... Avda, Salamanca,Spain;2Centro Hispano-Luso de Investigaciones Agrarias, Universidad de Salamanca, Edi®ci o Departamental, Avda, Salamanca,Spain The Phycomyces blakesleeanus wild-type is yellow, ... strain A4 86 complemented carA, carRA and carCmutations. These observations allowed us to discard anypossible a lteration in genes carRA and carC in strain A4 86,in agreement with the data derived ... mutant allele was then namedcarB679.DISCUSSIONBiochemical and genetic analysis demonstrate that strain A4 86 has acquired a leaky mutation in the carB gene,originating the mutant allele carB679....