Determination of the amino acid sequence of a new phospholipase A(2) (MIDCA1) isolated from Micrurus dumerilii carinicauda venom.
A new Phospholipase A(2) (PLA(2)) from Micrurus dumerilii carinicauda venom was isolated and its primary structure determined. This new PLA(2) showed a low enzymatic activity when compared with other PLA(2)s and it is moderately basic with an isoelectric point of 8.0. Its amino acid sequence showed the presence of 120 amino acid residues and its sequence was: NLIQFLNMIQCTTPGREPLVAFANYGCYCGRGGSGTPVDELDRCCQVHDNCYDTAKKVFGCSPYFTMYSYDCSEGKLTCKDNNTKCKAAVCNCDRTAALCFAKAPYNDKNYKIDLTKRCQ. The structural model of MIDCA1, when compared with other strong neurotoxic PLA(2)s, such as Naja naja, showed significant differences in the beta-wing and neurotoxic sites, despite the high level of amino acid sequence similarity. These observations indicate a dissociation between the biological and catalytic activity of this new PLA(2), supporting the view that other regions of the protein are involved in the biological effects.
Belo
Cháriston A Dal
CA
Department of Pharmacology, School of Medical Sciences, State University of Campinas, Campinas, SP, Brazil.
Toyama
Marcos H
MH
Toyama
Daniela de O
Dde O
Marangoni
Sergio
S
Moreno
F B
FB
Cavada
Benildo S
BS
Fontana
Marcos D
MD
Hyslop
S
S
Carneiro
E M
EM
Boschero
Antonio C
AC
D000595:Amino Acid Sequence; D000818:Animals; D004546:Elapid Venoms / Q000201:enzymology*; D017815:Elapidae; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010741:Phospholipases A / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
D004546:Elapid Venoms; C053972:micrurus venom; D010741:Phospholipases A