Abstract: A gene coding for aa3 subunit I is obtained from a Corynebacterium glutamicum chromosomal DNA library by hybridization utilizing a probe produced based on a sequence common to a wide range of heme-copper enzymes. A gene coding for subunit II and a gene coding for subunit III are obtained by hybridization using a probe produced by using primers prepared based on the N-terminus amino acid sequence of subunit II, which is determined by using purified cytochrome aa3, and an operon coding for cytochrome bc1 complex existing downstream from the foregoing genes is further obtained.

Abstract: A gene coding for aa3 subunit I is obtained from a Corynebacterium glutamicum chromosomal DNA library by hybridization utilizing a probe produced based on a sequence common to a wide range of heme-copper enzymes. A gene coding for subunit II and a gene coding for subunit III are obtained by hybridization using a probe produced by using primers prepared based on the N-terminus amino acid sequence of subunit II, which is determined by using purified cytochrome aa3, and an operon coding for cytochrome bc1 complex existing downstream from the foregoing genes is further obtained.

Abstract: Oligonucleotides are synthesized based on amino acid sequences of the N-terminus of subunit I, and the N-terminus of subunit II of cytochrome bd type quinol oxidase of Brevibacterium flavum, PCR is performed by using the oligonucleotides as primers, and chromosome DNA of B. flavum as template, and a gene encoding cytochrome bd type quinol oxidase of B. flavum is obtained from a chromosome DNA library of Brevibacterium lactofermentum using the above obtained amplification fragment as a probe.