Linked Life Data

11551191

Source:http://linkedlifedata.com/resource/pubmed/id/11551191

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
37
pubmed:dateCreated
2001-9-11
pubmed:abstractText
C-type lectin-like domains are very common components of extracellular proteins in animals. They bind to a variety of ligands, including carbohydrates, proteins, ice, and CaCO3 crystals. Their structure is characterized by long surface loops in the area of the protein usually involved in ligand binding. The C-type lectin TC14 from Polyandrocarpa misakiensis specifically binds to D-galactose by coordination of the sugar to a bound calcium atom. We have studied the dynamic properties of TC14 by measuring 15N longitudinal and transverse relaxation rates as well as [1H-15N] heteronuclear NOEs. Relaxation rates and heteronuclear NOE data for holo-TC14 show minimal variations, indicating that there is no substantial difference in rigidity between the elements of regular secondary structure and the extended surface loops. Anisotropic tumbling of the elongated TC14 dimer can account for the main fluctuations in relaxation rates. Loss of the bound calcium does not significantly alter the internal dynamics, suggesting that the stability of the loop region is intrinsic and not dependent on the coordination of the calcium ion. Chemical shift differences between the holo and apo form show that main structural changes occur in the calcium-binding site, but smaller structural changes are propagated throughout the molecule without affecting the overall fold. The disappearance of two resonances for residues following the conserved cis-proline 87 (which is located in the calcium-binding site) in the apo form indicates conformational change on an NMR time scale between the cis and trans configurations of this peptide bond in the absence of calcium. Possible implications of these findings for the ligand binding in C-type lectin-like domains are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10966-72
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
The ligand-binding loops in the tunicate C-type lectin TC14 are rigid.
pubmed:affiliation
MRC Centre for Protein Engineering, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't