N49磷脂酶A2，蛇毒II组磷脂酶A2的一个独特亚组。

N49 phospholipase A2, a unique subgroup of snake venom group II phospholipase A2.

作者信息

Wei Ji-Fu, Wei Xiao-Long, Chen Qiu-Yu, Huang Tian, Qiao Li-Ya, Wang Wan-Yu, Xiong Yu-Liang, He Shao-Heng

机构信息

Allergy and Inflammation Research Institute, the Shantou University Medical College, Shantou, Guangdong, 515031, China.

出版信息

Biochim Biophys Acta. 2006 Mar;1760(3):462-71. doi: 10.1016/j.bbagen.2005.11.022. Epub 2005 Dec 27.

DOI:10.1016/j.bbagen.2005.11.022

PMID:16413680

Abstract

A novel phospholipase A2 (PLA2) with Asn at its site 49 was purified from the snake venom of Protobothrops mucrosquamatus by using SP-Sephadex C25, Superdex 75, Heparin-Sepharose (FF) and HPLC reverse-phage C18 chromatography and designated as TM-N49. It showed a molecular mass of 13.875 kDa on MALDI-TOF. TM-N49 does not possess enzymatic, hemolytic and hemorrhagic activities. It fails to induce platelet aggregation by itself, and does not inhibit the platelet aggregation induced by ADP. However, it exhibits potent myotoxic activity causing inflammatory cell infiltration, severe myoedema, myonecrosis and myolysis in the gastrocnemius muscles of BALB/c mice. Phylogenetic analysis found that that TM-N49 combined with two phospholipase A2s from Trimeresurus stejnegeri, TsR6 and CTs-R6 cluster into one group. Structural and functional analysis indicated that these phospholipase A2s are distinct from the other subgroups (D49 PLA2, S49 PLA2 and K49 PLA2) and represent a unique subgroup of snake venom group II PLA2, named N49 PLA2 subgroup.

摘要

通过使用SP-葡聚糖凝胶C25、Superdex 75、肝素-琼脂糖（FF）和HPLC反相C18色谱法，从菜花原矛头蝮蛇毒中纯化出一种在其49位位点含有天冬酰胺的新型磷脂酶A2（PLA2），并将其命名为TM-N49。基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）显示其分子量为13.875 kDa。TM-N49不具备酶活性、溶血活性和出血活性。它自身不能诱导血小板聚集，也不抑制ADP诱导的血小板聚集。然而，它表现出强大的肌毒性活性，可导致BALB/c小鼠腓肠肌出现炎性细胞浸润、严重的肌水肿、肌坏死和肌溶解。系统发育分析发现，TM-N49与来自竹叶青蛇的两种磷脂酶A2（TsR6和CTs-R6）聚为一组。结构和功能分析表明，这些磷脂酶A2与其他亚组（D49 PLA2、S49 PLA2和K49 PLA2）不同，代表蛇毒II型PLA2的一个独特亚组，命名为N49 PLA2亚组。