Histone-like protein H-NS regulates biofilm formation and virulence of Actinobacillus pleuropneumoniae
Histone-like protein H-NS regulates biofilm formation and virulence of Actinobacillus pleuropneumoniae
复制标题
组蛋白样蛋白 H-NS 调节胸膜肺炎放线杆菌的生物膜形成和毒力
DOI：
10.1016/j.micpath.2008.11.005
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发表时间：
2009-03-01
影响因子：
3.8
通讯作者：
Chen, Huanchun
中科院分区：
文献类型：
--
作者：
Dalai, Baolige;Zhou, Rui;Chen, Huanchun
胸膜肺炎放线杆菌是猪传染性胸膜肺炎的病原，是一种在世界范围内造成巨大经济损失的非常重要的猪呼吸道传染病。该病的发病机制尚不完全清楚。生物被膜的形成有助于许多革兰氏阴性细菌的完全毒力。在本研究中，从胸膜肺炎弧菌血清型1的4074株(不形成生物膜的菌株)的转座子诱变突变体库中鉴定出两个生物被膜突变株。反向聚合酶链式反应和测序分析表明，两株突变株中编码组蛋白样核结构蛋白(H-NS)的HNS基因均被微型Tn10转座子失活。进一步的分析表明，当突变菌株的溶血活性和对小鼠的半数致死量与亲本菌株相比时，其毒力减弱。实时定量RT-PCR分析表明，HNS突变体中外毒素基因的下调可能是毒力减弱的部分原因。我们的数据表明，H-NS在调节胸膜肺炎沙门氏菌的生物被膜形成和毒力方面起着重要作用。(C)2008爱思唯尔有限公司。保留所有权利。
Actinobacillus pleuropneumoniae is the causative agent of porcine contagious pleuropneumonia, a very important swine respiratory infectious disease causing great economic losses worldwide. The pathogenesis of this disease is still not completely understood. Biofilm formation contributes to full virulence in many Gram-negative bacterial pathogens. In the present study, two biofilm-producing mutants were identified from the transposon mutagenesis mutant pools of A. pleuropneumoniae strain 4074 of serovar 1 (a non-biofilm forming strain). Inverse PCR and sequencing analysis revealed that the hns gene encoding the histone-like nucleoid structuring protein (H-NS) was inactivated by the mini-Tn10 transposon in both mutant strains. Further analysis revealed that the virulence was attenuated in the mutant strains when their haemolytic activity and 50% lethal doses in mice were compared with the parental strain. Real-time RT-PCR analysis suggested that the down-regulation of the exotoxin genes in the hns mutants may partly contribute to the virulence attenuation. Our data indicate that H-NS plays important roles in regulating biofilm formation and virulence in A. pleuropneumoniae. (c) 2008 Elsevier Ltd. All rights reserved.