ANSTO Publications Online >
Journal Publications >
Journal Articles >

Please use this identifier to cite or link to this item: http://apo.ansto.gov.au/dspace/handle/10238/2402

Title: Changes in small-angle x-ray scattering parameters observed upon binding of ligand to rabbit muscle pyruvate kinase are not correlated with allosteric transitions.
Authors: Fenton, AW
Williams, R
Trewhella, J
Keywords: Rabbits
Muscles
Small Angle Scattering
Ligands
Phosphoenolpyruvate
Amino Acids
Issue Date: 24-Aug-2010
Publisher: American Chemical Society
Citation: Fenton, A. W., Williams, R., & Trewhella, J. (2010). Changes in small-angle x-ray scattering parameters observed upon binding of ligand to rabbit muscle pyruvate kinase are not correlated with allosteric transitions. Biochemistry, 49(33), 7202-7209.
Abstract: Protein fluorescence and small-angle X-ray scattering (SAXS) have been used to monitor effector affinity and conformational changes previously associated with allosteric regulation in rabbit muscle pyruvate kinase (M-1-PYK). In the absence of substrate [phosphoenolpyruvate (PEP)], SAXS-monitored conformational changes in M-1-PYK elicited by the binding of phenylalanine (an allosteric inhibitor that reduces the affinity of M-1-PYK for PEP) are similar to those observed upon binding of alanine or 2-aminobutyric acid. Under our assay conditions, these small amino acids bind to the protein but elicit a minimal change in the affinity of the protein for PEP. Therefore, if changes in scattering signatures represent cleft closure via domain rotation as previously interpreted, we can conclude that these motions are not sufficient to elicit allosteric inhibition. Additionally, although PEP has similar affinities for the free enzyme and the M-1-PYK small amino acid complexes (i.e., the small amino acids have minimal allosteric effects), PEP binding elicits different changes in the SAXS signature of the free enzyme versus the M-1-PYK small amino acid complexes. © 2010, American Chemical Society
URI: http://dx.doi.org/10.1021/bi100147w
http://apo.ansto.gov.au/dspace/handle/10238/2402
ISSN: 0006-2960
Appears in Collections:Journal Articles

Files in This Item:

There are no files associated with this item.

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

 

Valid XHTML 1.0! DSpace Software Copyright © 2002-2010  Duraspace - Feedback