title: Picosecond absorption studies on the photodissociation of alpha- and beta-nitrosyl hemoglobin monomers.
abstract: Transient absorption studies of the pump-probe type were performed on the NO forms of the alpha- and beta-monomers of hemoglobin using a Nd3+ phosphate-glass laser. A second harmonic 531-nm, 8-ps fwhm pulse pumped the Q-band while a delayed continuum generated pulse was used to monitor pi pi* Soret absorption changes in the 410-453-nm region. Photodissociation of nitrosyl alpha- and beta-monomers was found to differ markedly from the tetramer in what we believe to be the formation of a five-coordinate HbNO (with proximal imidazole detached) photoproduct within the first 50 ps after photon absorption.
authors.affiliation: Department of Chemistry, University of Wyoming, Laramie 82071.
authors.forename: C R
authors.initials: CR
authors.lastname: Guest
authors.forename: L J
authors.initials: LJ
authors.lastname: Noe
mesh_terms: D006454:Hemoglobins / Q000378:metabolism* / Q000528:radiation effects; D007700:Kinetics; D007834:Lasers; D046911:Macromolecular Substances; D008962:Models, Theoretical; D010782:Photolysis; D013053:Spectrophotometry; D013997:Time Factors
chemical_list: D006454:Hemoglobins; D046911:Macromolecular Substances; C008657:nitrosyl hemoglobin