Work

Characterization of the structure and reactions of free radicals from serotonin and related indoles.

Year: 1981

Type: article

Abstract: The ESR spectra of the free radicals formed by the autoxidation of serotonin, 5-hydroxyindole, and 5-hydroxytryptophan in 1 N NaOH are presented. The analysis of the hyperfine splitting constants in H2O and D2O characterize these free radicals as semiquinone-imines, the one-electron oxidation product of the corresponding indole. At alkaline pH, autoxidation of these compounds ultimately leads to solid precipitate and unresolved ESR spectra characteristic of polymeric material. The reduction of cytochrome c at pH 7.4 by a wide variety of indoles correlates with the amplitude of the ESR signal in 1 N NaOH, as do other processes thought to be related to 5-hydroxyindole free radical formation. Relative to the rate of cytochrome c reduction, neither serotonin nor the serotonin free radical appears to react with oxygen to form superoxide. In the presence of NAD(P)H, the serotonin radical most probably oxidizes NAD(P)H to form the NAD(P). radical. The NAD(P). radical then reacts with oxygen to form superoxide, which ultimately reduces cytochrome c.

Source: Journal of Biological Chemistry

DOI: 10.1016/s0021-9258(19)69798-x

Authors: E. Perez-Reyes, R.P. Mason

Institutions: National Institutes of Health, National Institute of Environmental Health Sciences

Language: English

Topic: Electron Spin Resonance Studies

Subfield: Biophysics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Estimated APC paid: $3,430

OpenAlex ID: W1532273809