Comparison of two reducing agents dithiothreitol and tris(3-hydroxypropyl)phosphine for in vitro kinetic assay of vitamin K epoxide reductase

Kazuki Takeda; Ayuko Morita; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka

Veterinary and Animal Science (Jun 2020)

Comparison of two reducing agents dithiothreitol and tris(3-hydroxypropyl)phosphine for in vitro kinetic assay of vitamin K epoxide reductase

Kazuki Takeda,
Ayuko Morita,
Yoshinori Ikenaka,
Shouta M.M. Nakayama,
Mayumi Ishizuka

Affiliations

Kazuki Takeda: Department of Environmental Sciences, Laboratory of Toxicology, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan
Ayuko Morita: Department of Environmental Sciences, Laboratory of Toxicology, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan
Yoshinori Ikenaka: Department of Environmental Sciences, Laboratory of Toxicology, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
Shouta M.M. Nakayama: Department of Environmental Sciences, Laboratory of Toxicology, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan
Mayumi Ishizuka: Department of Environmental Sciences, Laboratory of Toxicology, Graduate School of Veterinary Medicine, Hokkaido University, Kita-18 Nishi-9, Kita-ku, Sapporo 060-0818, Japan; Corresponding author.

Journal volume & issue: Vol. 9
p. 100095

Abstract

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Vitamin K epoxide reductase (VKOR) is a target enzyme for anticoagulants, such as warfarin, that are used as medicines or rodenticides. Assessing VKOR activity is required to ensure the proper usage of these drugs. Dithiothreitol (DTT) is a typical disulfide reductant that is used as a substrate for in vitro VKOR assays. However, DTT is considered problematic because of its side effects. Tris(3-hydroxypropyl)phosphine (THP) has been found to be a reliable alternative to DTT, as shown by kinetic analyses of the VKOR with them. THP showed significantly lower Vmax and Km values than those of DTT; however, there was no significant difference in their Vmax/Km and IC50 for warfarin.

Published in Veterinary and Animal Science

ISSN: 2451-943X (Online)
Publisher: Elsevier
Country of publisher: Netherlands
LCC subjects: Agriculture: Animal culture: Veterinary medicine
Website: https://www.journals.elsevier.com/veterinary-and-animal-science/

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