Skip Navigation

Journal of Biochemistry 2005 137(1):87-93; doi:10.1093/jb/mvi008
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Sasaki, A.
Right arrow Articles by Hase, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sasaki, A.
Right arrow Articles by Hase, S.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 2005 The Japanese Biochemical Society

BIOCHEMISTRY

Substrate Specificity and Molecular Cloning of the Lily Endo-ß-Mannosidase Acting on N-Glycan

Akiko Sasaki, Takeshi Ishimizu and Sumihiro Hase*

Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043

Endo-ß-mannosidase, which hydrolyzes the Manß1-4GlcNAc linkage in the trimannosyl core structure of N-glycans, was recently purified to homogeneity from lily (Lilium longiflorum) flowers as a heterotrimer [Ishimizu, T., Sasaki, A., Okutani, S., Maeda, M., Yamagishi, M., and Hase, S. (2004) J. Biol. Chem. 279, 38555–38562]. Here, we describe the substrate specificity of the enzyme and cloning of its cDNA. The purified enzyme hydrolyzed pyridylaminated (PA-) MannMan{alpha}1-6Manß1-4GlcNAcß1-4GlcNAc (n = 0–2) to MannMan{alpha}1-6Man and GlcNAcß1-4GlcNAc-PA. It did not hydrolyze PA-sugar chains containing Man{alpha}1-3Manß and/or Xylß1-2Manß. The best substrate among the PA-sugar chains tested was Man{alpha}1-6Manß1-4GlcNAcß1-4GlcNAc-PA with a Km value of 1.2 mM. However, the enzyme displayed a marked preference for the corresponding glycopeptide, Man{alpha}1-6Manß1-4GlcNAcß1-4GlcNAc-peptide (Km value 75 µM). These results indicate that the substrate recognition by the enzyme involves the peptide portion attached to the N-glycan. Sequence information on the purified enzyme was used to clone the corresponding cDNA. The monocotyledonous lily enzyme (952 amino acids) displays 68% identity to its dicotyledonous (Arabidopsis thaliana) homologue. Our results show that the heterotrimeric enzyme is encoded by a single gene that gives rise to three polypeptides following posttranslational proteolysis. The enzyme is ubiquitously expressed, suggesting that it has a general function such as processing or degrading N-glycans.

* To whom correspondence should be addressed. Tel: +81-6-6850-5380, Fax: +81-6-6850-5383, E-mail: suhase{at}chem.sci.osaka-u.ac.jp


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 J BiochemHome page
T. Ishimizu, C. Hashimoto, R. Takeda, K. Fujii, and S. Hase
A Novel {alpha}1,2-L-Fucosidase Acting on Xyloglucan Oligosaccharides is Associated with Endo- -Mannosidase
J. Biochem., December 1, 2007; 142(6): 721 - 729.
[Abstract] [Full Text] [PDF]

Home page
 J BiochemHome page
T. Ishimizu, C. Hashimoto, R. Kajihara, and S. Hase
A Retaining Endo-{beta}-Mannosidase from a Dicot Plant, Cabbage
J. Biochem., June 1, 2006; 139(6): 1035 - 1043.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.