Isolation and biochemical characterization of a gamma-type phospholipase A(2) inhibitor from Macropisthodon rudis snake serum

摘要

A novel phospholipaseA(2) (PLA(2)) inhibitory protein (PLI) was purified from the serum of Macropisthodon rudis, a non-venomous snake mainly found in southern China. The molecular mass of the purified PLI was 160 kDa as determined by Superdex 200HR; however, the PLI protein had only one subunit of 25.4 kDa as determined by 12% SDS-PAGE, indicating an oligomeric protein. PLI cDNA obtained by PCR from the liver of Macropisthodon rudis, revealed 549 bps coding for a mature protein of 183 amino acid residues. Based on an amino acid sequence alignment with venomous and non -venomous snakes, this inhibitor was determined to be in the gamma type family of PLI. In vitro experiments showed that PLl gamma inhibited enzymatic, inflammatory, and antibacterial activities of snake venom PLA2 isolated from Agkistrodon acutus. (C) 2016 Elsevier Ltd. All rights reserved.