Protein-protein interaction in purple membrane.
We present experimental evidence for a long-range protein-protein interaction in purple membrane (PM). The interprotein dynamics were quantified by measuring the spectrum of the acoustic phonons in the 2D bacteriorhodopsin (BR) protein lattice using inelastic neutron scattering. Phonon energies of about 1 meV were determined. The data are compared to an analytical model, and the effective spring constant for the interaction between neighboring protein trimers are determined to be k = 53 N/m. Additional, optical-like excitations at 0.45 meV were found and assigned to intraprotein dynamics between neighboring BR monomers.
Rheinstädter
Maikel C
MC
Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1, Canada. rheinstadter@mcmaster.ca
Schmalzl
Karin
K
Wood
Kathleen
K
Strauch
Dieter
D
D001436:Bacteriorhodopsins / Q000737:chemistry* / Q000378:metabolism*; D033363:Neutron Diffraction; D025941:Protein Interaction Mapping; D018717:Purple Membrane / Q000737:chemistry* / Q000378:metabolism*; D013816:Thermodynamics
D001436:Bacteriorhodopsins