(1) 乳酸からピルビン酸を生成せしめる菌株を検索したところ, Pseudomonas aeruginosa, Ps. cruciviae, Ps. dacumhae, Acetobacter suboxydans, Acet. xylinum, Xanthomonas pruni, Xant. maluacearum等の菌株がぎわめて良好であることを知った.
(2) Pseudomonas aeruginosaによる乳酸からピルビン酸の生成試験では,ペプトン,肉エキスからなる有機培養基ではα-ケトグルタル酸を生成するが,乳酸の添加により著量のピルビン酸(11.8mg/ml)を生成する.
(3) 以上のような乳酸のピルビン酸への転化はPs. aeruginosaの休止細胞を用いても観察された.
(4) Ps. aeruginosaは無機合成培養基においてグルコースからピルビン酸のみを蓄積し,その量は対消費糖30～50%に達する.
(5) 上記合成培養基に阻害剤を添加したところNaF, NaN₃, As₂O₃が糖消費及びピルビン酸蓄積を完全に阻害した.また2, 4-DNPは対照に比較して20%程度のピルビン酸蓄積量を増加させる.
(6) Feを10mg/l合成培養基に添加すれば,ピルビン酸の生成は極度に抑制され,α-ケトグルタル酸の蓄積が顕著に増加する.

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A Hyphomycetes, strain F1, isolated from the excrements of Cettia diphone cantans was found to have the following characteristics on uricase production. 1) This strain was resistant to a high concentration of KCl or NaCl, and the addition of about 4.0% of these salts to the medium gave the maximum uricase production, which the was about two times in dry weight of the pellicle and about 15 times in the amount of enzyme compared to the normal fungal medium containing 0.05% of the salts. 2) The zinc-salt was found to be the only accelerator for the uricase production by this strain after detailed examination of various metal salts. Maximum uricase production was obtained by incubating this strain for 5 days in the medium containing 0.001-0.01 % of ZnSO₄·7H₂O or ZnCl₂, when the amount of the enzyme was increased 3-4 fold compared to the absence of zinc salt.

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The effectiveness of purines and pyrimidines as substrates for the induced production of uricase was studied in F-1 strain of Hyphomycetes, in a medium containing casamino acids, as a good nitrogen source for the growth of this strain. The purines were incorporated into the cells at a relatively early stage of the growth and then the enzyme was induced from all the substrates. No other substrates were found more effective than uric acid. The relationship between the amount of added uric acid and uricase production was examined in the following two cases : (1) The maximum concentration of uric acid in the medium was increased to 0.08% by dissolving uric acid into alkaline solution before adding it into the direct medium. Under this condition, the uricase production increased in proportion to the concentration of uric acid added. (2) The amount of uric acid added in the basal medium was increased to 0.30%, beyond its solubility, and undissolved uric acid precipitated in the bottom of Fernbach's culture vessel. In this experiment, there was no distinct relationship between the amount of uric acid added and uricase production. The precipitated uric acid started to dissolve slowly into the medium during the culture and its concentration in the medium increased markedly during the cultured process. Increase in the solubilizing capacity of the medium to uric acid was also observed as in the basal medium.

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