EzrA coordinates septal organization and nucleoid occlusion in Staphylococcus aureus

EzrA coordinates septal organization in Staphylococcus aureus by coupling nascent peptidoglycan synthesis to septal protein anchoring, and its loss disperses peptidoglycan and elevates surface display.

• Why it matters: How S. aureus restricts septum-focused envelope biogenesis to the dividing crosswall, while also maintaining nucleoid occlusion for chromosome segregation, remains unclear.
• What they did: EzrA null cells were compared with wild-type cells for patterns of nascent peptidoglycan incorporation, teichoic acid synthesis, and surface protein display, alongside colocalization of nascent peptidoglycan with Staphylococcal protein A anchoring sites at the septum.
• The result: In wild-type cells, nascent peptidoglycan and nascent Staphylococcal protein A anchoring sites colocalize at the septum, but this spatial coupling is lost without EzrA; EzrA null cells also show impaired nucleoid occlusion with septal ingression over the chromosome leading to chromosome guillotining.