CozEa and CozEb play overlapping and essential roles in controlling cell division in Staphylococcus aureus Staphylococcus aureus

摘要

Summary Staphylococcus aureus needs to control the position and timing of cell division and cell wall synthesis to maintain its spherical shape. We identified two membrane proteins, named CozEa and CozEb, which together are important for proper cell division inS. aureus . CozEa and CozEb are homologs of the cell elongation regulator CozESpn ofStreptococcus pneumoniae . WhilecozEa andcozEb were not essential individually, the ?cozEa ?cozEb double mutant was lethal. To study the functions ofcozEa andcozEb , we constructed a CRISPR interference (CRISPRi) system forS. aureus , allowing transcriptional knockdown of essential genes. CRISPRi knockdown ofcozEa in the ?cozEb strain (and vice versa) causes cell morphological defects and aberrant nucleoid staining, showing thatcozEa andcozEb have overlapping functions and are important for normal cell division. We found that CozEa and CozEb interact with and possibly influence localization of the cell division protein EzrA. Furthermore, the CozEEzrA interaction is conserved inS. pneumoniae , and cell division is mislocalized incozE Spn depletedS. pneumoniae cells. Together, our results show that CozE proteins mediate control of cell division inS. aureus andS. pneumoniae , likely via interactions with key cell division proteins such as EzrA.