title: Temperature-Jump Fluorescence Provides Evidence for Fully Reversible Microsecond Dynamics in a Thermophilic Alcohol Dehydrogenase.
abstract: Protein dynamics on the microsecond (μs) time scale were investigated by temperature-jump fluorescence spectroscopy as a function of temperature in two variants of a thermophilic alcohol dehydrogenase: W87F and W87F:H43A. Both mutants exhibit a fast, temperature-independent μs decrease in fluorescence followed by a slower full recovery of the initial fluorescence. The results, which rule out an ionizing histidine as the origin of the fluorescence quenching, are discussed in the context of a Trp49-containing dimer interface that acts as a conduit for thermally activated structural change within the protein interior.
authors.forename: Corey W
authors.initials: CW
authors.lastname: Meadows
authors.affiliation: ∥Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
authors.forename: Gurusamy
authors.initials: G
authors.lastname: Balakrishnan
authors.affiliation: ∥Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
authors.forename: Brandon L
authors.initials: BL
authors.lastname: Kier
authors.affiliation: ∥Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Spiro
authors.forename: Judith P
authors.initials: JP
authors.lastname: Klinman
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005453:Fluorescence; D001411:Geobacillus stearothermophilus / Q000201:enzymology; D006639:Histidine / Q000737:chemistry; D009154:Mutation; D011487:Protein Conformation; D055503:Protein Multimerization; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013696:Temperature; D014364:Tryptophan / Q000737:chemistry
chemical_list: D006639:Histidine; D014364:Tryptophan; D000426:Alcohol Dehydrogenase