Characterization of digestive α- and β-glucosidases in the midgut of Plagiodera versicolora Laicharting (Coleoptera: Chrysomelidae)
نویسندگان
1 Department of Plant Protection, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran.
2 Department of Plant Protection, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran
doi
چکیده
The imported willow leaf beetle, Plagiodera versicolora is one of the main pests of forest trees worldwide including Iran. Activities of α- and β-glucosidases in the midgut of P. versicolora adults were studied in this research. The results showed a higher α- glucosidase activity of adultsthan β-glucosidase. The optimal pHs for α- and β-glucosidases activities were found to be 6 and 9, respectively. Optimal temperatures for the enzymatic activities were recorded at 30 and 25 °C, respectively. Concentration of 0.5 mM K+ significantly minimized the activity of α- glucosidase and maximized the activity of α-glucosidase in presence of Ca2+. The activity of β-glucosidase was decreased by adding Mg2+ and Zn2+. 5 mM concentration of K+ had the most inhibitory impact on β-glucosidase activity, while 0.5 mM concentration of Na+ showed the most positive effect on the enzyme activity. The Km of midgut α- and β- glucosidase was 0.36 and 2.03 mM and the Vmax value was 5.46 and 18.51 μmol/min/mg protein, respectively.
