title: Photoswitching of enzyme activity by laser-induced pH-jump.
abstract: Controlled initiation of biochemical events and in particular of protein activity is a powerful tool in biochemical research. Specifically, optical trigger signals are an attractive approach for remote control of enzyme activity. We present a method for generating optical control of enzyme activity applicable to a widespread range of enzymes. The approach is based on short laser pulses as optical "switches" introducing an instantaneous change of the pH-value for activation of protein function. The pH-jump is induced by proton release from 2-nitrobenzaldehyde. Reaction conditions were chosen to yield a pH-jump of almost 3 units on switching from inactive to active conditions for the enzyme. In this experimental setup, irradiation can be realized without any loss of enzyme activity. Following this change in pH-value, a controlled activation of hydrolytic activity of acid phosphatase is successfully demonstrated. This application provides a general method for photocontrol of enzymatic function for proteins having a significant pH-profile. The kinetic data for the substrate 6-chloro-8-fluoro-4-methylumbelliferone phosphate are determined.
authors.affiliation: Department of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, D-18059 Rostock, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Kohse
authors.forename: Antje
authors.initials: A
authors.lastname: Neubauer
authors.forename: Alexandra
authors.initials: A
authors.lastname: Pazidis
authors.forename: Stefan
authors.initials: S
authors.lastname: Lochbrunner
authors.forename: Udo
authors.initials: U
authors.lastname: Kragl
mesh_terms: D000135:Acid Phosphatase / Q000737:chemistry / Q000378:metabolism*; D001547:Benzaldehydes / Q000737:chemistry; D004789:Enzyme Activation; D006863:Hydrogen-Ion Concentration; D007834:Lasers; D015394:Molecular Structure; D055668:Photochemical Processes
chemical_list: D001547:Benzaldehydes; C043850:2-nitrobenzaldehyde; D000135:Acid Phosphatase