|
Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Fisheries Sciences / Faculty of Fisheries Sciences >
Peer-reviewed Journal Articles, etc >
Characterization of a β-D-mannosidase from a marine gastropod, Aplysia kurodai
| Title: | Characterization of a β-D-mannosidase from a marine gastropod, Aplysia kurodai |
| Authors: | Zahura, Umme Afsari Browse this author | | Rahman, Mohammad Matiur Browse this author | | Inoue, Akira Browse this author →KAKEN DB | | Ojima, Takao Browse this author →KAKEN DB |
| Keywords: | Aplysia kurodai | | Gastropod | | β-mannosidase | | β-1,4-mannan | | Mannooligosaccharides |
| Issue Date: | May-2012 |
| Publisher: | Elsevier |
| Journal Title: | Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology |
| Volume: | 162 |
| Issue: | 1-3 |
| Start Page: | 24 |
| End Page: | 33 |
| Publisher DOI: | 10.1016/j.cbpb.2012.02.003 |
| PMID: | 22366551 |
| Abstract: | A β-D-mannosidase (EC 3.2.1.25) with a molecular mass of approximately 100 kDa was purified from the digestive fluid of a marine gastropod Aplysia kurodai by ammonium sulfate fractionation followed by column chromatographies on TOYOPEARL Butyl-650 M, TOYOPEARL DEAE-650 M, and Superdex 200 10/300 GL. This enzyme, named AkMnsd in the present study, showed optimal activities at pH 4.5 and 40℃ and was stable at the acidic pH range from 2.0 to 6.7 and the temperature below 38℃. The Km and Vmax values for AkMnsd determined at pH 6.0 and 30℃ with p-nitrophenyl β-D-mannopyranoside were 0.10 mM and 3.75 μmol/min/mg, respectively. AkMnsd degraded various polymer mannans as well as mannooligosaccharides liberating mannose as a major degradation product. Linear mannan from green alga Codium fragile was completely depolymerized by AkMnsd in the presence of AkMan, an endolytic β-mannanase, which we previously isolated from the same animal (Zahura et al., Comp. Biochem. Physiol. B 157, 137-148 (2010)). A cDNA encoding AkMnsd was amplified from the Aplysia hepatopancreas cDNA by the PCR using degenerated primers designed on the basis of N-terminal and internal amino-acid sequences of AkMnsd. The cloned AkMnsd cDNA consisted of 2985 bp and encoded an amino-acid sequence of 931 residues with the calculated molecular mass of 101970 Da. The deduced sequence of AkMnsd showed 20-43% amino-acid identity to those of glycoside-hydrolase-family 2 (GHF2) β-mannosidases. The catalytically important amino-acid residues determined in GHF2 enzymes were completely conserved in AkMnsd. Thus, AkMnsd is regarded as a new member of GHF2 mannosidase from marine gastropod. |
| Type: | article (author version) |
| URI: | http://hdl.handle.net/2115/49356 |
| Appears in Collections: | 水産科学院・水産科学研究院 (Graduate School of Fisheries Sciences / Faculty of Fisheries Sciences) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 尾島 孝男
|
