跳转至内容
Merck
CN
  • Unbinding molecular recognition force maps of localized single receptor molecules by atomic force microscopy.

Unbinding molecular recognition force maps of localized single receptor molecules by atomic force microscopy.

Chemphyschem : a European journal of chemical physics and physical chemistry (2008-02-26)
Javier Sotres, Anabel Lostao, Linda Wildling, Andreas Ebner, Carlos Gómez-Moreno, Hermann J Gruber, Peter Hinterdorfer, Arturo M Baró
摘要

Atomic force microscopy is a technique capable to study biological recognition processes at the single-molecule level. In this work we operate the AFM in a force-scan based mode, the jumping mode, where simultaneous topographic and tip-sample adhesion maps are acquired. This approach obtains the unbinding force between a well-defined receptor molecule and a ligand attached to the AFM tip. The method is applied to the avidin-biotin system. In contrast with previous data, we obtain laterally resolved adhesion maps of avidin-biotin unbinding forces highly correlated with single avidin molecules in the corresponding topographic map. The scanning rate 250 pixel s(-1) (2 min for a 128 x 128 image) is limited by the hydrodynamic drag force. We are able to build a rupture-force distribution histogram that corresponds to a single defined molecule. Furthermore, we find that due to the motility of the polymer used as spacer to anchor the ligand to the tip, its direction at rupture does not generally coincide with the normal to the tip-sample, this introduces an appreciable error in the measured force.

材料
货号
品牌
产品描述

Sigma-Aldrich
三乙基胺, BioUltra, ≥99.5% (GC)
Sigma-Aldrich
链亲和素 来源于阿维丁链霉菌, recombinant, expressed in E. coli, lyophilized powder
Sigma-Aldrich
IgG 来源于山羊血清, reagent grade, ≥95% (SDS-PAGE), essentially salt-free, lyophilized powder