Affiliation:
1. The University of Texas Health Science Center at Tyler, Biomedical Research, Tyler, Texas, USA
2. The National High Magnetic Field Lab and the Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
3. Institute of Medical Biology, Polish Academy of Sciences, Lodz, Poland
Abstract
ABSTRACT
Bacterial cell division and cell wall synthesis are highly coordinated processes involving multiple proteins. Here, we show that Rv0008c, a novel small membrane protein from
Mycobacterium tuberculosis
, localizes to the poles and on membranes and shows an overall punctate localization throughout the cell. Furthermore, Rv0008c interacts with two proteins, CrgA and Wag31, implicated in peptidoglycan (PG) synthesis in mycobacteria. Deletion of the Rv0008c homolog in
M. smegmatis
, MSMEG_0023, caused bulged cell poles, formation of rounded cells, and defects in polar localization of Wag31 and cell wall synthesis, with cell wall synthesis measured by the incorporation of the [
14
C]
N
-acetylglucosamine cell wall precursor. The
M. smegmatis
MSMEG_0023
crgA
double mutant strain showed severe defects in growth, viability, cell wall synthesis, cell shape, and the localization of the FtsZ, FtsI, and Wag31 proteins. The double mutant strain also exhibited increased autolytic activity in the presence of detergents. Because CrgA and Wag31 proteins interact with FtsI individually, we believe that regulated cell wall synthesis and cell shape maintenance require the concerted actions of the CrgA, Rv0008c, FtsI, and Wag31 proteins. We propose that, together, CrgA and Rv0008c, renamed CwsA for
c
ell
w
all synthesis and cell
s
hape protein
A
, play crucial roles in septal and polar PG synthesis and help coordinate these processes with the FtsZ-ring assembly in mycobacteria.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology