title: The response of Serratia marcescens JG to environmental changes by quorum sensing system.
abstract: Many bacterial cells are known to regulate their cooperative behaviors and physiological processes through a molecular mechanism called quorum sensing. Quorum sensing in Serratia marcescens JG is mediated by the synthesis of autoinducer 2 (AI-2) which is a furanosyl borate diester. In this study, the response of quorum sensing in S. marcescens JG to environment changes such as the initial pH, carbon sources and boracic acid was investigated by a bioreporter and real-time PCR analysis. The results show that glucose can affect AI-2 synthesis to the greatest extent, and 2.0 % glucose can stimulate S. marcescens JG to produce more AI-2, with a 3.5-fold increase in activity compared with control culture. Furthermore, the response of quorum sensing to changes in glucose concentration was performed by changing the amount of luxS RNA transcripts. A maximum of luxS transcription appeared during the exponential growth phase when the glucose concentration was 20.0 g/L. AI-2 production was also slightly impacted by the low initial pH. It is significant for us that the addition of boracic acid at microdosage (0.1-0.2 g/L) can also induce AI-2 synthesis, which probably demonstrated the feasible fact that the 4,5-dihydroxy-2, 3-pentanedione cyclizes by the addition of borate and the loss of water, is hydrated and is converted to the final AI-2 in S. marcescens JG.
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Shu-Jing
authors.initials: SJ
authors.lastname: Sun
authors.affiliation: Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, People's Republic of China.
authors.forename: Hui-Jun
authors.initials: HJ
authors.lastname: Liu
authors.affiliation: Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, People's Republic of China.
authors.forename: Cai-Hong
authors.initials: CH
authors.lastname: Weng
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Chun-Fen
authors.initials: CF
authors.lastname: Lai
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Liu-Ying
authors.initials: LY
authors.lastname: Ai
authors.affiliation: Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, People's Republic of China.
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Liu
authors.affiliation: Centre for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, People's Republic of China. zhuhu@upc.edu.cn.
authors.forename: Hu
authors.initials: H
authors.lastname: Zhu
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D013437:Carbon-Sulfur Lyases / Q000235:genetics*; D004777:Environment; D015964:Gene Expression Regulation, Bacterial; D006714:Homoserine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D007783:Lactones / Q000378:metabolism*; D053038:Quorum Sensing / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D060888:Real-Time Polymerase Chain Reaction; D012706:Serratia marcescens / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D007783:Lactones; C091088:N-octanoylhomoserine lactone; D012333:RNA, Messenger; D006714:Homoserine; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria
keywords: Autoinducer 2; Environment changes; Quorum sensing; Serratia marcescens; luxS gene