The macroscopic organization of reconstituted M13 coat protein-phospholipid systems. An EPR spectroscopy and polarizing microscope study.
The coat protein of the bacteriophage M13 in the alpha-helical state is reconstituted in macroscopically oriented systems of dioleoylphosphatidylcholine that are prepared by squeezing the reconstituted material between glass plates. The coat protein dramatically influences the macroscopic orientation of the multibilayers, as is investigated by polarizing microscopy and EPR spectroscopy of the cholestane spin label embedded in the bilayers. It is found that with increasing amounts of protein the spontaneous macroscopic orientation of the reconstituted system decreases. This effect is proposed to be due to an increase of the apparent viscosity of the lipid-protein systems with increasing amounts of protein. This is assumed to arise from a sticky effect of the C- and N-terminal protein parts that extend into the aqueous phase between the bilayers.
Department of Chemistry, University of Florence, Italy.
M F
MF
Ottaviani
H
H
Huinink
J C
JC
Sanders
M A
MA
Hemminga
D002213:Capsid / Q000737:chemistry*; D036022:Capsid Proteins; D004578:Electron Spin Resonance Spectroscopy; D008051:Lipid Bilayers / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D008859:Microscopy, Polarization; D015394:Molecular Structure; D010713:Phosphatidylcholines / Q000737:chemistry*; D013113:Spin Labels
D036022:Capsid Proteins; D008051:Lipid Bilayers; D008565:Membrane Proteins; D010713:Phosphatidylcholines; D013113:Spin Labels; C025668:coat protein, Bacteriophage M13; C017251:1,2-oleoylphosphatidylcholine