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antibiotic susceptibility of bacteria isolated from respiratory tract of pigs in poland between 2004 and 2008.antibiotic susceptibility of bacteria isolated from nasal swabs and lungs of pigs, to 16 commonly used antibiotics, was determined by disc diffusion test. beta-lactams showed the best activity against streptococcus suis (s. suis) (> 99% of susceptible strains). the lowest sensitivity of s. suis was evidenced to: tylosin, tetracycline and neomycin (50%, 40% and 25%, respectively). isolates of escherichia coli (e. coli) demonstrated the highest susceptibility to cephalosporin (85% strains), gentam ...201021077428
structural and thermodynamic characterization of metal ion binding in streptococcus suis dpr.the use of protein cages for the creation of novel inorganic nanomaterials has attracted considerable attention in recent years. ferritins are among the most commonly used protein cages in nanoscience. accordingly, the binding of various metals to ferritins has been studied extensively. dps (dna-binding protein from starved cells)-like proteins belong to the ferritin superfamily. in contrast to ferritins, dps-like proteins form 12-mers instead of 24-mers, have a different ferroxidase center, and ...201021056572
iga1 protease contributes to the virulence of streptococcus suis.streptococcus suis (s. suis) is a major swine pathogen and emerging zoonotic agent. however, the current understanding of the s. suis pathogenesis of infection remains limited. in the present study, the contribution to the pathogenesis of s. suis was evaluated on iga1 protease (or iga gene), which has been regarded as a virulence factor of gram-negative pathogenic bacteria and of certain gram-positive pathogenic bacteria. in contrast to the wild type (wt) strain of s. suis serotype 2, the isogen ...201021041043
purification and characterization of the subtilisin-like protease of streptococcus suis that contributes to its virulence.streptococcus suis is a major swine pathogen that is responsible for severe infections such as meningitis, endocarditis, and septicemia. s. suis is also recognized as a zoonotic agent and expresses several virulence factors. the recently identified subtilisin-like protease (sspa) of s. suis plays an important role in the pathogenicity of this bacterium in animal models. the objective of the present study was to clone, purify, and characterize the sspa of serotype 2 s. suis p1/7. the ssu0757 gene ...201021030165
argr is an essential local transcriptional regulator of the arcabc operon in streptococcus suis and is crucial for biological fitness in an acidic environment.streptococcus suis is one of the most important pathogens in pigs and can also cause severe infections in humans. despite its clinical relevance, very little is known about the factors that contribute to its virulence. recently, we identified a new putative virulence factor in s. suis, the arginine deiminase system (ads), an arginine catabolic enzyme system encoded by the arcabc operon, which enables s. suis to survive in an acidic environment. in this study, we focused on argr, an ads-associate ...201020947575
response of swine spleen to streptococcus suis infection revealed by transcription analysis.streptococcus suis serotype 2 (ss2), a major swine pathogen and an emerging zoonotic agent, has greatly challenged global public health. systematical information about host immune response to the infection is important for understanding the molecular mechanism of diseases.201020937098
bactericidal activity of porcine neutrophil secretions.antimicrobial proteins in neutrophil granules exert their bactericidal activity both within the neutrophil phagolysosome and as components of neutrophil extracellular traps. this study evaluated the bactericidal activity of porcine neutrophil secretions against four bacterial pathogens of swine. porcine neutrophils were treated with or without phorbol myristate acetate (pma), then the resulting supernatants were incubated with escherichia coli k-12, streptococcus suis, actinobacillus suis, or pa ...201020932586
isolation of streptococcus suis from the urine of a clinically ill dog. 201020885835
in vitro characterization of the microglial inflammatory response to streptococcus suis, an important emerging zoonotic agent of meningitis.streptococcus suis is an important swine and human pathogen responsible for septicemia and meningitis. in vivo research in mice suggested that in the brain, microglia might be involved in activating the inflammatory response against s. suis. the aim of this study was to better understand the interactions between s. suis and microglia. murine microglial cells were infected with a virulent wild-type strain of s. suis. two isogenic mutants deficient at either capsular polysaccharide (cps) or hemoly ...201020876287
characterization of streptococcus suis serotype 2 blood infections using rt-qpcr to quantify glutamate dehydrogenase copy numbers.this study characterized the dynamic distribution of bacteria in the blood of pigs infected with streptococcus suis serotype 2 using specific primers and a taqman probe designed to amplify the highly conserved s. suis serotype 2 glutamate dehydrogenase (gdh) gene sequences. gene copy numbers were used to determine the concentration of bacteria in the blood of infected pigs over time using established taqman real-time quantitative pcr methodologies (rt-qpcr). the results showed that the detection ...201020869401
the two-component regulatory system ciarh contributes to the virulence of streptococcus suis 2.two-component regulatory systems (tcss) are widely distributed among bacteria and enable the organisms to make coordinated changes in gene expression in response to a variety of environmental stimuli. in this work, we constructed a mutant strain of the tcs ciarh and measured its virulence in vitro and in vivo. compared with the wild type strain, the mutant strain exhibited a significant decrease in adherence to epithelial cells hep-2 and piec. furthermore, the deletion of ciarh not only enhanced ...201120832201
comparative proteomic analyses of streptococcus suis serotype 2 cell wall-associated proteins.streptococcus suis serotype 2 (ss2) is a zoonotic pathogen that is distributed throughout the world. virulence factors and/or markers of the virulent serotype 2 strains have not been fully identified. in this study a simple, rapid, and non-destructive method was used to extract cell wall-associated proteins from ss2 strains. two virulent strains were compared with one avirulent strain by 2-dimensional electrophoresis (2de). when the results of the 2de analyses were combined with the results of m ...201120824277
