Cyclic diguanylic acid and cellulose synthesis in Agrobacterium tumefaciens.
The occurrence of the novel regulatory nucleotide bis(3',5')-cyclic diguanylic acid (c-di-GMP) and its relation to cellulose biogenesis in the plant pathogen Agrobacterium tumefaciens was studied. c-di-GMP was detected in acid extracts of 32P-labeled cells grown in various media, and an enzyme responsible for its formation from GTP was found to be present in cell-free preparations. Cellulose synthesis in vivo was quantitatively assessed with [14C]glucose as a tracer. The organism produced cellulose during growth in the absence of plant cells, and this capacity was retained in resting cells. Synthesis of a cellulosic product from UDP-glucose in vitro with membrane preparations was markedly stimulated by c-di-GMP and its precursor GTP and was further enhanced by Ca2+. The calcium effect was attributed to inhibition of a c-di-GMP-degrading enzyme shown to be present in the cellulose synthase-containing membranes.
Amikam
D
D
Department of Biological Chemistry, Hebrew University of Jerusalem, Israel.
Benziman
M
M
D029681:Arabidopsis Proteins; D002482:Cellulose / Q000096:biosynthesis*; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D005964:Glucosyltransferases / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D007700:Kinetics; D010761:Phosphorus Radioisotopes; D011865:Radioisotope Dilution Technique; D012231:Rhizobium / Q000254:growth & development / Q000378:metabolism*
D029681:Arabidopsis Proteins; D010761:Phosphorus Radioisotopes; C062025:bis(3',5')-cyclic diguanylic acid; D006160:Guanosine Triphosphate; D002482:Cellulose; D005964:Glucosyltransferases; C457769:PRC1 protein, Arabidopsis; C028634:cellulose synthase (UDP-forming); D006152:Cyclic GMP