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Porphyrin ?-stacking in a heme protein scaffold tunes gas ligand affinity.

ABSTRACT: The role of ?-stacking in controlling redox and ligand binding properties of porphyrins has been of interest for many years. The recent discovery of H-NOX domains has provided a model system to investigate the role of porphyrin ?-stacking within a heme protein scaffold. Removal of a phenylalanine-porphyrin ?-stack dramatically increased O2, NO, and CO affinities and caused changes in redox potential (~40mV) without any structural changes. These results suggest that small changes in redox potential affect ligand affinity and that ?-stacking may provide a novel route to engineer heme protein properties for new functions.

SUBMITTER: Weinert EE

PROVIDER: S-EPMC3773300 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Porphyrin π-stacking in a heme protein scaffold tunes gas ligand affinity.

Weinert Emily E EE Phillips-Piro Christine M CM Marletta Michael A MA

Journal of inorganic biochemistry 20130615

The role of π-stacking in controlling redox and ligand binding properties of porphyrins has been of interest for many years. The recent discovery of H-NOX domains has provided a model system to investigate the role of porphyrin π-stacking within a heme protein scaffold. Removal of a phenylalanine-porphyrin π-stack dramatically increased O2, NO, and CO affinities and caused changes in redox potential (~40mV) without any structural changes. These results suggest that small changes in redox potenti ...[more]

PMID: 23831583

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