Secreted indole serves as a signal for expression of type III secretion system translocators in enterohaemorrhagic Escherichia coli O157: H7
Secreted indole serves as a signal for expression of type III secretion system translocators in enterohaemorrhagic Escherichia coli O157: H7
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DOI：
10.1099/mic.0.020420-0
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发表时间：
2009-02-01
期刊：
影响因子：
2.8
通讯作者：
Yamaguchi, Akihito
中科院分区：
文献类型：
--
作者：
Hirakawa, Hidetada;Kodama, Toshio;Yamaguchi, Akihito
吲哚是在肠道细菌生长过程中由葡聚糖酶产生的，并在培养基中积累。吲哚产生的生理作用知之甚少。我们发现，肠出血性大肠杆菌（EHEC）O 157：H7与tnaA缺失通过III型分泌系统的EspA和EspB的分泌减少，因此，在HeLa细胞中的附着和消失（A/E）病变的形成减少。添加吲哚恢复和增强EspA和EspB的分泌和形成A/E损伤的tnaA缺失突变EHEC。吲哚除了适度增加LEE 4基因的启动子活性，包括espA和espB，在肠上皮细胞消失的位点。因此，在EHEC中，吲哚可用于信号EspA和EspB表达和分泌，并刺激EHEC在人细胞上形成A/E损伤的能力。
Indole is produced by tryptophanase during growth of enteric bacteria and accumulates in the culture medium. The physiological role of indole production is poorly understood. We discovered that enterohaemorrhagic Escherichia coli (EHEC) O157 : H7 with a tnaA deletion has decreased secretion of EspA and EspB via the type III secretion system and as a result there is reduced formation of attaching and effacing (A/E) lesions in HeLa cells. Addition of indole restored and enhanced secretion of EspA and EspB and formation of A/E lesions by the tnaA deletion mutant EHEC. Indole addition moderately increased the promoter activity of LEE4 genes, including espA and espB, in the locus of enterocyte effacement. Thus in EHEC indole can serve to signal EspA and EspB expression and secretion and stimulate the ability of EHEC to form A/E lesions on human cells.