edoc

Crystal structures of various maltooligosaccharides bound to maltoporin reveal a specific sugar translocation pathway

Dutzler, R. and Wang, Y. F. and Rizkallah, P. and Rosenbusch, J. P. and Schirmer, T.. (1996) Crystal structures of various maltooligosaccharides bound to maltoporin reveal a specific sugar translocation pathway. Structure, Vol. 4, H. 2. pp. 127-134.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A5258277

Downloads: Statistics Overview

Abstract

BACKGROUND: Maltoporin (which is encoded by the lamB gene) facilitates the translocation of maltodextrins across the outer membrane of E. coli. In particular, it is indispensable for the transport of long maltooligosaccharides, as these do not pass through non-specific porins. An understanding of this intriguing capability requires elucidation of the structural basis. RESULTS: The crystal structures of maltoporin in complex with maltose, maltotriose and maltohexaose reveal an extended binding site within the maltoporin channel. The maltooligosaccharides are in apolar van der Waals contact with the 'greasy slide', a hydrophobic path that is composed of aromatic residues and located at the channel lining. At the constriction of the channel the sugars are tightly surrounded by protein side chains and form an extensive hydrogen-bonding network with ionizable amino-acid residues. CONCLUSION: Hydrophobic interactions with the greasy slide guide the sugar into and through the channel constriction. The glucosyl-binding subsites at the channel constriction confer stereospecificity to the channel along with the ability to scavenge substrate at low concentrations.
Faculties and Departments:05 Faculty of Science > Departement Biozentrum > Structural Biology & Biophysics > Structural Biology (Schirmer)
UniBasel Contributors:Schirmer, Tilman
Item Type:Article, refereed
Article Subtype:Research Article
Bibsysno:Link to catalogue
Publisher:Current Biology
ISSN:0969-2126
Note:Publication type according to Uni Basel Research Database: Journal article
Last Modified:22 Mar 2012 14:22
Deposited On:22 Mar 2012 13:31

Repository Staff Only: item control page