Purification and characterization of phenoloxidase from the hemocytes of Eurygaster integriceps (Hemiptera: Scutelleridae).
Insects protect themselves from microbial invaders by two main immune activities, namely the cellular and humoral reactions. Phenoloxidases are oxidative enzymes that have an important role in both cell-mediated and humoral immunity. In this study, the purification and biochemical characterization of a phenoloxidase from the hemocytes of the Sunn pest Eurygaster integriceps Puton (Hemiptera: Scutelleridae) were carried out. After the final purification step, the enzyme was purified 7.31-fold with a recovery of 3.94% and a specific activity of 4.95U/mg protein. Results of the biochemical characterization showed that the purified phenoloxidase has a maximum activity at pH 6 and at 30-35°C and is stable for 24-36h. Divalent cations such as Ca(2+) and Cu(2+) significantly increased the enzymatic activity and synthetic inhibitors such as phenylthiourea significantly decreased it. The purified phenoloxidase has a molecular mass of 22kDa. The current paper represents a further step towards the characterization of humoral immunity of E. integriceps in order to develop new strategies for the biological control of the Sunn pest.
Zibaee
Arash
A
Department of Plant Protection, College of Agriculture, University of Guilan-Rasht, 41635-1314, Iran. arash.zibaee@gmx.com
Bandani
Ali Reza
AR
Malagoli
Davide
D
D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D006430:Hemiptera / Q000201:enzymology*; D006434:Hemocytes / Q000201:enzymology*; D008970:Molecular Weight; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism*; D010670:Phenylthiourea / Q000494:pharmacology; D013045:Species Specificity; D013329:Structure-Activity Relationship
D010670:Phenylthiourea; D014442:Monophenol Monooxygenase