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1.
Laetitia Bonifait Maria de la Cruz Dominguez-Punaro Katy Vaillancourt Christian Bart Josh Slater Michel Frenette Marcelo Gottschalk Daniel Grenier 《BMC microbiology》2010,10(1):42
Background
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 virulence factor. 相似文献2.
Streptococcus suis, more particularly serotype 2, is a major swine pathogen and an emerging zoonotic agent worldwide that mainly causes meningitis, septicemia, endocarditis, and pneumonia. Although several potential virulence factors produced by S. suis have been identified in the last decade, the pathogenesis of S. suis infections is still not fully understood. In the present study, we showed that S. suis produces membrane vesicles (MVs) that range in diameter from 13 to 130 nm and that appear to be coated by capsular material. A proteomic analysis of the MVs revealed that they contain 46 proteins, 9 of which are considered as proven or suspected virulence factors. Biological assays confirmed that S. suis MVs possess active subtilisin-like protease (SspA) and DNase (SsnA). S. suis MVs degraded neutrophil extracellular traps, a property that may contribute to the ability of the bacterium to escape the host defense response. MVs also activated the nuclear factor-kappa B (NF-κB) signaling pathway in both monocytes and macrophages, inducing the secretion of pro-inflammatory cytokines, which may in turn contribute to increase the permeability of the blood brain barrier. The present study brought evidence that S. suis MVs may play a role as a virulence factor in the pathogenesis of S. suis infections, and given their composition be an excellent candidate for vaccine development. 相似文献
3.
Christian Spoerry Jana Seele Peter Valentin-Weigand Christoph G. Baums Ulrich von Pawel-Rammingen 《The Journal of biological chemistry》2016,291(15):7915-7925
Streptococcus suis is a major endemic pathogen of pigs causing meningitis, arthritis, and other diseases. Zoonotic S. suis infections are emerging in humans causing similar pathologies as well as severe conditions such as toxic shock-like syndrome. Recently, we discovered an IdeS family protease of S. suis that exclusively cleaves porcine IgM and represents the first virulence factor described, linking S. suis to pigs as their natural host. Here we report the identification and characterization of a novel, unrelated protease of S. suis that exclusively targets porcine IgG. This enzyme, designated IgdE for immunoglobulin G-degrading enzyme of S. suis, is a cysteine protease distinct from previous characterized streptococcal immunoglobulin degrading proteases of the IdeS family and mediates efficient cleavage of the hinge region of porcine IgG with a high degree of specificity. The findings that all S. suis strains investigated possess the IgG proteolytic activity and that piglet serum samples contain specific antibodies against IgdE strongly indicate that the protease is expressed in vivo during infection and represents a novel and putative important bacterial virulence/colonization determinant, and a thus potential therapeutic target. 相似文献
4.
Heiman F. L. Wertheim Huyen Nguyen Nguyen Walter Taylor Trinh Thi Minh Lien Hoa Thi Ngo Thai Quoc Nguyen Bich Ngoc Thi Nguyen Ha Hong Nguyen Ha Minh Nguyen Cap Trung Nguyen Trinh Tuyet Dao Trung Vu Nguyen Annette Fox Jeremy Farrar Constance Schultsz Hien Duc Nguyen Kinh Van Nguyen Peter Horby 《PloS one》2009,4(6)
Background
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.Methodology/Principal Findings
In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months.Conclusions/Significance
S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen. 相似文献5.
Neutrophil extracellular trap formation in the Streptococcus suis‐infected cerebrospinal fluid compartment
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Nicole de Buhr Friederike Reuner Ariane Neumann Carolin Stump‐Guthier Tobias Tenenbaum Horst Schroten Hiroshi Ishikawa Kristin Müller Andreas Beineke Isabel Hennig‐Pauka Thomas Gutsmann Peter Valentin‐Weigand Maren von Köckritz‐Blickwede 《Cellular microbiology》2017,19(2)
6.
Juan Li Li Yu Jinkui Yang Linqian Dong Baoyu Tian Zefen Yu Lianming Liang Ying Zhang Xu Wang Keqin Zhang 《BMC evolutionary biology》2010,10(1):68
Background
Subtilisin-like serine proteases play an important role in pathogenic fungi during the penetration and colonization of their hosts. In this study, we perform an evolutionary analysis of the subtilisin-like serine protease genes of subphylum Pezizomycotina to find if there are similar pathogenic mechanisms among the pathogenic fungi with different life styles, which utilize subtilisin-like serine proteases as virulence factors. Within Pezizomycotina, nematode-trapping fungi are unique because they capture soil nematodes using specialized trapping devices. Increasing evidence suggests subtilisin-like serine proteases from nematode-trapping fungi are involved in the penetration and digestion of nematode cuticles. Here we also conduct positive selection analysis on the subtilisin-like serine protease genes from nematode-trapping fungi. 相似文献7.
