Facile reaction of gangliosides with hydroxyl radical

N Konagaya; M Inagaki; S Nishikawa; N Kashimura

doi:10.1080/13510002.1996.11747047

Facile reaction of gangliosides with hydroxyl radical

Redox Rep. 1996 Jun;2(3):185-9. doi: 10.1080/13510002.1996.11747047.

Authors

N Konagaya¹, M Inagaki¹, S Nishikawa¹, N Kashimura¹

Affiliation

¹ a Laboratory of Biofunctional Chemistry, Department of Bioscience, Faculty of Bioresources , Mie University , Tsu , Japan .

PMID: 27406075
DOI: 10.1080/13510002.1996.11747047

Abstract

The reactivity of gangliosides with superoxide anion (O2(•-)) and hydroxyl radical (HO(•)) was evaluated by ESR spin-trapping using 5,5-dimethyl-1-pyrroline-N-oxide under physiological conditions (1/15 M phosphate buffer, pH 7.4). Gangliosides proved to react with HO(•) but not with O2(•-). The second order rate constants for various gangliosides with HO(•) ranged from 5 × 10(9) M(-1)s(-1) to 16 × 10(9) M(-1)s(-1). The rate constant for tetrasialoganglioside, GQ1b, was about three times higher than that of monosialoganglioside, GM1. The reactivity of gangliosides and asialo-GM1 with HO(•) was in the order: GQ1b >GT1b >GD1a >GD1b = GM1 ≫ asialo-GM1. The observed high reactivity of gangliosides probably involves the sialyl residues, since sialic acid was shown to be more reactive with HO(•) than d-glucose under the same conditions.