Protein tracking and detection of protein motion using atomic force microscopy.
AUTOR(ES)
Thomson, N H
RESUMO
Height fluctuations over three different proteins, immunoglobulin G, urease, and microtubules, have been measured using an atomic force microscope (AFM) operating in fluid tapping mode. This was achieved by using a protein-tracking system, where the AFM tip was periodically repositioned above a single protein molecule (or structure) as thermal drifting occurred. Height (z-piezo signal) data were taken in 1 - or 2-s time slices with the tip over the molecule and compared to data taken on the support. The measured fluctuations were consistently higher when the tip was positioned over the protein, as opposed to the support the protein was adsorbed on. Similar measurements over patches of an amphiphile, where the noise was identical to that on the support, suggest that the noise increase is due to some intrinsic property of proteins and is not a result of different tip-sample interactions over soft samples. The orientation of the adsorbed proteins in these preliminary studies was not known; thus it was not possible to make correlations between the observed motion and specific protein structure or protein function beyond noting that the observed height fluctuations were greater for an antibody (anti-bovine IgG) and an enzyme (urease) than for microtubules.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1225219Documentos Relacionados
- Detection and localization of individual antibody-antigen recognition events by atomic force microscopy.
- Imaging ROMK1 inwardly rectifying ATP-sensitive K+ channel protein using atomic force microscopy.
- Theory of electrostatic effects in soft biological interfaces using atomic force microscopy.
- Stretched DNA structures observed with atomic force microscopy.
- Visualization of RNA crystal growth by atomic force microscopy.