Metal Clips Induce Folding of a Short Unstructured Peptide into an a-Helix via Turn Conformations in Water. Kinetic versus Thermodynamic Products


Autoria(s): Beyer, Renee L.; Hoang, Huy N.; Appleton, Trevor G.; Fairlie, David P.
Contribuinte(s)

Peter Stang

Data(s)

01/01/2004

Resumo

Short peptides corresponding to two to four a-helical turns of proteins are not thermodynamically stable helices in water. Unstructured octapeptide Ac-His1*-Ala2-Ala3-His4*-His5*-Glu6-Leu7-His8*-NH2 (1) reacts with two [Pd ((NH2)-N-15(CH2)(2) (NH2)-N-15)(NO3)(2)] in water to form a kinetically stable intermediate, [{Pden}(2)-{(1,4)(5,8)-peptide}](2), in which two 19-membered metallocyclic rings stabilize two peptide turns. Slow subsequent folding to a thermodynamically more stable two-turn a-helix drives the equilibrium to [{Pden}(2)-{(1,5)(4,8)-peptide}] (3), featuring two 22-membered rings. This transformation from unstructured peptide via turns to an a-helix suggests that metal clips might be useful probes for investigating peptide folding.

Identificador

http://espace.library.uq.edu.au/view/UQ:73594

Idioma(s)

eng

Publicador

American Chemical Society

Palavras-Chave #Chemistry, Multidisciplinary #Nuclear-magnetic-resonance #Protein Secondary Structure #Ion Enhanced Helicity #Amino-acids #Coupling-constants #Copper(ii) Complexes #Stability-constants #Circular-dichroism #Crystal-structure #Nmr-spectroscopy #C1 #250301 Organic Chemical Synthesis #780103 Chemical sciences
Tipo

Journal Article