HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 280, Issue 27, 25820-25829, July 8, 2005

This Article Full Text Full Text (PDF) All Versions of this Article: 280/27/25820    most recent M501024200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ichinose, H. Articles by Kaneko, S. Search for Related Content PubMed PubMed Citation Articles by Ichinose, H. Articles by Kaneko, S. Social Bookmarking                      What's this?

An Exo--1,3-galactanase Having a Novel -1,3-Galactan-binding Module from Phanerochaete chrysosporium^*

Hitomi Ichinose, Makoto Yoshida, Toshihisa Kotake¶, Atsushi Kuno||, Kiyohiko Igarashi, Yoichi Tsumuraya¶, Masahiro Samejima, Jun Hirabayashi||, Hideyuki Kobayashi, and Satoshi Kaneko**

From the Biological Function Division, National Food Research Institute, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, the Graduate School of Agricultural and Life Sciences, Department of Biomaterials Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, the ^¶Faculty of Science, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570, and the ^||Research Center for Glycoscience, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 6, 1-1-1 Higashi Tsukuba, Ibaraki 305-8566, Japan

An exo--1,3-galactanase gene from Phanerochaete chrysosporium has been cloned, sequenced, and expressed in Pichia pastoris. The complete amino acid sequence of the exo--1,3-galactanase indicated that the enzyme consists of an N-terminal catalytic module with similarity to glycoside hydrolase family 43 and an additional unknown functional domain similar to carbohydrate-binding module family 6 (CBM6) in the C-terminal region. The molecular mass of the recombinant enzyme was estimated as 55 kDa based on SDS-PAGE. The enzyme showed reactivity only toward -1,3-linked galactosyl oligosaccharides and polysaccharide as substrates but did not hydrolyze -1,4-linked galacto-oligosaccharides, -1,6-linked galacto-oligosaccharides, pectic galactan, larch arabinogalactan, arabinan, gum arabic, debranched arabinan, laminarin, soluble birchwood xylan, or soluble oat spelled xylan. The enzyme also did not hydrolyze -1,3-galactosyl galactosaminide, -1,3-galactosyl glucosaminide, or -1,3-galactosyl arabinofuranoside, suggesting that it specifically cleaves the internal -1,3-linkage of two galactosyl residues. High performance liquid chromatographic analysis of the hydrolysis products showed that the enzyme produced galactose from -1,3-galactan in an exo-acting manner. However, no activity toward p-nitrophenyl -galactopyranoside was detected. When incubated with arabinogalactan proteins, the enzyme produced oligosaccharides together with galactose, suggesting that it is able to bypass -1,6-linked galactosyl side chains. The C-terminal CBM6 did not show any affinity for known substrates of CBM6 such as xylan, cellulose, and -1,3-glucan, although it bound -1,3-galactan when analyzed by affinity electrophoresis. Frontal affinity chromatography for the CBM6 moiety using several kinds of terminal galactose-containing oligosaccharides as the analytes clearly indicated that the CBM6 specifically interacted with oligosaccharides containing a -1,3-galactobiose moiety. When the degree of polymerization of galactose oligomers was increased, the binding affinity of the CBM6 showed no marked change.

Received for publication, January 27, 2005 , and in revised form, April 1, 2005.

The nucleotide sequence(s) reported in this paper has been submitted to the DDBJ/GenBank^TM/EBI Data Bank with accession number(s) AB200390.

^* The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

^** To whom correspondence should be addressed. Tel.: 81-29-838-8063; Fax: 81-29-838-7996; E-mail: sakaneko{at}nfri.affrc.go.jp.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				H. Ichinose, T. Kotake, Y. Tsumuraya, and S. Kaneko Characterization of an Endo-{beta}-1,6-Galactanase from Streptomyces avermitilis NBRC14893 Appl. Envir. Microbiol., April 15, 2008; 74(8): 2379 - 2383. [Abstract] [Full Text] [PDF]

				T. Sakamoto, Y. Taniguchi, S. Suzuki, H. Ihara, and H. Kawasaki Characterization of Fusarium oxysporum {beta}-1,6-Galactanase, an Enzyme That Hydrolyzes Larch Wood Arabinogalactan Appl. Envir. Microbiol., May 1, 2007; 73(9): 3109 - 3112. [Abstract] [Full Text] [PDF]

				H. Ichinose, A. Kuno, T. Kotake, M. Yoshida, K. Sakka, J. Hirabayashi, Y. Tsumuraya, and S. Kaneko Characterization of an Exo-{beta}-1,3-Galactanase from Clostridium thermocellum. Appl. Envir. Microbiol., May 1, 2006; 72(5): 3515 - 3523. [Abstract] [Full Text] [PDF]