Role of MshQ in MSHA pili biosynthesis and biofilm formation of Aeromonas hydrophila.
Role of MshQ in MSHA pili biosynthesis and biofilm formation of Aeromonas hydrophila.
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DOI：
10.4238/2014.october.31.13
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发表时间：
2014-10
期刊：
影响因子：
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通讯作者：
Yingxue Qin;Q. Yan;X. Mao;Z. Chen;Yongquan Su
中科院分区：
文献类型：
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作者：
Yingxue Qin;Q. Yan;X. Mao;Z. Chen;Yongquan Su
病原菌生物膜的形成是目前研究最广泛的课题之一，但对病原菌生物膜在水产养殖中的应用却知之甚少。嗜水气单胞菌是气单胞菌属的代表种，被认为是水产动物的常见病原菌，与多种水产动物疾病有关，并可导致严重的死亡。本研究的目的是：1)证实嗜水气单胞菌能够在非生物底物上形成生物膜，并构建该细菌的生物膜生长曲线；2)鉴定在形成生物膜过程中起关键作用的基因。用结晶紫法绘制了嗜水气单胞菌的生物膜生长曲线，表明该菌的生物膜形成是一个动态过程。接下来，利用微型Tn10转座子诱变系统构建了致病性嗜水气单胞菌B11突变体库。共筛选到861个突变体，其中5个突变体在生物被膜形成方面存在稳定缺陷。对突变体B112的分子分析表明，编码mshq蛋白的开放阅读框架被破坏。对突变株B112和野生型菌株B11的生长、运动和黏附等生物学特性的比较表明，mshq对于嗜水气单胞菌甘露糖敏感血凝素菌毛的生物合成是必需的，并且在嗜水气单胞菌生物膜形成的早期阶段，这些菌毛在嗜水气单胞菌与固体表面的黏附中起着关键作用。
Biofilm formation of pathogen bacterium is currently one of the most widely studied topics; however, little is known regarding pathogen bacteria biofilms in aquaculture. Aeromonas hydrophila is a representative species of the genus Aeromonas, which has been recognized as a common pathogen, is associated with many diseases in aquatic animals, and causes significant mortality. The objectives of this study are i) to confirm that A. hydrophila can form biofilms on abiotic substrates and construct a biofilm growth curve for this bacterium; ii) to identify the genes that play crucial roles in A. hydrophila biofilm formation. The biofilm growth curve of A. hydrophila was constructed using a crystal violet assay, which showed that biofilm formation for this bacterium is a dynamic process. Next, a mutant library of pathogenic A. hydrophila B11 was constructed using the mini-Tn10 transposon mutagenesis system. A total of 861 mutants were screened, and 5 mutants were stably deficient in biofilm formation. Molecular analysis of the mutant B112 revealed that the open reading frame that encodes the protein MshQ was disrupted. Comparison of biological characteristics including growth, motility, and adhesion between the mutant B112 and the wild-type strain B11 suggested that MshQ is necessary for mannose-sensitive hemagglutinin pilus biosynthesis of A. hydrophila, and that these pili play crucial roles in A.hydrophila adherence to a solid surface during the early stages of biofilm formation.