Nyitray L, Mócz G, Bálint M
FEBS Lett. 1985 Feb 25;181(2):353-6. doi: 10.1016/0014-5793(85)80291-x.
We have compared the proteolysis pattern of reduced and oxidized myosin rods in which the five pairs of SH-groups were interchain crosslinked by employing CuCl2 or 5,5'-dithiobis-2-nitrobenzoate. In the tryptic digest of oxidized rod three new fragments appeared on SDS-polyacrylamide gel electrophoresis (chain masses of 100, 45, and 25 kDa). Based on the N-terminal sequences of the isolated peptides, it is concluded that oxidation creates a new cleavage site 102 residues away from the N-terminus of the rod, in the vicinity of one of the modified SH-groups (Cys-108). This observation indicates that S-S crosslinking of myosin rod leads to a local unfolding of the coiled-coil structure.
我们比较了还原型和氧化型肌球蛋白杆的蛋白水解模式，其中五对SH基团通过使用氯化铜或5,5'-二硫代双-2-硝基苯甲酸进行链间交联。在氧化型杆的胰蛋白酶消化物中，SDS-聚丙烯酰胺凝胶电泳上出现了三个新片段（链质量分别为100、45和25 kDa）。根据分离肽的N端序列，得出结论：氧化在杆的N端102个残基处产生了一个新的切割位点，靠近其中一个修饰的SH基团（Cys-108）。这一观察结果表明，肌球蛋白杆的S-S交联导致卷曲螺旋结构的局部展开。
