[Studies on characterization of glutamine synthetase from Streptomyces lincolnensis]

Glutamine synthetase from Streptomyces lincolnensis was purified to electrophoretic homogeneity. The effects of pH, temperature and metal ions on the purified enzyme were studied, and the substrate specificity of glutamine synthetase were reported. Under the standard biosynthetic assay system, the substrate saturation curves of glutamine synthetase from Streptomyces lincolnensis for ammonia did not agree with the Michaelis-Menten relationship, with either Mn2+ or Mg2+ as divalent cation, and Hill constants not equal to 1. The K(m) values of GS for Glu and ATP were different with different divalent cation.