), has caused large-scale outbreaks of infections in humans, resulting in high mortality rates. in this study, we established two loop-mediated isothermal amplification (lamp)-based assays that can rapidly detect s. suis 2 and th ...201323884995
characterization of streptococcus suis serotype 2 isolates from china.streptococcus suis (s. suis) is a major pathogen in the pig industry and an important zoonotic agent that causes severe invasive diseases in humans. previous studies based on multilocus sequence typing (mlst) and the associations between sequence types and genotypes or virulence suggested that north american s. suis serotype 2 isolates are composed of multiple populations. this study investigated the population structure of s. suis serotype 2 isolates in china. we constructed a phylogenetic tree ...201323876933
the genetically modified suilysin, rsly(p353l), provides a candidate vaccine that suppresses proinflammatory response and reduces fatality following infection with streptococcus suis.streptococcus suis is a persistent global hazard in the swine industry and an emerging threat to public health. the high mortality in china following outbreaks of streptococcal toxic shock syndrome (stss) underscores the urgency for effective prevention. a limited understanding of the pathogenesis of s. suis in stss may explain the lack of biological products for prevention. suilysin (sly) is an important virulence factor in the pathogenesis of s. suis. to identify a candidate vaccine for s. sui ...201323856333
complete genome sequence of streptococcus suis serotype 16 strain tl13.we report here the first complete genome sequence of streptococcus suis serotype 16, which has been identified to be zoonotic. the sequenced strain tl13 was isolated from a pig in china. the genome is 2,038,146 bp in length, covering 1,950 coding sequences, 53 trnas, and 4 rrna loci.201323814033
group b streptococcus and streptococcus suis capsular polysaccharides induce chemokine production by dendritic cells via toll-like receptor 2- and myd88-dependent and -independent pathways.streptococcus agalactiae (also known as group b streptococcus [gbs]) and streptococcus suis are encapsulated streptococci causing severe septicemia and meningitis. bacterial capsular polysaccharides (cpss) are poorly immunogenic, but anti-cps antibodies are essential to the host defense against encapsulated bacteria. the mechanisms underlying anti-cps antibody responses are not fully elucidated, but the biochemistry of cpss, particularly the presence of sialic acid, may have an immunosuppressive ...201323774593
Refresh
firstprev
12345678910...
nextlast
Displaying items 301 - 400 of 1416