Rapid induction of microsomal delta 12(omega 6)-desaturase activity in chilled Acanthamoeba castellanii.
Rapid induction of microsomal delta 12(omega 6)-desaturase activity in chilled Acanthamoeba castellanii.
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快速诱导冷冻棘阿米巴中微粒体 δ 12(omega 6)-去饱和酶活性。
DOI：
10.1042/bj2960183
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Harwood
中科院分区：
文献类型：
--
作者：
A. Jones;D. Lloyd;J. Harwood
将生长培养物从最佳生长温度（30 摄氏度）冷却至 15 摄氏度后，卡氏棘阿米巴中微粒体 δ 12-去饱和酶的活性增加。在从仅经历 10 分钟冷却的生物体中分离的微粒体中可以检测到这种增加。研究了诱导机制。当蛋白质合成在温度变化之前被阻断时，寒冷时活性的增加大大减少。因此，诱导δ12-去饱和酶的主要机制是增加蛋白质合成。在 20°C 下测定时，δ 12-去饱和酶活性高于在 30°C 下测定时的活性，但这些变化并不是由于 20°C 下 O2 溶解度增加所致。发现 δ 12- 去饱和酶的主要底物是 1-酰基-2-油酰磷脂酰胆碱。
The activity of microsomal delta 12-desaturase in Acanthamoeba castellanii was increased after growing cultures were chilled from the optimal growth temperature (30 degrees C) to 15 degrees C. This increase was detectable in microsomes isolated from organisms subjected to only 10 min chilling. The mechanism of induction was investigated. The increase in activity on chilling was greatly reduced when protein synthesis was blocked before the temperature shift. Thus the major mechanism for the induction of delta 12-desaturase is increased protein synthesis. delta 12-Desaturase activity was higher when assayed at 20 degrees C than when assayed at 30 degrees C, but these changes were not due to the increased solubility of O2 at 20 degrees C. The major substrate of delta 12-desaturase was found to be 1-acyl-2-oleoyl phosphatidylcholine.