Abstract
The mycelium of the wood-rotting fungus,P. ostreatus, contains NAD-dependent glutamate synthase inhibited by azaserine.l-Glutamine andl-glutamate are the most important free amino acids in the mycelium. Feeding of the mycelium with nitrogenous substrates showed thatl-glutamate,l-aspartate andl-alanine are interconnected by way of transaminases. After the inhibition of glutamine synthetase by methionine-S-sulfoximine the synthesis ofl-glutamate was inhibited and the level of all free amino acids decreased. The15N-NMR spectra of mycelia after the addition of15NH4Cl confirmed that the GS/GOGAT is the only pathway of ammonia assimilation inP. ostreatus and NAD-glutamate dehydrogenase should be the deaminating enzyme.
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Rudolfová, J., Mikeš, V. Involvement of the glutamine synthetase/glutamate synthase pathway in ammonia assimilation by the wood-rotting fungusPleurotus ostreatus . Folia Microbiol 42, 577–582 (1997). https://doi.org/10.1007/BF02815469
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DOI: https://doi.org/10.1007/BF02815469