Lineage and virulence of Streptococcus suis serotype 2 isolates from North America.
Lineage and virulence of Streptococcus suis serotype 2 isolates from North America.
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DOI：
10.3201/eid1712.110609
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发表时间：
2011-12
影响因子：
11.8
通讯作者：
Gottschalk M
中科院分区：
文献类型：
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作者：
Fittipaldi N;Xu J;Lacouture S;Tharavichitkul P;Osaki M;Sekizaki T;Takamatsu D;Gottschalk M
两种序列类型占主导地位，并且比其他类型的毒力较低。我们对 64 株北美猪链球菌血清型 2 猪分离株进行了多位点序列分型。菌株为序列类型 (ST) 28 (51%)、ST25 (44%) 和 ST1 (5%)。我们确定了 ST 与毒力标记物水溶素 (SLY)、胞壁酶相关蛋白 (MRP) 和细胞外因子 (EF) 表达之间的非随机关联。 srtF 和 srtG 菌毛簇编码的菌毛表达也与 ST 非随机相关。 ST1菌株是SLY+EF+MRP+srtF菌毛+srtG菌毛-。 ST25菌株为SLY−EF−MRP−srtF菌毛−srtG菌毛+，大多数ST28菌株为SLY−MRP+EF−srtF菌毛+srtG菌毛+。 ST28 分离株在小鼠感染模型中被证明基本无毒； ST25 菌株表现出中等毒力，ST1 菌株表现出高毒力。 ST1 是导致全世界人类大部分猪链球菌病的原因。它在北美的存在表明该大陆潜在的人畜共患猪链球菌疫情不容忽视。
Two sequence types predominate and have lower virulence than other types. We performed multilocus sequence typing of 64 North American Streptococcus suis serotype 2 porcine isolates. Strains were sequence type (ST) 28 (51%), ST25 (44%), and ST1 (5%). We identified nonrandom associations between STs and expression of the virulence markers suilysin (SLY), muramidase-relased protein (MRP), and extracellular factor (EF). Expression of pili encoded by the srtF and srtG pilus clusters was also nonrandomly associated with STs. ST1 strains were SLY+ EF+ MRP+ srtF pilus+ srtG pilus−. ST25 strains were SLY− EF− MRP− srtF pilus− srtG pilus+, and most ST28 strains were SLY− MRP+ EF− srtF pilus+ srtG pilus+. ST28 isolates proved essentially nonvirulent in a mouse infection model; ST25 strains showed moderate virulence and ST1 isolates were highly virulent. ST1 is responsible for a high proportion of S. suis disease in humans worldwide. Its presence in North America indicates that potential zoonotic S. suis outbreaks in this continent cannot be disregarded.