磷脂酶C从巴西利什曼原虫释放后，糖基磷脂酰肌醇锚定膜蛋白酶的激活。

Activation of the glycosylphosphatidylinositol-anchored membrane proteinase upon release from Herpetomonas samuelpessoai by phospholipase C.

作者信息

dos Santos André Luis Souza, Abreu Celina Monteiro, Alviano Celuta Sales, de Araújo Soares Rosangela Maria

机构信息

Departamento de Microbiologia Geral, Instituto de Microbiologia Prof. Paulo de Góes, Centro de Ciências da Saúde, Bloco I, Universidade do Brasil (UFRJ), Ilha do Fundão, 21941-590, Rio de Janeiro, RJ, Brazil.

出版信息

Curr Microbiol. 2002 Oct;45(4):293-8. doi: 10.1007/s00284-002-3752-3.

DOI:10.1007/s00284-002-3752-3

PMID:12192529

Abstract

We have analyzed the effects of exogenous phospholipase C (PLC) on the cell-surface polypeptides and proteinases of Herpetomonas samuelpessoai grown in chemically defined conditions by SDS-PAGE gels. Live parasites treated with PLC released into the extracellular medium a complex profile of glycosylphosphatidylinositol (GPI)-anchored polypeptides ranging from 15 to 100 kDa, some of them with proteolytic activity. Two major metalloproteinases with apparent molecular masses of 63 and 115 kDa were observed after PLC hydrolysis. Interestingly, only the PLC-released soluble form of the 115-kDa metalloenzyme, and not the membrane-anchored form, displayed proteolytic activity, demonstrating that cleavage of the GPI anchor can lead to enzymatic activation.

摘要

我们通过SDS-PAGE凝胶分析了外源性磷脂酶C（PLC）对在化学成分确定的条件下生长的塞缪尔佩索阿赫氏鞭毛虫细胞表面多肽和蛋白酶的影响。用PLC处理的活寄生虫向细胞外培养基中释放了一系列复杂的糖基磷脂酰肌醇（GPI）锚定多肽，分子量范围为15至100 kDa，其中一些具有蛋白水解活性。PLC水解后观察到两种主要的金属蛋白酶，表观分子量分别为63 kDa和115 kDa。有趣的是，只有PLC释放的115 kDa金属酶的可溶性形式具有蛋白水解活性，而膜锚定形式则没有，这表明GPI锚的切割可导致酶的激活。