Effect of surfactants on peroxidase activity. III. Effect of nonionic surfactants

Inhibition of horseradish peroxidase activity through conformational change in surfactant solution

“…However, for dilute SB3‐12 solutions, the α ‐helix content strongly increased with surfactant concentration, reaching a maximum value at 1.5 mM (slightly below the cmc, 2.71 ± 0.05 mM), and then underwent a slight decrease upon a further increase of SB3‐12 concentration. It is noteworthy that the surfactant concentration where the α ‐helix content was highest corresponds to the concentration where the highest activity of HRP was observed (Figure 2), suggesting that the increase in the α ‐helix content reflected an increase of enzymatic activation for SB3‐12, which is in contrast to SDS and DTAB (Davletshin et al, 1998). For SB3‐12 concentrations above the cmc, the α ‐helix content remains at a high level (Figure 3), even though the activity of HRP was greatly diminished (Figure 2).…”

“…The effect of surfactants on the HRP activity has been widely reported, and the properties of the surfactants also play an important role. For instance, the anionic surfactant SDS at an aqueous concentration far below its critical micelle concentration (cmc) can inhibit the activity of HRP (Nazari et al, 2005), while the activity of the HRP first increases and then decreases with increasing concentration for some cationic surfactants (Davletshin et al, 1998) and nonionic surfactants (Davletshin & Egorov, 2000). The activity change of HRP exhibited in these buffered surfactant solutions is mainly induced by the interaction between the surfactants and HRP (Moosavi‐Movahedi, 2005; Moosavi‐Movahedi et al, 1997).…”

Enzymatic reduction of halogenated aryl ketones in an aqueous micellar solution with enhanced catalytic performance

“…The reason might be due to that on the one hand, the excess surfactant stripped away the essential water molecules from its surface and catalytically active sites, leading to inhibition and conformational change, and on the other hand, the excess surfactant induced the formation of more micellar particles, extracting more substrates into the micelles and inhibiting contact with the external enzyme. [30][31][32] Hence, a suitable surfactant concentration is required to strike a balance between solubilization and over-extraction. Furthermore, as shown in Fig.…”