Biophysical characterization of the C-terminal region of FliG, an essential rotor component of the Na+-driven flagellar motor

In this study, using CD spectra, gel filtration chromatography and DSC (differential scanning calorimetry), we characterized the physical properties of the C-terminal domain (G214-Stop) of wild-type (WT) FliG and its non-motile phenotype mutant derivatives (L259Q, L270R and L271P), which were derived from the sodium-driven motor of Vibrio. The CD spectra and gel filtration chromatography revealed a slight difference between the WT and the mutant FliG proteins, but the DSC results suggested a large difference in their stabilities. That structural difference was confirmed by differences in protease sensitivity. Based on these results, we conclude that mutations which confer the non-motile phenotype destabilize the C-terminal domain of FliG.

Source: Journal of Biochemistry - January 29, 2014 Category: Biochemistry Authors: Gohara, M., Kobayashi, S., Abe-Yoshizumi, R., Nonoyama, N., Kojima, S., Asami, Y., Homma, M. Tags: Regular Papers Source Type: research