75286-43-0Relevant academic research and scientific papers
Solubilizing Protective Groups for Enzymatic Peptide Syntheses. Studies with Polyoxyethylene-Supported Substrates
Koennecke, Andreas,Pchalek, Volker,Jakubke, Hans-Dieter
, p. 111 - 118 (2007/10/02)
The utility of amino acids and dipeptides esterified to solubilizing polyoxyethylene supports as substrates for protease-mediated peptide bond formation was studied using free and immobilized α-chymotrypsin as a catalyst.Poor yields were obtained with Nα-protected amino acid or dipeptide polyoxyethylene esters as carboxyl components, most probably due to a shielding of the active site of the acyl enzyme intermediate by the polymer favouring hydrolytic cleavage.Experiments with polyoxyethylene esters as nucleophiles gave good results with free chymotrypsin, immobilized chymotrypsin predominantly caused hydrolysis of the ester carboxyl component due to unfavourable interactions between the soluble and insoluble polymers.Keywords: Chymotrypsin; Enzymatic peptide synthesis; Liquid phase peptide synthesis; Solubilizing protective groups; Polyoxyethylene
Studies on the Influence of Reaction Conditions on the α-Chymotrypsin-catalyzed Peptide Synthesis in an Aqueous-Organic Two-phase System
Kuhl, P.,Walpuski, J.,Jakubke, H.-D.
, p. 766 - 768 (2007/10/02)
α-Chymotrypsin treated with water-immiscible organic solvents exhibits a much less diminished specific hydrolytic activity towards Glt-Leu-Phe-Nan than in the presence of DMF or methanol.The dependence of product yield on the organic solvent, enzyme concentration, reaction time, and the addition of salts has been studied at the synthesis of Ac-Leu-Phe-Leu-NH2 from Ac-Leu-Phe-OMe and Leu-NH2.Furthermore, the effect of the concentration of nucleophile and enzyme as well as the reaction time on the synthesis of the corresponding Z-protected tripeptide amide has been determined.
Peptide Synthesis by Means of Immobilized Enzymes. I. Immobilized α-Chimotripsin
Koennecke, Andreas,Bullerjahn, Ralf,Jakubke, Hans-Dieter
, p. 469 - 482 (2007/10/02)
α-Chymotrypsin covalently bound to silica, enzacryl AA, and enzacryl AH catalyzes peptide bond formation between N-protected dipeptide methyl esters and H-Leu-NH2 with results similar to those with the free enzyme.The influence of water-miscible and water
Model Studies on Papain-Catalyzed Peptide Synthesis in a Biphasic Aqueous-Organic System
Doering, Guenter,Kuhl, Peter,Jakubke, Hans-Dieter
, p. 1165 - 1174 (2007/10/02)
Several model peptides have been synthesized enzymatically using papain as a catalyst in biphasic aqueous-organic systems.The effect of different cosolvents, pH, buffer concentration, and reaction time on the papain-catalyzed synthesis was examined.A comp
α-Chymotrypsin-catalyzed Synthesis of Tripeptide Amides in an Aqueous-Organic Two-phase System
Kuhl, P.,Posselt, Siegrid,Jakubke, H.-D.
, p. 463 - 465 (2007/10/02)
α-Chymotrypsin catalyzes in a biphasic system containing an organic solvent and hydrogencarbonate buffer the reaction of Boc-Leu-Phe-OMe with X-NH2 (X=Leu, Met, Val) forming Boc-tripeptide amides.In the case of X=Leu the addition of ammoniumsulfate is advantageous and allows the use of carboxyl and amino component in equivalent amounts.By the same method Z-protected tripeptide amides can be prepared from Z-X-Phe-OMe (X=Ala, Leu, Val) and Leu-NH2 in good yields.In some case α-chymotrypsin-catalyzed peptide coupling is also possible, if the buffer solution is substituted for crystal water containing sodium carbonate.
