Electrophoretic analysis of the plasma membrane proteins of a mutant of Neurospora crassa which lacks a cell wall.

The plasma membrane proteins of a mutant of Neurospora crassa (FGSC No. 326) which lacks a cell wall were analyzed by two-dimensional polyacrylamide gel electrophoresis. Approximately 180 different proteins were detected in purified plasma membrane preparations. Nonpermeating labeling experiments indicated that approximately 40% of these proteins were exposed on the extra-cytoplasmic surface of the plasma membranes of these cells. The studies demonstrate the complexity of the protein composition of N. crassa 326 plasma membranes to be greater than has been suggested by previous investigations.