Purification and properties of three new phospholipase A2 isoenzymes from Micropechis ikaheka venom.

Autor: Gao R; Venom and Toxin Research Programme, Department of Anatomy, National University of Singapore, Singapore., Kini RM, Li G, Luo R, Selvanayagam ZE, Gopalakrishnakone P
Jazyk: angličtina
Zdroj: Biochimica et biophysica acta [Biochim Biophys Acta] 2001 Feb 09; Vol. 1545 (1-2), pp. 30-40.
DOI: 10.1016/s0167-4838(00)00258-2
Abstrakt: Three new phospholipase A2 (PLA2) isoenzymes were purified from the Micropechis ikaheka venom by successive chromatographies. The homogeneity of them was accessed by capillary zone electrophoresis and mass spectrometry. Their N-terminal sequences showed high identity (94, 88 and 90, respectively) with MiPLA-1, a group IB PLA2 also from this venom. In addition, strong immuno-cross-reaction with anti-MiPLA-1 serum was observed. These results suggested that three newly purified PLA2 belonged to group IB. Beside enzymatic activity, they induced various pharmacological effects, including myotoxic, anticoagulant effects and insulin secretion stimulating effects. Our results indicated that enzymatic activity is essential for their myotoxic and anticoagulant effects. On the other hand, no direct correlation between their insulin secretion stimulating effect and enzymatic activity was observed, suggesting that they may stimulate insulin secretion through a non-enzymatic mechanism.
Databáze: MEDLINE