Ammonia-excreting mutants of Klebsiella pneumoniae with a pleiotropic defect in nitrogen metabolism

作者：Kuczius T; Kleiner D

来源：Archives of Microbiology, 1996, 166(6): 388-393.

DOI：10.1007/BF01682984

• ammonium metabolism
• glnAntrBC
• nitrogenase regulation
• nitrogen control
• ammonia excretion
• amino acid utilization
• Ntr

Enterobacterial mutants defective in the nitrogen control regulatory system (Ntr) generally display a pleiotropic phenotype with regard to expression and regulation of several enzymes and transport systems involved in the assimilation of N sources. This report describes the isolation and characterization of similar pleiotropic mutants of Klebsiella pneumoniae that cannot be complemented by ntt. genes, The strains excreted ammonia, were unable to grow on a number of N sources, and contained low glutamine:2-oxoglutarate amino transferase and normal, but unmodifiable glutamine synthetase activities and a nitrogenase level largely unaffected by ammonium, but still repressible by an amino acid mixture, Genetic studies suggested that this phenotype is due to overexpression of an unknown regulatory protein.

• 出版日期1996-12