Structure and Composition of the Cell Wall of <i>Neurospora crassa</i>

Abstract

The structure and composition of the cell walls of hyphae of Neurospora crassa were investigated by electron microscopy, chemical analysis, and X-ray diffraction both before and after progressive enzymatic degradation by snail gut enzymes, chitinase, and trypsin. The wall consists of two phases: randomly disposed skeletal microfibrils of chitin only and an amorphous matrix which contains both beta-glucans and protein. The protein contains a high percentage of the amides of aspartic and glutamic acid but no hydroxy-proline or cysteine. A portion of this protein is a component of or is associated with a system of pores which is embedded in the matrix of the wall. These pores, 40 to 70 A in outside diameter, sometimes branch and seem to provide a three-dimensional network from one side of the wall to the other. They may be a general system of transport across the walls.