The primary structure of the leu1+ gene of Schizosaccharomyces pombe.

A DNA fragment which carries the leu1 gene encoding beta-isopropylmalate dehydrogenase in Schizosaccharomyces pombe has been isolated by complementation of an E. coli leuB mutation. This 1.5 kb DNA fragment complements not only the S. pombe leu1 mutation, but also the S. cerevisiae leu2 mutation. The nucleotide sequence of the essential part of the leu1 gene and its flanking regions was determined. This sequence contains an open reading frame of 371 codons, from which a protein having a Mr = 39,732 can be predicted. The deduced amino acid sequence and its codon usage were compared with those of the S. cerevisiae LEU2 protein. The cloned DNA will be a useful marker when transforming S. pombe.