Nghia HD Ho DT Tu le TP Le TP Wolbers M Thai CQ Cao QT Hoang NV Nguyen VM Nga TV Tran VT Thao le TP Le TP Phu NH Nguyen HP Chau TT Tran TH Sinh DX Dinh XS Diep TS To SD Hang HT Hoang TT Truong H Campbell J Chau NV Nguyen VV Chinh NT Nguyen TC Dung NV Nguyen VD Hoa NT Ngo TH Spratt BG Hien TT Tran TH Farrar J Schultsz C 《PloS one》2011,6(3):e17604
Background
Streptococcus suis infection, an emerging zoonosis, is an increasing public health problem across South East Asia and the most common cause of acute bacterial meningitis in adults in Vietnam. Little is known of the risk factors underlying the disease.Methods and Findings
A case-control study with appropriate hospital and matched community controls for each patient was conducted between May 2006 and June 2009. Potential risk factors were assessed using a standardized questionnaire and investigation of throat and rectal S. suis carriage in cases, controls and their pigs, using real-time PCR and culture of swab samples. We recruited 101 cases of S. suis meningitis, 303 hospital controls and 300 community controls. By multivariate analysis, risk factors identified for S. suis infection as compared to either control group included eating “high risk” dishes, including such dishes as undercooked pig blood and pig intestine (OR1 = 2.22; 95%CI = [1.15–4.28] and OR2 = 4.44; 95%CI = [2.15–9.15]), occupations related to pigs (OR1 = 3.84; 95%CI = [1.32–11.11] and OR2 = 5.52; 95%CI = [1.49–20.39]), and exposures to pigs or pork in the presence of skin injuries (OR1 = 7.48; 95%CI = [1.97–28.44] and OR2 = 15.96; 95%CI = [2.97–85.72]). S. suis specific DNA was detected in rectal and throat swabs of 6 patients and was cultured from 2 rectal samples, but was not detected in such samples of 1522 healthy individuals or patients without S. suis infection.Conclusions
This case control study, the largest prospective epidemiological assessment of this disease, has identified the most important risk factors associated with S. suis bacterial meningitis to be eating ‘high risk’ dishes popular in parts of Asia, occupational exposure to pigs and pig products, and preparation of pork in the presence of skin lesions. These risk factors can be addressed in public health campaigns aimed at preventing S. suis infection. 相似文献8.
Anusha van Samkar Matthijs C. Brouwer Constance Schultsz Arie van der Ende Diederik van de Beek 《PLoS neglected tropical diseases》2015,9(10)
Background
Streptococcus suis is the most common cause of meningitis in pork consuming and pig rearing countries in South-East Asia. We performed a systematic review of studies on S. suis meningitis to define the clinical characteristics, predisposing factors and outcome.Methodology
Studies published between January 1, 1980 and August 1, 2015 were identified from main literature databases and reference lists. Studies were included if they were written in West-European languages and described at least 5 adult patients with S. suis meningitis in whom at least one clinical characteristic was described.Findings
We identified 913 patients with S. suis meningitis included in 24 studies between 1980 and 2015. The mean age was 49 years and 581 of 711 patients were male (82%). Exposure to pigs or pork was present in 395 of 648 patients (61%) while other predisposing factors were less common. 514 of 528 patients presented with fever (97%), 429 of 451 with headache (95%), 462 of 496 with neck stiffness (93%) and 78 of 384 patients (20%) had a skin injury in the presence of pig/pork contact. The case fatality rate was 2.9% and hearing loss was a common sequel occurring in 259 of 489 patients (53%). Treatment included dexamethasone in 157 of 300 (52%) of patients and was associated with reduced hearing loss in S. suis meningitis patients included in a randomized controlled trial.Conclusion
S. suis meningitis has a clear association with pig and pork contact. Mortality is low, but hearing loss occurs frequently. Dexamethasone was shown to reduce hearing loss. 相似文献9.
