This family of proteins includes members involved in cellulose biosynthesis such as BcsE proteins found in Salmonella typhimurium. Family members carry a GIL domain on the C-terminal. The GIL domain, for GGDEF I-site like domain, is a c-di-GMP binding domain on the BcsE proteins of enterobacteria. It is not essential for cellulose synthesis but is critical for maximal cellulose production. Cellulose production in enterobacteria is controlled by a two-tiered c-di-GMP-dependent system involving BcsE and the PilZ domain containing glycosyltransferase BcsA. The RxGD motif of the GIL domain is required for c-di-GMP binding [1-5].

1: GIL, a new c-di-GMP-binding protein domain involved in regulation of cellulose synthesis in enterobacteria. Fang X, Ahmad I, Blanka A, Schottkowski M, Cimdins A, Galperin MY, Romling U, Gomelsky M; Mol Microbiol. 2014;93:439-452. PMID:24942809

2: Bacterial cellulose biosynthesis: diversity of operons, subunits, products, and functions. Romling U, Galperin MY; Trends Microbiol. 2015;23:545-557. PMID:26077867

3: Structure and Multitasking of the c-di-GMP-Sensing Cellulose Secretion Regulator BcsE. Zouhir S, Abidi W, Caleechurn M, Krasteva PV; mBio. 2020; [Epub ahead of print] PMID:32788377

4: Phosphoethanolamine cellulose: A naturally produced chemically modified cellulose. Thongsomboon W, Serra DO, Possling A, Hadjineophytou C, Hengge R, Cegelski L; Science. 2018;359:334-338. PMID:29348238

5: Molecular organization of the E. coli cellulose synthase macrocomplex. Acheson JF, Ho R, Goularte NF, Cegelski L, Zimmer J; Nat Struct Mol Biol. 2021;28:310-318. PMID:33712813