トリメチルアミンオキサイド還元酵素に関する研究-I

Abstract

Generally, the reduction of trimethylamine oxide in fish muscle is believed only due to the bacterial agents, and the trimethylamine level provides the best indication of bacterial deterioration in marine fish muscle. This experiment revealed that relatively large amount of free trimethylamine was contained in the dark muscle of pelagic fish, such as albacore (Germo alalunga (G.)) or frigate-mackerel (Auxis tapeinosoma (Bleeker)), tested immediately after catch and that marked increase in the amount of this amine was observed even under aseptic condition. On the other hand, no appreciable amount of trimethylamine was produced in the white muscle of these fish under the same condition. Trimethylamine oxide, when added to the dark muscle tissue, was reduced to corresponding amine during aseptic incubation, but no reduction occurred when added to the white muscle. Trimethylamine oxide reducing ability was storongy diminished or inhibited when treated with heat or added with dipyridyl or potassium cyanide as inhibitor which is known to have strong inhibitory influence on the enzyme with heavy metal atoms, especially iron. Despite the treatment with heat, a slight reduction was noted in the case of dark muscle; this might be caused by the thermostable and automatic reducing system contained in the tissue. These results obtained suggest the existence of certain biological system somewhat like the trimethylamine oxide-reductase present in certain bacteria.