Akademik Veri Yönetim Sistemi
BIOPOLYMERS, cilt.33, sa.1, ss.173-192, 1993 (SCI-Expanded)
Low energy conformations have been generated for melittin, pancreatic polypeptide, and ribonuclease S-peptide, both in the vicinity of x-ray structures by energy refinement and by an unconstrained search over the entire conformational space. Since the structural polymorphism of these medium-sized peptides in crystal and solution is moderate, comparing the calculated conformations to x-ray and nmr data provides information on local and global behavior of potential functions. Local analysis includes standardization calculations, which show that models with standard geometry can approximate good resolution x-ray data with less than 0.5 angstrom rms deviation (RMSD). However, the atomic coordinates are shifted up to 2 angstrom RMSD by local energy minimization, and thus 2 angstrom is generally the smallest RMSD value one can target in a conformational search using the same energy evaluation models.