Studies on the relationship between structure and electrophoretic mobilityof alpha-helical and beta-sheet peptides using capillary zone electrophoresis

The electrophoretic behaviour of a series of 33 different synthetic peptide s has been investigated using free solution high-performance capillary zona l electrophoretic (HPCZE) methods. The dependency of the electrophoretic mo bility, mu(em), on the peptide charge, q, and on the charge-to-size ratio p arameter, zeta, determined according to several electromobility models, hav e been examined. Significant divergences from linearity in the mu(em) vs. q or the mu(em) vs. zeta plots were noted for several peptides, possibly due to the proclivity of specific arrangements of their amino acid sequences t o assume preferred alpha-helical or beta-sheet conformational features rath er than random coil structures under the HPCZE conditions. These results pr ovide further demonstration of the facility of HPCZE procedures to probe th e effects of compositional, sequential and conformational differences of cl osely-related peptides and their consequences on their physicochemical beha viour in solution. (C) 1999 Elsevier Science B.V. All rights reserved.