Presence of a mannoprotein, MnpAp, in the hyphal cell wall of Aspergillus nidulans

Abstract

The presence of a mannoprotein, MnpAp, in the hyphal cell wall of Aspergillus nidulans was examined by immunogold electron microscopy using a mnpA-null mutant as a negative control. The hyphal cell wall of wild type consisted of two layers—an electron-dense smooth outer layer and an electron-translucent inner layer—while the hyphal cell wall of the mnpA-null mutant had an electron-dense irregular outer layer together with the electron-translucent inner layer. In wild type, MnpAp was present throughout the electron-translucent layer of the hyphal cell wall but was absent from the conidial cell wall. In the mnpA-null mutant, MnpAp was absent from the cell walls of both cell types. These results indicate that MnpAp is present in the hyphal cell wall and that it influences cell wall surface structure.

• Aspergillus nidulans
• cell wall
• immunoelectron microscopy
• mannoprotein
• mnpA

The comments of reviewer, Dr. Donald Natvig, Mycologia associate editor, made this article better than it was. We thank Prof. R.S. Hill for reading of manuscript. This work was supported by Korea Research Foundation Grant (KRF-2000-015-DP0373) to S.S.W. through the Basic Science Research Institute at Chonbuk National University in 2000.