Purification and primary structure of a myotoxic lysine-49 phospholipase A2 with low lipolytic activity from Trimeresurus gramineus venom.
Four acidic phospholipase A2 (PLA2) isozymes named PLA2-I, II, III and IV have previously been isolated from Trimeresurus gramineus (green habu snake) venom and sequenced [Oda et al. (1991) Toxicon 29, 157; Fukagawa et al. (1992) Toxicon 30, 1131; Fukagawa et al. (1993) Toxicon 31, 957]. They contain aspartate-49 which is known to bind Ca2+, essential for catalysis. In the present study, a basic PLA2 named PLA2-V containing lysine-49 was newly isolated from the same snake venom. Its isoelectric point was 9.4 and considerably higher than those (c. 4.5) of PLA2-I-IV. PLA2-V was 1.1% as active as PLA2-I toward egg-yolk emulsion but exhibited strong myotoxicity. The amino acid sequence of PLA2-V was determined by sequencing the S-carboxamidomethylated derivative and its peptide fragments produced by enzymatic (clostripain, chymotrypsin, Achromobacter protease I and Staphylococcus aureus V8 protease) cleavages. PLA2-V consists of 122 amino acid residues and is highly homologous (72-78%) to Lys-49 PLA2s so far isolated from Viperidae snake venoms but less homologous (52%) to PLA2-I. The presence of Asn-28, which is characteristic of Lys-49 PLA2s, was confirmed.
Nakai
M
M
Department of Chemistry, Kyushu University, Fukuoka, Japan.
Nakashima
K I
KI
Ogawa
T
T
Shimohigashi
Y
Y
Hattori
S
S
Chang
C C
CC
Ohno
M
M
D000595:Amino Acid Sequence; D000818:Animals; D003435:Crotalid Venoms / Q000737:chemistry* / Q000633:toxicity*; D054505:Group V Phospholipases A2; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000187:drug effects / Q000473:pathology*; D010741:Phospholipases A / Q000633:toxicity*; D054467:Phospholipases A2; D016415:Sequence Alignment
D003435:Crotalid Venoms; D010741:Phospholipases A; D054505:Group V Phospholipases A2; D054467:Phospholipases A2; C101424:phospholipase A2-V, Trimeresurus