Document Type

Article

Publication Date

7-1-2016

Abstract

© 2016 FEMS. Escherichia coli DedA/Tvp38 family proteins YghB and YqjA are putative membrane transporters with 62% amino acid identity and overlapping functions. An E. coli strain (BC202) with nonpolar ΔyghB and ΔyqjA mutations displays cell-division defects and temperature sensitivity and is sensitive to antibiotics and alkaline pH. In this study, we performed site-directed mutagenesis on conserved, charged amino acids of YqjA and YghB. We discovered two conserved predicted membrane-embedded arginines (R130 and R136) that are critical for function in both proteins as deined by their ability to complement BC202 phenotypes, when expressed from a plasmid. Lysine can substitute for arginine at position R130 indicating a charge dependence at this position, but could not substitute at R136. In light of the established role that arginine plays in the translocation mechanism of numerous membrane transporters, we hypothesize that these amino acids play a role in the transport mechanism of these DedA/Tvp38 family proteins.

Publication Source (Journal or Book title)

FEMS Microbiology Letters

First Page

1

Last Page

8

COinS