Document Detail

Carbohydrate affinity for the glucose-galactose binding protein is regulated by allosteric domain motions.
MedLine Citation:
PMID:  23148479     Owner:  NLM     Status:  Publisher    
Protein function, structure and dynamics are intricately correlated, but studies on structure-activity relationships are still only rarely complemented by a detailed analysis of dynamics related to function (functional dynamics). Here, we have applied NMR to investigate the functional dynamics in two homologous periplasmic sugar binding proteins with bi-domain composition: E.coli glucose/galactose (GGBP) and ribose (RBP) binding proteins. In contrast to their structural and functional similarity, we observe a remarkable difference in functional dynamics: For RBP, the absence of segmental motions allows only for isolated structural adaptations upon carbohydrate binding in line with an induced fit mechanism; on the other hand, GGBP shows extensive segmental mobility in both apo and holo states, enabling selection of the most favorable conformation upon carbohydrate binding in line with a population shift mechanism. Collective segmental motions are controlled by the hinge composition: by swapping two identified key residues between RBP and GGBP we also interchange their segmental hinge mobility, and the doubly mutated GGBP* no longer experiences changes in conformational entropy upon ligand binding while the complementary RBP* shows the segmental dynamics observed in wtGGBP. Most importantly, the segmental inter-domain dynamics always increase the apparent substrate affinity and thus, are functional, underscoring the allosteric control that the hinge region exerts on ligand binding.
Gabriel Ortega; David Castaño; Tammo Diercks; Oscar Millet
Related Documents :
3096929 - Studies on pristinamycin synergism in staphylococcus aureus.
8869639 - Site-directed mutagenesis of arg58 and asp86 of elongation factor tu from escherichia c...
2207159 - Potential binding sites of the trans-activator fis are present upstream of all rrna ope...
11160889 - Ribosomal protein s7 from escherichia coli uses the same determinants to bind 16s ribos...
3057439 - The elongation factor ef-tu from e. coli binds to the upstream activator region of the ...
3888269 - On the structural specificity of puromycin binding to escherichia coli ribosomes.
15199149 - Ctbp contributes quantitatively to knirps repression activity in an nad binding-depende...
19679509 - Study on the interaction between methyl violet and bovine serum albumin by spectral ana...
23006599 - Rab11-family of interacting protein 2 associates with chlamydial inclusions through its...
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2012-11-14
Journal Detail:
Title:  Journal of the American Chemical Society     Volume:  -     ISSN:  1520-5126     ISO Abbreviation:  J. Am. Chem. Soc.     Publication Date:  2012 Nov 
Date Detail:
Created Date:  2012-11-14     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  7503056     Medline TA:  J Am Chem Soc     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Multiexciton Annihilation and Dissociation in Quantum Confined Semiconductor Nanocrystals.
Next Document:  Prevalence and Clinical Profile of Resistant Hypertension among Treated Hypertensive Subjects.