Purification and properties of a low-molecular-weight α-mannosidase from Cellulomonas sp.

Cellulomonas sp. isolated from soil produces a high level of α-mannosidase (α-mannanase) inductively in culture fluid. The enzyme had two different molecular weight forms, and the properties of the high-molecular-weight form were reported previously (Takegawa, K. et al.: Biochim. Biophys. Acta, 991, 431-437, 1989). The low-molecular-weight α-mannosidase was purified to homogeneity by polyacrylamide gel electrophoresis. The molecular weight of the enzyme was over 150,000 by gel filtration. Unlike the high-molecular-weight form, the low-molecular-weight enzyme readily hydrolyzed α-1,2- and α-1,3-linked mannose chains.