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Publication Abstract from PubMed

Cyclic guanosine 3',5'-monophosphate (cyclic GMP) is a second messenger whose role in bacterial signalling is poorly understood. A genetic screen in the plant pathogen Xanthomonas campestris (Xcc) identified that XC_0250, which encodes a protein with a class III nucleotidyl cyclase domain, is required for cyclic GMP synthesis. Purified XC_0250 was active in cyclic GMP synthesis in vitro. The linked gene XC_0249 encodes a protein with a cyclic mononucleotide-binding (cNMP) domain and a GGDEF diguanylate cyclase domain. The activity of XC_0249 in cyclic di-GMP synthesis was enhanced by addition of cyclic GMP. The isolated cNMP domain of XC_0249 bound cyclic GMP and a structure-function analysis, directed by determination of the crystal structure of the holo-complex, demonstrated the site of cyclic GMP binding that modulates cyclic di-GMP synthesis. Mutation of either XC_0250 or XC_0249 led to a reduced virulence to plants and reduced biofilm formation in vitro. These findings describe a regulatory pathway in which cyclic GMP regulates virulence and biofilm formation through interaction with a novel effector that directly links cyclic GMP and cyclic di-GMP signalling.

A cyclic GMP-dependent signalling pathway regulates bacterial phytopathogenesis.,An SQ, Chin KH, Febrer M, McCarthy Y, Yang JG, Liu CL, Swarbreck D, Rogers J, Maxwell Dow J, Chou SH, Ryan RP EMBO J. 2013 Sep 11;32(18):2430-8. doi: 10.1038/emboj.2013.165. Epub 2013 Jul 23. PMID:23881098^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.