microarray analysis of temperature-induced transcriptome of streptococcus suis serotype 2.streptococcus suis serotype 2 (s. suis s2) is able to cause human infections ranging from superficial wounded skin infections to severe invasive infections such as meningitis and streptococcal toxic shock-like syndrome. during its infection cycle, s. suis s2 must acclimatize itself to temperature shift. herein, a whole-genome dna microarray was used to investigate the global transcriptional regulation of an invasive strain of s. suis s2 grown to late-exponential phase at 29°c or 40°c relative to ...201120795872
immunogenicity of an autogenous streptococcus suis bacterin in preparturient sows and their piglets in relation to protection after weaning.streptococcus suis is an important porcine pathogen causing meningitis and other invasive diseases in piglets of different ages. application of s. suis serotype 2 bacterins to specific-pathogen-free (spf) weaning piglets has been demonstrated to protect against the homologous serotype. however, autogenous s. suis bacterins are also applied to sows and suckling piglets in the field. therefore, comparative evaluation of different bacterin immunization regimes, including sow vaccination, was perfor ...201020739502
cell surface characteristics of nontypeable isolates of streptococcus suis.streptococcus suis is a worldwide cause of various swine infections and is also an important agent of zoonosis. strains of s. suis are classified according to their serotype, and currently, 35 serotypes are recognized. the aim of this study was to characterize nontypeable isolates of s. suis with regard to their cell surface properties and compare them with serotype 2 strains, the most frequently associated with infections. the seven nontypeable strains of s. suis isolated from infected animals ...201020738400
identification of the tet(b) resistance gene in streptococcus suis.the tetracycline resistance gene, tet(b), has been described previously in gram negative bacteria. in this study tet(b) was detected in plasmid extracts from 17/111 (15%) streptococcus suis isolates from diseased pigs, representing the first report of this resistance gene in gram positive bacteria.201020696603
longitudinal study of respiratory infection patterns of breeding sows in five farrow-to-finish herds.a longitudinal study was carried out in five french farrow-to-finish herds differently affected by respiratory diseases to describe the carrying and infection patterns of batches of sows to various respiratory pathogens during gestation and lactation. an entire batch of sows was followed during two successive reproduction cycles. nasal, tonsillar and oro-pharyngeal swabs and blood samples were taken from each sow 9 and 4 weeks before farrowing and 1 and 4 weeks after farrowing. mycoplasma hyopne ...201120696539
secondary infection with streptococcus suis serotype 7 increases the virulence of highly pathogenic porcine reproductive and respiratory syndrome virus in pigs.porcine reproductive and respiratory syndrome virus (prrsv) and streptococcus suis are common pathogens in pigs. in samples collected during the porcine high fever syndrome (phfs) outbreak in many parts of china, prrsv and s. suis serotype 7 (ss7) have always been isolated together. to determine whether prrsv-ss7 coinfection was the cause of the phfs outbreak, we evaluated the pathogenicity of prrsv and/or ss7 in a pig model of single and mixed infection.201020696031
cloning, expression, purification, crystallization and preliminary x-ray diffraction analysis of saicar synthase from streptococcus suis serotype 2.phosphoribosylaminoimidazole-succinocarboxamide synthase (saicar synthase) plays an essential role in the de novo biosynthesis of purine nucleotides. in this study, the saicar synthase from streptococcus suis was cloned and overexpressed in escherichia coli. the subsequent product was purified and crystallized using the hanging-drop vapour-diffusion method. the crystals diffracted to 2.8 a resolution and belonged to space group p2, with unit-cell parameters a=70.2, b=52.2, c=153.9 a, beta=102.8 ...201020693665
streptococcus porcorum sp. nov., isolated from domestic and wild pigs.seven isolates of an unidentified gram-positive, catalase-negative coccus-shaped organism isolated from domestic and wild pigs, were characterized by phenotypic and molecular genetic methods. based on cellular morphology and biochemical criteria the isolates were tentatively assigned to the genus streptococcus, although the organisms did not appear to correspond to any recognised species. comparative 16s rrna gene sequencing showed that the unknown bacterium was phylogenetically closely related ...201020675439
microbial communities in the tonsils of healthy pigs.the tonsils of mammals such as humans and pigs are colonized with an extensive microbiota and are frequently the site for asymptomatic carriage of bacterial pathogens. the goal of this study was to determine the composition of the microbial community of the tonsils in healthy pigs. tonsils were collected from eight pigs from two different healthy herds. samples of the tonsils from each pig were used for culture dependent and culture independent identification of the microbial community. aerobic ...201120663617
a surface protein of streptococcus suis serotype 2 identified by proteomics protects mice against infection.streptococcus suis serotype 2 is a major gram-positive swine pathogen, causing also zoonoses. we describe here the immunoprotective activity in an in vivo animal model of a serotype-2 cell wall protein, designated sat, which was identified by a previously validated proteomics approach consisting of the protease digestion of live bacteria and the selective recovery of exposed domains, followed by lc/ms/ms analysis. increased survival rate (80%) and decreased bacterial burden were observed in mice ...201020656083
pathogenicity and molecular characterization of emerging porcine reproductive and respiratory syndrome virus in vietnam in 2007.in 2007, vietnam experienced swine disease outbreaks causing clinical signs similar to the 'porcine high fever disease' that occurred in china during 2006. analysis of diagnostic samples from the disease outbreaks in vietnam identified porcine reproductive and respiratory syndrome virus (prrsv) and porcine circovirus type 2 (pcv-2). additionally, escherichia coli and streptococcus equi subspecies zooepidemicus were cultured from lung and spleen, and streptococcus suis from one spleen sample. gen ...201020629970
