Unique Biochemical Features of the Cytokinetic Protein FtsZ of Mycobacteria

FtsZ, the bacterial cytokinetic protein, a structural homologue of mammalian β-tubulin, is present in bacteria of diverse genera, including mycobacteria. The FtsZ protein of Mycobacterium tuberculosis ( M . tuberculosis FtsZ), the causative agent of tuberculosis, is the most studied among the mycobacterial FtsZ proteins as it is a potential anti-tuberculosis drug target. M . tuberculosis FtsZ possesses many unique biochemical features, which include slow polymerisation kinetics, presence of charged amino acids in the C-terminal domain that interacts with a variety of other cell division proteins, and the presence of specific amino acids at unique locations that makes it distinct from the FtsZ of other mycobacterial species and of other bacterial genera. On the other hand, although the FtsZ of Mycobacterium leprae ( M . leprae FtsZ), the causative agent of leprosy, shows high level of conservation with M . tuberculosis FtsZ, it has biochemical properties that are very differ- ent from those of M . tuberculosis FtsZ due to the difference in specific amino acid residues at critical locations on the protein. The present review focuses on these structural features of M . tuberculosis FtsZ and M . leprae FtsZ, as studied by others and by us, in comparison to those of the FtsZ of other mycobacterial species and of other bacterial genera.