Mutants resistant to 1, 2, 4-triazolealanine (TRA) or 2-thiazolealanine (TA) were derived from Corynebacterium glutamicum ATCC-13761 by mutagenic treatment with N-methyl-N'-nitro-N-nitrosoguanidine. More than eighty percent of these mutants were found to accumulate a large amount of L-histidine in culture broth. Among these histidine producers, KY-10260 which was selected on TRA-containing agar, was used to investigate the cultural conditions for histidine production. The amount of histidine accumulation reached to a level of 6_??_8mg/ml with a medium containing 15% molasses (as glucose) and 4.5% ammonium sulfate.
According to the similar procedure, some histidine producers were derived from other bacteria, Arthrobacter citreus, Brevibacterium favum, Bacillus megaterium, Bacillus subtilis and Nocardia globerula.
Japan Society for Bioscience, Biotechnology, and Agrochemistry