NANOASSAY FOR REALTIME MOLECULAR PROBING ABC TRANSPORTER

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 ABC转运蛋白是最大和最多样的膜蛋白超家族之一，存在于从细菌到人类的所有生物体中。 蛋白质是一种机械泵，它将三磷酸腺苷的水解作用与多种底物的吸收或输出结合起来，包括离子、糖、脂类、多肽或复杂的有机物质。 分子，与浓度梯度相反，跨越生物膜。1-5有趣的是，所有ABC转运蛋白共享四个核心区的共同组织：两个跨膜 结构域(TMD)和两个核苷酸结合域(NBD)，表明共同的进化起源，并暗示了类似的能量耦合机制。 ABC转运蛋白在医学上是相关的，因为它们可以导致微生物中的抗生素和抗真菌耐药性，以及癌症中对化疗的耐药性 细胞和许多真核细胞的功能障碍是严重疾病(例如囊性纤维化)的分子基础。5-7不幸的是，尽管进行了广泛的研究，但许多关于 ABC转运蛋白的分子机制和相互作用仍未得到解答。 在我们已经取得的重大进展和低温透射电子显微镜(Cryo-TEM)的最新发展的基础上，在这份修订的提案中，我们的目标是扩大我们的 最初提出的研究范围是利用低温透射电子显微镜、计算机重建和结构挖掘来解决多药细菌BMRA的结构和分子机制 属于ABC转运体超家族的转运体，通过与国家大分子成像中心(NCMI)(NCRR指定的生物医学研究资源)合作 结构生物学，请访问http://ncmi.bcm.tmc.edu/).

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. ABC transporters are one of the largest and most diverse super-families of membrane proteins found in all living organisms ranging from bacteria to humans.1-5 These membrane proteins act as mechanical pumps that couple ATP hydrolysis to either uptake or export of a wide diversity of substrates, including ions, sugars, lipids, peptides or complex organic molecules, against concentration gradients, across biological membranes.1-5 Interestingly, all ABC transporters share a common organization of a four core domains: two transmembrane domains (TMD) and two nucleotide-binding domains (NBD), indicating a common evolutionary origin and suggesting a similar mechanism of energy coupling. ABC transporters are medically relevant because they can be responsible for antibiotic and antifungal resistances in micro-organisms, resistance to chemotherapeutic treatments in cancer cells, and dysfunctions of many eukaryotic members are the molecular basis for severe sicknesses (e.g., cystic fibrosis).5-7 Unfortunately, despite extensive studies, many questions about the molecular mechanism and interactions of ABC transporters remain unanswered. Built upon the significant progress that we have made and the recent development of cryo-transmission electron microscopy (cryo-TEM), in this revised proposal, we aim to expand our original proposed research scope to use cryo-TEM, computer reconstruction and structure mining to solve the structure and molecular mechanism of BmrA, a multidrug bacterial transporter belonging to the ABC transporter superfamily, by collaborating with the National Center for Macromolecular Imaging (NCMI) (a NCRR designated Biomedical Research Resource for Structural Biology, at http://ncmi.bcm.tmc.edu/).