Studies on Metabolism of Pyrrolidone Carboxylic Acid in Bacteria

Abstract

Formation of l-glutamic acid from pyrrolidone carboxylic acid (PCA) was investigated with using Pseudomonas alcaligenes ATCC-12815. This strain could grow in the medium containing dl-PCA1) as a sole source of carbon and nitrogen, and it could utilize both d- and l- forms of PCA, forming a large quantity of l-glutamic acid in either case. Addition of some nutrients such as yeast extract and casamino acid was effective for the maximal formation of l-glutamic acid. Majority (90%) of the added dl-PCA was converted to l-glutamic acid in the medium containing 2% dl-PCA and 0.05% yeast extract. When PCA-grown cells were incubated with PCA in buffer solution for a short time, l-glutamic acid was also satisfactorily formed. The young cells showed an intensive activity of conversion of PCA to l-glutamate under the aerobic condition and much less one under the anaerobic condition. In proportion to the added amount of glucose given to the precultured PCA medium, the all cells precultured in each medium had respective...