DivIVA

DivIVA is a conserved protein involved in cell division and chromosome maintenance in many Gram-positive bacteria. It localizes to the cell poles and the division site, where it helps determine where the cell will divide and how chromosomes are organized during growth and sporulation.

DivIVA’s structure and membrane association are central to its function. It is a small coiled-coil protein that forms dimers, with an N-terminal amphipathic helix that anchors it to the cytoplasmic membrane. DivIVA preferentially concentrates at regions of negative membrane curvature, such as the poles and nascent division sites, allowing it to act as a spatial cue for cellular processes.

Functionally, DivIVA interacts with other proteins to regulate division and chromosome dynamics. At the poles, DivIVA recruits the MinJ–MinCD complex, helping to inhibit erroneous polar Z-ring formation and bias division to midcell. It also interacts with RacA to assist the anchoring of the chromosome to the cell poles, a process particularly important during sporulation and chromosome segregation.

DivIVA has several species-specific roles. In Bacillus subtilis, it is central to proper division site selection and chromosome organization. In Corynebacterium and Mycobacterium species, DivIVA homologs (often termed Wag31) coordinate polar growth and cell wall synthesis, coupling peptidoglycan insertion with pole and septum formation.

Evolutionarily, DivIVA and its homologs are widespread among Gram-positive bacteria and can influence cell shape, growth polarity, and development. Mutations in divIVA or its interactors often lead to abnormal cell morphology, misplaced division sites, and defects in sporulation or chromosome segregation.