Process for the microbial production of L-serine using pseudomonas Sp. DSM 672

A process for the production of L-serine in which methanol and glycine are mixed with a submerse culture containing inorganic nutrients and the bacterium Pseudomonas sp. DSM 672 and/or L-Serine accumulating mutants of this bacterium in a reactor supplied with a gas which is air or oxygen-enriched air at a pH in the range 6.0 to 9.0 and at a temperature in the range 20.degree. to 40.degree. C, the mixture is allowed to react, the resulting cell mass is separated from the culture filtrate and the L-serine is isolated from the culture filtrate.