title: Evidence for two geminate rebinding states following laser photolysis of R state hemoglobin encapsulated in wet silica gels.
abstract: In this letter we report the first experimental evidence for CO rebinding to human hemoglobin from multiple geminate states. The analysis of the rebinding kinetics using a maximum entropy method allowed the identification of two distinct rebinding states within the protein matrix, which become populated under conditions of increased viscosity in a silica gel at high glycerol concentration. Our findings suggest the presence of at least two distinct docking sites for the photolyzed ligand. Assuming a minimal four-state model, we estimate the microscopic rates and the activation energies for the elementary processes.
authors.forename: Silvia
authors.initials: S
authors.lastname: Sottini
authors.forename: Stefania
authors.initials: S
authors.lastname: Abbruzzetti
authors.forename: Cristiano
authors.initials: C
authors.lastname: Viappiani
authors.forename: Stefano
authors.initials: S
authors.lastname: Bettati
authors.forename: Luca
authors.initials: L
authors.lastname: Ronda
authors.forename: Andrea
authors.initials: A
authors.lastname: Mozzarelli
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry*; D005782:Gels / Q000737:chemistry; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D010782:Photolysis; D012822:Silicon Dioxide / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D005782:Gels; D006454:Hemoglobins; D012822:Silicon Dioxide; D002248:Carbon Monoxide