title: BIOTIN METABOLISM IN PLANTS.
abstract: Biotin is an essential cofactor for a small number of enzymes involved mainly in the transfer of CO2 during HCO-3-dependent carboxylation reactions. This review highlights progress in plant biotin research by focusing on the four major areas of recent investigation: the structure, enzymology, and localization of two important biotinylated proteins (methylcrotonoyl-CoA carboxylase involved in the catabolism of leucine and noncyclic isoprenoids; acetyl-CoA carboxylase isoforms involved in a number of biosynthetic pathways); the biosynthesis of biotin; the biotinylation of biotin-dependent carboxylases, including the characterization of biotin holocarboxylase synthetase isoforms; and the detailed characterization of a novel, seed-specific biotinylated protein. A central challenge for plant biotin research is to determine in molecular terms how plant cells regulate the flow of biotin to sustain the biotinylation of biotin-dependent carboxylases during biosynthetic reactions.
authors.affiliation: Laboratoire Mixte CNRS/Aventis (UMR 1932), Aventis CropScience, Lyon, France; e-mail: rdouce@cea.fr
authors.forename: Claude
authors.initials: C
authors.lastname: Alban
authors.forename: Dominique
authors.initials: D
authors.lastname: Job
authors.forename: Roland
authors.initials: R
authors.lastname: Douce