Kathrin M Felder Katharina Hoelzle Karl Heinritzi Mathias Ritzmann Ludwig E Hoelzle 《BMC veterinary research》2010,6(1):18
Background
In autoimmune haemolytic anaemia (AIHA), autoreactive antibodies directed against red blood cells are up-regulated, leading to erythrocyte death. Mycoplasma suis infections in pigs induce AIHA of both the warm and cold types. The aim of this study was to identify the target autoantigens of warm autoreactive IgG antibodies. Sera from experimentally M. suis-infected pigs were screened for autoreactivity. 相似文献10.
11.
Xiaojing Xia Xin Wang Xiaobing Wei Jinqing Jiang Jianhe Hu 《Antonie van Leeuwenhoek》2018,111(12):2233-2247
One of the most important zoonotic pathogens worldwide, Streptococcus suis is a swine pathogen that is responsible for meningitis, toxic shock and even death in humans. S. suis infection develops rapidly with nonspecific clinical symptoms in the early stages and a high fatality rate. Recently, much attention has been paid to the high prevalence of S. suis as well as the increasing incidence and its epidemic characteristics. As laboratory-acquired infections of S. suis can occur and it is dangerous to public health security, timely and early diagnosis has become key to controlling S. suis prevalence. Here, the techniques that have been used for the detection, typing and characterization of S. suis are reviewed and the prospects for future detection methods for this bacterium are also discussed. 相似文献
12.
Schwerk C Adam R Borkowski J Schneider H Klenk M Zink S Quednau N Schmidt N Stump C Sagar A Spellerberg B Tenenbaum T Koczan D Klein-Hitpass L Schroten H 《Microbes and infection / Institut Pasteur》2011,13(11):953-962
The Gram-positive zoonotic bacterium Streptococcus suis (S. suis) is responsible for a wide range of diseases including meningitis in pigs and humans. The blood-cerebrospinal fluid (CSF) barrier is constituted by the epithelial cells of the choroid plexus, which execute barrier function also after bacteria have entered the central nervous system (CNS). We show that the bacterial capsule, a major virulence factor, strongly attenuates adhesion of S. suis to the apical side of porcine choroid plexus epithelial cells (PCPEC). Oligonucleotide microarray analysis and quantitative PCR surprisingly demonstrated that adherent wild-type and capsule-deficient S. suis influenced expression of a pronounced similar pattern of genes in PCPEC. Investigation of purified capsular material provided no evidence for a significant role of the capsule. Enriched among the regulated genes were those involved in “inflammatory response”, “defense response” and “cytokine activity”. These comprised several cytokines and chemokines including the interleukins 6 and 8, which could be detected on protein level. We show that after infection with S. suis the choroid plexus contributes to the immune response by actively producing cytokines and chemokines. Other virulence factors than the bacterial capsule may be relevant in inducing a strong inflammatory response in the CNS during S. suis meningitis. 相似文献
13.
猪链球菌分子流行病学研究方法 总被引:1,自引:0,他引:1
猪链球菌(Streptococcus suis)是猪重要的细菌性病原,它可以导致猪的脑膜炎、败血症和关节炎等症状,给养猪业带来严重经济损失;同时该菌还可感染人,是一种人畜共患病原菌。应用分子流行病学方法,阐明猪链球菌病的流行病学特征,明确其毒力分型、时空分布、传播途径、传染源,确定传播的遗传决定因素等,将有助于猪链球菌病的防控。目前常用的分子流行病学方法主要有多位点序列分型、脉冲场凝胶电泳、全基因组测序和基于PCR的方法等。本文介绍了上述方法的原理以及在猪链球菌流行病学中的应用,并分析这几种方法的优缺点,从而为更好地揭示猪链球菌流行病学特征、制定猪链球菌病的防控策略提供参考。 相似文献
14.
Background
Streptococcus suis infections are a serious problem for both humans and pigs worldwide. The emergence and increasing prevalence of antibiotic-resistant S. suis strains pose significant clinical and societal challenges.Results
In our study, we sequenced one multi-drug-resistant S. suis strain, R61, and one S. suis strain, A7, which is fully sensitive to all tested antibiotics. Comparative genomic analysis revealed that the R61 strain is phylogenetically distinct from other S. suis strains, and the genome of R61 exhibits extreme levels of evolutionary plasticity with high levels of gene gain and loss. Our results indicate that the multi-drug-resistant strain R61 has evolved three main categories of resistance.Conclusions
Comparative genomic analysis of S. suis strains with diverse drug-resistant phenotypes provided evidence that horizontal gene transfer is an important evolutionary force in shaping the genome of multi-drug-resistant strain R61. In this study, we discovered novel and previously unexamined mutations that are strong candidates for conferring drug resistance. We believe that these mutations will provide crucial clues for designing new drugs against this pathogen. In addition, our work provides a clear demonstration that the use of drugs has driven the emergence of the multi-drug-resistant strain R61. 相似文献15.
16.
Katharina Hoelzle Simone Peter Michele Sidler Manuela M Kramer Max M Wittenbrink Kathrin M Felder Ludwig E Hoelzle 《BMC microbiology》2010,10(1):194
Background
Mycoplasma suis belongs to a group of highly specialized hemotrophic bacteria that attach to the surface of host erythrocytes. Hemotrophic mycoplasmas are uncultivable and the genomes are not sequenced so far. Therefore, there is a need for the clarification of essential metabolic pathways which could be crucial barriers for the establishment of an in vitro cultivation system for these veterinary significant bacteria. 相似文献17.
Ken-ji Yokoi Shinya Kuzuwa Shu-Ichi Iwasaki Ayanori Yamakawa Akira Taketo Ken-Ichi Kodaira 《Bioscience, biotechnology, and biochemistry》2016,80(6):1238-1242
The aureolysin (Aur) gene of S. warneri M (aurWM) was cloned and sequenced. Analyses of the aurWM-inactivated mutant (S. warneri Mau) suggested that AurWM was probably associated with efficient processing of the PROM protease (homolog of V8/SspA serine protease), whereas considerable amount of mature-PROC protease (homolog of SspB cysteine protease) accumulated without AurWM. Additionally, AurWM appeared to affect biofilm formation in an uncertain suppressive way. 相似文献
18.
Wichgers Schreur PJ van Weeghel C Rebel JM Smits MA van Putten JP Smith HE 《PloS one》2012,7(4):e36281
Background
Streptococcus suis is an important infectious agent for pigs and occasionally for humans. The host innate immune system plays a key role in preventing and eliminating S. suis infections. One important constituent of the innate immune system is the protein lysozyme, which is present in a variety of body fluids and immune cells. Lysozyme acts as a peptidoglycan degrading enzyme causing bacterial lysis. Several pathogens have developed mechanisms to evade lysozyme-mediated killing. In the present study we compared the lysozyme sensitivity of various S. suis isolates and investigated the molecular basis of lysozyme resistance for this pathogen.Results
The lysozyme minimal inhibitory concentrations of a wide panel of S. suis isolates varied between 0.3 to 10 mg/ml. By inactivating the oatA gene in a serotype 2 and a serotype 9 strain, we showed that OatA-mediated peptidoglycan modification partly contributes to lysozyme resistance. Furthermore, inactivation of the murMN operon provided evidence that additional peptidoglycan crosslinking is not involved in lysozyme resistance in S. suis. Besides a targeted approach, we also used an unbiased approach for identifying factors involved in lysozyme resistance. Based on whole genome comparisons of a lysozyme sensitive strain and selected lysozyme resistant derivatives, we detected several single nucleotide polymorphisms (SNPs) that were correlated with the lysozyme resistance trait. Two SNPs caused defects in protein expression of an autolysin and a capsule sugar transferase. Analysis of specific isogenic mutants, confirmed the involvement of autolysin activity and capsule structures in lysozyme resistance of S. suis.Conclusions
This study shows that lysozyme resistance levels are highly variable among S. suis isolates and serotypes. Furthermore, the results show that lysozyme resistance in S. suis can involve different mechanisms including OatA-mediated peptidolycan modification, autolysin activity and capsule production. 相似文献19.
Aloka B Bandara Andrea Contreras Araceli Contreras-Rodriguez Ana M Martins Victor Dobrean Sherry Poff-Reichow Parthiban Rajasekaran Nammalwar Sriranganathan Gerhardt G Schurig Stephen M Boyle 《BMC microbiology》2007,7(1):57
Background
In prokaryotes, the ureases are multi-subunit, nickel-containing enzymes that catalyze the hydrolysis of urea to carbon dioxide and ammonia. The Brucella genomes contain two urease operons designated as ure1 and ure2. We investigated the role of the two Brucella suis urease operons on the infection, intracellular persistence, growth, and resistance to low-pH killing. 相似文献20.
Presence of gastric Helicobacter species in children suffering from gastric disorders in Southern Turkey
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Bahadori Ali De Witte Chloë Agin Mehmet De Bruyckere Sofie Smet Annemieke Tümgör Gökhan Güven Gökmen Tülin Haesebrouck Freddy Köksal Fatih 《Helicobacter》2018,23(5)