PlrA (MSMEG_5223) is an essential polar growth regulator in Mycobacterium smegmatis

Mycobacteria expand their cell walls at the cell poles in a manner that is not well described at the molecular level. In this study, we identify a new factor, PlrA, involved in restricting peptidoglycan metabolism to the cell poles in Mycobacterium smegmatis . We show that PlrA localizes to the pole tips, and we identify its essential domain. We show that depletion of plrA pheno-copies depletion of polar growth factor Wag31, and that PlrA is involved in regulating polar peptidoglycan metabolism and the structure of the Wag31 polar foci.