The Gene-Enzyme Relationships of Proline Biosynthesis in Escherichia coli

Abstract
A simple chromatographic procedure was devised to separate .gamma.-glutamyl phosphate reductase and 1-pyrroline-5-carboxylate reductase, allowing the measurement of the former in crude E. coli extracts. Analysis of a number of strains of E. coli demonstrated that gene proA codes for .gamma.-glutamyl phosphate reductase and proB for .gamma.-glutamyl kinase. Introduction of a ColE1 hybrid plasmid containing the proA,B region into a strain with a chromosomal deletion of proA,B led to 3- and 17-fold increases in the specific activities of .gamma.-glutamyl kinase and .gamma.-glutamyl phosphate reductase, respectively.