Solvent isotope and viscosity effects on the steady-state kinetics of the flavoprotein nitroalkane oxidase

Giovanni Gadda; Paul F. Fitzpatrick

doi:10.1016/j.febslet.2013.04.021

Solvent isotope and viscosity effects on the steady-state kinetics of the flavoprotein nitroalkane oxidase

Giovanni Gadda, Paul F. Fitzpatrick

Department of Biochemistry & Structural Biology

Research output: Contribution to journal › Article › peer-review

13 Scopus citations

Abstract

The flavoprotein nitroalkane oxidase catalyzes the oxidative denitrification of a broad range of primary and secondary nitroalkanes to yield the respective aldehydes or ketones, hydrogen peroxide and nitrite. With nitroethane as substrate the ^D2O(k_cat/K_M) value is 0.6 and the ^D2Ok_cat value is 2.4. The k_cat proton inventory is consistent with a single exchangeable proton in flight, while the k_cat/K_M is consistent with either a single proton in flight in the transition state or a medium effect. Increasing the solvent viscosity did not affect the k_cat or k_cat/K _M value significantly, establishing that nitroethane binding is at equilibrium and that product release does not limit k_cat.

Original language	English (US)
Pages (from-to)	2785-2789
Number of pages	5
Journal	FEBS Letters
Volume	587
Issue number	17
DOIs	https://doi.org/10.1016/j.febslet.2013.04.021
State	Published - Sep 2 2013

Keywords

Flavoprotein
Michaelis-Menten kinetics
Nitroalkane oxidase
Solvent isotope effect
Viscosity

ASJC Scopus subject areas

Biophysics
Structural Biology
Biochemistry
Molecular Biology
Genetics
Cell Biology

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10.1016/j.febslet.2013.04.021

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title = "Solvent isotope and viscosity effects on the steady-state kinetics of the flavoprotein nitroalkane oxidase",

abstract = "The flavoprotein nitroalkane oxidase catalyzes the oxidative denitrification of a broad range of primary and secondary nitroalkanes to yield the respective aldehydes or ketones, hydrogen peroxide and nitrite. With nitroethane as substrate the D2O(kcat/KM) value is 0.6 and the D2Okcat value is 2.4. The kcat proton inventory is consistent with a single exchangeable proton in flight, while the kcat/KM is consistent with either a single proton in flight in the transition state or a medium effect. Increasing the solvent viscosity did not affect the kcat or kcat/K M value significantly, establishing that nitroethane binding is at equilibrium and that product release does not limit kcat.",

keywords = "Flavoprotein, Michaelis-Menten kinetics, Nitroalkane oxidase, Solvent isotope effect, Viscosity",

author = "Giovanni Gadda and Fitzpatrick, {Paul F.}",

note = "Funding Information: This work was supported in part by NIH Grant GM 58698 . The assistance of Damon Choe in carrying out assays is gratefully acknowledged.",

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doi = "10.1016/j.febslet.2013.04.021",

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T1 - Solvent isotope and viscosity effects on the steady-state kinetics of the flavoprotein nitroalkane oxidase

AU - Gadda, Giovanni

AU - Fitzpatrick, Paul F.

N1 - Funding Information: This work was supported in part by NIH Grant GM 58698 . The assistance of Damon Choe in carrying out assays is gratefully acknowledged.

PY - 2013/9/2

Y1 - 2013/9/2

N2 - The flavoprotein nitroalkane oxidase catalyzes the oxidative denitrification of a broad range of primary and secondary nitroalkanes to yield the respective aldehydes or ketones, hydrogen peroxide and nitrite. With nitroethane as substrate the D2O(kcat/KM) value is 0.6 and the D2Okcat value is 2.4. The kcat proton inventory is consistent with a single exchangeable proton in flight, while the kcat/KM is consistent with either a single proton in flight in the transition state or a medium effect. Increasing the solvent viscosity did not affect the kcat or kcat/K M value significantly, establishing that nitroethane binding is at equilibrium and that product release does not limit kcat.

AB - The flavoprotein nitroalkane oxidase catalyzes the oxidative denitrification of a broad range of primary and secondary nitroalkanes to yield the respective aldehydes or ketones, hydrogen peroxide and nitrite. With nitroethane as substrate the D2O(kcat/KM) value is 0.6 and the D2Okcat value is 2.4. The kcat proton inventory is consistent with a single exchangeable proton in flight, while the kcat/KM is consistent with either a single proton in flight in the transition state or a medium effect. Increasing the solvent viscosity did not affect the kcat or kcat/K M value significantly, establishing that nitroethane binding is at equilibrium and that product release does not limit kcat.

KW - Flavoprotein

KW - Michaelis-Menten kinetics

KW - Nitroalkane oxidase

KW - Solvent isotope effect

KW - Viscosity

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DO - 10.1016/j.febslet.2013.04.021

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AN - SCOPUS:84883050815

SN - 0014-5793

VL - 587

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JO - FEBS Letters

JF - FEBS Letters

IS - 17

ER -

Solvent isotope and viscosity effects on the steady-state kinetics of the flavoprotein nitroalkane oxidase

Abstract

Keywords

ASJC Scopus subject areas

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