Impact of Structural Domains of the Heparin Binding Hemagglutinin of Mycobacterium tuberculosis on Function

Among the few well characterized virulence factors of Mycobacterium tuberculosis (Mtb) is the heparin-binding hemagglutinin (HBHA). HBHA is a 21-kDa protein that localizes to the mycobacterial surface where it can interact with host components. Interaction with epithelial cells and components of the extracellular matrix is mediated by the methylated lysine-rich C-terminal domain of the protein. The N-terminal end of HBHA contains a coiled coil motif which is involved in protein oligomerization and bacterial-bacterial aggregation. In this report, we will focus our attention on what is known about the structure of the HBHA protein and the protein function and role in TB pathogenesis.