Inactivation of phospholipase A2 and metalloproteinase from Crotalus atrox venom by direct current.
To achieve our aim of understanding the interactions between direct current and enzymes in solution, we exposed reconstituted Crotalus atrox venom to direct electric current by immersing two platinum thread electrodes connected to a voltage generator (between 0 and 8 V) into a reaction mixture for a few seconds. Then, we assayed the residual activity of phospholipases A(2) (PLA(2)),metalloproteinases, and phosphodiesterases, abundant in crotaline snake venoms and relevant in the pathophysiology of envenomation, characterized by hemorrhage, pain, and tissue damage. C. atrox venom phospholipase A(2) and metalloproteinases were consistently and irreversibly inactivated by direct current (between 0 and 0.7 mA) exposure. In contrast, C. atrox venom phosphodiesterases were not affected. Total protein content and temperature of the sample remained the same. Secretory pancreatic phospholipase A(2), homologue to snake venom phospholipases A(2), was also inactivated by direct current treatment. In order to understand the structural reasoning behind PLA(2) inactivation, circular dichroism measurements were conducted on homogeneous commercial pancreatic phospholipase A(2), and it was found that the enzyme undergoes structural alterations upon direct current exposure.
Panfoli
Isabella
I
Department of Biology, University of Genoa, V. le Bendetto XV, 3, 16132 Genova, Italy. Isabella.Panfoli@unige.it
Ravera
Silvia
S
Calzia
Daniela
D
Dazzi
Elisa
E
Gandolfo
Simona
S
Pepe
Isidoro M
IM
Morelli
Alessandro
A
D000818:Animals; D002942:Circular Dichroism; D003435:Crotalid Venoms / Q000201:enzymology*; D017839:Crotalus; D004560:Electricity; D004789:Enzyme Activation; D054513:Group IV Phospholipases A2 / Q000378:metabolism*; D045726:Metalloproteases / Q000378:metabolism*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D013552:Swine
D003435:Crotalid Venoms; D054513:Group IV Phospholipases A2; D010727:Phosphoric Diester Hydrolases; D045726:Metalloproteases