Biochemical characterization of galactosidase enzymes in the Melon ladybird, Epilachna chrysomelina Foure (Col.: Coccinellidae)

Ghanbarinezhad, Rouhangiz; Ghadamyari, Mohammad; Hasan Sajedi, Reza; Gholamzadeh-Chitgar, Molood

doi:10.22055/ppr.2015.11373

Biochemical characterization of galactosidase enzymes in the Melon ladybird, Epilachna chrysomelina Foure (Col.: Coccinellidae)

Document Type : Research paper-Persian

Authors

Rouhangiz Ghanbarinezhad

Mohammad Ghadamyari

Reza Hasan Sajedi

Molood Gholamzadeh-Chitgar

10.22055/ppr.2015.11373

Abstract

Melon ladybird, Epilachna chrysomelina (F.) is one of major pests of cucurbitaceous plants. Larvae and adults feed on host plants and cause serious damage to them. Study of the digestive enzymes is necessary for engineering resistant host plants to pests. By determination of the biochemical characteristics of the digestive carbohydrases, the necessary information can be supplied for application of resistant plants containing inhibitors. In the present study, biochemical properties of galactosidases were studied in the alimentary canal of melon ladybird. The measuring of the enzymes activity in the digestive system of the 2^nd, 3^rd and 4^thinstars, female and male adults showed that the highest specific activity of digestive enzymes was in the digestive system of the 3^rd instar and the enzyme activities in the male and female digestive systems did not show any significant difference. The optimal pH and temperature for galactosidases activity in the alimentary canal were found to be 5 and 40°C, respectively. The K_m values of α and β galactosidases in the gut of E. chrysomelina were 0.013 and 0.02 mM, respectively. The results of zymogram pattern in the native gel revealed that α- and β-galactosidases had one isoform in the alimentary canal of E. chrysomelina.

Keywords

Melon ladybird

α- and β-galactosidase

Biochemical characterization