Novel Leptospira interrogans protein Lsa32 is expressed during infection and binds laminin and plasminogen
Novel Leptospira interrogans protein Lsa32 is expressed during infection and binds laminin and plasminogen
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DOI：
10.1099/mic.0.000041
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发表时间：
2015-04-01
期刊：
影响因子：
2.8
通讯作者：
Nascimento, Ana L. T. O.
中科院分区：
文献类型：
--
作者：
Domingos, Renan F.;Fernandes, Luis G.;Nascimento, Ana L. T. O.
致病性钩端螺旋体是钩端螺旋体病的病原体，钩端螺旋体病是人类和兽医关注的威胁生命的疾病。正在寻求能够介导宿主-病原体相互作用的新型抗原。由于它们的位置，这些抗原有可能引发许多活动，包括免疫应答和粘附。本研究的重点是钩端螺旋体LIC 11089基因编码的一个假定蛋白质及其三个衍生片段：N-末端、中间和C-末端区域。利用表达载体pAE在大肠杆菌BL 21（SI）中克隆和表达了编码全长蛋白和片段的基因。重组蛋白和N端标记有六聚组氨酸的片段经金属亲和层析纯化。钩端螺旋体全长蛋白，命名为Lsa 32（钩端螺旋体表面粘附素，32 kDa），粘附层粘连蛋白，与C末端区域负责这种相互作用。Lsa 32以剂量依赖性方式与纤溶酶原结合，当提供激活剂时产生纤溶酶。此外，钩端螺旋体病血清样品中存在的抗体能够识别Lsa 32。蛋白酶K敏感性实验表明Lsa 32很可能是钩端螺旋体的一种新的表面蛋白。总之，我们的数据表明，这种多方面的蛋白质在感染过程中表达，并可能在宿主L中发挥作用。interaction interactions.
Pathogenic Leptospira is the aetiological agent of leptospirosis, a life-threatening disease of human and veterinary concern. The quest for novel antigens that could mediate host-pathogen interactions is being pursued. Owing to their location, these antigens have the potential to elicit numerous activities, including immune response and adhesion. This study focuses on a hypothetical protein of Leptospira, encoded by the gene LIC11089, and its three derived fragments: the N-terminal, intermediate and C terminus regions. The gene coding for the full-length protein and fragments was cloned and expressed in Escherichia coli BL21(SI) strain by using the expression vector pAE. The recombinant protein and fragments tagged with hexahistidine at the N terminus were purified by metal affinity chromatography. The leptospiral full-length protein, named Lsa32 (leptospiral surface adhesin, 32 kDa), adheres to laminin, with the C terminus region being responsible for this interaction. Lsa32 binds to plasminogen in a dose-dependent fashion, generating plasmin when an activator is provided. Moreover, antibodies present in leptospirosis serum samples were able to recognize Lsa32. Lsa32 is most likely a new surface protein of Leptospira, as revealed by proteinase K susceptibility. Altogether, our data suggest that this multifaceted protein is expressed during infection and may play a role in host-L. interrogans interactions.