1-Aminocyclopropane-1-carboxylic acid oxidase reaction mechanism and putative post-translational activities of the ACCO protein.

ABSTRACT: 1-Aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACCO) catalyses the final step in ethylene biosynthesis converting ACC to ethylene, cyanide, CO2, dehydroascorbate and water with inputs of Fe(II), ascorbate, bicarbonate (as activators) and oxygen. Cyanide activates ACCO. A 'nest' comprising several positively charged amino acid residues from the C-terminal α-helix 11 along with Lys158 and Arg299 are proposed as binding sites for ascorbate and bicarbonate to coordinately activate the ACCO reaction. The binding sites for ACC, bicarbonate and ascorbic acid for Malus domestica ACCO1 include Arg175, Arg244, Ser246, Lys158, Lys292, Arg299 and Phe300. Glutamate 297, Phe300 and Glu301 in α-helix 11 are also important for the ACCO reaction. Our proposed reaction pathway incorporates cyanide as

SUBMITTER: Dilley DR 

PROVIDER: S-EPMC3828642 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature