期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2009
卷号：106
期号：32
页码：13307-133310
DOI：10.1073/pnas.0902312106
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Mechanical stability of bonds and protein interactions has recently become accessible through single molecule mechanical experiments. So far, mechanical information about molecular bond mechanics has been largely limited to a single direction of force application. However, mechanical force acts as a vector in space and hence mechanical stability should depend on the direction of force application. In skeletal muscle, the giant protein titin is anchored in the Z-disk by telethonin. Much of the structural integrity of the Z-disk hinges upon the titin-telethonin bond. In this paper we show that the complex between the muscle proteins titin and telethonin forms a highly directed molecular bond. It is designed to resist ultra-high forces if they are applied in the direction along which it is loaded under physiological conditions, while it breaks easily along other directions. Highly directed molecular bonds match in an ideal way the requirements of tissues subject to mechanical stress.
关键词：atomic force microscopy ; force spectroscopy ; protein engineering ; protein folding
