title: Isolation and properties of a beta-alanine transaminaseless mutant of Pseudomonas fluorescens.
abstract: beta-Alanine catabolism in Pseudomonas fluorescens is initiated by the enzyme beta-alanine transaminase. We have isolated mutants which fail to produce this enzyme and thus cannot grow on beta-alanine as the sole nitrogen source. The accumulation of beta-alanine-1-(14)C has been studied in one of these mutants, strain 67, and in the wild type. In the mutant, beta-alanine remains in a stable intracellular pool, whereas in the wild type conversion of beta-alanine to an intermediate, presumably malonate semialdehyde, and to CO(2) can be detected. The membrane transport system for beta-alanine can be conveniently studied in this transaminaseless mutant.
mesh_terms: D000409:Alanine / Q000378:metabolism; D000410:Alanine Transaminase / Q000378:metabolism*; D002245:Carbon Dioxide / Q000096:biosynthesis; D002247:Carbon Isotopes; D002854:Chromatography, Paper; D003124:Colorimetry; D003470:Culture Media; D005827:Genetics, Microbial; D006146:Guanidines; D009153:Mutagens; D009154:Mutation; D009603:Nitroso Compounds; D011549:Pseudomonas / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D013237:Stereoisomerism; D014466:Ultraviolet Rays
chemical_list: D002247:Carbon Isotopes; D003470:Culture Media; D006146:Guanidines; D009153:Mutagens; D009603:Nitroso Compounds; D002245:Carbon Dioxide; D000410:Alanine Transaminase; D000409:Alanine