Dissipation at the angstrom scale: Probing the surface and interior of an enzyme.
Dissipation at the angstrom scale: Probing the surface and interior of an enzyme.
复制标题
埃级耗散：探测酶的表面和内部。
作者：
Zahrasadat Alavi;G. Zocchi
追求材料科学的方法来理解酶的变形性，我们引入了纳米流变学范式中机械响应函数的阶段的测量。物相测量表明，酶的驱动构象运动是耗散的。这种耗散既来自表面水化层，也来自分子内部，通过检查点突变对力学的影响来探讨。我们还记录了与其四种底物结合时，被检测的鸟苷酸激酶的机制的变化。GMP结合使分子变硬，ATP和ADP结合使其变软，而GDP结合没有明显的机械特征。一个高度活跃的双甘氨酸突变体被发现可能会用专一性来换取速度。酶的整体变形既取决于水化层，也取决于多肽链的动力学。
Pursuing a materials science approach to understanding the deformability of enzymes, we introduce measurements of the phase of the mechanical response function within the nanorheology paradigm. Driven conformational motion of the enzyme is dissipative as characterized by the phase measurements. The dissipation originates both from the surface hydration layer and the interior of the molecule, probed by examining the effect of point mutations on the mechanics. We also document changes in the mechanics of the enzyme examined, guanylate kinase, upon binding its four substrates. GMP binding stiffens the molecule, ATP and ADP binding softens it, while there is no clear mechanical signature of GDP binding. A hyperactive two-Gly mutant is found to possibly trade specificity for speed. Global deformations of enzymes are shown to be dependent on both hydration layer and polypeptide chain dynamics.
影响因子：
15
作者：
Armstrong, Brandon D.;Choi, Jennifer;Lopez, Carlos;Wesener, Darryl A.;Hubbell, Wayne;Cavagnero, Silvia;Han, Songi
通讯作者：
Han, Songi
影响因子：
10.8
作者：
Mock JJ;Hill RT;Tsai YJ;Chilkoti A;Smith DR
通讯作者：
Smith DR