Format

Send to

Choose Destination
Sci Rep. 2017 Oct 3;7(1):12583. doi: 10.1038/s41598-017-11241-w.

Impact of fluorescent protein fusions on the bacterial flagellar motor.

Author information

1
Single-molecule Biophysics dept, Centre de Biochimie Stucturale, CNRS UMR5048 UM INSERM U1054, 29 Rue de Navacelles, 34090, Montpellier, France.
2
Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ, Delft, The Netherlands.
3
Single-molecule Biophysics dept, Centre de Biochimie Stucturale, CNRS UMR5048 UM INSERM U1054, 29 Rue de Navacelles, 34090, Montpellier, France. francesco.pedaci@cbs.cnrs.fr.

Abstract

Fluorescent fusion proteins open a direct and unique window onto protein function. However, they also introduce the risk of perturbation of the function of the native protein. Successful applications of fluorescent fusions therefore rely on a careful assessment and minimization of the side effects, but such insight is still lacking for many applications. This is particularly relevant in the study of the internal dynamics of motor proteins, where both the chemical and mechanical reaction coordinates can be affected. Fluorescent proteins fused to the stator of the Bacterial Flagellar Motor (BFM) have previously been used to unveil the motor subunit dynamics. Here we report the effects on single motors of three fluorescent proteins fused to the stators, all of which altered BFM behavior. The torque generated by individual stators was reduced while their stoichiometry remained unaffected. MotB fusions decreased the switching frequency and induced a novel bias-dependent asymmetry in the speed in the two directions. These effects could be mitigated by inserting a linker at the fusion point. These findings provide a quantitative account of the effects of fluorescent fusions to the stator on BFM dynamics and their alleviation- new insights that advance the use of fluorescent fusions to probe the dynamics of protein complexes.

PMID:
28974721
PMCID:
PMC5626733
DOI:
10.1038/s41598-017-11241-w
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center