title: The genetics and biochemistry of urease in Ustilago violacea.
abstract: Two complementing loci in different linkage groups of the basidiomycete Ustilago violacea are involved in urease activity: a structural one (ure-1) and a second inferred to involve a permease (ure-2) locus. Two types of complementing mutations occur in the structural locus: null activity (ure-la) and obviously reduced activity (ure-1b). The ure-2 mutants lacked urease activity in vivo on the phenol red-urea est medium, but gave extracts with wild-type activity. Extracts from wild-type strains gave one site of urease activity after polyacrylamide gel electrophoresis. A number of ure-1b mutants and activity revertants from ure-1a mutants yielded electrophoretically variant urease sites. The results are discussed in terms of enzyme polymorphism in haploid eukaryotes by one (missense) or two (null, then missense) mutations.
mesh_terms: D001487:Basidiomycota / Q000235:genetics*; D005816:Genetic Complementation Test; D008970:Molecular Weight; D009154:Mutation; D014510:Urease / Q000235:genetics*; D014588:Ustilago / Q000235:genetics*
chemical_list: D014510:Urease