Since FtsZ is structurally similar to eukaryotic tubulin, selective regions of S. aureus FtsZ have been swapped with equivalent regions from tubulin. These mutant FtsZ proteins were analyzed for their interaction with both wildtype FtsZ and FtsA using the yeast two-hybrid assay. Specific regions were identified which abrogated FtsZ-FtsZ binding but unaffected the FtsA-FtsZ interaction. This work will further our understanding of the regions of FtsZ critical for its physiological role.