Nakamura K, Watanabe S
J Biochem. 1978 May;83(5):1459-70. doi: 10.1093/oxfordjournals.jbchem.a132056.
Myosin-like protein was obtained from E. coli by extraction with a sucrose solution and by precipitation with rabbit skeletal actin. The preparation of E. coli myosin-like protein looked very similar, in the sodium dodecyl sulfate-gel electrophoretic pattern, to that of rabbit skeletal myosin. The myosin-like protein was able to reversibly bind to rabbit actin. It had the activities of EDTA-, Ca-, and Mg-ATPases. The product in the EDTA-ATPase reaction catalyzed by the myosin-like protein was identified as ADP by ion exchange chromatography. The Mg-ATPase activity of E. coli myosin-like protein was activated by either rabbit actin or E. coli actin-like protein though the activation was much stronger by the latter. However, the myosin-like protein did not exhibit superprecipitation either with rabbit actin or with E. coli actin-like protein. Actin-like protein was also obtained from E. coli by essentially the same procedures as those described for preparation of rabbit skeletal actin. E. coli actin-like protein was capable of activating Mg-ATPase of rabbit myosin, and also of superprecipitation with rabbit myosin. Extraction from both the whole cells and the membrane fraction of E. coli strongly suggested that the myosin-like protein and the actin-like protein are both localized in the membrane fraction rather than in the cytoplasmic fraction.
类肌球蛋白蛋白是通过用蔗糖溶液从大肠杆菌中提取并与兔骨骼肌肌动蛋白沉淀而获得的。在十二烷基硫酸钠-凝胶电泳图谱中，大肠杆菌类肌球蛋白蛋白的制备与兔骨骼肌肌球蛋白的制备看起来非常相似。类肌球蛋白蛋白能够与兔肌动蛋白可逆结合。它具有EDTA-、Ca-和Mg-ATP酶的活性。通过离子交换色谱法鉴定，由类肌球蛋白蛋白催化的EDTA-ATP酶反应中的产物为ADP。大肠杆菌类肌球蛋白蛋白的Mg-ATP酶活性可被兔肌动蛋白或大肠杆菌类肌动蛋白样蛋白激活，尽管后者的激活作用更强。然而，类肌球蛋白蛋白与兔肌动蛋白或大肠杆菌类肌动蛋白样蛋白均未表现出超沉淀现象。类肌动蛋白样蛋白也通过与制备兔骨骼肌肌动蛋白所述基本相同的程序从大肠杆菌中获得。大肠杆菌类肌动蛋白样蛋白能够激活兔肌球蛋白的Mg-ATP酶，也能与兔肌球蛋白发生超沉淀。从大肠杆菌的全细胞和膜组分中提取的结果强烈表明，类肌球蛋白蛋白和类肌动蛋白样蛋白都定位于膜组分而非细胞质组分中。
