TABLE 1.
Requirement for the Xcp, Hxc, or Pil system in the assembly of the type II pseudopilus
| Strain genotype | Activation of molecular machinea:
|
XcpT pseudopilus assemblyb | ||
|---|---|---|---|---|
| Xcp | Hxc | Pil | ||
| Wild-type | + | + | + | Yes |
| xcpP-Z | − | + | + | Yes |
| xcpA | − | − | − | No |
| hxcR pilQ | + | − | − | Yes |
| xcpRS pilQ | − | + | − | Yes |
| xcpRS hxcR | − | − | + | Yes |
| xcpRS hxcR pilQ | − | − | − | No |
a
XcpT was overproduced in different strains in which either one, two, or three of the Xcp, Hxc, and Pil systems are inactivated, as indicated by a − (a functional system is indicated by a +).
b
When the three systems were simultaneously defective, no type II pseudopilus could be assembled, whereas the functionality of only one of these systems was sufficient for assembly.