Mutants of Neurospora deficient in nicotinamide adenine dinucleotide (phosphate) glycohydrolase.
AUTOR(ES)
Nelson, R E
RESUMO
A new screening technique has been developed for the rapid identification of Neurospora crassa mutants that are deficient in nicotinamide adenine dinucleotide glycohydrolase (NADase) and nicotinamide adenine dinucleotide phosphate glycohydrolase (NADPase) activities. Using this procedure, five single-gene mutants were isolated whose singular difference from wild type appeared to be the absence of NAD(P)ase (EC 3.2.2.6). All five mutants were found to be genetically allelic and did not complement in heterocaryons. This gene, nada [NAD(P)ase], was localized in linkage group IV. One of the nada alleles was found to specify an enzyme that was critically temperature sensitive and had altered substrate affinity. Mutations at the nada locus did not affect the genetic program for the expression of NAD(P)ase during cell differentiation, nor did they have a general effect on NAD catabolism. Nada mutations did not have simultaneous effects on other glycohydrolase activities. Tests of dominance (in heterocaryons) and in vitro mixing experiments did not provide evidence that nada mutations alter activators or inhibitors of NAD(P)ase. Thus, the nada gene appears to specify only the structure of N. crassa NAD(P)ase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=246109Documentos Relacionados
- Purification and properties of streptococcal nicotinamide adenine dinucleotide glycohydrolase.
- Pyridine nucleotide cycle of Salmonella typhimurium: in vitro demonstration of nicotinamide adenine dinucleotide glycohydrolase, nicotinamide mononucleotide glycohydrolase, and nicotinamide adenine dinucleotide pyrophosphatase activities.
- Allosteric Transformation of Reduced Nicotinamide Adenine Dinucleotide (Phosphate) Oxidase Induced by Phagocytosis in Human Polymorphonuclear Leukocytes
- Direct selective procedure for isolating Neurospora mutants defective in nicotinamide adenine dinucleotide phosphate-specific glutamate dehydrogenase.
- Coregulation of oxidized nicotinamide adenine dinucleotide (phosphate) transhydrogenase and glutamate dehydrogenase activities in enteric bacteria during nitrogen limitation.