Chitin-binding Hemagglutinin Associated with Cell Wall of Conidiobolus lamprauges

Abstract

The cell wall of Conidiobolus lamprauges is composed of D-glucosamine, D-glucose and d-mannose in the ratio of 1:1:1. The first sugar originated from chitin and a part of the second sugar came from β-glucan.

Cell wall-associated, chitin-binding hemagglutinin (endo-CLA) was liberated from the cell wall with β-glucanase but not with chitinase, cellulase, protease, sodium chloride, 2-mercaptoethanol, hydrochloric acid, N-acetyl-D-glucosamine or chitooligosaccharides.

Endo-CLA and extracellular CLA (exo-CLA) showed almost the same sugar specificity and immunological properties in the hemagglutination inhibition test and the double immunodiffusion test, respectively.

Endo-CLA was detected in the cell wall before production of β-glucanase by this organism, whereas exo-CLA was produced in the culture filtrate simultaneously with the enzyme.

These results suggest that CLA was liberated from the β-glucan matrix in the cell wall by the action of β-glucanase.