Temperature-dependent regulation of Yersinia enterocolitica class III flagellar genes
Temperature-dependent regulation of Yersinia enterocolitica class III flagellar genes
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DOI：
10.1046/j.1365-2958.1996.452978.x
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发表时间：
1996-03-01
影响因子：
3.6
通讯作者：
Minnich, SA
中科院分区：
文献类型：
--
作者：
Kapatral, V;Olson, JW;Minnich, SA
温度是小肠结肠炎耶尔森氏菌以及其他两种密切相关的病原体鼠疫耶尔森氏菌和假结核耶尔森氏菌的关键环境线索。小肠结肠炎菌阶段之间的运动和质粒编码的毒力基因表达的变化。为了确定温度如何调节小肠结肠炎耶尔森氏菌的运动性，我们一直在解剖鞭毛调节层次，以确定运动性在哪个水平上被高温（37 ℃）阻断。在这里，我们报告的克隆，DNA序列，和调节的两个主要监管机构的III类鞭毛基因，fliA（西格玛（F））和flgM（反西格玛（F）），和第三个基因，flgN，我们显示是必需的细丝组装。鉴定Y.小肠结肠炎菌fliA和flgM基因是通过两个S.鼠伤寒沙门氏菌和小肠结肠炎耶尔森氏菌突变和DNA序列分析。鼠疫耶尔森编码鞭毛特异性σ因子σ（F）的小肠结肠炎菌fliA基因定位在三个鞭毛蛋白结构基因的紧下游。flgM和flgN基因分别编码抗-of和丝状体装配所需的基因产物，定位在invasin（inv）基因的下游，但在相反（会聚）方向上转录。通过使用北方印迹分析，我们表明，当细胞暴露于37 ℃时，fliA和flgM的转录立即被抑制，与毒力基因诱导的时间一致。鼠伤寒沙门氏菌flgM（-）突变株、Y.小肠结肠炎flgM（-）突变体是完全毒性的。
Temperature is a key environmental cue for Yersinia enterocolitica as well as for the two other closely related pathogens, Yersinia pestis and Yersinia pseudotuberculosis, Between the range of 30 degrees C and 37 degrees C, Y. enterocolitica phase-varies between motility and plasmid-encoded virulence gene expression. To determine how temperature regulates Y.enterocolitica motility, we have been dissecting the flagellar regulatory hierarchy to determine at which level motility is blocked by elevated temperature (37 degrees C). Here we report the cloning, DNA sequences, and regulation of the two main regulators of Class III flagellar genes, fliA (sigma(F)) and flgM (anti-sigma(F)), and a third gene, flgN, which we show is required for filament assembly. Identification of the Y. enterocolitica fliA and flgM genes was accomplished by functional complementation of both S. typhimurium and Y.enterocolitica mutations and by DNA sequence analysis. The Y. enterocolitica fliA gene, encoding the flagellar-specific sigma-factor, sigma(F), maps immediately downstream of the three flagellin structural genes. The flgM and flgN genes, encoding anti-of and a gene product required for filament assembly, respectively, map downstream of the invasin (inv) gene but are transcribed in the opposite (convergent) direction, By using Northern blot analyses we show that transcription of both fliA and flgM is immediately arrested when cells are exposed to 37 degrees C, coincident with the timing of virulence gene induction, Unlike S. typhimurium flgM(-) mutants, Y. enterocolitica flgM(-) mutants are fully virulent.