Signature Active Site Architectures Illuminate the Molecular Basis for Ligand Specificity in Family 35 Carbohydrate Binding Module,

Crystal structures of Klebsiella pneumoniae pullulanase (KPP) in complex with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD) and γ-cyclodextrin (γ-CD) were refined at around 1.98–2.59 Å resolution from data collected at SPring-8. In the structures of the complexes obtained with 1 mM α-CD or γ-CD, one molecule of CD was found at carbohydrate-binding module 41 only (CBM41). In the structures of the complexes obtained with 1 mM β-CD or with 10 mM α-CD or γ-CD, two molecules of CD were found at CBM41 and in the active-site cleft, where the hydrophobic residue of Phe746 occupies the inside cavity of the CD rings. In contrast to α-CD and γ-CD, one β-CD molecule was found at the active site only in the presence of 0.1 mM β-CD. These results were coincident with the solution experiments, which showed that β-CD inhibits this enzyme more than a thousand times more potently than α-CD and γ-CD. The strong inhibition of β-CD is caused by the optimized interaction between β-CD and the side chain of Phe746. The increased K i values of the F746A mutant for β-CD supported the importance of Phe746 in the strong interaction of pullulanase with β-CD.

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Deciphering Ligand Specificity of a Clostridium thermocellum Family 35 Carbohydrate Binding Module (CtCBM35) for Gluco- and Galacto- Substituted Mannans and Its Calcium Induced Stability

PLoS ONE ◽

10.1371/journal.pone.0080415 ◽

2013 ◽

Vol 8 (12) ◽

pp. e80415 ◽

Cited By ~ 4

Author(s):

Arabinda Ghosh ◽

Ana Sofia Luís ◽

Joana L. A. Brás ◽

Neeta Pathaw ◽

Nikhil K. Chrungoo ◽

...

Keyword(s):

Clostridium Thermocellum ◽

Carbohydrate Binding ◽

Carbohydrate Binding Module ◽

Ligand Specificity

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Structure of the ectodomain of the electron transporter Rv2874 fromMycobacterium tuberculosisreveals a thioredoxin-like domain combined with a carbohydrate-binding module

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798315021488 ◽

2016 ◽

Vol 72 (1) ◽

pp. 40-48 ◽

Cited By ~ 2

Author(s):

David C. Goldstone ◽

Peter Metcalf ◽

Edward N. Baker

Keyword(s):

Active Site ◽

Family Members ◽

Thioredoxin Reductase ◽

Cellular Membrane ◽

Integral Membrane Proteins ◽

Carbohydrate Binding ◽

Carbohydrate Binding Module ◽

Active Site Motif ◽

Carbohydrate Binding Site ◽

Reducing Potential

The members of the CcdA family are integral membrane proteins that use a disulfide cascade to transport electrons from the thioredoxin–thioredoxin reductase system in the interior of the cell into the extracytoplasmic space. The core transmembrane portion of this family is often elaborated with additional hydrophilic domains that act as adapters to deliver reducing potential to targets outside the cellular membrane. To investigate the function of family members inMycobacterium tuberculosis, the structure of the C-terminal ectodomain from Rv2874, one of three CcdA-family members present in the genome, was determined. The crystal structure, which was refined at 1.9 Å resolution withR= 0.195 andRfree= 0.219, reveals the predicted thioredoxin-like domain with its conserved Cys-X-X-Cys active-site motif. Unexpectedly, this domain is combined with a second domain with a carbohydrate-binding module (CBM) fold, this being the first reported example of a CBM in association with a thioredoxin-like domain fold. A cavity in the CBM adjacent to the thioredoxin active site suggests a likely carbohydrate-binding site, representing a broadening of the substrate range for CcdA-family members and an expansion of the thioredoxin-domain functionality to carbohydrate modification.

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The molecular basis of ligand specificity of the elephant progestin receptor

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-2007-972478 ◽

2007 ◽

Vol 115 (S 1) ◽

Author(s):

M Wierer ◽

SE Ulbrich ◽

HHD Meyer

Keyword(s):

Molecular Basis ◽

Ligand Specificity ◽

Progestin Receptor

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O-glycosylation effects on family 1 carbohydrate-binding module solution structures

FEBS Journal ◽

10.1111/febs.13500 ◽

2015 ◽

Vol 282 (22) ◽

pp. 4341-4356 ◽

Cited By ~ 13

Author(s):

Renee M. Happs ◽

Xiaoyang Guan ◽

Michael G. Resch ◽

Mark F. Davis ◽

Gregg T. Beckham ◽

...

Keyword(s):

Carbohydrate Binding ◽

Carbohydrate Binding Module ◽

Solution Structures

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The N-terminal family 22 carbohydrate-binding module of xylanase 10B ofClostridium themocellumis not a thermostabilizing domain

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.2004.tb09739.x ◽

2004 ◽

Vol 238 (1) ◽

pp. 71-78

Author(s):

Fernando M.V. Dias ◽

Arun Goyal ◽

Harry J. Gilbert ◽

JosÃ© A.M. Prates ◽

LuÃs M.A. Ferreira ◽

...

Keyword(s):

Carbohydrate Binding ◽

Carbohydrate Binding Module

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Genome Sequence of the Polysaccharide-Degrading, Thermophilic Anaerobe Spirochaeta thermophila DSM 6192

Journal of Bacteriology ◽

10.1128/jb.01023-10 ◽

2010 ◽

Vol 192 (24) ◽

pp. 6492-6493 ◽

Cited By ~ 13

Author(s):

Angel Angelov ◽

Susanne Liebl ◽

Meike Ballschmiter ◽

Mechthild Bömeke ◽

Rüdiger Lehmann ◽

...

Keyword(s):

Genome Sequence ◽

Complete Genome Sequence ◽

Glycoside Hydrolase ◽

Enzyme System ◽

Cellulose Degradation ◽

Carbohydrate Binding ◽

Carbohydrate Binding Module ◽

Free Living ◽

Genome Data ◽

Genes Encoding

ABSTRACT Spirochaeta thermophila is a thermophilic, free-living anaerobe that is able to degrade various α- and β-linked sugar polymers, including cellulose. We report here the complete genome sequence of S. thermophila DSM 6192, which is the first genome sequence of a thermophilic, free-living member of the Spirochaetes phylum. The genome data reveal a high density of genes encoding enzymes from more than 30 glycoside hydrolase families, a noncellulosomal enzyme system for (hemi)cellulose degradation, and indicate the presence of a novel carbohydrate-binding module.

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