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Applicability of fluorescence-based sensors to the determination of kinetic parameters for O? in oxygenases.

ABSTRACT: Optical methods for O2 determination based on dynamic fluorescence quenching have been applied to measure oxygen uptake rates in cell culture and to determine intracellular oxygen levels. Here we demonstrate the applicability of fluorescence-based probes in determining kinetic parameters for O2 using as an example catalysis by a cofactor-independent oxygenase (DpgC). Fluorescence-based sensors provide a direct assessment of enzyme-catalyzed O2 consumption using commercially available, low-cost instrumentation that is easily customizable and, thus, constitutes a convenient alternative to the widely used Clark-type electrode, especially in cases where chemical interference is expected to be problematic.

SUBMITTER: Di Russo NV

PROVIDER: S-EPMC4402703 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Applicability of fluorescence-based sensors to the determination of kinetic parameters for O₂ in oxygenases.

Di Russo Natali V NV Bruner Steven D SD Roitberg Adrian E AE

Analytical biochemistry 20150128

Optical methods for O2 determination based on dynamic fluorescence quenching have been applied to measure oxygen uptake rates in cell culture and to determine intracellular oxygen levels. Here we demonstrate the applicability of fluorescence-based probes in determining kinetic parameters for O2 using as an example catalysis by a cofactor-independent oxygenase (DpgC). Fluorescence-based sensors provide a direct assessment of enzyme-catalyzed O2 consumption using commercially available, low-cost i ...[more]

PMID: 25637681

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