aerobic bacteria from mucous membranes, ear canals, and skin wounds of feral cats in grenada, and the antimicrobial drug susceptibility of major isolates.in a 2-year period 54 feral cats were captured in grenada, west indies, and a total of 383 samples consisting of swabs from rectum, vagina, ears, eyes, mouth, nose and wounds/abscesses, were cultured for aerobic bacteria and campylobacters. a total of 251 bacterial isolates were obtained, of which 205 were identified to species level and 46 to genus level. a commercial bacterial identification system (api/biomerieux), was used for this purpose. the most common species was escherichia coli (n=60) ...201120627391
vira: a virulence-related gene of streptococcus suis serotype 2.streptococcus suis serotype 2 is an important porcine and human zoonotic pathogen. few virulence factors have been identified and the pathogenesis of infection is not fully understood. we have identified a novel virulence-related gene, vira, of s. suis 2. to investigate its role in pathogenesis, a vira deletion mutant of s. suis 2 wild-type strain zy458, 458deltavir, was constructed using suicide vector pset4s, and a functionally complemented strain 458deltavir(pvir) was constructed using shuttl ...201020624451
streptococcus suis outbreak investigation using multiple-locus variable tandem repeat number analysis.two outbreaks of streptococcus suis st7 occurred in humans in 1998 and 2005 in china. pfge of chromosome restriction fragments found all st7 isolates to be indistinguishable. due to the genetic homogeneity of st7 isolates, development of a rapid sub-typing method with high discriminatory power for st7 isolates is required. in this study, a novel method, mlva, was developed to type s. suis serotype 2 strains. further, this method was used to analyze outbreak-associated st7 strains in china. a tot ...201020618684
the occurrence of bordetella bronchiseptica in pigs with clinical respiratory disease.between january 2003 and september 2008, 652 bordetella bronchiseptica isolates were cultured from 3506 lung samples collected from pigs with respiratory disease. over the 6-year period, the average isolation rate was 18.6%, making b. bronchiseptica the fourth most frequently isolated pathogenic bacterium from those lung samples. the isolation rates in different years and provinces ranged from 15.2% to 25.7% and 17.3% to 20.7%, respectively. there were significant influences of sampling month an ...201120598597
causes and time-course of vertigo in an ear, nose, and throat clinic.the purpose of this study is to review etiologies and identify the time-course of vertigo presenting in an ear, nose, and throat clinic, and serve as a reference guide for other clinics. the study includes retrospective chart review in a tertiary care, university hospital. the patient data with reported icd-10 codes as causes of vertigo between april 2005 and december 2007 were extracted from the database. at each visit, the main diagnosis as to etiology, characteristics of the vertigo, its time ...201020567978
structure determination of streptococcus suis serotype 2 capsular polysaccharide.the capsular polysaccharide (cps) of streptococcus suis serotype 2 was isolated, purified, chemically modified, and characterized. sugar and absolute configuration analyses of the cps gave the following composition: d-gal, 3; d-glc, 1; d-glcnac, 1; d-neu5ac, 1; l-rha, 1. sialic acid was found to be terminal, and the cps was quantitatively desialylated by mild acid hydrolysis. the cps was also submitted to periodate oxidation followed by borohydride reduction and smith degradation. sugar and meth ...201020555393
identification of streptococcus suis serotype 2 genes preferentially expressed in the natural host.streptococcus suis serotype 2 (ss2) is an important zoonotic pathogen for swine and humans. previous research about the mechanism of ss2 infection was largely established on in vitro or ex vivo models. in this study, we focused on the identification of ss2 genes preferentially expressed in vivo during natural infection in pigs. eighty ss2 genes were identified to be up-regulated in the porcine brains and lungs by selective capture of transcribed sequences (scots) and comparative dot blot analysi ...201020554247
synthesis of galabiose-chitosan conjugate as potent inhibitor of streptococcus suis adhesion.the aim of this work is to construct a safe and effective drug candidate against streptococcus suis infection. a panel of chitosan-based polymer conjugates with branched galabiose (galalpha1-4gal) side chains was synthesized as inhibitors of s. suis adhesion. the synthesis was achieved by using an aldehyde-functionalized galabiose derivative to graft it onto chitosan amino groups. structural compositions of the conjugates were verified by 1h nmr spectroscopy and chn elemental analyses. potent in ...201020540558
stimulating the development of national streptococcus suis guidelines in viet nam through a strategic research partnership.streptococcus suis is a common cause of adult bacterial meningitis in viet nam, and possibly other parts of asia, yet this disabling infection has been largely neglected. prevention, diagnosis and treatment are relatively straightforward and affordable but, in early 2007, no national diagnostic, case management or prevention guidelines existed in viet nam.201020539860
pathogenesis and antigenic characterization of a new east european subtype 3 porcine reproductive and respiratory syndrome virus isolate.porcine reproductive and respiratory syndrome virus (prrsv) is divided into a european and north american genotype. east european prrsv isolates have been found to be of the european genotype, but form different subtypes. in the present study, prrsv was isolated from a belarusian farm with reproductive and respiratory failure and designated "lena". analyses revealed that lena is a new east european subtype 3 prrsv isolate. the main purpose of this investigation was to study the pathogenesis and ...201020525333
apua, a multifunctional alpha-glucan-degrading enzyme of streptococcus suis, mediates adhesion to porcine epithelium and mucus.we have identified apua in streptococcus suis, which encodes a bifunctional amylopullulanase with conserved alpha-amylase and pullulanase substrate-binding domains and catalytic motifs. apua exhibited properties typical of a gram-positive surface protein, with a putative signal sequence and lpktge cell-wall-anchoring motif. a recombinant protein containing the predicted n-terminal alpha-amylase domain of apua was shown to have alpha-(1,4) glycosidic activity. additionally, an apua mutant of s. s ...201020522493
[prokaryotic expression and immunization of glutamyl trna synthetase of streptococcus suis].glutamyl trna synthetase (gts) is a protease which catalyzes esterification between trna and glutamine. the immunogenicity of gts was evaluated through immunization and challenge experiment.201020499650
[detection of bacterial meningitis by multiplex polymerase chain reaction].to develop a rapid method for detecting 8 pathogens which were highly related to bacterial meningitis by multiplex polymerase chain reaction.201020450073
