Bates P A, Robertson C D, Coombs G H
Department of Zoology, University of Glasgow, United Kingdom.
J Eukaryot Microbiol. 1994 May-Jun;41(3):199-203. doi: 10.1111/j.1550-7408.1994.tb01497.x.
The expression of cysteine proteinases by metacyclic promastigotes of Leishmania mexicana was investigated using gelatin polyacrylamide gel electrophoresis. Two prominent bands were detected which distinguished metacyclics from multiplicative promastigotes, lacking detectable cysteine proteinase activity, and amastigotes, with a distinct banding pattern composed of multiple enzymes. A correlation between relative activity of the metacyclic-specific bands and the prevalence of metacyclics was found both during the growth cycle in vitro as metacyclogenesis occurred, and by comparison of stationary phase populations from consecutive subpassages in vitro. Irreversible inhibition of the metacyclic activities using N-benzyloxycarbonyl-phenylalanyl-alanyl diazomethane did not inhibit metacyclic to amastigote transformation in vitro. These activities provide a useful biochemical marker for the metacyclic promastigotes of L. mexicana.
利用明胶聚丙烯酰胺凝胶电泳研究了墨西哥利什曼原虫循环前鞭毛体半胱氨酸蛋白酶的表达。检测到两条明显的条带，这将循环前鞭毛体与缺乏可检测半胱氨酸蛋白酶活性的增殖前鞭毛体以及具有由多种酶组成的独特条带模式的无鞭毛体区分开来。在体外生长周期中随着循环前鞭毛体的形成，以及通过比较体外连续传代的稳定期群体，发现循环前鞭毛体特异性条带的相对活性与循环前鞭毛体的流行率之间存在相关性。使用N-苄氧羰基-苯丙氨酰-丙氨酰重氮甲烷对循环前鞭毛体活性进行不可逆抑制，并未抑制体外循环前鞭毛体向无鞭毛体的转化。这些活性为墨西哥利什曼原虫的循环前鞭毛体提供了一个有用的生化标记。
