title: Formation of ion-selective channel using cyclic tetrapeptides.
abstract: It is important for ion channel peptides to have energetic stability and ion-selectivity for development of some medicines. In the present study, our objective was to achieve formation of energetically stable and ion-selective channels in the membrane using cyclic tetrapeptides. We succeeded in formation of energetically stable and ion-selective channels using two cyclic tetrapeptides cyclo(D-Ala-Dap)(2) (Dap; l-2,3-diaminopropionic acid) and cyclo(D-Ala-Glu)(2). The results of ion channel recording suggested that the cationic cyclo(D-Ala-Dap)(2) was resulted in Cl(-) anion-selective and the anionic cyclo(D-Ala-Glu)(2) led to K(+) cation-selective ion channel formation, respectively. This ion selectivity may be attributed to the charge state of peptides. And a low-hydrophobic cyclic tetrapeptide; cyclo(D-Ala-Dap)(2) had a tendency to form stable ion channel compared to more high-hydrophobic ones; cyclo(D-Phe-Lys)(2), cyclo(D-Phe-Dap)(2) and cyclo(D-Ala-Lys)(2). Our findings will shed light on the field of ion channel peptide study, especially cyclic one.
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, Saga University, 1 Honjo, Saga 840-8502, Japan.
authors.forename: Torao
authors.initials: T
authors.lastname: Suga
authors.forename: Satoshi
authors.initials: S
authors.lastname: Osada
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kodama
mesh_terms: D004151:Dipeptides / Q000138:chemical synthesis / Q000737:chemistry; D007473:Ion Channels / Q000138:chemical synthesis* / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000737:chemistry*; D017434:Protein Structure, Tertiary
chemical_list: D004151:Dipeptides; D007473:Ion Channels; D008051:Lipid Bilayers; D010456:Peptides, Cyclic; C038047:alanylaspartic acid; C045560:alanylglutamic acid