Functional analysis of alcS, a gene of the alc cluster in Aspergillus nidulans.
The ethanol utilization pathway (alc system) of Aspergillus nidulans requires two structural genes, alcA and aldA, which encode the two enzymes (alcohol dehydrogenase and aldehyde dehydrogenase, respectively) allowing conversion of ethanol into acetate via acetyldehyde, and a regulatory gene, alcR, encoding the pathway-specific autoregulated transcriptional activator. The alcR and alcA genes are clustered with three other genes that are also positively regulated by alcR, although they are dispensable for growth on ethanol. In this study, we characterized alcS, the most abundantly transcribed of these three genes. alcS is strictly co-regulated with alcA, and encodes a 262-amino acid protein. Sequence comparison with protein databases detected a putative conserved domain that is characteristic of the novel GPR1/FUN34/YaaH membrane protein family. It was shown that the AlcS protein is located in the plasma membrane. Deletion or overexpression of alcS did not result in any obvious phenotype. In particular, AlcS does not appear to be essential for the transport of ethanol, acetaldehyde or acetate. Basic Local Alignment Search Tool analysis against the A. nidulans genome led to the identification of two novel ethanol- and ethylacetate-induced genes encoding other members of the GPR1/FUN34/YaaH family, AN5226 and AN8390.
Institut de Génétique et Microbiologie, CNRS Unité Mixte de Recherche 8621, Université Paris-Sud XI, Centre Scientifique d'Orsay, Bâtiment 360, F-91405 Orsay Cedex, France.
Michel
M
Flipphi
Xavier
X
Robellet
Emmanuel
E
Dequier
Xavier
X
Leschelle
Béatrice
B
Felenbok
Christian
C
Vélot
D000426:Alcohol Dehydrogenase / Q000235:genetics; D000444:Aldehyde Dehydrogenase / Q000235:genetics; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D015152:Blotting, Northern; D002462:Cell Membrane / Q000737:chemistry; D017124:Conserved Sequence; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics*; D017353:Gene Deletion; D018628:Gene Dosage; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D007438:Introns / Q000235:genetics; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames; D012331:RNA, Fungal / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
D004271:DNA, Fungal; D005656:Fungal Proteins; D008565:Membrane Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D000426:Alcohol Dehydrogenase; D000444:Aldehyde Dehydrogenase