title: Long-lived amide I vibrational modes in myoglobin.
abstract: Pump-probe experiments in the infrared measure vibrational relaxation rates. Myoglobin, which is almost entirely alpha helix in secondary structure, has an unusually long, nonexponential excited state relaxation generated by optically pumping at the blue side ( 5. 85 microm) of the amide I band. The amino acid alanine and the predominantly beta sheet protein photoactive yellow protein do not have such a long-lived state, suggesting that the alpha helix in proteins can support nonlinear states of 15 ps characteristic times.
authors.affiliation: Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74708, USA.
authors.forename: A
authors.initials: A
authors.lastname: Xie
authors.forename: L
authors.initials: L
authors.lastname: van Der Meer
authors.forename: W
authors.initials: W
authors.lastname: Hoff
authors.forename: R H
authors.initials: RH
authors.lastname: Austin
mesh_terms: D000577:Amides / Q000737:chemistry*; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry; D007700:Kinetics; D007834:Lasers; D008958:Models, Molecular; D009211:Myoglobin / Q000737:chemistry*; D020283:Photoreceptors, Microbial; D017433:Protein Structure, Secondary; D013055:Spectrophotometry, Infrared; D014732:Vibration; D014907:Whales
chemical_list: D000577:Amides; D001426:Bacterial Proteins; D009211:Myoglobin; D020283:Photoreceptors, Microbial; C050162:photoactive yellow protein, Bacteria