Production of L-Glutamic Acid from DL-Hydantoin-5-propionic Acid by Microoganisms Part I

Screening of L-Glutamic Acid-Producing Microorganisms and Some Optimal Conditions for Production of L-Glutamic Acid

Abstract

1) Many strains of microorganisms capable of producing L-glutamic acid from DL-hydan-toin-5-propionic acid were found.
Among these, the active strains were Pseudo-monas dacunhae IAM 1199, Pseudomonas incognita IPR. AHH 38, Pseudomons sp. No. 42 ATCC 15447, Micrococcus subfavus FLUEGE IFO 3026, Aerobacter cloacae T-14, Aeobacter aerogenes T-13, Escherichia intermedia IPR. S-51, Achromobacter pestifer No. 80. ATCC 15445, Achromobocter cycloclastes ATCC 15446, and Bacillus brevis ATCC 8185, and the highest was Bacillus brevis ATCC 8185.
2) It was newly found that these bacteria produced exclusively L-form of glutamic acid from both D- and L-form of hydantoin-5-pro-picnic acid.
3) The optimal condions for producing L-glutamic acid by Bacillus brevis ATCC 8185 were as follows, the reaction pH was 9.0 and the temperature was 42°C. Under these adequate conditions using reaction mixture containing 1.0% of DL-hydantoin-5-propionic acid, intact cells of this strain converted 900 of the DL-acid to L-glutamic acid.
4) Addition of DL-hydantoin-5-propionic acid to the preculture medium is necessary to obtain the highly active cells to produce L-glutamic acid.
5) A pathway of producing L-glutamic acid from D-hydantoin-5-propionic acid was also discussed. The assumptive pathway is D-HPA→_chemicalL-HPA→_enzymaticL-glutamic acid.