墨西哥利什曼原虫：存在于特殊溶酶体中的无鞭毛体水解酶

Leishmania mexicana: amastigote hydrolases in unusual lysosomes.

作者信息

Pupkis M F, Tetley L, Coombs G H

出版信息

Exp Parasitol. 1986 Aug;62(1):29-39. doi: 10.1016/0014-4894(86)90005-6.

Abstract

Leishmania mexicana mexicana (M379) amastigotes were found to contain much higher activities than cultured promastigotes of five putative lysosomal enzymes: cysteine proteinase; arylsulfatase (EC 3.1.6.1); beta-glucuronidase (EC 3.2.1.31); DNase (EC 3.1.22.1), and RNase (EC 3.1.27.1). The release profiles of the first three of these enzymes from digitonin-permeabilized amastigotes suggests that they are located within organelles. Cytochemical staining for cysteine proteinase, using gold labeled antibodies and arylsulfatase, showed that both were present in large organelles previously named "megasomes." Comparative studies with L. mexicana amazonensis (LV78), L. donovani donovani (LV9), and L. major (LV39) revealed that L. mexicana amazonensis was similar to L. mexicana mexicana in possessing both high amastigote cysteine proteinase activity and large numbers of megasome organelles in amastigotes, whereas the other two species lacked both these features. The results suggest that the presence of numerous lysosome-like organelles in the amastigote is a characteristic of the L. mexicana group of parasites.

摘要

墨西哥利什曼原虫墨西哥亚种（M379）无鞭毛体被发现含有比培养的前鞭毛体更高的五种假定溶酶体酶活性：半胱氨酸蛋白酶；芳基硫酸酯酶（EC 3.1.6.1）；β-葡萄糖醛酸酶（EC 3.2.1.31）；脱氧核糖核酸酶（EC 3.1.22.1）和核糖核酸酶（EC 3.1.27.1）。这三种酶从洋地黄皂苷通透处理的无鞭毛体中的释放情况表明它们位于细胞器内。使用金标抗体对半胱氨酸蛋白酶和芳基硫酸酯酶进行细胞化学染色，结果显示二者都存在于先前命名为“巨大体”的大型细胞器中。对亚马逊利什曼原虫（LV78）、杜氏利什曼原虫杜氏亚种（LV9）和硕大利什曼原虫（LV39）的比较研究表明，亚马逊利什曼原虫与墨西哥利什曼原虫墨西哥亚种相似，无鞭毛体中半胱氨酸蛋白酶活性高且存在大量巨大体细胞器，而其他两个物种则缺乏这两个特征。结果表明，无鞭毛体中存在大量类似溶酶体的细胞器是墨西哥利什曼原虫属寄生虫的一个特征。