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We highlight a convenient synthesis to selectively deuterate an aryl C–H hydrogen bond donor in an arylethynyl bisurea supramolecular anion receptor and use the Perrin method of competitive titrations to study the deuterium equilibrium isotope effects (DEIE) of anion binding for HS − , Cl − , and Br − . This work highlights the utility and also challenges in using this method to determine EIE with highly reactive and/or weakly binding anions.
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Allostery in oligomeric receptor models
Abstract We show how equilibrium binding curves of receptor homodimers can be expressed as rational polynomial functions of the equilibrium binding curves of the constituent monomers, without approximation and without assuming independence of receptor monomers. Using a distinguished spanning tree construction for reduced graph powers, the method properly accounts for thermodynamic constraints and allosteric interactions between receptor monomers (i.e. conformational coupling). The method is completely general; it begins with an arbitrary undirected graph representing the topology of a monomer state-transition diagram and ends with an algebraic expression for the equilibrium binding curve of a receptor oligomer composed of two or more identical and indistinguishable monomers. Several specific examples are analysed, including guanine nucleotide-binding protein-coupled receptor dimers and tetramers composed of multiple ‘ternary complex’ monomers.
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- Award ID(s):
- 1951646
- PAR ID:
- 10225383
- Date Published:
- Journal Name:
- Mathematical Medicine and Biology: A Journal of the IMA
- Volume:
- 37
- Issue:
- 3
- ISSN:
- 1477-8599
- Page Range / eLocation ID:
- 313 to 333
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/imammb/dqz016
