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Effector analogues detect varied allosteric roles for conserved protein-effector interactions in pyruvate kinase isozymes.

ABSTRACT: The binding site for allosteric inhibitor (amino acid) is highly conserved between human liver pyruvate kinase (hL-PYK) and the rabbit muscle isozyme (rM(1)-PYK). To detail similarities/differences in the allosteric function of these two homologues, we quantified the binding of 45 amino acid analogues to hL-PYK and their allosteric impact on affinity for the substrate, phosphoenolpyruvate (PEP). This complements a similar study previously completed for rM(1)-PYK. In hL-PYK, the minimum chemical requirements for effector binding are the same as those identified for rM(1)-PYK (i.e., the l-2-aminopropanaldehyde substructure of the effector is primarily responsible for binding). However, different regions of the effector determine the magnitude of the allosteric response in hL-PYK vs rM(1)-PYK. This finding is inconsistent with the idea that allosteric pathways are conserved between homologues of a protein family.

SUBMITTER: Alontaga AY

PROVIDER: S-EPMC3062439 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Effector analogues detect varied allosteric roles for conserved protein-effector interactions in pyruvate kinase isozymes.

Alontaga Aileen Y AY Fenton Aron W AW

Biochemistry 20110214 11

The binding site for allosteric inhibitor (amino acid) is highly conserved between human liver pyruvate kinase (hL-PYK) and the rabbit muscle isozyme (rM(1)-PYK). To detail similarities/differences in the allosteric function of these two homologues, we quantified the binding of 45 amino acid analogues to hL-PYK and their allosteric impact on affinity for the substrate, phosphoenolpyruvate (PEP). This complements a similar study previously completed for rM(1)-PYK. In hL-PYK, the minimum chemical ...[more]

PMID: 21261284

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