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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
9
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pubmed:dateCreated |
1988-10-4
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pubmed:abstractText |
Cyclosporine A (CsA, 1), an immunosuppressive cyclic undecapeptide, in apolar solvents adopts a II' beta-turn at the Sar3-MeLeu4 residues. [D-Proline3]Cs has been reported to be a nonimmunosuppressive analogue in which the II' beta-turn is retained. In order to determine if this loss of activity is caused by steric hindrance between the Cs analogue and its receptor or is caused by a change in the peptide conformation, an analogue that stabilizes a II' beta-turn has been synthesized, [lactam3,4]Cs. We also have studied the solution conformation of two other analogues, [D-MeAla3]Cs and [L-MeAla3]Cs. The conformations have been established by 1D difference NOE and 2D (NOESY or ROESY) NMR. The conformations of [lactam3,4]Cs and [D-MeAla3]Cs are indistinguishable from that of CsA in solution. [L-MeAla3]Cs was found to adopt a conformation with a cis amide bond between Sar3 and MeLeu4. The inhibition of concanavalin A stimulated thymocytes by CsA, [D-MeAla3]Cs, [L-MeAla3]Cs, and [lactam3,4]Cs gave IC50 values (nM) of 5, 6, 100, and 100, respectively. The weak immunosuppressive activity of [lactam3,4]Cs possessing the II' beta-turn suggests that the loss of activity for 4 is due to steric hindrance with the Cs receptor.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Sep
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pubmed:issn |
0022-2623
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
31
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1805-15
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:3261799-Animals,
pubmed-meshheading:3261799-Chemical Phenomena,
pubmed-meshheading:3261799-Chemistry,
pubmed-meshheading:3261799-Concanavalin A,
pubmed-meshheading:3261799-Cyclosporins,
pubmed-meshheading:3261799-Hydrogen Bonding,
pubmed-meshheading:3261799-Immunosuppression,
pubmed-meshheading:3261799-Magnetic Resonance Spectroscopy,
pubmed-meshheading:3261799-Mice,
pubmed-meshheading:3261799-Molecular Conformation,
pubmed-meshheading:3261799-Solvents,
pubmed-meshheading:3261799-Structure-Activity Relationship,
pubmed-meshheading:3261799-T-Lymphocytes,
pubmed-meshheading:3261799-Temperature
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pubmed:year |
1988
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pubmed:articleTitle |
Synthesis, conformation, and immunosuppressive activity of a conformationally restricted cyclosporine lactam analogue.
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pubmed:affiliation |
University of Wisconsin, School of Pharmacy, Madison 53706.
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pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.,
Research Support, Non-U.S. Gov't
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