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Accurate proton affinity and gas-phase basicity values for molecules important in biocatalysis.

ABSTRACT: Benchmark quantum calculations of proton affinities and gas-phase basicities of molecules relevant to biochemical processes, particularly acid/base catalysis, are presented and compared for a variety of multilevel and density functional quantum models. Included are nucleic acid bases in both keto and enol tautomeric forms, ribose in B-form and A-form sugar pucker conformations, amino acid side chains and backbone molecules, and various phosphates and phosphoranes, including thio substitutions. This work presents a high-level thermodynamic characterization of biologically relevant protonation states and provides a benchmark database for development of next-generation semiempirical and approximate density functional quantum models and parametrization of methods to predict pK(a) values and relative solvation energies.

SUBMITTER: Moser A

PROVIDER: S-EPMC2970571 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Accurate proton affinity and gas-phase basicity values for molecules important in biocatalysis.

Moser Adam A Range Kevin K York Darrin M DM

The journal of physical chemistry. B 20101101 43

Benchmark quantum calculations of proton affinities and gas-phase basicities of molecules relevant to biochemical processes, particularly acid/base catalysis, are presented and compared for a variety of multilevel and density functional quantum models. Included are nucleic acid bases in both keto and enol tautomeric forms, ribose in B-form and A-form sugar pucker conformations, amino acid side chains and backbone molecules, and various phosphates and phosphoranes, including thio substitutions. T ...[more]

PMID: 20942500

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