Comparative analysis of Histophilus somni immunoglobulin-binding protein A (IbpA) with other fic domain-containing enzymes reveals differences in substrate and nucleotide specificities.
Comparative analysis of Histophilus somni immunoglobulin-binding protein A (IbpA) with other fic domain-containing enzymes reveals differences in substrate and nucleotide specificities.
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DOI：
10.1074/jbc.m111.227603
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发表时间：
2011-09-16
期刊：
影响因子：
--
通讯作者：
Worby CA
中科院分区：
文献类型：
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作者：
Mattoo S;Durrant E;Chen MJ;Xiao J;Lazar CS;Manning G;Dixon JE;Worby CA
最近发现了一个新的腺苷酰转移酶家族，其通过Fic结构域的存在来定义，该家族催化腺苷一磷酸（AMP）向Rho GTP酶的加成（Yarbrough，M. L.，李，Y.，金奇湖N.，Grishin，N.五、鲍尔，H。L.，和Orth，K.（2009）Science 323，269-272; Worby，C.一、马图，S.，克鲁格河P.，科尔贝湖B.，Koller，A.，门德斯，J.C.，Zekarias，B.，拉扎尔角，和狄克逊，J. E.（2009）Mol. Cell 34，93-103）。这种腺苷酸化事件通过阻止Rho GTP酶与其下游效应物结合而使其失活。我们报道了来自病原菌睡眠嗜组织菌的免疫球蛋白结合蛋白A（IbpA）的Fic结构域腺苷酸化哺乳动物Rho GTPases、RhoA、Rac 1和Cdc 42，从而诱导宿主细胞骨架崩溃，这使得H.睡眠会破坏肺泡屏障导致败血症IbpA介导的腺苷酸化发生在这些GTP酶的开关1区域中的功能关键的酪氨酸上。在这里，我们进行了详细的IbpA Fic 2结构域的表征，并将其活性与其他已知的Fic腺苷酸转移酶，VopS（弧菌外蛋白S）从细菌病原体副溶血性弧菌和人类蛋白HYPE（亨廷顿蛋白酵母相互作用蛋白E，也称为FicD）。在我们的分析中，我们还包括来自机会致病菌多杀性巴氏杆菌的分泌蛋白PfhB 2的Fic结构域。PfhB 2与IbpA共享一个共同的结构域架构，并包含两个Fic结构域。我们证明PfhB 2 Fic结构域也具有腺苷酰转移酶活性，其靶向Rho GTP酶的开关1酪氨酸。比较动力学和系统发育分析的IbpA-Fic 2与Fic结构域的PfhB 2，VopS，和HYPE揭示了重要方面的特异性Rho GTP酶和核苷酸的使用，并提供机制的见解，确定这些酶的核苷酸和底物的特异性。最后，我们比较Fic蛋白与其他已知的腺苷酸转移酶的进化谱系。
A new family of adenylyltransferases, defined by the presence of a Fic domain, was recently discovered to catalyze the addition of adenosine monophosphate (AMP) to Rho GTPases (Yarbrough, M. L., Li, Y., Kinch, L. N., Grishin, N. V., Ball, H. L., and Orth, K. (2009) Science 323, 269–272; Worby, C. A., Mattoo, S., Kruger, R. P., Corbeil, L. B., Koller, A., Mendez, J. C., Zekarias, B., Lazar, C., and Dixon, J. E. (2009) Mol. Cell 34, 93–103). This adenylylation event inactivates Rho GTPases by preventing them from binding to their downstream effectors. We reported that the Fic domain(s) of the immunoglobulin-binding protein A (IbpA) from the pathogenic bacterium Histophilus somni adenylylates mammalian Rho GTPases, RhoA, Rac1, and Cdc42, thereby inducing host cytoskeletal collapse, which allows H. somni to breach alveolar barriers and cause septicemia. The IbpA-mediated adenylylation occurs on a functionally critical tyrosine in the switch 1 region of these GTPases. Here, we conduct a detailed characterization of the IbpA Fic2 domain and compare its activity with other known Fic adenylyltransferases, VopS (Vibrio outer protein S) from the bacterial pathogen Vibrio parahaemolyticus and the human protein HYPE (huntingtin yeast interacting protein E; also called FicD). We also included the Fic domains of the secreted protein, PfhB2, from the opportunistic pathogen Pasteurella multocida, in our analysis. PfhB2 shares a common domain architecture with IbpA and contains two Fic domains. We demonstrate that the PfhB2 Fic domains also possess adenylyltransferase activity that targets the switch 1 tyrosine of Rho GTPases. Comparative kinetic and phylogenetic analyses of IbpA-Fic2 with the Fic domains of PfhB2, VopS, and HYPE reveal important aspects of their specificities for Rho GTPases and nucleotide usage and offer mechanistic insights for determining nucleotide and substrate specificities for these enzymes. Finally, we compare the evolutionary lineages of Fic proteins with those of other known adenylyltransferases.