Transformation of Coiled α-Helices into Cross-β-Sheets Superstructure
Transformation of Coiled α-Helices into Cross-β-Sheets Superstructure
复制标题
DOI：
10.1021/acs.biomac.7b00920
复制
发表时间：
2017-12-01
影响因子：
6.2
通讯作者：
Schaper, Andreas K.
中科院分区：
文献类型：
--
作者：
Yoshioka, Taiyo;Kameda, Tsunenori;Schaper, Andreas K.
由蜜蜂、黄蜂、蚂蚁或大黄蜂产生的纤维丝已知形成四股α螺旋卷曲螺旋超结构。我们已经成功地表明，这种卷曲的线圈结构的形成，不仅在天然纤维，而且在人工薄膜制成的再生丝的黄蜂黄蜂simillima xanthoptera宽角和小角X-射线散射和偏振傅里叶变换红外光谱。基于时间分辨同步同步X射线散射观测原位监测再生丝材料在拉伸变形过程中的结构变化，我们已经表明，在适当的条件下施加张力诱导从卷曲的α-螺旋过渡到交叉β-片层超结构。四股三级超结构在此过程中保持不变。还已经表明，再生丝材料中的无定形蛋白质链转化为具有不同取向的常规β-折叠排列。
The fibrous silk produced by bees, wasps, ants, or hornets is known to form a four-strand alpha-helical coiled coil superstructure. We have succeeded in showing the formation of this coiled coil structure not only in natural fibers, but also in artificial films made of regenerated silk of the hornet Vespa simillima xanthoptera using wide- and small-angle X-ray scatterings and polarized Fourier transform infrared spectroscopy. On the basis of time-resolved simultaneous synchrotron X-ray scattering observations for in situ monitoring of the structural changes in regenerated silk material during tensile deformation, we have shown that the application of tensile force under appropriate conditions induces a transition from the coiled alpha-helices to a cross-beta-sheet superstructure. The four-stranded tertiary superstructure remains unchanged during this process. It has also been shown that the amorphous protein chains in the regenerated silk material are transformed into conventional beta-sheet arrangements with varying orientation.