title: Protease-catalyzed peptide synthesis in frozen aqueous systems: the "freeze-concentration model".
abstract: Freezing of the aqueous reaction mixtures can cause dramatically increased peptide yields in protease-catalyzed kinetically controlled peptide synthesis reactions. The "Freeze-concentration model" which implies that the enzymic reaction within a macroscopically frozen system takes place in an unfrozen liquid phase is presented as a reasonable basis for the understanding of the effect of freezing. It is shown that L-amino acid esters are effective nucleophiles in alpha-chymotrypsin-catalyzed acyl transfer reactions when these are performed in frozen state.
authors.affiliation: Department of Biochemistry, Leipzig University, FRG.
authors.forename: M
authors.initials: M
authors.lastname: Schuster
authors.forename: A
authors.initials: A
authors.lastname: Aaviksaar
authors.forename: M
authors.initials: M
authors.lastname: Haga
authors.forename: U
authors.initials: U
authors.lastname: Ullmann
authors.forename: H D
authors.initials: HD
authors.lastname: Jakubke
mesh_terms: D000595:Amino Acid Sequence; D002918:Chymotrypsin / Q000737:chemistry; D004151:Dipeptides / Q000138:chemical synthesis / Q000737:chemistry; D010450:Endopeptidases / Q000737:chemistry*; D005615:Freezing; D007700:Kinetics; D008956:Models, Chemical; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D014867:Water
chemical_list: D004151:Dipeptides; D010455:Peptides; D014867:Water; D010450:Endopeptidases; D002918:Chymotrypsin