Mutant coat proteins of Pf3 bacteriophage as models of membrane proteins and their interactions with lipid bilayer membrane

Abstract

Pf3 coat protein, a protein coded by bacteriophage Pf3, is a short membrane spanning protein consisting from 44 amino acid residues. Its mutant protein 3L-Pf3, having three additional Leu residues in its transmembrane region, was demonstrated to be spontaneously inserted into large unilamellar vesicle (LUV), even in the absence of protein machineries or membrane potential. However, influences of the presence or absence of charged amino acids in the peptide on the manner of its insertion into LUV are still uncertain. In the present study, we designed new Pf3 mutants having His or Myc tags. These mutants were expressed in bacteria and added to the preformed LUV. Spontaneous insertion of these peptides into LUV was successfully observed.