EFFICIENT L-SERINE PRODUCTION FROM METHANOL AND GLYCINE BY RESTING CELLS OF METHYLOBACTERIUM SP STRAIN MN43

Resting cells of methanol-utilizing microorganisms isolated from soils were examined for L-serine production under conditions in which L-ser ine-degradation was suppressed, Strain MN43, a facultative methylotrop hic bacterium identified as a Methylobacterium sp., was selected for f urther studies. Under the optimal conditions, 65 mg/ml L-serine was pr oduced by this bacterium from 50 mg/ml glycine and 104 mg/ml methanol in 5 days, with a molar conversion ratio from glycine to L-serine of 9 3%. This production is the highest so far reported for microbes produc ing L-serine.