title: Intracellular distribution of fatty alcohol oxidase activity in Mucor circinelloides YR-1 isolated from petroleum contaminated soils.
abstract: In previous studies, Mucor circinelloides YR-1 isolated from petroleum-contaminated soils grown in decane as sole carbon source, showed fatty alcohol oxidase (FAO) activities in either particulate or soluble fractions from a cell-free extract. One is associated to internal membranes (mFAO) and the other one is soluble (sFAO). Both activities appear to be located in the cells in specific compartments other than peroxisomes. Results suggested that mFAO could be located on the inner face of the membrane of these compartments, and sFAO could be in the lumen of the specific compartments. This study reports on the intracellular distribution of FAO activity and the purification of sFAOs and mFAO after several different procedures for release from the membranous fraction using the mixed membrane fraction (MMF) after cellular homogenization as enzymatic source. Results with the purified mFAO show, by molecular weight criteria, that the enzyme has only one type of subunit with molecular mass of 46 kDa, with two isoelectric point components: 6.0 and 6.3. We found that mFAO is strongly associated to the MMF, possibly in a transitory fashion. Using non-denaturating gels, we suggest that sFAO and mFAO have the same subunits in their native structures, and, due to their native molecular weight of approximately 350 kDa, each could be natively structured as an octameric complex.
authors.affiliation: Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Campus Guanajuato, Noria Alta s/n, 36050, Guanajuato, Gto., Mexico.
authors.forename: Hortencia
authors.initials: H
authors.lastname: Silva-Jiménez
authors.forename: Vanesa
authors.initials: V
authors.lastname: Zazueta-Novoa
authors.forename: Arelí
authors.initials: A
authors.lastname: Durón-Castellanos
authors.forename: Carmen
authors.initials: C
authors.lastname: Rodríguez-Robelo
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Leal-Morales
authors.forename: Roberto
authors.initials: R
authors.lastname: Zazueta-Sandoval
mesh_terms: D002462:Cell Membrane / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005233:Fatty Alcohols / Q000378:metabolism*; D015151:Immunoblotting; D007425:Intracellular Membranes / Q000737:chemistry; D007526:Isoelectric Point; D008970:Molecular Weight; D009089:Mucor / Q000737:chemistry* / Q000201:enzymology* / Q000302:isolation & purification; D010088:Oxidoreductases / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D010578:Petroleum; D055503:Protein Multimerization; D021122:Protein Subunits; D012988:Soil Microbiology; D012989:Soil Pollutants
chemical_list: D005233:Fatty Alcohols; D010578:Petroleum; D021122:Protein Subunits; D012989:Soil Pollutants; D010088:Oxidoreductases