Purification and Some Properties of Endo-1, 4-[beta]-D-mannanase from a Mud Snail, Pomacea insularus (de Ordigny)

• Published in: Bioscience, biotechnology, and biochemistry Vol. 57; no. 8; p. 1316
• Main Authors: Yamaura, Izumi, Matsumoto, Toshihiko
• Format: Journal Article
• Language: English
• Published: Tokyo Oxford University Press 01.08.1993
• ISSN: 0916-8451; 1347-6947

Endo-1, 4-β-D-mannanase (1, 4-β-D-mannanohydrolase, EC 3.2.1.78) was purified from viscera of a mud snail, Pomacea insularus (de Ordigny). The purified enzyme gave a single protein band in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight of the purified enzyme was estimated to be 44, 000. The amino-terminal sequence was H·Gly-X-Leu-Arg-Arg-Gln-Gly-Thr-Asn-Ile-Val-Asp-Ser-His-Gly-His-Lys-Val-Phe-Leu-Ser-Gly-Ala-Asn-Thr-Ala-Trp-Val-Ala-Tyr-Gly-Tyr-Asp-. The enzyme was stable from pH about 5.0 to about 10.5 and had its maximum activity at pH about 5.5. The purified enzyme produced M2, M3, M4, and M5 from β-1, 4-mannan. Enzyme activity was greatly inhibited by Ag+, Hg2+, Cu2+, and dithiothreitol at 1 mM concentration. In addition, N-bromosuccinimide completely inhibited the enzyme activity.