Bower S M, Wang Y, Chantler P D
Department of Anatomy and Neurobiology, Medical College of Pennsylvania, Philadelphia 19129.
FEBS Lett. 1992 Sep 28;310(2):132-4. doi: 10.1016/0014-5793(92)81313-b.
The di-thiol reagent, 5,5'-dithiobis (2-nitrobenzoic acid) is shown to induce disulfide bond formation between Mercenaria regulatory light-chain Cys-55 sites on either head of scallop hybrid myosin. This indicates that these two sites on opposite heads of myosin can come within 2A of each other and this confirms a prediction based on earlier data [Chantler, Tao and Stafford (1991) Biophys. J. 59, 1242-1250]. Results demonstrate that myosin heads in solution show a considerable mutual freedom of movement which can be monitored by probes in the vicinity of regulatory light-chain residue 55. Implications for light-chain movement on the myosin head are discussed.
二硫醇试剂5,5'-二硫代双（2-硝基苯甲酸）可诱导扇贝杂交肌球蛋白任一头上的栉孔扇贝调节轻链Cys-55位点之间形成二硫键。这表明肌球蛋白相对的两个头上的这两个位点可以彼此靠近至2埃以内，这证实了基于早期数据的预测[钱特勒、陶和斯塔福德（1991年），《生物物理学杂志》59卷，第1242 - 1250页]。结果表明，溶液中的肌球蛋白头部表现出相当大的相互运动自由度，这可以通过调节轻链残基55附近的探针进行监测。文中还讨论了轻链在肌球蛋白头部运动的影响。
