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About 600 strains of bacteria which can utilize methanol as the sole source of carbon were isolated from natural sources, and their ability to produce amino acids on the medium containing methanol as the sole source of carbon was tested by paper chromatography, by which 3 strains were screened by virtue of their relatively superior amino acid production. These were tentatively identified as follows ; one strain belonged to the genus methylomonas, while the remaining two were members of the genus Hyphomicrobium. Further studies on their growth characteristics were carried out with relation to amino acid production. According to these experiments, the following results were obtained. 1) No vitamin added was effective for the growth enhancement. 2) Optimum initial concentration of methanol was proved to be one per cent (v/v), and no conspicuous effect of feeding methanol on the growth of these bacteria could be observed, provide that the initial methanol concentration was controlled to 1 per cent. 3) Among the nitrogen sources tested, 0.1 per cent of (NH₄)₂SO₄ enabled the best growth. 4) Addition of 0.001 per cent MgSO₄· 7H₂O largely increased the growth of all three strains. Other metal ions tested were either not effective or strongly inhibitory for the growth. 5) Addition of 0.1 per cent each of yeast extract, corn steep liquor, beef extract, and peptone also increased the growth markedly. 6) About 75㎍/㎖ of alanine could be obtained finally after 64 hr culture of Hypm. A on the medium lcontaining 0.1 per cent yeast extract and 1 percent methanol. Approximately 40㎍/㎖ of glutamic acid by Hypm. GA and 43㎍/㎖ of alanine by Milm. A were produced at the same culture conditions.
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