Comparison of the gene expression patterns of alcohol dehydrogenase isozymes in the thermotolerant yeast Kluyveromyces marxianus and their physiological functions.
Four genes encoding alcohol dehydrogenase (Adh) isozymes in the thermotolerant yeast Kluyveromyces marxianus, a potent candidate for ethanol production at high temperatures, were investigated. Of these, KmADH3 and KmADH4 were cloned and sequenced, and their deduced amino acid sequences were compared with those of KmAdh1 and KmAdh2 and other Adhs of Kluyveromyces lactis and Saccharomyces cerevisiae. The four KmAdhs had high sequence similarity, though KmAdh3 and KmAdh4 possessed an amino-terminal extension as a mitochondrial targeting sequence, and appear to belong to the zinc-containing Adh family. These results and the results of Southern blot experiments suggest that there are at least four Adh isozymes in K. marxianus, two cytoplasmic enzymes and two mitochondrial enzymes. The expression profile revealed that KmADH genes are differently expressed depending on growth phase and carbon source, suggesting that these highly homologous Adhs play distinctive roles in cells.
Lertwattanasakul
Noppon
N
Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan.
Sootsuwan
Kaewta
K
Limtong
Savitree
S
Thanonkeo
Pornthap
P
Yamada
Mamoru
M
D000426:Alcohol Dehydrogenase / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D015139:Blotting, Southern; D002244:Carbon / Q000378:metabolism; D003001:Cloning, Molecular; D017124:Conserved Sequence; D003593:Cytoplasm / Q000201:enzymology; D000431:Ethanol / Q000032:analysis; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005947:Glucose / Q000032:analysis; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007716:Kluyveromyces / Q000201:enzymology* / Q000235:genetics; D008928:Mitochondria / Q000201:enzymology; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D016385:TATA Box; D013696:Temperature
D007527:Isoenzymes; D000431:Ethanol; D002244:Carbon; D000426:Alcohol Dehydrogenase; D005947:Glucose