Role of L-threonine deaminase and L-threonine 3-dehydrogenase in the utilization of L-threonine by Pseudomonas aeruginosa.
Mutants of Pseudomonas aeruginosa PAC1 which could grow on L-threonine were isolated. These mutants, like the parent strain, synthesized a biosynthetic threonine deaminase, but its apparent Km value for threonine was higher than that of the enzyme from strain PAC1. These mutants also synthesized an inducible NAD-dependent threonine dehydrogenase, which was not present in the parent strain. No threonine aldolase activity could be detected. The results suggest that the threonine deaminase with lowered affinity for L-threonine, together with L-threonine dehydrogenase, enabled these mutants to utilize L-threonine as the sole source of carbon for growth.
D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*; D013913:Threonine Dehydratase / Q000378:metabolism*
D013912:Threonine; D000429:Alcohol Oxidoreductases; D013913:Threonine Dehydratase