Zha Guo-Dong, Yang Dong-Hang, Wang Jing-Jing, Yang Bing, Yu Han-Shou
Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China.
Department of Agriculture, Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China.
Curr Microbiol. 2018 Jun;75(6):701-708. doi: 10.1007/s00284-018-1435-y. Epub 2018 Jan 23.
Spiroplasma melliferum is the causative agent of spiroplasmosis in honeybees. During infection, adhesion of spiroplasmas to the host cells through adhesion factors is a crucial step. In this study, we identified an adhesin-like protein (ALP609) in S. melliferum CH-1 and investigated its role in the infection. To determine whether ALP609 is an adhesion factor, we performed indirect immunofluorescence microscopy to visualize its adhesion properties. Subsequently, an infection model of S. melliferum CH-1 was established using primary midgut cells of Apis mellifera to examine the adhesion and invasion of spiroplasma using anti-ALP609 antibodies inhibition assays and competition assays with recombinant ALP609 in vitro. We found that anti-ALP609 antibodies could inhibit the adhesion and invasion of spiroplasma to the midgut cells of A. mellifera and reduce midgut cell invasion on increased exposure to recombinant ALP609. To the best of our knowledge, this is the first report identifying adhesion-related factors in S. melliferum. Our results suggested that ALP609 is an adhesin-like protein critical for invasion of S. melliferum CH-1 into midgut cells of A. mellifera.
蜜蜂螺旋体是蜜蜂螺旋体病的病原体。在感染过程中，螺旋体通过粘附因子与宿主细胞的粘附是一个关键步骤。在本研究中，我们在蜜蜂螺旋体CH-1中鉴定出一种类粘附素蛋白（ALP609），并研究了其在感染中的作用。为了确定ALP609是否为一种粘附因子，我们进行了间接免疫荧光显微镜检查以观察其粘附特性。随后，利用意大利蜜蜂的原代中肠细胞建立了蜜蜂螺旋体CH-1的感染模型，以通过抗ALP609抗体抑制试验和体外重组ALP609竞争试验来检测螺旋体的粘附和侵袭情况。我们发现抗ALP609抗体能够抑制螺旋体对意大利蜜蜂中肠细胞的粘附和侵袭，并且随着重组ALP609暴露量的增加，中肠细胞侵袭减少。据我们所知，这是首次报道在蜜蜂螺旋体中鉴定出与粘附相关的因子。我们的结果表明，ALP609是一种类粘附素蛋白，对蜜蜂螺旋体CH-1侵入意大利蜜蜂中肠细胞至关重要。
