Format

Send to

Choose Destination
Biophys J. 2014 Jan 7;106(1):145-53. doi: 10.1016/j.bpj.2013.09.059.

Dynamics of the serine chemoreceptor in the Escherichia coli inner membrane: a high-speed single-molecule tracking study.

Author information

1
Department of Physics, Purdue University, West Lafayette, Indiana.
2
Department of Biological Sciences, Purdue University, West Lafayette, Indiana.
3
Department of Biological Sciences, Purdue University, West Lafayette, Indiana. Electronic address: blwanner@purdue.edu.
4
Department of Physics, Purdue University, West Lafayette, Indiana. Electronic address: kpritchie@purdue.edu.

Abstract

We investigated the mobility of the polar localized serine chemoreceptor, Tsr, labeled by the fluorescent protein Venus in the inner membrane of live Escherichia coli cells at observation rates up to 1000 Hz. A fraction (7%) of all Tsr molecules shows free diffusion over the entire cell surface with an average diffusion coefficient of 0.40 ± 0.01 μm(2) s(-1). The remaining molecules were found to be ultimately confined in compartments of size 290 ± 15 nm and showed restricted diffusion at an inner barrier found at 170 ± 10 nm. At the shortest length-scales (<170 nm), all Tsr molecules diffuse equally. Disruption of the cytoskeleton and rounding of the cells resulted in an increase in the mobile fraction of Tsr molecules and a fragmenting of the previously polar cluster of Tsr consistent with a curvature-based mechanism of Tsr cluster maintenance.

PMID:
24411246
PMCID:
PMC3907255
DOI:
10.1016/j.bpj.2013.09.059
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center