Alteration of tryptophan-mediated regulation in Neurospora crassa by indoleglycerol phosphate.
نویسندگان
چکیده
The accumulation of imidazoleglycerol phosphate during growth of Neurospora crassa in the presence of 3-amino-1,2,4-triazole was found to cause derepression of tryptophan synthetase and to inhibit the induction of kynureninase. Accumulation of indoleglycerol phosphate in response to growth in the presence of indole acrylic acid or anthranilic acid was also accompanied by derepressed synthesis of tryptophan synthetase. Enzyme synthesis in mutants (his-7 and trp-4) unable to form these intermediates was not altered under similar conditions. The rate of formation of tryptophan synthetase and kynureninase was found to differ in the presence of tryptophan and indole.
منابع مشابه
Inhibition of aminoacyl-transfer ribonucleic acid synthetases and the regulation of amino acid biosynthetic enzymes in Neurospora crassa.
Growth conditions that result in the accumulation of the tryptophan intermediate indoleglycerol phosphate or of the histidine intermediate imidazoleglycerol phosphate cause mycelia of Neurospora crassa to exhibit an immediate and sustained increase in the differential rate at which the biosynthetic enzymes of the tryptophan, histidine, and arginine pathways are synthesized. These accumulated in...
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Previous studies have implicated indole-3glycerol phosphate as an intermediate in the biosynthesis of tryptophan in Escherichia coli (Yanofsky, 1956a, b) and Neurospora crassa (Yanofsky and Rachmeler, 1958; DeMoss, Imai, and Bonner, 1958; Suskind and Jordan, 1959). It has also been established that this compound is converted to tryptophan by the enzyme tryptophan synthetase in both organisms (D...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 95 5 شماره
صفحات -
تاریخ انتشار 1968