detection of pathogenic streptococcus suis bacteria using magnetic glycoparticles.detection of the zoonotic bacterial pathogen streptococcus suis was achieved using magnetic glycoparticles. the bacteria contain an adhesion protein for the carbohydrate sequence galalpha1,4gal. after incubation with various amounts of the pathogen, magnetic concentration and atp detection, bacterial levels down to 10(5) cfu could be detected. submicrometer particles were needed, since with the larger microparticles the method did not succeed.201020448902
the alpha-enolase of streptococcus suis: a previously well-known and well-characterized protein. 201020429669
evaluation of the protective efficacy of a newly identified immunogenic protein, hp0272, of streptococcus suis.streptococcus suis serotype 2 (ss2) infection is a major cause of sudden death in pigs and is of concern for humans as it has strong zoonotic capabilities. developing novel effective vaccines would be beneficial to control ss2 infection. hp0272 is a novel immunogenic surface protein; its protective efficacy remains to be evaluated. the present mouse model found that the purified recombinant hp0272 could elicit a significant humoral antibody response, and to confer complete protection against a l ...201020402782
identification of a novel virulence-related gene in streptococcus suis type 2 strains.the trag is a novel infection-related factor identified using in vivo-induced antigen technology (iviat) from ss2 expression libraries with swine convalescent sera. pcr-based studies of various s. suis strains collected from different sources revealed that the trag gene was present in all the virulent ss2 strains, but absent in the avirulent t15 strain. pcr and southern hybridization analyses of a trag-knockout strain created through homologous recombination confirmed the coding sequence of trag ...201020386910
deafness due to haemorrhagic labyrinthitis and a review of relapses in streptococcus suis meningitis.deafness is a common and often permanent neurological sequel of streptococcus (s.) suis meningitis. suppurative labyrinthitis, rather than direct auditory nerve infection, has been found to be the site responsible for deafness. neuroimaging is important to localise the site involved in hearing loss and to assess the feasibility of a cochlear implantation. s. suis is very sensitive to penicillin. although a relapse of s. suis meningitis is uncommon, it can occur despite an adequate duration of ap ...201020358139
pleiotropic effects of polysaccharide capsule loss on selected biological properties of streptococcus suis.in this study, an unencapsulated streptococcus suis mutant was used to investigate the pleiotropic effects resulting from capsule loss. the capsule deficient mutant of s. suis acquired a biofilm-positive phenotype, which was associated with significantly increased cell surface hydrophobicity. cell-associated fibrinogen-binding and chymotrypsin-like activities were decreased in the unencapsulated mutant. the mutant did not differ significantly from the encapsulated parent strain for minimal inhib ...201020357962
identification of a novel angiogenin inhibitor 1 and its association with hyaluronidase of streptococcus suis serotype 2.to characterize the role of hyaluronidase (hyl) of streptococcus suis serotype 2 (s. suis 2), the hyla gene that encodes hyl was cloned, expressed and purified. a murine brain cdna library was used to screen for interacting proteins of hyl. employing the yeast two-hybrid system, a novel murine ribonuclease, angiogenin inhibitor 1 (ai1), which shares 93% homology with porcine ai1, was shown to interact with hyl in yeast. through co-immunoprecipitation assays, the interaction between ai1 and hyl w ...201020307645
[sequence analysis of 3 virulence factors from streptococcus suis serotype 2 isolates in zhejiang province]. 201020302714
quantification of the severity of an outbreak in human infection control.the severity of an outbreak is a priority in decision-making for human infection control. however, there have been no reports on how to quantify the severity of an outbreak.201020227902
streptococcus suis: a new emerging or an old neglected zoonotic pathogen?infections caused by streptococcus suis are considered a global and an economical problem in the swine industry. moreover, s. suis is an agent of zoonosis that afflicts people in close contact with infected pigs or pork-derived products. although sporadic cases of s. suis infections in humans (mainly meningitis) have been reported during the last 40 years, a large outbreak due to this pathogen emerged in the summer of 2005 in china. the severity of the infection in humans during the outbreak, su ...201020210549
transcriptome profiling of zebrafish infected with streptococcus suis.streptococcus suis is an important pathogen in swine, and it also represents an emerging zoonotic agent. zebrafish as a model for the evaluation of virulence of s. suis has been demonstrated before. here, an affymetrix zebrafish genechip was used to identify alterations in gene expression of zebrafish injected with s. suis serotype 2 strain ha9801. the results showed that 189 genes were differentially expressed, of which 125 genes were upregulated and 64 genes were downregulated. gene ontology c ...201020206250
occurrence of mycoplasma hyopneumoniae infections in suckling and nursery pigs in a region of high pig density.the occurrence of mycoplasma hyopneumoniae infections in young pigs was surveyed in a retrospective study of 1122 datasets obtained from routine diagnostics where either suckling or nursery pigs were examined for m hyopneumoniae in lung tissue. findings were correlated with the presence of lung lesions, detection of other respiratory pathogens, vaccination history and parameters describing the herd of origin. the prevalence of m hyopneumoniae in lung tissue from 201 suckling pigs was 2.0 per cen ...201020154309
the cell envelope subtilisin-like proteinase is a virulence determinant for streptococcus suis.streptococcus suis is a major swine pathogen and zoonotic agent that mainly causes septicemia, meningitis, and endocarditis. it has recently been suggested that proteinases produced by s. suis (serotype 2) are potential virulence determinants. in the present study, we screened a s. suis mutant library created by the insertion of tn917 transposon in order to isolate a mutant deficient in a cell surface proteinase. we characterized the gene and assessed the proteinase for its potential as a virule ...201020146817
