魚類肝臓のセリンハイドロキシメチルトランスフェラーゼ

抄録

The enzyme activity which produces formaldehyde from L-serine was found in the liver of several fish species. The enzyme was recognized as serine hydroxymethyltransferase (E. C. 2. 1. 2. 1) which catalyzes the reaction, L-serine + tetrahydrofolate ?? glycine + methylenetetrahydrofolate + H₂0; (methylenetetrahydrofolate then liberates formaldehyde non-enzymatically). The enzyme requires pyridoxal phosphate as an activator. The optimum pH of the mackerel liver enzyme was about 7, and the Km values for L-serine and glycine were estimated to be 5.6 and 3.7 mm, respectively.