Contact-Mode High-Resolution High-Speed Atomic Force Microscopy Movies of the Purple Membrane
AUTOR(ES)
Casuso, Ignacio
FONTE
The Biophysical Society
RESUMO
High-speed atomic force microscopy (HS-AFM) is becoming a reference tool for the study of dynamic biological processes. The spatial and time resolutions of HS-AFM are on the order of nanometers and milliseconds, respectively, and allow structural and functional characterization of biological processes at the single-molecule level. In this work we present contact-mode HS-AFM movies of purple membranes containing two-dimensional arrays of bacteriorhodopsin (bR). In high-resolution movies acquired at a 100 ms frame acquisition time, the substructure on individual bR trimers was visualized. In regions in between different bR arrays, dynamic topographies were observed and interpreted as motion of the bR trimers. Similarly, motion of bR monomers in the vicinity of lattice defects in the purple membrane was observed. Our findings indicate that the bR arrays are in a mobile association-dissociation equilibrium. HS-AFM on membranes provides novel perspectives for analyzing the membrane diffusion processes of nonlabeled molecules.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2749746Documentos Relacionados
- Structural Information, Resolution, and Noise in High-Resolution Atomic Force Microscopy Topographs
- A high-speed atomic force microscope for studying biological macromolecules
- High-speed, random-access fluorescence microscopy: I. High-resolution optical recording with voltage-sensitive dyes and ion indicators.
- Atomic force microscopy produces faithful high-resolution images of protein surfaces in an aqueous environment.
- Carbon nanotube atomic force microscopy tips: Direct growth by chemical vapor deposition and application to high-resolution imaging