the cation-uptake regulators adcr and fur are necessary for full virulence of streptococcus suis.in streptococci, the pleiotropic regulators adcr and fur control the transport of, zinc and iron, respectively, which are essential components of many proteins. in this work, deltaadcr, deltafur, and deltaadcr deltafur mutants of streptococcus suis, a serious pathogen in pigs and humans, were assayed in a mouse model to determine their involvement in the virulence of this bacterium. the results showed, for the first time, that the virulence of s. suis mutants carrying an inactivation of adcr, fu ...201020133089
immunoprotective activities of a streptococcus suis pilus subunit in murine models of infection.pili of gram-positive bacteria are key virulence factors and their subunits are considered excellent vaccine candidates. streptococcus suis is an emerging zoonotic agent that can cause epidemics of life-threatening infections in humans, but the functional role or immunoprotective potential of its pilus components have not been studied yet. using a selective proteomics approach, we have identified a surface protein of serotype 2 s. suis showing features of an ancillary pilus subunit, as evidenced ...201020079873
uncovering newly emerging variants of streptococcus suis, an important zoonotic agent.streptococcus suis is recognized as a major swine pathogen and an emerging zoonotic agent. two large-scale outbreaks of severe s. suis epidemics occurred in china in 1998 and 2005 that posed serious concerns to public health and challenged the conventional conception that opportunistic infections of s. suis serotype 2 (ss2) in humans were only sporadic cases. an extensive, collaborative study on chinese ss2 variants, which exhibit strong invasiveness and high pathogenicity, has resulted in the d ...201020071175
mutations in the gene encoding the ancillary pilin subunit of the streptococcus suis srtf cluster result in pili formed by the major subunit only.pili have been shown to contribute to the virulence of different gram-positive pathogenic species. among other critical steps of bacterial pathogenesis, these structures participate in adherence to host cells, colonization and systemic virulence. recently, the presence of at least four discrete gene clusters encoding putative pili has been revealed in the major swine pathogen and emerging zoonotic agent streptococcus suis. however, pili production by this species has not yet been demonstrated. i ...201020052283
differential activation of the toll-like receptor 2/6 complex by lipoproteins of streptococcus suis serotypes 2 and 9.streptococcus suis causes invasive infections in pigs and occasionally in humans. worldwide, s. suis serotype 2 is most frequently isolated from diseased piglets, but the less virulent serotype 9 is emerging, at least in europe. we compared the activation of human toll-like receptors (htlrs) by s. suis serotype 2 and 9 strains to better understand the role of the innate immune response in fighting s. suis infections. neither live nor heat-killed log phase grown s. suis activated the htlr1/2, htl ...201020044219
streptococcus suis meningitis, hawaii. 200919961708
identification of a cell wall-associated subtilisin-like serine protease involved in the pathogenesis of streptococcus suis serotype 2.streptococcus suis is an important swine and human pathogen, and also an emerging zoonotic agent. a surface-associated subtilisin-like serine protease (sspa) of s. suis was identified by screening a genomic expression library as fragments of this protein reacted most strongly with convalescent-phase pig sera. the sspa gene is present in 29 of 33 s. suis serotypes reference strains and is expressed on the surface of s. suis. relative real-time quantitative pcr assay demonstrated that sspa mrna ex ...201019944142
emergence of a cell wall protease in the streptococcus thermophilus population.streptococcus thermophilus is perceived as a recently emerged food bacterium that evolved from a commensal ancestor by loss and gain of functions. here, we provide data allowing a better understanding of this evolutionary scheme. a multilocus sequence typing approach that we developed showed that s. thermophilus diverges significantly from its potential ancestors of the salivarius group and displays a low level of allelic variability, confirming its likely recent emergence. an analysis of the or ...201019915034
[a case of streptococcus suis endocarditis, probably bovine-transmitted, complicated by pulmonary embolism and spondylitis].streptococcus suis, a major global porcine pathogen, is an emerging zoonosis in southeast asia that triggered a 2005 outbreak in china. s. suis causes meningitis, sepsis, and endocarditis in both pigs and humans and involves significant mortality. we report the case of a previously healthy 50-year-old dairy farmer who developed s. suis type 2 endocarditis complicated by pulmonary embolism and spondylitis. he experienced a high fever, chills, fatigue, and worsening low back pain in the 6 weeks pr ...200919860257
characterization of a virulence-associated and cell-wall-located dnase of streptococcus pyogenes.we investigated culture supernatant proteins from the m1 serotype of streptococcus pyogenes by two-dimensional gel electrophoresis and peptide mass mapping analysis, and characterized the single protein spots. among them, we analysed the spy0747 protein. this protein is homologous to the ssna protein, a cell-wall-located dnase expressed in streptococcus suis serotype 2. we designated the spy0747 protein as spna. spna protein was also detected in the insoluble fraction of whole-cell lysates using ...201019850619
streptococcus suis enolase functions as a protective antigen displayed on the bacterial cell surface.streptococcus suis serotype 2 (ss2) has evolved into a highly infectious entity, posing a great threat to public health. screening for and identification of protective antigens plays an important role in developing therapies against ss2 infections.200919848587
streptococcus suis infection: a prospective study in northern thailand.a prospective study of all cases of streptococcus suis blood or csf culture positive admitted to lamphun provincial hospital in northern thailand was carried out. fifty-three cases of s. suis were identified, which comprised 70% of all viridans streptococci cases. the majority of cases (88.6%) were contracted orally and 83.0% had an underlying disease present. five clinical syndromes were identified: acute meningitis (37.2%), septicemia (27.9%), toxic shock syndrome (tss) (23.3%), subacute bacte ...200919842437
genetic analysis of streptococcus suis isolates recovered from diseased and healthy carrier pigs at different stages of production on a pig farm.streptococcus suis isolates from pigs at different stages of production on a farrow-to-finish farm were characterised by serotyping, pulsed-field gel electrophoresis (pfge) and production of muramidase-released protein, extracellular factor and suilysin. s. suis was isolated from the tonsils of 81/287 (28.2%) healthy pigs: 16/47 (34%) post-weaning, 18/47 (38.3%) transition, 18/47 (38.3%) fattening and 29/146 (19.9%) sows. a total of 127 s. suis isolates were analysed: 14 from diseased pigs at th ...201019800823
