Single-molecule electrophoresis of beta-hairpin peptides by electrical recordings and Langevin dynamics simulations.
We used single-channel electrical recordings and Langevin molecular dynamics simulations to explore the electrophoretic translocation of various beta-hairpin peptides across the staphylococcal alpha-hemolysin (alphaHL) protein pore at single-molecule resolution. The beta-hairpin peptides, which varied in their folding properties, corresponded to the C terminal residues of the B1 domain of protein G. The translocation time was strongly dependent on the electric force and was correlated with the folding features of the beta-hairpin peptides. Highly unfolded peptides entered the pore in an extended conformation, resulting in fast single-file translocation events. In contrast, the translocation of the folded beta-hairpin peptides occurred more slowly. In this case, the beta-hairpin peptides traversed the alphaHL pore in a misfolded or fully folded conformation. This study demonstrates that the interaction between a polypeptide and a beta-barrel protein pore is dependent on the folding features of the polypeptide.
Goodrich
Carl P
CP
Kirmizialtin
Serdal
S
Huyghues-Despointes
Beatrice M
BM
Zhu
Aiping
A
Scholtz
J Martin
JM
Makarov
Dmitrii E
DE
Movileanu
Liviu
L
D000107:Acetylation; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001426:Bacterial Proteins / Q000737:chemistry*; D001427:Bacterial Toxins / Q000737:chemistry*; D003198:Computer Simulation; D004586:Electrophoresis / Q000379:methods; D006460:Hemolysin Proteins / Q000737:chemistry*; D008051:Lipid Bilayers; D008564:Membrane Potentials; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D021381:Protein Transport
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; C034284:IgG Fc-binding protein, Streptococcus; D008051:Lipid Bilayers; D010455:Peptides; C021091:staphylococcal alpha-toxin