Structure, Assembly, and Function of Outer Membrane Proteins

项目摘要 膜蛋白约占所有原核和真核蛋白质组的30%。 它们负责离子传导、化学运输、能量转换、信号传递 转导、激素和光接收、细胞粘附和许多其它功能。 结构生物学长期以来的原则是，要充分了解结构的功能， 生物分子的结构必须已知。膜蛋白也不例外， 请注意。然而，旨在阐明其结构的科学却远远落后 类似的可溶性蛋白质科学，主要是出于技术原因。的目标 本申请提出的研究是两方面的：（1）推进溶液NMR 光谱学作为膜蛋白结构测定的方法，和（2） 进一步了解四种原核外膜蛋白的功能 通过溶液核磁共振研究它们的结构。特别是：来自E.大肠杆菌主要 将用作NMR方法开发的模型膜蛋白，用于研究 脂质-蛋白质相互作用，并用于检查脂质中膜蛋白的稳定性 双分子层; OmpG来自E.大肠杆菌正成为生物传感器的首选生物纳米孔 发展和核磁共振将被用来了解机制，通过它门 OprG和OprH是两种外膜蛋白 来自铜绿假单胞菌，其导致严重的抗生素耐药性 将通过确定它们的结构和研究来研究这种微生物的结构。 它们的功能。

PROJECT SUMMARY Membrane proteins constitute about 30 % of all prokaryotic and eukaryotic proteomes. They are responsible for ion conduction, chemical transport, energy conversion, signal transduction, hormone- and photo-reception, cell adhesion, and many other functions. The long-held tenet of structural biology is that to fully understand the function of biomolecules their structure must be known. Membrane proteins are no exception in this regard. However, the science aimed at elucidating their structures has lagged far behind similar science on soluble proteins, mostly for technical reasons. The goal of the research proposed in this application is two-fold: (1) to advance solution NMR spectroscopy as a method for structure determination of membrane proteins and (2) to further the understanding of the functions of four prokaryotic outer membrane proteins by studying their structures by solution NMR. Specifically: OmpA from E. coli primarily will be used as a model membrane protein for NMR methods development, for studying lipid-protein interactions, and for examining the stability of membrane proteins in lipid bilayers; OmpG from E. coli is becoming the preferred biological nanopore for biosensor development and NMR will be used to understand the mechanism, by which it gates from the open to the closed state; and OprG and OprH are two outer membrane proteins from Pseudomonas aeruginosa, whose contributions to the severe antibiotic resistance of this microorganism will be investigated by determining their structures and studying their functions.