mycotic abdominal aortic aneurysm due to streptococcus suis: a case report.streptococcus suis is a common infection of pigs. human infection is often related to accidental inoculation through skin injuries during occupational exposure to pigs and pork. the disease may present as meningitis, bacteremia, and less commonly endocarditis, arthritis, or bronchopneumonia.201019795992
contribution of the feob transporter to streptococcus suis virulence.the contribution of iron transporter systems encoded by feo genes to the pathogenic traits of streptococci is largely unknown, despite the fact that those systems are required for the full virulence of several gram-negative bacterial species. in this work, we show that the swine pathogen and zoonotic agent streptococcus suis has a feoab operon similar to that encoding an iron transporter system in escherichia coli. electrophoretic mobility assays and transcriptional analyses confirmed that the e ...200919784934
genetic and virulence-phenotype characterization of serotypes 2 and 9 of streptococcus suis swine isolates.the aim of this study was to analyze the genetic characteristics and virulence phenotypes of streptococcus suis, specifically, in clinical isolates of serotypes 2 and 9 (n = 195), obtained from diverse geographical areas across spain. pulsed-field gel electrophoresis (pfge) typing identified 97 genetic profiles, 68% of which were represented by single isolates, indicative of a substantial genetic diversity among the s. suis isolates analyzed. five pfge profiles accounted for 33.3% of the isolate ...200919784922
use of in vivo-induced antigen technology (iviat) for the identification of streptococcus suis serotype 2 in vivo-induced bacterial protein antigens.streptococcus suis serotype 2 (ss2) is a zoonotic agent that causes death and disease in both humans and swine. a better understanding of ss2-host molecular interactions is crucial for understanding ss2 pathogenesis and immunology. conventional genetic and biochemical approaches used to study ss2 virulence factors are unable to take into account the complex and dynamic environmental stimuli associated with the infection process. in this study, in vivo-induced antigen technology (iviat), an immun ...200919765272
identification and characterization of inosine 5-monophosphate dehydrogenase in streptococcus suis type 2.streptococcus suis type 2 is a swine pathogen responsible for diverse diseases. although many virulent factors have been identified and studied, relatively little is known about the pathogenic mechanisms of type 2. the aim of the study was to identify and understand the characterization of inosine 5-monophosphate dehydrogenase (impdh). a 957-bp gene, impdh, was identified in the virulent s. suis serotype 2 (ss2), and analysis of the predicted impdh sequence revealed imp dehydrogenase/gmp reducta ...200919744553
development of colloidal gold-based immunochromatographic assay for rapid detection of streptococcus suis serotype 2.to develop colloidal gold immunochromatographic strips for the direct detection of the streptococcus suis serotype 2 antigen, colloidal gold was prepared by reduction of a gold salt with sodium citrate and coupled with polyclonal antibody against s. suis serotype 2. the optimal concentrations of the capture antibody and the coating antibody were determined to be 22mug/ml and 2.0mg/ml, respectively, and that of the blocking buffer was determined to be 1.5% bovine serum albumin. different serotype ...201019733402
genetic diversity of streptococcus suis clinical isolates from pigs and humans in italy (2003-2007).streptococcus suis, a major porcine pathogen, is emerging as a zoonotic agent capable of causing severe invasive disease in humans exposed to pigs or pork products. s. suis infection is rare in industrialised countries and usually arises as sporadic cases, with meningitis the most common clinical presentation in humans. recent reports of two cases of meningitis in sardinia and northeastern italy prompted this first characterisation of italian s. suis isolates. fifty-nine s. suis strains, the two ...200919712640
involvement of nf-kappab and map-kinases in the transcriptional response of alveolar macrophages to streptococcus suis.interaction of streptococcus suis with primary porcine alveolar macrophages was studied using transcriptomics. transcriptional response of macrophages to two different s. suis strains was studied: wild-type s10 that is resistant to phagocytosis, and its non-encapsulated mutant that is phagocytosed efficiently. the macrophages' transcriptional response was observed only after 60 min of incubation. eleven genes were expressed significantly different between macrophages infected with streptococci a ...201019709818
avian influenza virus, streptococcus suis serotype 2, severe acute respiratory syndrome-coronavirus and beyond: molecular epidemiology, ecology and the situation in china.the outbreak and spread of severe acute respiratory syndrome-associated coronavirus and the subsequent identification of its animal origin study have heightened the world's awareness of animal-borne or zoonotic pathogens. in addition to sars, the highly pathogenic avian influenza virus (aiv), h5n1, and the lower pathogenicity h9n2 aiv have expanded their host ranges to infect human beings and other mammalian species as well as birds. even the 'well-known' reservoir animals for influenza virus, m ...200919687041
[biological profiles of recombinant suilysin].to provide insights into the role of suilysin in the pathogenesis of streptococcus suis by analysing the biological profiles of recombinant suilysin (rsly).200919673416
clonal dissemination of human isolates of streptococcus suis serotype 14 in thailand.most cases of streptococcus suis infection in humans are caused by serotype 2 strains, and only a few cases caused by other serotypes have been reported. among 177 human isolates of s. suis in thailand, 12 (6.8 %) were identified as being of serotype 14, and an occurrence of sporadic s. suis serotype 14 infection was noted during 2006-2008, particularly in northern thailand. clinical presentations of the 12 patients (median age 62.9 years) included meningitis (58.3 %), septic arthritis (25 %) an ...200919661209
