This domain is found Cyclic GMP-AMP synthase from Vibrio cholerae (DncV), a prokaryotic cGAS-like enzyme that synthesises cyclic GMP- AMP (c-GAMP) and stimulates intestinal colonization. DncV adopts a structure and topology that are typical of the nucleotidyltransferase superfamily. It is organised into two domains: an N-terminal domain that contains the catalytic loop (Pfam:PF21654) and a C- terminal helix bundle that consists of eight helices and one pair of anti-parallel beta-sheets (this entry) [1-3].

1: Structure-guided reprogramming of human cGAS dinucleotide linkage specificity. Kranzusch PJ, Lee ASY, Wilson SC, Solovykh MS, Vance RE, Berger JM, Doudna JA; Cell. 2014;158:1011-1021. PMID:25131990

2: Structural biochemistry of a Vibrio cholerae dinucleotide cyclase reveals cyclase activity regulation by folates. Zhu D, Wang L, Shang G, Liu X, Zhu J, Lu D, Wang L, Kan B, Zhang JR, Xiang Y; Mol Cell. 2014;55:931-937. PMID:25201413

3: Structural Basis for the Catalytic Mechanism of DncV, Bacterial Homolog of Cyclic GMP-AMP Synthase. Kato K, Ishii R, Hirano S, Ishitani R, Nureki O; Structure. 2015;23:843-850. PMID:25865248