title: Submillisecond conformational changes in proteins resolved by photothermal beam deflection.
abstract: Photothermal beam deflection together with photo-acoustic calorimetry and thermal grating belongs to the family of photothermal methods that monitor the time-profile volume and enthalpy changes of light induced conformational changes in proteins on microsecond to millisecond time-scales that are not accessible using traditional stop-flow instruments. In addition, since overall changes in volume and/or enthalpy are probed, these techniques can be applied to proteins and other biomacromolecules that lack a fluorophore and or a chromophore label. To monitor dynamics and energetics of structural changes associated with Ca(2+) binding to calcium transducers, such neuronal calcium sensors, a caged calcium compound, DM-nitrophen, is employed to photo-trigger a fast (τ < 20 μsec) increase in free calcium concentration and the associated volume and enthalpy changes are probed using photothermal beam deflection technique.
authors.affiliation: Department of Chemistry and Biochemistry, Florida International University.
authors.forename: Walter G
authors.initials: WG
authors.lastname: Gonzalez
authors.affiliation: Department of Chemistry and Biochemistry, Florida International University; miksovsk@fiu.edu.
authors.forename: Jaroslava
authors.initials: J
authors.lastname: Miksovska
mesh_terms: D000085:Acetates / Q000737:chemistry; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D002151:Calorimetry / Q000379:methods*; D005029:Ethylenediamines / Q000737:chemistry; D007700:Kinetics; D051605:Kv Channel-Interacting Proteins / Q000737:chemistry* / Q000378:metabolism; D055668:Photochemical Processes; D011487:Protein Conformation; D013816:Thermodynamics; D013817:Thermography / Q000379:methods
chemical_list: D000085:Acetates; D005029:Ethylenediamines; D051605:Kv Channel-Interacting Proteins; C057014:DM-nitrophen; D002118:Calcium