title: Prevalence of 1-aminocyclopropane-1-carboxylate deaminase in Rhizobium spp.
abstract: This is the first report documenting the presence of 1-aminocyclopropane-1-carboxylate (ACC) deaminase in Rhizobium. This enzyme, previously found in free-living bacteria, yeast and fungi, degrades ACC, the immediate precursor of ethylene in higher plants. Thirteen different rhizobial strains were examined by Southern hybridization, Western blots and ACC deaminase enzyme assay. Five of them tested positive for ACC deaminase. Induction of the expression of ACC deaminase was examined in one of the positively tested strains, Rhizobium leguminosarum bv. viciae 128C53K. This rhizobial ACC deaminase had a trace basal level of expression without ACC, but could be induced by a concentration of ACC as low as 1 microM. The more ACC added to this Rhizobium the higher the expression level of the ACC deaminase.
authors.affiliation: Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Ma
authors.forename: Stepanka B
authors.initials: SB
authors.lastname: Sebestianova
authors.forename: Jiri
authors.initials: J
authors.lastname: Sebestian
authors.forename: Genrich I
authors.initials: GI
authors.lastname: Burd
authors.forename: Frédérique C
authors.initials: FC
authors.lastname: Guinel
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Glick
mesh_terms: D000598:Amino Acids, Cyclic / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D019755:Carbon-Carbon Lyases / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D012231:Rhizobium / Q000201:enzymology*
chemical_list: D000598:Amino Acids, Cyclic; D001426:Bacterial Proteins; C023863:1-aminocyclopropane-1-carboxylic acid; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases