title: GIL, a new c-di-GMP-binding protein domain involved in regulation of cellulose synthesis in enterobacteria.
abstract: In contrast to numerous enzymes involved in c-di-GMP synthesis and degradation in enterobacteria, only a handful of c-di-GMP receptors/effectors have been identified. In search of new c-di-GMP receptors, we screened the Escherichia coli ASKA overexpression gene library using the Differential Radial Capillary Action of Ligand Assay (DRaCALA) with fluorescently and radioisotope-labelled c-di-GMP. We uncovered three new candidate c-di-GMP receptors in E. coli and characterized one of them, BcsE. The bcsE gene is encoded in cellulose synthase operons in representatives of Gammaproteobacteria and Betaproteobacteria. The purified BcsE proteins from E. coli, Salmonella enterica and Klebsiella pneumoniae bind c-di-GMP via the domain of unknown function, DUF2819, which is hereby designated GIL, GGDEF I-site like domain. The RxGD motif of the GIL domain is required for c-di-GMP binding, similar to the c-di-GMP-binding I-site of the diguanylate cyclase GGDEF domain. Thus, GIL is the second protein domain, after PilZ, dedicated to c-di-GMP-binding. We show that in S. enterica, BcsE is not essential for cellulose synthesis but is required for maximal cellulose production, and that c-di-GMP binding is critical for BcsE function. It appears that cellulose production in enterobacteria is controlled by a two-tiered c-di-GMP-dependent system involving BcsE and the PilZ domain containing glycosyltransferase BcsA.
authors.affiliation: Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA.
authors.forename: Xin
authors.initials: X
authors.lastname: Fang
authors.forename: Irfan
authors.initials: I
authors.lastname: Ahmad
authors.forename: Andrea
authors.initials: A
authors.lastname: Blanka
authors.forename: Marco
authors.initials: M
authors.lastname: Schottkowski
authors.forename: Annika
authors.initials: A
authors.lastname: Cimdins
authors.forename: Michael Y
authors.initials: MY
authors.lastname: Galperin
authors.forename: Ute
authors.initials: U
authors.lastname: Römling
authors.forename: Mark
authors.initials: M
authors.lastname: Gomelsky
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002482:Cellulose / Q000096:biosynthesis*; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005964:Glucosyltransferases / Q000235:genetics* / Q000378:metabolism; D016695:Glycosyltransferases / Q000378:metabolism; D007711:Klebsiella pneumoniae / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D009876:Operon; D019761:Phosphorus-Oxygen Lyases / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D012486:Salmonella typhimurium / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C062025:bis(3',5')-cyclic diguanylic acid; D002482:Cellulose; D016695:Glycosyltransferases; D005964:Glucosyltransferases; C478648:cellulose synthase; D019761:Phosphorus-Oxygen Lyases; C060720:diguanylate cyclase; D006152:Cyclic GMP