Tejo, Bimo A.Siahaan, Teruna J.2017-05-092017-05-092009-08Tejo, B. A., & Siahaan, T. J. (2009). Solution Structure of A Novel T-cell Adhesion Inhibitor Derived from the Fragment of ICAM-1 Receptor: Cyclo(1,8)-Cys-Pro-Arg-Gly-Gly-Ser-Val-Cys. Biopolymers, 91(8), 633–641. http://doi.org/10.1002/bip.21192https://hdl.handle.net/1808/24047This is the peer reviewed version of the following article: Tejo, B. A., & Siahaan, T. J. (2009). Solution Structure of A Novel T-cell Adhesion Inhibitor Derived from the Fragment of ICAM-1 Receptor: Cyclo(1,8)-Cys-Pro-Arg-Gly-Gly-Ser-Val-Cys. Biopolymers, 91(8), 633–641. http://doi.org/10.1002/bip.21192, which has been published in final form at doi.org/10.1002/bip.21192. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingThis study is aimed at elucidating the structure of a novel T-cell adhesion inhibitor, cyclo(1,8)-CPRGGSVC using one- and two-dimensional 1H NMR and molecular dynamics (MD) simulation. The peptide is derived from the sequence of its parent peptide cIBR (cyclo(1,12)-PenPRGGSVLVTGC), which is a fragment of intercellular adhesion molecule-1 (ICAM-1). Our previous results show that the cyclo(1,8)-CPRGGSVC peptide binds to the LFA-1 I-domain and inhibits heterotypic T-cell adhesion, presumably by blocking the LFA-1/ICAM-1 interactions. The structure of the peptide was determined using NMR and MD simulation in aqueous solution. Our results indicate that the peptide adopts type-I β-turn conformation at the Pro2-Arg3-Gly4-Gly5 (PRGG) sequence. The β-turn structure at the PRGG motif is well conserved in cIBR peptide and ICAM-1 receptor, which suggests the importance of the PRGG motif for the biological activity of cyclo(1,8)-CPRGGSVC peptide. Meanwhile, the Gly5-Ser6-Val7-Cys8-Cys1 (GSVCC) sequence forms a “turn-like” random coil structure that does not belong to any structured motif. Therefore, cyclo(1,8)-CPRGGSVC peptide has only one structured region at the PRGG sequence, which may play an important role in the binding of the peptide to the LFA-1 I-domain. The conserved β-turn conformation of the PRGG motif in ICAM-1, cIBR, and cyclo(1,8)-CPRGGSVC peptides can potentially be used to design peptidomimetics.© 2009 Wiley Periodicals, Inc.Autoimmune diseasesβ-turnICAM-1LFA-1T-cell adhesionArticle10.1002/bip.21192PMC2742958openAccess