Genetic data indicate that proteins containing the GGDEF domain possess diguanylate cyclase activity

A conserved domain, called GGDEF (referring to a conserved central sequence pattern), is detected in many procaryotic proteins, often in various combi nations with putative sensory-regulatory components. Most sequenced bacteri al genomes contain several different GGDEF proteins. The function of this d omain has so far not been experimentally shown. Through genetic complementa tion using genes from three different bacteria encoding proteins with GGDEF domains as the only element in common, we present genetic data indicating (a) that the GGDEF domain is responsible for the diguanylate cyclase activi ty of these proteins, and (b) that the activity of cellulose synthase in Rh izobium leguminosarum bv. trifolii and Agrobacterium tumefaciens is regulat ed by cyclic di-GMP as in Acetobacter xylinum. (C) 2001 Federation of Europ ean Microbiological Societies. Published by Elsevier Science B.V. All right s reserved.