1af6
From Proteopedia
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| , resolution 2.4Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Gene: | LAMB (Escherichia coli) | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
MALTOPORIN SUCROSE COMPLEX
Overview
Maltoporin (LamB) facilitates the diffusion of maltodextrins across the outer membrane of E. coli. The structural basis for the specificity of the channel is investigated by X-ray structure analysis of maltoporin in complex with the disaccharides sucrose, trehalose, and melibiose. The sucrose complex, determined to 2.4 A resolution, shows that the glucosyl moiety is partly inserted into the channel constriction, while the bulky fructosyl residue appears to be hindered to enter the constriction, thus interfering with its further translocation. One of the glucosyl moieties of trehalose is found in a similar position as the glucosyl moiety of sucrose, whereas melibiose appears disordered when bound to maltoporin. A comparison with the previously reported maltoporin-maltose complex sheds light on the basis for sugar discrimination, and explains the different permeation rates observed for the saccharides.
About this Structure
1AF6 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Channel specificity: structural basis for sugar discrimination and differential flux rates in maltoporin., Wang YF, Dutzler R, Rizkallah PJ, Rosenbusch JP, Schirmer T, J Mol Biol. 1997 Sep 12;272(1):56-63. PMID:9299337
Page seeded by OCA on Sun Mar 30 18:38:56 2008
