Open AccessCharacterization of DicB by partially masking its potent inhibitory activity of cell division
Author(s) -
Suwen Yang,
Hairun Pei,
Xiaoying Zhang,
Qiang Wei,
Jia Zhu,
Jimin Zheng,
Zongchao Jia
Publication year - 2016
Publication title -
open biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.078
H-Index - 53
ISSN - 2046-2441
DOI - 10.1098/rsob.160082
Subject(s) - biology , inhibitory postsynaptic potential , masking (illustration) , cell division , division (mathematics) , cell , microbiology and biotechnology , genetics , computational biology , neuroscience , arithmetic , art , mathematics , visual arts
DicB, a protein encoded by the Kim (Qin) prophage in Escherichia coli, inhibits cell division through interaction with MinC. Thus far, characterization of DicB has been severely hampered owing to its potent activity which ceases cell division and leads to cell death. In this work, through fusing maltose-binding protein to the N-terminus of DicB (MBP-DicB), we successfully expressed and purified recombinant DicB that enabled in vitro analysis for the first time. More importantly, taking advantage of the reduced inhibitory activity of MBP-DicB, we were able to study its effects on cell growth and morphology. Inhibition of cell growth by MBP-DicB was systematically evaluated using various DicB constructs, and their corresponding effects on cell morphology were also investigated. Our results revealed that the N-terminal segment of DicB plays an essential functional role, in contrast to its C-terminal tail. The N-terminus of DicB is of critical importance as even the first amino acid (following the initial Met) could not be removed, although it could be mutated. This study provides the first glimpse of the molecular determinants underlying DicB's function.