Modulation of yeast hexokinase on bio-inspired membranes

Hexokinase (HK) is the first enzyme of the glycolytic pathway and is known to modulate its own activity by binding to the mitochondrial membrane. In this study, the enzymatic activity of HK was measured in the presence of various liposomes. The positively charged liposome with an appropriate charge density was found to increase the HK activity. The HK activity was enhanced 1.5-fold in the presence of 5 mol% didodecyldimethylammonium bromide (DDAB) and 1.8-fold with 5–10 mol% 3β-[N-(N′,N′-dimethylaminoethane)-carbamoyl] cholesterol hydrochloride (DC-Cholesterol) on the POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocoline) liposome. Analysis of (i) HK binding onto liposome, (ii) intrinsic Trp fluorescence, and (iii) circular dichroism of HK suggested that the HK activity was enhanced on positively charged microdomain because of its slight conformational change through the electrostatic and hydrophobic interactions.

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► The positively charged liposome enhanced the enzymatic activity of hexokinase (HK).
► HK activity was enhanced 1.8-fold on liposome with positively-charged microdomain.
► HK activity was enhanced because of its slight conformational change on the liposome.