抄録
It was previously reported that an adenineless mutant of Brevibacterium ammoniagenes was found to accumulate an appreciable amount of IMP. The chemical changes in this fermen-tation showed that hypoxanthine first produced de nova appeared to be resynthesized into IMP by salvage pathway. Subsequent attempts to test hypoxanthine addition to the mutant showed that its supplement to the medium stimulated IMP production appreciably. Inosine and AICA were also found to enhance IMP yields markedly. The role of hypo-xanthine as α precursor was confirmed by a finding that 14C-hypoxanthine added was stoic hiometrically converted to 14C-IMP by the mutant.
Subsequent experiments showed that Br. ammoniagenes ATCC 6872, the parent strain of the mutant, was able to produce IMP, GMP and AMP remarkably from hypoxanthine, guanine and adenine, respectively. Over 10mg/ml of IMP could be obtained from hypo-xanthine on complex medium containing yeast extract.
It is thus concluded that Br. ammoniagenes ATCC 6872 is endowed with a splendid ability to convert purine bases into their ribotides very efficiently.
