My. Ahn et al., CHARACTERIZATION AND CYTOTOXICITY OF L-AMINO-ACID OXIDASE FROM THE VENOM OF KING COBRA (OPHIOPHAGUS HANNAH), International journal of biochemistry & cell biology, 29(6), 1997, pp. 911-919
The aim of this project was to determine the cytotoxic components from
the venom of king cobra, Ophiophagus hannah. Venom was purified by a
combination of gel-filtration, ion-exchange and reversed-phase chromat
ographic steps. The biochemical properties of the cytotoxic component
were consistent with those of L-amino acid oxidase, The molecular,weig
ht of the enzyme was estimated to be 150 000 by gel filtration and 70
000 under the denaturing conditions of SDS-PAGE, indicating a dimer, I
t has an isoelectric point of 4.5 and is a glycoprotein. The N-termina
l sequence of L-amino acid oxidase from the king cobra venom was deter
mined to be SVINLEESFQEPEYE. The cytotoxicity of L-amino acid oxidase
was observed in stomach cancer, murine melanoma, fibrosarcoma, colorec
tal cancer and Chinese hamster ovary cell lines, Cytotoxicity resulted
in the loss of ability in attachment and inhibition of cell prolifera
tion, The cytotoxic protein decreased the level of cell proliferation
by 74% according to [H-3]thymidine uptake assay. The mechanism of enzy
me action mag be related to the inhibition of thymidine incorporation
and an interaction with DNA. (C) 1997 Elsevier Science Ltd.