Expression, purification and enzymatic properties of a β-N-acetylhexosaminidase from brown planthopper, Nilaparvata lugens

A previous study demonstrated that a β- N -acetyl- d -hexosaminidase ( NlHex4 ) from the brown planthopper could serve as a new potential target for biopesticides due to its requirement for molting, and lethal phenotypes were observed via RNA interference . However, the enzymatic properties of NlHex4 remain unclear. In the present study, NlHex4 was expressed, purified and characterized. Recombinant NlHex4 was functionally expressed in baculovirus-infected insect cells and purified with a molecular weight of approximately 70   kDa. Recombinant NlHex4 had an optimal pH and temperature of 6.0 and 60   °C, respectively. Moreover, recombinant NlHex4 exhibited thermal stability at 50   °C for at least 1   h. Furthermore, the activity of recombinant NlHex4 was inhibited by the metal ions Fe 2   + and Fe 3   + and the serine protease inhibitor phenylmethanesulfonyl fluoride. These results reveal the enzymatic properties of NlHex4 and provide a basis for future investigation of the interaction between HEX and chitin oligosaccharide .