Influence of the intramolecular disulfide Cys46-Cys55 bridge on the interaction of human neuroglobin with SDS
Year: 2025
Type: article
Abstract: Human neuroglobin (hNgb) is a globin involved in the protection of neurons and retinal cells which features an intramolecular disulfide bond between Cys46 and Cys55 under oxidative conditions. Here, conformational changes and oxidative degradation of hNgb wt and its C46AC55A mutant, lacking the disulfide bridge, were investigated in the presence of sodium dodecyl sulfate (SDS) by electronic absorption spectroscopy, intrinsic fluorescence emission and circular dichroism. Both proteins are found to undergo multiple SDS-induced conformational changes resulting in the formation of two non-native high spin species (HS1 and HS2). Moreover, increasing SDS concentration enhances the rate of heme breakdown by H 2 O 2 . Deletion of the Cys46-Cys55 disulfide bridge amplifies the conformational effect of SDS and appreciably increases heme oxidative degradation by H 2 O 2 . The effect of SDS on the structure and oxidative degradation of wt human neuroglobin and its C46AC55A mutant was investigated. Increasing SDS concentrations induce multiple conformational changes and enhance the rate of H 2 O 2 -induced heme breakdown. Deletion of the disulfide bridge increases the conformational effect of SDS and heme oxidative degradation. • SDS effect on structure and oxidative degradation of human neuroglobin is investigated. • Multiple SDS-induced conformational changes are observed. • Increasing SDS concentrations enhance the rate of heme breakdown by H 2 O 2 . • Removal of the Cys46-Cys55 disulfide bond enhances the conformational effect of SDS. • Removal of the Cys46-Cys55 disulfide bond boosts heme oxidative degradation by H 2 O 2 .
Institution: University of Modena and Reggio Emilia
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,220
Awards: G1412229944, G731809726
OpenAlex ID: W4415075912