streptococcus porci sp. nov., isolated from swine sources.two unidentified gram-positive, catalase-negative, coccus-shaped organisms were recovered from pigs and subjected to a polyphasic taxonomic analysis. based on cellular morphology and biochemical criteria, the isolates were tentatively assigned to the genus streptococcus, although the organisms did not appear to correspond to any recognized species. comparative 16s rrna gene sequence studies confirmed this identification and showed that the nearest phylogenetic relatives of the unknown cocci were ...201019648324
[distributions of pathogenic capsular types and in vitro antimicrobial susceptibility of different serotypes of streptococcus suis isolated from clinically healthy sows from 10 provinces in china].to determine the distributions of major pathogenic capsular types and in vitro antimicrobial susceptibility of different serotypes of streptococcus suis isolated from clinically healthy sows in china.200919642376
[prokaryotic expression of recombinant streptococcus suis igg binding protein and its binding activity with igg].streptococcus suis (s. suis) igg-binding protein (spg) was present in all s. suis strains examined. it showed binding activities with igg from various host species. little was known about the biological role of this protein, but it was commonly believed that it acted as virulence factor. in this study, the genes encoding spg were amplified respectively from the total dna of the s. suis serotype 1/2, 1, 2 and 9 with pcr and expressed in escherichia coli bl21 by plasmid pet28a as vector. the recom ...200919637623
identification and characterization of iga1 protease from streptococcus suis.streptococcus suis (s. suis) is a major swine pathogen and an emerging zoonotic agent. however, the current understanding of the s. suis pathogenesis of infection remains limited. in the present study, an iga1 protease of s. suis was identified for the first time. the protein was recombinantly expressed in escherichia coli, and the purified recombinant protein showed good cleaving reactivity to iga1 and was highly immunoreactive to convalescent sera. the gene was found to exist in most pathogeni ...201019619964
crystal structures of streptococcus suis mannonate dehydratase (mand) and its complex with substrate: genetic and biochemical evidence for a catalytic mechanism.mannonate dehydratase (mand) is found only in certain bacterial species, where it participates in the dissimilation of glucuronate. mand catalyzes the dehydration of d-mannonate to yield 2-keto-3-deoxygluconate (2-kdg), the carbon and energy source for growth. selective inactivation of mand by drug targeting is of therapeutic interest in the treatment of human streptococcus suis infections. here, we report the overexpression, purification, functional characterization, and crystallographic struct ...200919617363
screening of binding activity of streptococcus pneumoniae, streptococcus agalactiae and streptococcus suis to berries and juices.antiadhesion therapy is a promising approach to the fight against pathogens. antibiotic resistance and the lack of effective vaccines have increased the search for new methods to prevent infectious diseases. previous studies have shown the antiadhesion activity of juice from cultivated cranberries (vaccinium macrocarpon ait.) against bacteria, especially e. coli. in this study, the binding of two streptococcal strains, streptococcus pneumoniae and streptococcus agalactiae, to molecular size frac ...201019610031
rapid evolution of virulence and drug resistance in the emerging zoonotic pathogen streptococcus suis.streptococcus suis is a zoonotic pathogen that infects pigs and can occasionally cause serious infections in humans. s. suis infections occur sporadically in human europe and north america, but a recent major outbreak has been described in china with high levels of mortality. the mechanisms of s. suis pathogenesis in humans and pigs are poorly understood.200919603075
serotype distribution and production of muramidase-released protein, extracellular factor and suilysin by field strains of streptococcus suis isolated in the united states.streptococcus suis is an important swine pathogen and a zoonotic agent. differences in virulence have been noted among the 33 described serotypes, serotype 2 being considered the most virulent. in this study, we aimed at assessing the serotype distribution and the production of virulence-associated markers by strains recovered from diseased pigs in the united states (u.s.). results showed that among the 100 strains evaluated, serotype 3 (20% of the isolates) and serotype 2 (17%) were the most pr ...200919596529
identification of a surface protective antigen, hp0197 of streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is a porcine and human pathogen with adhesive and invasive properties. as traditional inactive vaccine has obvious shortcomings, to identify protective antigens would undoubtedly contribute to the development of novel vaccines. hp0197 has been identified as immunogenic protein in the previous study but its protective efficacy was not clear. in the present study, the purified recombinant hp0197 protein could elicit a significant humoral antibody response and co ...200919596417
surface-associated and secreted factors of streptococcus suis in epidemiology, pathogenesis and vaccine development.streptococcus suis is an invasive porcine pathogen associated with meningitis, arthritis, bronchopneumonia and other diseases. the pathogen constitutes a major health problem in the swine industry worldwide. furthermore, s. suis is an important zoonotic agent causing meningitis and other diseases in humans exposed to pigs or pork. current knowledge on pathogenesis is limited, despite the enormous amount of data generated by 'omics' research. accordingly, immunoprophylaxis (in pigs) is hampered b ...200919558750
streptococcus suis, an important cause of adult bacterial meningitis in northern vietnam.streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. s. suis is often misdiagnosed, due to lack of awareness and improper testing. here we report the first fifty cases diagnosed with s. suis infection in northern viet nam.200919543404
recurrence of human streptococcus suis infections in 2007: three cases of meningitis and implications that heterogeneous s. suis 2 circulates in china.emergence of fatal streptococcus suis serotype 2 (s. suis 2, ss2) in china, 2005, has greatly challenged the public health, raising serious concerns about its global circulation. whole genome sequencing of the representative strains has identified a potential pathogenicity island (pai), named 89k. here, we reported the recurrence of human s. suis meningitis cases (two in shenzhen city and one in sichuan province) in china, in 2007. multiple lines of evidence supported that these human cases are ...200919538458
