Characterization of the amdR-controlled lamA and lamB genes of Aspergillus nidulans.
Four Aspergillus nidulans genes are known to be under the control of the trans-acting regulatory gene amdR. We describe the isolation and initial characterization of one of these amdR-regulated genes, lamA. The lam locus, however, was found to consist of two divergently transcribed genes, the lamA gene, and a new gene, also under amdR control, which we have designated lamB. Using recombinant DNA techniques we have constructed a strain of A. nidulans lacking a functional lamB gene. Experiments conducted with this strain demonstrate that lamB, like lamA, is involved in utilization of 2-pyrrolidinone in A. nidulans. Metabolism of a related compound, gamma-amino butyric acid (GABA) is not affected. We also provide evidence that the conversion of exogenous 2-pyrrolidinone to endogenous GABA requires a functional lamB gene. The expression of both lamA and lamB is subject to carbon and nitrogen metabolite repression in addition to amdR-mediated induction by omega-amino acids.
Katz
M E
ME
Department of Genetics, University of Melbourne, Parkville, Victoria, Australia.
Hynes
M J
MJ
D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D005796:Genes; D005800:Genes, Fungal; D005809:Genes, Regulator; D011760:Pyrrolidinones / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D011760:Pyrrolidinones; D005680:gamma-Aminobutyric Acid; C028537:2-pyrrolidone