@article {496,
	title = {Site-specific characterization of the association of xylooligosaccharides with the CBM13 lectin-like xylan binding domain from Streptomyces lividans xylanase 10A by NMR spectroscopy},
	journal = {Biochemistry},
	volume = {41},
	number = {13},
	year = {2002},
	note = {ISI Document Delivery No.: 538ARTimes Cited: 12Cited Reference Count: 53},
	month = {Apr},
	pages = {4255-4263},
	type = {Article},
	abstract = {Endo-beta-1,4-xylanase 10A (Xyn10A) from Streptomyces lividans includes an N-terminal catalytic module and a 130-residue C-terminal family 13 carbohydrate-binding module (CBM13). This latter domain adopts a beta-trefoil structure with three potential binding sites (alpha, beta, and gamma) for a variety of small sugars, xylooligosaccharides, and xylan polymers. To investigate the role of this multivalency in carbohydrate binding, we have used NMR spectroscopy to characterize the interaction of isolated CBM13 with a series of sugars. We have assigned resonances from the main chain nuclei of CBM13 using heteronuclear NMR experiments. Analysis of N-15 NMR relaxation data using the extended model free formalism reveals that CBM13 tumbles as an oblate ellipsoid (D-\/D-perpendicular to = 0.80+/-0.02) and that its backbone is relatively rigid on the sub-nanosecond time scale. In particular, the three binding sites show no distinct patterns of increased internal mobility. Ligand-induced chemical shift changes in the H-1-N-15 HSQC spectra of CBM13 were monitored as a function of increasing concentrations Of L-arabinose, lactose, D-xylose, xylobiose, xylotetraose, and xylohexaose. Patterns of shift perturbations for well-resolved resonances demonstrate that all of these sugars associate independently with the three binding sites of CBM13. On the basis of the site-specific association constants derived from a quantitative analysis of these titration data, we show that L-arabinose, lactose, and D-xylose preferentially bind to the alpha site of CBM13, xylobiose binds equally well to all three sites, and xylotetraose and xylohexaose prefer binding to the beta site. Inspection of the crystallographic structure of CBM13 [Notenboom, V., Boraston, A. B., Williams, S. J., Kilburn, D. G., and Rose, D. R. (2002) Biochemistry 41, 4246-4254] provides a rationalization for these results.},
	keywords = {BACKBONE DYNAMICS, CELLULOMONAS-FIMI CENC, CHEMICAL-SHIFTS, CRYSTAL-STRUCTURES, E-86, IMPROVED SENSITIVITY, INSOLUBLE LIGANDS, LIGAND SPECIFICITY, NUCLEAR-MAGNETIC-RESONANCE, OLIVACEOVIRIDIS, ROTATIONAL DIFFUSION},
	isbn = {0006-2960},
	url = {<Go to ISI>://000174792300010},
	author = {Scharpf, M. and Connelly, G. P. and Lee, G. M. and Boraston, A. B. and Warren, R. A. J. and McIntosh, L. P.}
}
@article {4745,
	title = {Structure and binding specificity of the second N-terminal cellulose-binding domain from Cellulomonas fimi endoglucanase C},
	journal = {Biochemistry},
	volume = {39},
	number = {10},
	year = {2000},
	note = {ISI Document Delivery No.: 294HFTimes Cited: 31Cited Reference Count: 74},
	month = {Mar},
	pages = {2445-2458},
	type = {Article},
	abstract = {The 1,4-beta-glucanase CenC from Cellulomonas fimi contains two cellulose-binding domains, CBDN1 and CBDN2, arranged in tandem at its N-terminus. These homologous CBDs are distinct in their selectivity for binding amorphous and not crystalline cellulose. Multidimensional heteronuclear nuclear magnetic resonance (NMR) spectroscopy was used to determine the tertiary structure of CBDN2 in the presence of saturating amounts of cellopentaose. A total of 1996 experimental restraints were used to calculate an ensemble of 21 final structures for the protein. CBDN2 is composed of 11 beta-strands, folded into two antiparallel beta-sheets, with a topology of a jellyroll beta-sandwich. On the basis of patterns of chemical shift perturbations accompanying the addition of cellooligosaccharides, as well as the observation of intermolecular protein-sugar NOE interactions, the cellulose-binding site of CBDN2 was identified as a cleft that lies across one face of the beta-sandwich. The thermodynamic basis for the binding of cellooligosaccharides was investigated using isothermal titration calorimetry and NMR spectroscopy. Binding is enthalpically driven and consistent with a structural model involving hydrogen bonding between the equatorial hydroxyls of the glucopyranosyl rings and polar amino acid side chains lining the CBDN2 cleft. Affinity electrophoresis was used to determine that CBDN2 also binds soluble beta-1,4-linked polymers of glucose, including hydroxyethylcellulose and beta-1,3-1,4-glucans. This study complements a previous analysis of CBDN1 [Johnson, P. E., Joshi, M. D., Tomme, P., Kilburn, D. G., and McIntosh, L. P. (1996) Biochemistry 35, 14381-14394] and demonstrates that the homologous CBDs from CenC share very similar structures and sugar binding properties.},
	keywords = {3-DIMENSIONAL SOLUTION STRUCTURE, C-13-ENRICHED PROTEINS, C-13-LABELED PROTEINS, CHEMICAL-SHIFT, DISTANCE GEOMETRY, IMPROVED SENSITIVITY, INDEX, ISOTOPICALLY-ENRICHED PROTEINS, LARGER PROTEINS, NUCLEAR-MAGNETIC-RESONANCE, SIDE-CHAIN RESONANCES},
	isbn = {0006-2960},
	url = {<Go to ISI>://000085905300003},
	author = {Brun, E. and Johnson, P. E. and Creagh, A. L. and Tomme, P. and Webster, P. and Haynes, C. A. and McIntosh, L. P.}
}
