title: Characterization and immunological comparison of isoenzymes of phospholipases A2 from snake venoms of different genera and families.
abstract: Phospholipases A2 (PLA2) were isolated and purified from the Taiwan cobra (Naja naja atra) and several snake species of the same or different genera by semipreparative cation-exchange and reversed-phase HPLC. They were shown to possess different enzymatic activity toward the synthetic substrate L-alpha-lecithin by the fatty-acid titration method. The immunological cross-reactivity of these structurally similar isotoxins was investigated using immunodiffusion, precipitin reaction and enzyme-linked immunosorbent assay (ELISA). PLA2 from the venoms of the same species such as the Taiwan cobra (Naja naja atra) and the Indian cobra (Naja naja naja) showed a high degree of antigenic resemblance whereas no immunoreactivity was observed among those PLA2 from different genera. Quantitative immunoreactivity assays by ELISA revealed the partial cross-reactivity between the antibody against PLA2 of Taiwan cobra and those isoenzymes from snakes of remotely-related species. The immunological relatedness between PLA2 of the representative snake species of different genera and families is shown to be correlated with the extent of sequence homology among these enzymes.
authors.affiliation: Institute of Biochemical Sciences, National Taiwan University, Taipei.
authors.forename: S H
authors.initials: SH
authors.lastname: Chiou
authors.forename: L Y
authors.initials: LY
authors.lastname: Chuang
authors.forename: C C
authors.initials: CC
authors.lastname: Chang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003429:Cross Reactions; D004546:Elapid Venoms / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005779:Immunodiffusion; D007527:Isoenzymes / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism; D010741:Phospholipases A / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D054467:Phospholipases A2; D012910:Snake Venoms / Q000201:enzymology*; D013045:Species Specificity
chemical_list: D000906:Antibodies; D004546:Elapid Venoms; D007527:Isoenzymes; D010713:Phosphatidylcholines; D012910:Snake Venoms; D010741:Phospholipases A; D054467:Phospholipases A2