ISSN:
1432-0983
Keywords:
Key wordsAspergillus nidulans
;
Ammonium assimilation
;
Glutamate synthase
;
Gene inactivation
;
Glutamate dehydrogenase
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Mutants of Aspergillus nidulans lacking NADP-glutamate dehydrogenase activity grow more poorly than wild-type strains on ammonium as a sole nitrogen source. The leaky growth of these mutants is indicative of an alternative pathway of ammonium assimilation and glutamate biosynthesis. We have PCR-amplified a portion of the A. nidulans gene encoding glutamate synthase and used this sequence to inactivate the genomic copy. This gene, designated gltA, was found to be dispensable for growth on ammonium in the presence of NADP-glutamate dehydrogenase activity. However, a strain carrying the gltA inactivation together with an NADP-glutamate dehydrogenase structural gene mutation (gdhA) was unable to grow on ammonium or on nitrogen sources metabolized via ammonium. The gltA gene was located to linkage group V of the A. nidulans genetic map.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002940050421
