Identification and characterization of a very long-chain fatty acid elongase gene in the methylotrophic yeast, Hansenula polymorpha.
To understand the biosynthetic network of fatty acids in the methylotrophic yeast Hansenula polymorpha, which is able to produce poly-unsaturated fatty acids, we have attempted to identify genes encoding fatty acid elongase. Here we have characterized HpELO1, a fatty acid elongase gene encoding a 319-amino-acid protein containing five predicted membrane-spanning regions that is conserved throughout the yeast Elo protein family. Phylogenetic analysis of the deduced amino acid sequence suggests that HpELO1 is an ortholog of the Saccharomyces cerevisiae ELO3 gene that is involved in the elongation of very long-chain fatty acids (VLCFAs). In the fatty acid profile of the Hpelo1Delta disruptant by gas chromatography/mass spectrometry, the amount of C24:0 and C26:0 decreased to undetectable levels, whereas there was a large accumulation of C22:0, suggesting that the HpELO1 is involved in the elongation of VLCFAs and is essential for the production of C24:0. Expression of HpELO1 suppressed the lethality of the S. cerevisiae elo2Delta elo3Delta double disruptant and recovered the synthesis of VLCFAs. Similar to the S. cerevisiae elo3Delta strain, the Hpelo1Delta disruptant exhibited the extraordinary growth sensitivity to fumonisin B(1), a ceramide synthase inhibitor. Furthermore, cells of the Hpelo1Delta disruptant were more sensitive to Zymolyase and more flocculent than the wild-type cells, clumping together and falling rapidly out of suspension, suggesting that the Hpelo1Delta mutation causes changes in cell wall composition and structure.
Prasitchoke
Phatthanon
P
Osaka University, Department of Biotechnology, Suita, Osaka, Japan.
Kaneko
Yoshinobu
Y
Bamba
Takeshi
T
Fukusaki
Eiichiro
E
Kobayashi
Akio
A
Harashima
Satoshi
S
D000123:Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D002455:Cell Division / Q000187:drug effects / Q000235:genetics; D002473:Cell Wall / Q000737:chemistry / Q000201:enzymology; D002874:Chromosome Mapping; D015825:Chromosomes, Fungal; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology; D000081031:Fatty Acid Elongases; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D037341:Fumonisins / Q000494:pharmacology; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D005816:Genetic Complementation Test; D000432:Methanol / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010843:Pichia / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D004271:DNA, Fungal; D004791:Enzyme Inhibitors; D005227:Fatty Acids; D037341:Fumonisins; D005656:Fungal Proteins; C056933:fumonisin B1; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases; D000432:Methanol