Screening for amino acid pool mutants of Neurospora and yeasts: replica-printing technique

Suppressors of amino acid uptake mutants of Neurospora.

D E T A I L E D analyses of mutation and recombination in a single gene would be facilitated by a system which permitted the effective selection of mutants from a preponderantly vvild-type population and of rare nonmutants from a population of mutants, There have been many genetic studies of genes controlling nutritional requirements, employing selection to detect rare nonmutants. HOWever, in s...

Mutants of Neurospora deficient in D-amino acid oxidase.

Although many investigations have been carried out on the n-amino acid oxidase since its discovery in 1935 (2)) the metabolic role of this enzyme remains somewhat obscure. It is generally believed, on the basis of indirect evidence, that in animals the enzyme functions in the inversion of exogenous n-amino acids over the pathway n-amino acid --+ Lu-keto acid -+ L-amino acid (3). The first step ...

The L-amino acid oxidase of Neurospora.

In 1944 one of us described a n-amino acid oxidase in extracts of Neurospora crassa (1). Except for slight activity against L-glutamate, no oxidation of L-amino acids was observed. Recently a means for inducing the formation of a soluble L-amino acid oxidase by the mold was reported by Bender, Krebs, and Hor0wit.z (2). This is accomplished by reducing the biotin content of the basal medium (3) ...

Neurospora mutants affecting polyamine-dependent processes and basic amino acid transport mutants resistant to the polyamine inhibitor, alpha-difluoromethylornithine.

Polyamines (spermidine and spermine) are required by living cells, but their functions are poorly understood. Mutants of Neurospora crassa with enhanced or diminished sensitivity to interference with polyamine synthesis, originally selected to study the regulation of the pathway, were found to have unexpected defects. A group of four non-allelic mutations, causing no interference with polyamine...

The amino acid pool in Escherichia coli.