Ribosome Complexes With Antibiotics And Macromolecules

核糖体催化的、信使RNA指导的蛋白质合成的机制在所有生物体中基本上是相同的，出于许多原因，充分理解它是很重要的。首先，蛋白质合成是所有生物体的主要代谢活动。第二，可能涉及新的RNA依赖性酶学。第三，由于许多抗生素都是针对细菌核糖体的，因此了解核糖体翻译阶段的细节可能具有重要的临床意义。由于缺乏原子分辨率的信息核糖体构象严重限制了这一领域的调查多年的进展。本文提出的工作重点是确定核糖体的结构及其与抗生素形成的复合物，以及通过X射线晶体学与之相互作用的大分子。 将与R.A.合作开展四个项目。或多或少的施泰兹。首先，解决来自Haloarcula marismortui的核糖体大亚基的晶体结构的努力已经在进行中，将得出结论。现有的晶体可用于超过A分辨率的计算，并且结构的可解释的电子密度图今天可以计算到5 A分辨率。其次，将制备核糖体小亚基结构域的晶体，希望以比使用目前可用的完整小亚基晶体可获得的分辨率高得多的分辨率获得关于该亚基构象的信息。第三，将制定一个计划，其目标是确定从H的核糖体大亚基分离的蛋白质的晶体结构。marismortui，或其他古细菌物种，以方便解释的电子密度图的H。maris mortui 50核糖体亚基的研究。第四，将从真核生物中制备核糖体晶体，酵母中的核糖体是第一个目标。

The mechanism of ribosome-catalyzed, messenger RNA-directed protein synthesis is fundamentally the same in all organisms, and it is important that it be fully understood for many reasons. First, protein synthesis is a major metabolic activity in all organisms. Second, novel RNA-dependent enzymology may be involved. Third, because so many antibiotics target bacterial ribosomes, an understanding of the details of the ribosomal phase of translation may have significant clinical implications. Since lack of atomic resolution information about ribosome conformation has serious limited progress in this area of inquiry for many years. The focus of the work proposed here is the determination of the structure of the ribosome and the complexes it forms with antibiotics and the macromolecules with which it interacts by X-ray crystallography. Four projects will be undertaken all in collaboration with R.A. Steitz to a greater or lesser extent. First, the effort to solve crystal structure of the large ribosomal subunit from Haloarcula marismortui, which is already well underway, will be brought to a conclusion. The crystals available diffract past A resolution, and interpretable electron density maps of the structure can be computed today to 5 A resolution. Second, crystals will be prepared of domains of the small ribosomal subunit, in hopes of obtaining information about the conformation of that subunit at resolutions significantly higher than those accessible using the crystals of intact small subunits currently available. Third, a program will be instituted the objectives of which is the determination of the crystal structures of isolated proteins from the large ribosomal subunit of H. marismortui, or of other archael species, to facilitate the interpretation of the electron density maps of the H. maris mortui 50 ribosomal subunit that are becoming available. Fourth, crystals will be prepared of ribosomes from eukaryotic species, with the ribosomes form yeast being the first objective.