Papain-Catalyzed Peptide Bond Formation: Enzyme-Specific Activation with Guanidinophenyl Esters
作者:Roseri J. A. C. de Beer、Barbara Zarzycka、Helene I. V. Amatdjais-Groenen、Sander C. B. Jans、Timo Nuijens、Peter J. L. M. Quaedflieg、Floris L. van Delft、Sander B. Nabuurs、Floris P. J. T. Rutjes
DOI:10.1002/cbic.201100267
日期:2011.9.19
Fooling with substrate recognition: Guanidinophenyl (OGp) esters were utilized as potential substrate mimetics for papain‐induced dipeptide synthesis under aqueous conditions. Surprisingly, modeling studies instead revealed unprecedented enzyme‐specific activation, applicable to nearly all amino acids.
Papain-Specific Activating Esters in Aqueous Dipeptide Synthesis
作者:Roseri J. A. C. de Beer、Barbara Zarzycka、Michiel Mariman、Helene I. V. Amatdjais-Groenen、Marc J. Mulders、Peter J. L. M. Quaedflieg、Floris L. van Delft、Sander B. Nabuurs、Floris P. J. T. Rutjes
DOI:10.1002/cbic.201200017
日期:2012.6.18
A set of new activating esters was evaluated in an enzymatic, papain‐catalyzed approach to synthesizing dipeptides under aqueous conditions. In particular, benzyl and dimethylaminophenyl esters yielded the corresponding dipeptides in several instances in high yields and with relatively small levels of hydrolysis. These results were also interpreted by computational docking analysis.
Synthesis and binding affinities of analogs of cholecystokinin-(30-33) as probes for central nervous system cholecystokinin receptors
作者:David C. Horwell、Andrew Beeby、Colin R. Clark、John Hughes
DOI:10.1021/jm00387a027
日期:1987.4
CCK-30-33 has been identified as the minimum fragment of CCK with nanomolar affinity for the central CCK receptors, as assayed by displacement of [3H]-Boc-beta-alanyl-CCK-30-33 (pentagastrin) in homogenized mouse cerebral cortex. Examination of binding using this assay in the two series Boc-Trp-X-Phe-NH2 when X = Met-Asp (Boc-CCK-30-33), Gly-Asp, Met-Gly, and Gly-Gly and when X = (CH2)n (n = 0-4) reveals that modification of the tetrapeptide reduces affinity to a maximum of micromolar affinity (Boc-Trp-Gly-Asp-Phe-NH2; Ki = 2 X 10(-6) M), whereas in the series when n = 0 and 2 pentamolar affinity is still retained (Boc-Trp-Phe-NH2, Ki = 7 X 10(-5) M; Boc-Trp NH CH2-CH2-CO-Phe-NH2, Ki = 3 X 10(-5) M). Modification of the tetrapeptide CCK-30-33 reduces affinity 1000-fold, whereas di- and tripeptide fragments are identified that reduce affinity only a further 10-fold. This structure-activity relationship establishes a basis to design "peptoid" analogues of CCK that have therapeutic potential.