Function
Adapter that links the pilus rod to the base of the tip fibrillum. Regulates the length of the tip fibrillum and joins it to the pilus rod. Pili are polar filaments radiating from the surface of the bacterium to a length of 0.5-1.5 micrometers and numbering 100-300 per cell, and enable bacteria to colonize the epithelium of specific host organs (By similarity).