The respiratory complex I in yeast: Isolation of a geneNUO51 coding for the nucleotide-binding subunit of NADH: Ubiquinone oxidoreductase from the obligately aerobic yeastYarrowia lipolytica

We have isolated a geneNUO51 coding for a homologue of the nucleotide-binding subunit of mitochondrial respiratory chain linked NADH:ubiquinone oxidoreductase from the obligately aerobic yeastYarrowia lipolytica. DNA sequencing revealed a 1464 bp open reading frame encoding a protein with predicted molar mass of about 53.7 kDa. The sequence is highly conserved with its counterparts from filamentous fungi and represents the first yeast homologue of the NADH-binding subunit (51 kDa) of the respiratory complex I. In addition, PFGE and Southern hybridization analysis indicate thatNUO51 is a single copy gene in the genome ofY. lipolytica. The expression ofNUO51 by Northern blot analysis was also examined.