title: Acylation stabilizes a protease-resistant conformation of protoporphyrinogen oxidase, the molecular target of diphenyl ether-type herbicides.
abstract: Protein acylation is an important way in which a number of proteins with a variety of functions are modified. The physiological role of the acylation of cellular proteins is still poorly understood. Covalent binding of fatty acids to nonintegral membrane proteins is thought to produce transient or permanent enhancement of the association of the polypeptide chains with biological membranes. In this paper, we investigate the functional role for the palmitoylation of an atypical membrane-bound protein, yeast protoporphyrinogen oxidase, which is the molecular target of diphenyl ether-type herbicides. Palmitoylation stabilizes an active heat- and protease-resistant conformation of the protein. Palmitoylation of protoporphyrinogen oxidase has been demonstrated to occur in vivo both in yeast cells and in a heterologous bacterial expression system, where it may be inhibited by cerulenin leading to the accumulation of degradation products of the protein. The thiol ester linking palmitoleic acid to the polypeptide chain was shown to be sensitive to hydrolysis by hydroxylamine and also by the widely used serine-protease inhibitor phenylmethylsulfonyl fluoride.
authors.affiliation: Laboratoire d'Ingénierie des Protéines et Contrôle Métabolique, Département de Microbiologie, Institut Jacques-Monod, Unité Mixte de Recherche 7592, Centre National de la Recherche Scientifique, Université Paris 7, Denis-Diderot, France.
authors.forename: S
authors.initials: S
authors.lastname: Arnould
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: J M
authors.initials: JM
authors.lastname: Camadro
mesh_terms: D000215:Acylation; D000595:Amino Acid Sequence; D002569:Cerulenin / Q000494:pharmacology; D002942:Circular Dichroism; D006540:Herbicides / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010647:Phenyl Ethers / Q000494:pharmacology*; D011487:Protein Conformation; D011489:Protein Denaturation; D011499:Protein Processing, Post-Translational; D050768:Protoporphyrinogen Oxidase; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014357:Trypsin / Q000378:metabolism
chemical_list: D006540:Herbicides; D010647:Phenyl Ethers; D011994:Recombinant Proteins; D002569:Cerulenin; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D050768:Protoporphyrinogen Oxidase; D014357:Trypsin