Linked Life Data

2051485

Source:http://linkedlifedata.com/resource/pubmed/id/2051485

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1991-7-19
pubmed:abstractText
The structure of the small squash trypsin inhibitor CMTI-I is refined by directly minimizing the difference between the observed two-dimensional nuclear Overhauser enhancement (NOE) intensities and those calculated by the full relaxation matrix approach. To achieve this, a term proportional to this difference was added to the potential energy function of the molecular dynamics program X-PLOR. Derivatives with respect to atomic co-ordinates are calculated analytically. Spin diffusion effects are thus accounted for fully during the refinement. Initial structures for the refinement were those determined recently by solution nuclear magnetic resonance using the isolated two-spin approximation to derive distance range estimates. The fits to the nuclear magnetic resonance data improve significantly with only small shifts in the refined structures during a few cycles of conjugate gradient minimization. However, larger changes (approximately 1 A) in the conformation occur during simulated annealing, which is accompanied by a further reduction of the difference between experimental and calculated two-dimensional NOE intensities. The refined structures are closer to the X-ray structure of the inhibitor complexed with trypsin than the initial structures. The root-mean-square difference for backbone atoms between the initial structures and the X-ray structure is 0.96 A, and that between the refined structures and the X-ray structure 0.61 A.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
219
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
499-510
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Relaxation matrix refinement of the solution structure of squash trypsin inhibitor.
pubmed:affiliation
Howard Hughes Medical Institute, Yale University, New Haven, CT 06511.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't