THE CHEMICAL COMPOSITION OF THE HYPHAL WALLS OF THE FUNGUS ALLOMYCES

Aronson , Jerome M., and Leonard Machlis . (U. California, Berkeley.) The chemical composition of the hyphal walls of the fungus Allomyees. Amer. Jour. Bot. 46(4): 292–300. Illus. 1959.—The hyphal walls of Allomyces macrogynus were isloated by both alkaline digestion methods and by sonic oscillation. Both types of preparations showed the walls to consist of chitin, glucan, and ash. In addition, the mechanically isolated walls contained a protein fraction, the properties and significance of which were not determined. Hemicellulose-type polysaccharides, pectic substances, ether soluble lipids, and constituents giving rise to 3–0-α-earboxyethyl hexosamine were not found to be present in the walls. The walls of plants grown for 60–70 hr. under the prescribed conditions contain approximately 60% chitin, 15% glucan, 10% ash, and 10% protein intimately associated with the walls. The percentage of wall material in a mycelium, as well as the percentage of chitin in the walls, increases with the chronological age of the mycelium. These percentages were not, however, affected by variations in the composition of the nutrient medium. The chitin in the walls could be hydrolyzed in the presence of chitinase; lysozyme, however, had no detectable effect on the walls.