Identification of serine/threonine protein kinase secreted by Trichinella spiralis infective larvae
Identification of serine/threonine protein kinase secreted by Trichinella spiralis infective larvae
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DOI：
10.1016/s0166-6851(97)00145-x
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发表时间：
1997-12-01
影响因子：
1.5
通讯作者：
Selkirk, ME
中科院分区：
文献类型：
--
作者：
Arden, SR;Smith, AM;Selkirk, ME
通过外源性和内源性底物的磷酸化，在旋毛虫感染性幼虫的排泄/分泌（ES）产物中鉴定了丝氨酸/苏氨酸蛋白激酶活性。通过布雷菲德菌素A阻断蛋白激酶活性释放到培养基中，将蛋白激酶活性鉴定为真实的分泌产物。酶的活性是还原依赖性的，和一个面板的抑制剂的相对电阻表明，它不能很容易地分配到任何主要的记录亚家族的丝氨酸/苏氨酸蛋白激酶。ES产物中没有蛋白酪氨酸激酶活性的证据。通过SDS-PAGE，该隔室中的主要磷酸化蛋白质在50和55 kDa处分离，因此命名为pp 50/55。这些蛋白质主要含有磷酸丝氨酸，并出现代表差异糖基化的变体的35 kDa的多肽，通过添加三个和四个N-连接的寡糖，分别修改。通过SDS-PAGE分离后的自磷酸化测定在ES产物中鉴定了70和135 kDa的两种蛋白激酶。(C)1997年Elsevier Science B.V.
Serine/threonine protein kinase activity was identified in excretory/secretory (ES) products of Trichinella spiralis infective larvae, via phosphorylation of exogenous and endogenous substrates. Protein kinase activity was identified as an authentic secretory product via blockade of release into culture medium by brefeldin A. Enzyme activity was reductant-dependent, and the relative resistance to a panel of inhibitors suggested that it could not be readily assigned to any of the major documented subfamilies of serine/threonine protein kinases. There was no evidence for protein tyrosine kinase activity in ES products. The major phosphorylated proteins in this compartment resolved at 50 and 55 kDa by SDS-PAGE, and are therefore designated pp50/55. These proteins contained mainly phosphoserine, and appear to represent differentially glycosylated variants of a 35 kDa polypeptide, modified via the addition of three and four N-linked oligosaccharides, respectively. An autophosphorylation assay following separation by SDS-PAGE identified two protein kinases of 70 and 135 kDa in ES products. (C) 1997 Elsevier Science B.V.