title: Membrane association of SadC enhances its diguanylate cyclase activity to control exopolysaccharides synthesis and biofilm formation in Pseudomonas aeruginosa.
abstract: Cyclic diguanosine monophosphate (c-di-GMP) is one of the most important bacterial second messengers that controls many bacterial cellular functions including lifestyle switch between plankton and biofilm. Surface attachment defective (SadC) is a diguanylate cyclase (DGC) involved in the biosynthesis of c-di-GMP in Pseudomonas aeruginosa, an opportunistic pathogen that can cause diverse infections. Here we report the crystal structure of GGDEF domain from SadC and the critical role of the trans-membrane (TM) domain of SadC with regard to biofilm formation, exopolysaccharide production and motility. We showed that over-expression of SadC in P. aeruginosa PAO1 totally inhibited swimming motility and significantly enhanced the production of exopolysaccharide Psl. SadC lacking TM domains (SadC300-487) could not localize on cytoplasmic membrane and form cluster, lost the ability to inhibit the swimming and twitching motility, and showed the attenuated activity to promote Psl production despite that SadC300-487was able to catalyze the synthesize of c-di-GMP in vitro and in vivo. The GGDEF domain of SadC has a typical GGDEF structure and the α-helix connected the TM domains with SadC GGDEF domain is essential for SadC to form DGC oligomers. Our data imply that membrane association of SadC promotes its DGC activity by affecting the formation of active DGC oligomers.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.|University of the Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, Shandong, 250100, China.
authors.forename: Cuilan
authors.initials: C
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, Shandong, 250100, China.
authors.forename: Shiheng
authors.initials: S
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, Shandong, 250100, China.
authors.forename: Hengjiang
authors.initials: H
authors.lastname: Cong
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Yihuan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, Shandong, 250100, China. lcgu@sdu.edu.cn.
authors.forename: Lichuan
authors.initials: L
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China. luyanma27@im.ac.cn.
authors.forename: Luyan Z
authors.initials: LZ
authors.lastname: Ma
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D002462:Cell Membrane / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D019761:Phosphorus-Oxygen Lyases / Q000235:genetics / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D011550:Pseudomonas aeruginosa / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D011135:Polysaccharides, Bacterial; D019761:Phosphorus-Oxygen Lyases; C060720:diguanylate cyclase; D006152:Cyclic GMP