title: Oxime Catalysis by Freezing.
abstract: Chemical reaction rates are generally decreased at lower temperatures. Here, we report that an oxime ligation reaction in water at neutral pH is accelerated by freezing. The freezing method and its rate effect on oxime ligation are systematically studied on a peptide model system, and applied to a larger chemokine protein, containing a single acetyl butyrate group, which is conjugated to an aminooxy-labeled ligand. Our improved ligation protocol now makes it possible to efficiently introduce oxime-bond coupled ligands into proteins under aqueous conditions at low concentrations and neutral pH.
authors.affiliation: Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), University Maastricht , Maastricht 6229 ER, The Netherlands.
authors.forename: Stijn M
authors.initials: SM
authors.lastname: Agten
authors.affiliation: Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), University Maastricht , Maastricht 6229 ER, The Netherlands.
authors.forename: Dennis P L
authors.initials: DP
authors.lastname: Suylen
authors.affiliation: Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), University Maastricht , Maastricht 6229 ER, The Netherlands.
authors.forename: Tilman M
authors.initials: TM
authors.lastname: Hackeng
mesh_terms: D002087:Butyrates / Q000737:chemistry; D002384:Catalysis; D018946:Chemokine CCL5 / Q000737:chemistry*; D005615:Freezing; D006863:Hydrogen-Ion Concentration; D007659:Ketones / Q000737:chemistry; D008024:Ligands; D008239:Lysine / Q000737:chemistry; D010091:Oximes / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D002087:Butyrates; D018946:Chemokine CCL5; D007659:Ketones; D008024:Ligands; D010091:Oximes; D010455:Peptides; D014867:Water; D008239:Lysine