title: Quenched molecular dynamics simulations of tuftsin and proposed cyclic analogues.
abstract: We have used high-temperature quenched molecular dynamics calculations to investigate the conformational properties of tuftsin (Thr-Lys-Pro-Arg) in solution. Conformers obtained after quenching of the dynamical structures were sorted into families depending on their relative energies and backbone conformations. By examination of these families, several cyclic analogues of tuftsin were proposed and examined theoretically by further quenched dynamics simulations. Two of the four proposed analogues were found to adopt essentially identical conformations to that of linear tuftsin. It is suggested that these two derivatives (cyclo[Thr-Lys-Pro-Arg-Gly] and cyclo[Thr-Lys-Pro-Arg-Asp]) may be biologically active, and that the introduction of cyclic conformational constraints should help to reduce the entropic penalty to peptide binding.
authors.affiliation: Department of Chemistry, University of Houston, Texas 77204-5641.
authors.forename: S D
authors.initials: SD
authors.lastname: O'Connor
authors.forename: P E
authors.initials: PE
authors.lastname: Smith
authors.forename: F
authors.initials: F
authors.lastname: al-Obeidi
authors.forename: B M
authors.initials: BM
authors.lastname: Pettitt
mesh_terms: D000595:Amino Acid Sequence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000737:chemistry*; D011487:Protein Conformation; D014405:Tuftsin / Q000031:analogs & derivatives / Q000737:chemistry*
chemical_list: D010456:Peptides, Cyclic; D014405:Tuftsin