title: Optical measurements of long-range protein vibrations.
abstract: Protein biological function depends on structural flexibility and change. From cellular communication through membrane ion channels to oxygen uptake and delivery by haemoglobin, structural changes are critical. It has been suggested that vibrations that extend through the protein play a crucial role in controlling these structural changes. While nature may utilize such long-range vibrations for optimization of biological processes, bench-top characterization of these extended structural motions for engineered biochemistry has been elusive. Here we show the first optical observation of long-range protein vibrational modes. This is achieved by orientation-sensitive terahertz near-field microscopy measurements of chicken egg white lysozyme single crystals. Underdamped modes are found to exist for frequencies >10 cm(-1). The existence of these persisting motions indicates that damping and intermode coupling are weaker than previously assumed. The methodology developed permits protein engineering based on dynamical network optimization.
authors.affiliation: Department of Physics, University at Buffalo, SUNY, 239 Fronczak Hall, Buffalo, New York 14260, USA.
authors.forename: Gheorghe
authors.initials: G
authors.lastname: Acbas
authors.affiliation: Department of Physics, University at Buffalo, SUNY, 239 Fronczak Hall, Buffalo, New York 14260, USA.
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Niessen
authors.affiliation: Department of Structural Biology, Hauptman-Woodward Medical Research Institute, University at Buffalo, SUNY, 700 Ellicott St., Buffalo, New York 14203, USA.
authors.forename: Edward H
authors.initials: EH
authors.lastname: Snell
authors.affiliation: 1] Department of Physics, University at Buffalo, SUNY, 239 Fronczak Hall, Buffalo, New York 14260, USA [2] Department of Structural Biology, Hauptman-Woodward Medical Research Institute, University at Buffalo, SUNY, 700 Ellicott St., Buffalo, New York 14203, USA.
authors.forename: A G
authors.initials: AG
authors.lastname: Markelz
mesh_terms: D000818:Animals; D002645:Chickens; D003460:Crystallization; D008853:Microscopy / Q000379:methods; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009113:Muramidase / Q000737:chemistry*; D055096:Optical Devices; D055068:Terahertz Spectroscopy / Q000379:methods*; D014732:Vibration
chemical_list: C421864:hen egg lysozyme; D009113:Muramidase