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</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1cwb ConSurf]. | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1cwb ConSurf]. | ||
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== Publication Abstract from PubMed == | |||
For most of the cyclosporin A (CsA) analogs, there is generally a good correlation between cyclophilin binding and immunosuppression. However, this relationship does not seem to hold for 4-[(E)-2-butenyl]-4,4,N-trimethyl-L-threonine1 (MeBm2t)1-CsA. Its affinity for cyclophilin was reported to be approximately 1% that of CsA and its immunosuppressive activity in vitro was shown to be approximately 30% that of CsA. We report here the crystal structure of a complex between recombinant human cyclophilin A (CypA) and (MeBm2t)1-CsA which has been determined by X-ray crystallography at 2.2 A resolution and refined to an R-factor of 16.3%. (MeBm2t)1-CsA shows a similar bound conformation and network of interactions to CypA as CsA. The measured lower affinity for CypA cannot therefore be explained by a different mode of binding. We propose that the poor affinity to CypA could be accounted for by the existence of an equilibrium in aqueous solution between a 'cyclophilin bound conformation' and a 'non-binding conformation' of (MeBm2t)1-CsA. The relatively high immunosuppressive activity is suggested to result from slight conformational differences observed in the effector domain. | |||
The X-ray structure of (MeBm2t)1-cyclosporin complexed with cyclophilin A provides an explanation for its anomalously high immunosuppressive activity.,Mikol V, Kallen J, Walkinshaw MD Protein Eng. 1994 May;7(5):597-603. PMID:8073029<ref>PMID:8073029</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
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<div class="pdbe-citations 1cwb" style="background-color:#fffaf0;"></div> | |||
==See Also== | ==See Also== | ||
*[[Cyclophilin 3D structures|Cyclophilin 3D structures]] | *[[Cyclophilin 3D structures|Cyclophilin 3D structures]] | ||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> |
Latest revision as of 08:26, 5 June 2024
THE X-RAY STRUCTURE OF (MEBM2T)1-CYCLOSPORIN COMPLEXED WITH CYCLOPHILIN A PROVIDES AN EXPLANATION FOR ITS ANOMALOUSLY HIGH IMMUNOSUPPRESSIVE ACTIVITYTHE X-RAY STRUCTURE OF (MEBM2T)1-CYCLOSPORIN COMPLEXED WITH CYCLOPHILIN A PROVIDES AN EXPLANATION FOR ITS ANOMALOUSLY HIGH IMMUNOSUPPRESSIVE ACTIVITY
Structural highlights
FunctionPPIA_HUMAN PPIases accelerate the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedFor most of the cyclosporin A (CsA) analogs, there is generally a good correlation between cyclophilin binding and immunosuppression. However, this relationship does not seem to hold for 4-[(E)-2-butenyl]-4,4,N-trimethyl-L-threonine1 (MeBm2t)1-CsA. Its affinity for cyclophilin was reported to be approximately 1% that of CsA and its immunosuppressive activity in vitro was shown to be approximately 30% that of CsA. We report here the crystal structure of a complex between recombinant human cyclophilin A (CypA) and (MeBm2t)1-CsA which has been determined by X-ray crystallography at 2.2 A resolution and refined to an R-factor of 16.3%. (MeBm2t)1-CsA shows a similar bound conformation and network of interactions to CypA as CsA. The measured lower affinity for CypA cannot therefore be explained by a different mode of binding. We propose that the poor affinity to CypA could be accounted for by the existence of an equilibrium in aqueous solution between a 'cyclophilin bound conformation' and a 'non-binding conformation' of (MeBm2t)1-CsA. The relatively high immunosuppressive activity is suggested to result from slight conformational differences observed in the effector domain. The X-ray structure of (MeBm2t)1-cyclosporin complexed with cyclophilin A provides an explanation for its anomalously high immunosuppressive activity.,Mikol V, Kallen J, Walkinshaw MD Protein Eng. 1994 May;7(5):597-603. PMID:8073029[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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