Please use this identifier to cite or link to this item: https://ir.swu.ac.th/jspui/handle/123456789/14841
ชื่อเรื่อง: Chiral protein scissors activated by light: Recognition and protein photocleavage by a new pyrenyl probe
ผู้แต่ง: Buranaprapuk A.
Malaikaew Y.
Svasti J.
Kumar C.V.
Keywords: Absorption
Amines
Binding energy
Body fluids
Chirality
Enantiomers
Pneumatic control equipment
Proteins
Volumetric analysis
Amino groups
Binding affinities
Binding constants
Bovine-serum albumin
Chiral discrimination
D-phenylalanine
L-phenylalanine
Model proteins
Photo cleavage
Site-selective
Amino acids
วันที่เผยแพร่: 2008
บทคัดย่อ: Strong chiral discrimination and site-selective photocleavage of two model proteins, lysozyme and bovine serum albumin (BSA), by new pyrenyl probes are reported here. The enantiomeric pyrenyl probes D-phenylalanine-1(1-pyrene) methylamide (PMA-D-Phe) and L-phenylalanine-1(1-pyrene)methylamide (PMA-L-Phe) were synthesized by coupling the carboxyl function of D-phenylalanine or L-phenylalanine with the amino group of 1(1-pyrene)methylamine. Binding affinities of the two enantiomers with the proteins were quantitated in absorption titrations. BSA indicated 10-fold selectivity for PMA-D-Phe, and the binding constants for the L- and D-enantiomers were 3.8 × 105 and 4.0 × 106 M-1, respectively. Lysozyme, similarly, indicated a 6-fold preference for PMA-D-Phe with binding constants of 3.3 × 105 and 2.0 × 106 M-1 for the L- and D-isomers, respectively. Such strong chiral discrimination illustrates the key role of the chiral center of the probe (Phe) in the binding interactions. The enantiomers were tested to examine how the chiral discrimination for their binding influences reactivity toward protein photocleavage. Irradiation of the probe-protein complexes, at 342 nm in the presence of hexammine cobalt(ill) chloride, resulted in the cleavage of the protein backbone. Photocleavage did not proceed in the dark or in the absence of the pyrenyl probes. Both enantiomers indicated low reactivity with BSA (<5% yield), while large photocleavage yields (∼57%) have been noted with lysozyme. This lysozyme photocleavage yield is a significant improvement over previous reports. However, both enantiomers cleaved lysozyme at the same location between Trp108-Val109, despite the strong chiral selectivity for binding. H-atom abstraction from Trp 108, accessible from the active site cleft, could initiate the observed peptide bond cleavage. © 2008 American Chemical Society.
URI: https://ir.swu.ac.th/jspui/handle/123456789/14841
https://www.scopus.com/inward/record.uri?eid=2-s2.0-49349107295&doi=10.1021%2fjp802791c&partnerID=40&md5=f75048928a7b966c554dcea9c90c4151
ISSN: 15206106
Appears in Collections:Scopus 1983-2021

Files in This Item:
There are no files associated with this item.


Items in SWU repository are protected by copyright, with all rights reserved, unless otherwise indicated.