Candida yeast long chain fatty alcohol oxidase is a c-type haemoprotein and plays an important role in long chain fatty acid metabolism.
The industrial yeasts Candida tropicalis or Candida cloacae are able to grow on a variety of long chain alkanes and fatty acids as the sole carbon source. The complete oxidation of these substrates involves two sequential oxidative pathways: omega-oxidation, comprising the P450 alkane oxidase, a flavin-dependent membrane-bound long chain fatty alcohol oxidase [FAO] and a possible separate aldehyde oxidase [F.M. Dickinson, C. Wadforth, Purification and some properties of alcohol oxidase from alkane-grown Candida tropicalis, Biochem. J. 282 (1992) 325-331], and the beta-oxidation pathway, which utilises acylCoA substrates. We recently purified the membrane-bound long chain fatty alcohol oxidase FAO1 and confirmed it is also a c-type haemoprotein. Multiple isoforms may exist for many of these long chain fatty alcohol oxidases and the in vivo requirements for individual genes with respect to specific substrates are still being elucidated. In vitro reconstitution experiments have demonstrated that in Candida maltosa, the cytochrome P450 52A3 gene product can completely oxidise alkanes to dicarboxylic acids [U. Scheller, T. Zimmer, D. Becher, F. Schauer, W. Schunck, Oxygenation Cascade in Conversion of n-Alkanes to, -Dioic Acids Catalyzed by Cytochrome P450 52A3, J. Biol. Chem. 273 (1998) 32528-32534], potentially obviating requirements for a long chain alcohol oxidase. Here, we directly determine in vivo the role of the long chain alcohol oxidase (FAOT) in C. tropicalis, grown on a variety of substrates, followed by gene deletion. The faot double knockout has no detectable faot activity and is incapable of growth on octadecane, but it grows well on oleic acid, palmitic acid and shorter chain alkanes/fatty acids. A spontaneous mutation[s] may have occurred in the faot double gene knockout of C. tropicalis resulting in its inability to grow on oleic acid and hexadecane. The mutations demonstrate that different pathways of octadecane, hexadecane, oleic acid and palmitic acid utilisation exist in C. tropicalis.
Cheng
Qi
Q
Department of Biological and Biomedical Sciences, University of Durham, South Road, Durham DH1 3LE, UK.
Sanglard
Dominique
D
Vanhanen
Sipo
S
Liu
Huan Ting
HT
Bombelli
Paolo
P
Smith
Alison
A
Slabas
Antoni R
AR
D000429:Alcohol Oxidoreductases / Q000737:chemistry / Q000378:metabolism*; D000473:Alkanes / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D041022:Candida tropicalis / Q000201:enzymology* / Q000235:genetics; D017124:Conserved Sequence; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D006418:Heme / Q000378:metabolism; D006420:Hemeproteins / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D019308:Palmitic Acid; D010957:Plasmids; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D000473:Alkanes; D005230:Fatty Acids, Nonesterified; D005656:Fungal Proteins; D006420:Hemeproteins; D019308:Palmitic Acid; D006418:Heme; D000429:Alcohol Oxidoreductases; C065402:long-chain-alcohol dehydrogenase; C007932:n-hexadecane; C022883:octadecane