Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1995-7-24
pubmed:abstractText
13CH2-multiplet nuclear magnetic resonance relaxation studies on proline (P)-containing glycine (G)-based peptides, GP, PG, GPG, PGG, and GPGG, provided numerous dipolar auto- and cross-correlation times for various motional model analyses of backbone and proline-ring bond rotations. Molecular dynamics simulations and bond rotation energy profiles were calculated to assess which motions could contribute most to observed relaxation phenomena. Results indicate that proline restricts backbone psi 1, psi 2, and phi 2 motions by 50% relative to those found for a polyglycine control peptide. psi 1 rotations are more restricted in the trans-proline isomer state than in the cis form. A two-state jump model best approximates proline ring puckering which in water could occur either by the C gamma endo-exo or by the C2 interconversion mechanism. The temperature dependence (5 degrees to 75 degrees C) of C beta, and C gamma, and C delta angular changes is rather flat, suggesting a near zero enthalpic contribution to the ring puckering process. In lower dielectric solvents, dimethylsulfoxide and methanol, which may mimic the hydrophobic environment within a protein, the endo-exo mechanism is preferred.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-3495
pubmed:author
pubmed:issnType
Print
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1540-50
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed-meshheading:7787039-Amino Acid Sequence, pubmed-meshheading:7787039-Anisotropy, pubmed-meshheading:7787039-Biophysical Phenomena, pubmed-meshheading:7787039-Biophysics, pubmed-meshheading:7787039-Carbon Isotopes, pubmed-meshheading:7787039-Computer Simulation, pubmed-meshheading:7787039-Dimethyl Sulfoxide, pubmed-meshheading:7787039-Glycine, pubmed-meshheading:7787039-Magnetic Resonance Spectroscopy, pubmed-meshheading:7787039-Methanol, pubmed-meshheading:7787039-Models, Chemical, pubmed-meshheading:7787039-Models, Molecular, pubmed-meshheading:7787039-Molecular Sequence Data, pubmed-meshheading:7787039-Molecular Structure, pubmed-meshheading:7787039-Motion, pubmed-meshheading:7787039-Oligopeptides, pubmed-meshheading:7787039-Proline, pubmed-meshheading:7787039-Rotation, pubmed-meshheading:7787039-Solvents, pubmed-meshheading:7787039-Stereoisomerism, pubmed-meshheading:7787039-Thermodynamics
pubmed:year
1995
pubmed:articleTitle
13C multiplet nuclear magnetic resonance relaxation-derived ring puckering and backbone dynamics in proline-containing glycine-based peptides.
pubmed:affiliation
Department of Biochemistry, University of Minnesota Health Sciences Center, Minneapolis 55455, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.