Molecular cloning and characterization of a 35.5-kilodalton lipoprotein of Treponema pallidum.
Molecular cloning and characterization of a 35.5-kilodalton lipoprotein of Treponema pallidum.
复制标题
梅毒螺旋体 35.5 千道尔顿脂蛋白的分子克隆和表征。
DOI：
10.1128/iai.59.4.1521-1528.1991
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发表时间：
1991
影响因子：
3.1
通讯作者：
Stamm,LV
中科院分区：
文献类型：
--
作者：
Hubbard,CL;Gherardini,FC;BassfordJr,PJ;Stamm,LV
表达35.5-kDa重组密螺旋体蛋白的克隆是从梅毒螺旋体街株14构建的基因组DNA文库中分离的。针对重组蛋白的多克隆抗血清与T.梅毒螺旋体是特异性致病密螺旋体。放射性标记的重组蛋白与[3 H]棕榈酸酯证明，它是脂质修饰。与其它最近鉴定的T. pallidum脂蛋白，35.5-kDa脂蛋白从T.用Triton X-114分级分离苍白球细胞，表明它是一个完整的膜蛋白。在脉冲追踪实验中，重组35.5-kDa脂蛋白从前体形式到较小成熟形式的加工不明显。然而，预处理大肠杆菌细胞表达的35.5 kDa的脂蛋白与蛋白质加工或易位的抑制剂揭示了存在一个更高的分子量的前体。转座子TnphoA的基因融合研究表明，在35.5 kDa的脂蛋白，促进35.5 kDa的脂蛋白-PhoA杂交的胞质外定位的出口信号的存在。
A clone expressing a 35.5-kDa recombinant treponemal protein was isolated from a genomic DNA library constructed from Treponema pallidum street strain 14. Polyclonal antiserum raised against the recombinant protein reacted with a corresponding native protein of comparable size in T. pallidum that is specific to the pathogenic treponemes. Radiolabeling of the recombinant protein with [3H]palmitate demonstrated that it is lipid modified. Like other recently characterized T. pallidum lipoproteins, the 35.5-kDa lipoprotein partitioned into the detergent phase from T. pallidum cells fractionated with Triton X-114, suggesting that it is an integral membrane protein. Processing of the recombinant 35.5-kDa lipoprotein from a precursor form to a smaller mature form was not evident in pulse-chase experiments. However, pretreatment of Escherichia coli cells expressing the 35.5-kDa lipoprotein with inhibitors of protein processing or translocation revealed the existence of a higher-molecular-mass precursor. Gene fusion studies with the transposon TnphoA demonstrated the presence of an export signal in the 35.5-kDa lipoprotein that promotes the extracytoplasmic localization of a 35.5-kDa lipoprotein-PhoA hybrid.