intranasal immunization with a live streptococcus suis isogenic ofs mutant elicited suilysin-neutralization titers but failed to induce opsonizing antibodies and protection.in europe, streptococcus suis serotypes 2 and 9 are very important causative agents of meningitis, arthritis and septicemia in piglets. so far, no vaccine has been described which elicits protection against both serotypes. the working hypothesis of this study was that an isogenic serotype 2 mutant attenuated in virulence but not in colonization of the respiratory tract might induce protective immunity against both serotypes. piglets were immunized with the attenuated s. suis serotype 2 strain 10 ...200919505730
immunization with sseno fails to protect mice against challenge with streptococcus suis serotype 2.in our ongoing efforts to develop a vaccine against streptococcus suis infection, we tested the potential of s. suis enolase (sseno), a recently described s. suis adhesin with fibronectin-binding activity, as a vaccine candidate in a mouse model of s. suis-induced septicemia and meningitis. here, we show that sseno is highly recognized by sera from convalescent pigs and is highly immunogenic in mice. subcutaneous immunization of mice with sseno elicited strong immunoglobulin g (igg) antibody res ...200919493012
biological activity and identification of a peptide inhibitor of luxs from streptococcus suis serotype 2.the virulence of bacterial communities may be regulated by mechanisms involving the synthesis of the quorum-sensing signal autoinducer 2 (ai-2), which allows both intra- and interspecies communication. ai-2 is produced in bacteria that express the gene luxs. in the present study, expressed and purified luxs from streptococcus suis serotype 2 (ss2) was used to catalyze the substrate s-ribosylhomocysteine in a reaction that leads to the production of ai-2. the biological activity of the in vitro s ...200919493004
inactivation of dipeptidyl peptidase iv attenuates the virulence of streptococcus suis serotype 2 that causes streptococcal toxic shock syndrome.di-peptidyl peptidase iv (dpp iv), originally recognized as cd26 in eukaryotic cells, is distributed widely in microbial pathogens, including streptococcus suis (s. suis), an emerging zoonotic agent. however, the role of dpp iv in s. suis virulence remains unclear. here, we identified a dpp iv homologue from highly invasive isolate of s. suis 2 (ss2) causing streptococcal toxic shock syndrome (stss). enzymatic assays reproduced its enzymatic activity of dpp iv protein product as a functional dpp ...200919484301
identification of three novel in vivo-induced expressed antigens during infection with streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is a porcine and human pathogen with adhesive and invasive properties. the shortage of studies on the pathogenesis mechanisms of ss2 has made it very difficult to control infection with this pathogen. three novel in vivo-induced antigens were identified using serological proteome analysis of the ss2 cell wall-associated proteins--seca, autolysin and znua--the upregulation of which in vivo relative to in vitro was shown by real-time pcr analysis. the in vivo-in ...200919473247
vaccination with streptococcus suis serotype 2 recombinant 6pgd protein provides protection against s. suis infection in swine.streptococcus suis serotype 2 (s. suis 2 or ss2) is the causative agent of several diseases in both pigs and humans. 6-phosphogluconate dehydrogenase (6pgd) is a cell surface protein in ss2. in this study, the immunogenicity and protective efficacy of recombinant 6pgd (r6pgd) from ss2 was evaluated in piglets. immunization with an r6pgd-containing adjuvant induced a vigorous immunoglobulin g (igg) response, with the titer of igg2 being higher than that of igg1. immunization of piglets with r6pgd ...200919459970
contribution of glutamine synthetase to the virulence of streptococcus suis serotype 2.streptococcus suis serotype 2 (s. suis 2) is an important pathogen, responsible for diverse diseases in swine and human. in this study, we investigated the role of the glutamine synthetase (glna) in the pathogenesis of s. suis 2 in mice. to assess the contribution of glutamine synthetase (glna) to the virulence of s. suis 2, an knockout mutant (deltaglna) unable to produce glna was constructed, and the virulence level of wild-type (wt) sc19 and the deltaglna mutant strain were compared in an in ...200919447571
[acute infective endocarditis due to streptococcus suis serotype 2 in spain]. 200919442415
streptococcus suis meningitis in adults in vietnam.streptococcus suis infection is an emerging zoonosis in asia. we determined the detailed epidemiological, clinical, and microbiological characteristics of s. suis meningitis in adults.200819413493
[acute meningitis and spondylodiscitis due to streptococcus suis in a patient who had no contact with pigs or porcine products]. 200919403208
expression levels of immune markers in actinobacillus pleuropneumoniae infected pigs and their relation to breed and clinical symptoms.in pigs little is known about the role of innate immune defence in bacterial infections of the respiratory tract, despite their major role in pig production. in the present study we characterized and compared in vitro and in vivo activation of immune markers of different pig breeds 7 days before, and 4 and 21 days after an experimental aerosol infection with actinobacillus (a.) pleuropneumoniae.200919383119
resistance to tetracycline, erythromycin and clindamycin in streptococcus suis serotype 2 in hong kong. 200919380213
protective capacities of cell surface-associated proteins of streptococcus suis mutants deficient in divalent cation-uptake regulators.many cell surface-associated, divalent cation-regulated proteins are immunogenic, and some of them confer protection against the bacterial species from which they are derived. in this work, two streptococcus suis divalent cation uptake regulator genes controlling zinc/manganese and iron uptake (adcr and fur, respectively) were inactivated in order to study the protective capacities of their cell surface-associated proteins. the results obtained showed overexpression of a set of immunogenic prote ...200919372168
association of streptococcus pluranimalium with valvular endocarditis and septicaemia in adult broiler parents.the genus streptococcus consists of more than 60 species, but only streptococcus equi subspecies zooepidemicus, streptococcus gallolyticus ssp. gallolyticus, streptococcus gallinaceus, streptococcus dysgalactiae, streptococcus mutans and streptococcus suis have been isolated from poultry. during investigations of the aetiology of increased mortality in broiler parent stock at the end of production, pure cultures of streptococcal-like organisms that could not be classified among these six species ...200919322715
[streptococcus suis meningitis in spain]. 200919306723
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