title: Modeling the electrophoresis of highly charged peptides: application to oligolysines.
abstract: The "coarse-grained" bead modeling methodology, BMM, is generalized to treat electrostatics at the level of the nonlinear Poisson-Boltzmann equation. This improvement makes it more applicable to the important class of highly charged macroions and highly charged peptides in particular. In the present study, the new nonlinear Poisson-Boltzmann, NLPB-BMM procedure is applied to the free solution electrophoretic mobility of low molecular mass oligolysines (degree of polymerization 1-8) in lithium phosphate buffer at pH 2.5. The ionic strength is varied from 0.01 to 0.10 M) and the temperature is varied from 25 to 50°C. In order to obtain quantitative agreement between modeling and experiment, a small amount of specific phosphate binding must be included in modeling. This binding is predicted to increase with increasing temperature and ionic strength.
authors.affiliation: Department of Chemistry, Georgia State University, Atlanta, GA 30302-4098, USA.
authors.forename: Hengfu
authors.initials: H
authors.lastname: Wu
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Allison
authors.forename: Catherine
authors.initials: C
authors.lastname: Perrin
authors.forename: Herve
authors.initials: H
authors.lastname: Cottet
mesh_terms: D024202:Electrophoretic Mobility Shift Assay; D008958:Models, Molecular; D009994:Osmolar Concentration; D010455:Peptides / Q000302:isolation & purification*; D011107:Polylysine / Q000302:isolation & purification*; D013696:Temperature
chemical_list: D010455:Peptides; D011107:Polylysine