Ryu Han-Bong, Shin Inji, Yim Hyung-Soon, Kang Sa-Ouk
School of Biological Sciences, Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea.
J Microbiol. 2006 Apr;44(2):206-16.
In this study, we have attempted to characterize the functions of YlaC and YlaD encoded by ylaC and ylaD genes in Bacillus subtilis. The GUS reporter gene, driven by the yla operon promoter, was expressed primarily during the late exponential and early stationary phase, and its expression increased as the result of hydrogen peroxide treatment. Northern and Western blot analyses revealed that the level of ylaC transcripts and YlaC increased as the result of challenge with hydrogen peroxide. A YlaC-overexpressing strain evidenced hydrogen peroxide resistance and a three-fold higher peroxidase activity as compared with a deletion mutant. YlaC-overexpressing and YlaD-disrupted strains evidenced higher sporulation rates than were observed in the YlaC-disrupted and YlaD-overexpressing strains. Analyses of the results of native polyacrylamide gel electrophoresis of recombinant YlaC and YlaD indicated that interaction between YlaC and YlaD was regulated by the redox state of YlaD in vitro. Collectively, the results of this study appear to suggest that YlaC regulated by the YlaD redox state, contribute to oxidative stress resistance in B. subtilis.
在本研究中，我们试图表征枯草芽孢杆菌中由ylaC和ylaD基因编码的YlaC和YlaD的功能。由yla操纵子启动子驱动的GUS报告基因主要在指数后期和稳定期早期表达，并且其表达因过氧化氢处理而增加。Northern印迹和Western印迹分析表明，ylaC转录本和YlaC的水平因过氧化氢刺激而增加。与缺失突变体相比，过表达YlaC的菌株表现出对过氧化氢的抗性，过氧化物酶活性高三倍。过表达YlaC和缺失YlaD的菌株的芽孢形成率高于缺失YlaC和过表达YlaD的菌株。对重组YlaC和YlaD的天然聚丙烯酰胺凝胶电泳结果的分析表明，YlaC和YlaD之间的相互作用在体外受YlaD氧化还原状态的调节。总体而言，本研究结果似乎表明，受YlaD氧化还原状态调节的YlaC有助于枯草芽孢杆菌的氧化应激抗性。
