854670-32-9Relevant academic research and scientific papers
A Redox-Based Superoxide Generation System Using Quinone/Quinone Reductase
Singh, Shailesh Kumar,Husain, Syed Masood
, p. 1657 - 1663 (2018/08/17)
Superoxide (O2.?) generation in biological systems is achieved through some of the most complex enzymatic systems. Of these, only xanthine/xanthine oxidase has been used for in vitro biochemical studies. However, it suffers from limitations such as a lack of suitable heterologous expression system for xanthine oxidase and the irreversible consumption and low solubility of xanthine under physiological conditions. Herein, we report a redox-based, enzyme-catalyzed system, in which autoxidation of hydroquinone to quinone via semiquinone results in superoxide generation. Quinone is reduced back to hydroquinone by using the NfsB (oxygen-insensitive nitroreductase) enzyme of Escherichia coli strain K-12 and nicotinamide adenine dinucleotide phosphate hydride (NADPH; which is regenerated by using the glucose/glucose dehydrogenase system). This new system relies on quinones that can be recycled and have superior water solubility, as well as enzymes that are heterologously expressed. By using a variety of quinones and reaction conditions, along with a comparison of real-time fluorescence, menadione has been identified as the optimal substrate for superoxide generation. The new redox-based system presents a viable alternative for studying the biochemistry of superoxide under different physiological and pathological conditions.
Hydropropidine: A novel, cell-impermeant fluorogenic probe for detecting extracellular superoxide
Michalski, Radoslaw,Zielonka, Jacek,Hardy, Micael,Joseph, Joy,Kalyanaraman, Balaraman
, p. 135 - 147 (2013/02/25)
Here we report the synthesis and characterization of a membrane-impermeant fluorogenic probe, hydropropidine (HPr+), the reduction product of propidium iodide, for detecting extracellular superoxide (O2 ?-). HPr+/sup
Hydroethidine as a probe for measuring superoxide formation rates during air oxidation of myricetin and quercetin
Quek, Yi Ling,Huang, Dejian
scheme or table, p. 5384 - 5387 (2011/10/30)
In the presence of the flavonols myricetin and quercetin, oxidation of hydroethidine (HE) by superoxide yielded ethidium (E+) instead of 2-hydroxyethidium (2-OH-E+). As a known pro-oxidant, myricetin alone was also found to be able to catalyze air oxidation of HE yielding exclusively E+. The reaction is inhibited by added superoxide dismutase, suggesting that superoxide is involved in the rate limiting step of the oxidation.
Quenching and generation of singlet oxygen by hydroethidine and related chromophores
Bilski,Karriker,Chignell
scheme or table, p. 116 - 119 (2009/12/26)
We have found that the oxidative probe hydroethidine (HE) is an efficient 1O2 quencher with kq = 1.1 × 109 M-1 s-1 in CH3CN. The structurally related MitoSOX Red had kq/sub
