Zaitseva Yu V, Lipasova V A, Plyuta V A, Koksharova O A, Demidyuk I V, Kostrov S V, Khmel I A
Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow, Russia, 123182.
Demidov Yaroslavl State University, Sovetskaya Str. 14, Yaroslavl, Russia, 150003.
Folia Microbiol (Praha). 2019 May;64(3):265-272. doi: 10.1007/s12223-018-0657-5. Epub 2018 Oct 25.
The luxS gene is responsible for the synthesis of AI-2 (autoinducer-2), a signaling molecule that participates in quorum sensing regulation in a large number of bacteria. In this work, we investigated which phenotypes are regulated by luxS gene in Serratia proteamaculans 94, psychrotrophic strain isolated from spoiled refrigerated meat. AI-2 was identified in S. proteamaculans 94, and the luxS gene involved in its synthesis was cloned and sequenced. A mutant with the inactivated luxS gene was constructed. Inactivation of the luxS gene was shown to lead to the absence of AI-2 synthesis, chitinolytic activity, swimming motility, suppression of the growth of fungal plant pathogens Rhizoctonia solani and Helminthosporium sativum by volatile compounds emitted by S. proteamaculans 94 strain, and to a decrease of extracellular proteolytic activity. The knockout of the luxS gene did not affect synthesis of N-acyl-homoserine lactones, lipolytic, and hemolytic activities of S. proteamaculans 94.
luxS基因负责合成AI-2（自诱导物-2），这是一种信号分子，参与大量细菌的群体感应调节。在本研究中，我们调查了luxS基因对粘质沙雷氏菌94（从变质冷藏肉中分离出的嗜冷菌株）哪些表型有调控作用。在粘质沙雷氏菌94中鉴定出了AI-2，并克隆和测序了参与其合成的luxS基因。构建了luxS基因失活的突变体。结果表明，luxS基因失活导致AI-2合成缺失、几丁质酶活性、游动性丧失，粘质沙雷氏菌94菌株释放的挥发性化合物对真菌植物病原菌立枯丝核菌和小麦根腐病菌生长的抑制作用消失，以及细胞外蛋白水解活性降低。luxS基因敲除不影响粘质沙雷氏菌94的N-酰基高丝氨酸内酯合成、脂肪分解和溶血活性。
