FIG. 6.

Identification of PBPs after denaturing polyacrylamide gel electrophoresis. PBPs were labeled with Flu-ACA or Flu-APA in membranes prepared from vegetative hyphae (Veg) or cells induced to sporulate for 4, 10, or 12 h prior to separation of proteins by denaturing gel electrophoresis. Cells induced to sporulate for 10 h were treated with 100 μM Flu-APA, and then membranes were prepared and proteins were separated as described above. Arrowheads point to PBPs of the indicated molecular masses (in kilodaltons). In the absence of treatment with either Flu–β-lactam, membrane preparations showed two inherently fluorescent proteins of 75 and 30 kDa.