BIOTECHNOLOGICAL PRODUCTION OF UNNATURAL L-AMINO-ACIDS FROM D,L-5-MONOSUBSTITUTED HYDANTOINS .2. L-ALPHA-NAPHTHYLALANINE AND L-BETA-NAPHTHYLALANINE

Resting cells of Arthrobacter sp. (DSM 3745) with the ability to form L-tryptophan from D,L-5-(3-indolylmethyl)hydantoin were used for the bioconversion of D,L-5-alpha- and D,L-5-beta-naphthylmethylhydantoin (D,L-5-alpha- and D,L-5-beta-NMH) to the corresponding L-amino acids. Under the optimal reaction conditions of pH 9.7 and 40-degrees-C specific productivities of 0.2 (alpha-naphtylalanine) and 0.6 (beta-naphtylalanine) mM amino acid x g cell dry mass-1 x h-1 were obtained in a 0.1 M Na2CO3/NaHCO3-buffer in a stirred bioreactor.