State Key Laboratory of Dairy Biotechnology, Bright Dairy & Food Co. Ltd, Shanghai, 200436 People's Republic of China ; Faculty of Resource and Environmental Engineering, Jiangxi University of Science and Technology, No. 86, Hongqi Ave., Ganzhou, 341000 Jiangxi People's Republic of China.
Faculty of Resource and Environmental Engineering, Jiangxi University of Science and Technology, No. 86, Hongqi Ave., Ganzhou, 341000 Jiangxi People's Republic of China.
Indian J Microbiol. 2014 Sep;54(3):293-301. doi: 10.1007/s12088-014-0456-x. Epub 2014 Feb 14.
Lactobacillus casei has traditionally been recognized as a probiotic, thus needing to survive the industrial production processes and transit through the gastrointestinal tract before providing benefit to human health. The two-component signal transduction system (TCS) plays important roles in sensing and reacting to environmental changes, which consists of a histidine kinase (HK) and a response regulator (RR). In this study we identified HKs and RRs of six sequenced L. casei strains. Ortholog analysis revealed 15 TCS clusters (HK-RR pairs), one orphan HKs and three orphan RRs, of which 12 TCS clusters were common to all six strains, three were absent in one strain. Further classification of the predicted HKs and RRs revealed interesting aspects of their putative functions. Some TCS clusters are involved with the response under the stress of the bile salts, acid, or oxidative, which contribute to survive the difficult journey through the human gastrointestinal tract. Computational predictions of 15 TCSs were verified by PCR experiments. This genomic level study of TCSs should provide valuable insights into the conservation and divergence of TCS proteins in the L. casei strains.
干酪乳杆菌传统上被认为是一种益生菌，因此需要在对人类健康产生有益影响之前，在工业生产过程中存活下来，并通过胃肠道。双组分信号转导系统（TCS）在感应和响应环境变化方面起着重要作用，它由一个组氨酸激酶（HK）和一个响应调节剂（RR）组成。在本研究中，我们鉴定了六种测序的干酪乳杆菌菌株的 HK 和 RR。直系同源分析显示 15 个 TCS 簇（HK-RR 对），一个孤儿 HK 和三个孤儿 RR，其中 12 个 TCS 簇存在于所有六种菌株中，三种在一种菌株中缺失。对预测的 HK 和 RR 的进一步分类揭示了它们潜在功能的有趣方面。一些 TCS 簇参与胆汁盐、酸或氧化应激下的反应，有助于在人类胃肠道的艰难旅程中存活下来。通过 PCR 实验验证了 15 个 TCS 的计算预测。这项 TCS 的基因组水平研究应该为干酪乳杆菌菌株中 TCS 蛋白的保守性和多样性提供有价值的见解。
