Nitrite toxicity inAspergillus nidulans: Effect of mutation at thenihB gene.

ThenihB gene ofAspergillus nidulans was found to confer sensitivity to elevated concentrations of nitrite, compact morphology and absence of conidiation. ThenihB locus was allocated to linkage group II and was recessive in heterozygous diploids. When thenihB1 mutant was grown on a mixture of nitrite plus NH 4 (+) its sensitivity to nitrite was unchanged. A possible role for this gene in nitrite transport and/or the maintenance of membrane integrity is discussed.