3n25
From Proteopedia
The structure of muscle pyruvate kinase in complex with proline, pyruvate, and Mn2+
Structural highlights
FunctionKPYM_RABIT Glycolytic enzyme that catalyzes the transfer of a phosphoryl group from phosphoenolpyruvate (PEP) to ADP, generating ATP. Stimulates POU5F1-mediated transcriptional activation (By similarity). Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedIn the study of rabbit muscle pyruvate kinase (M(1)-PYK), proline has previously been used as an osmolyte in an attempt to determine a role for pre-existing conformational equilibria in allosteric regulation. In this context, osmolytes are small molecules assumed to have no direct interaction with the protein. In contrast to its proposed role as an osmolyte, the structure of M(1)PYK-Mn-pyruvate-proline complex reported herein demonstrates that proline binds specifically to the allosteric site of M(1)-PYK. Therefore, this amino acid is an allosteric effector, rather than a benign osmolyte. Other compounds often used as osmolytes (polyethyleneglycol and glycerol) are also present in the structure, suggesting an interaction with the protein that would, in turn, prevent the usefulness of these compounds in the study of this and most likely other proteins. These findings highlight the need to verify that compounds used as osmolytes to perturb pre-existing conformational equilibrium do not directly interact with the protein, a consideration not commonly addressed in the past. The pyruvate kinase model system, a cautionary tale for the use of osmolyte perturbations to support conformational equilibria in allostery.,Fenton AW, Johnson TA, Holyoak T Protein Sci. 2010 Jul 13. PMID:20629175[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|