TARGETING AND ASSEMBLY OF E COLI OUTER MEMBRANE PROTEINS

描述：蛋白质的靶向和组装是基本的 生物过程。 在许多情况下，靶向信号由下式定义： 小的线性序列延伸，例如存在于氨基处的那些 在细菌和真核生物中分泌蛋白质的末端。 虽然这些 大肠杆菌中的序列帮助蛋白质离开细胞质，它们 不能确定分泌蛋白在细胞内的最终位置。 细胞质外区室：周质和外膜。 该项目的结果强调， 对于外膜蛋白， 中间体的 这些中间体的折叠状态由 分子的内在性质及其与其他分子的相互作用 细胞组分包括伴侣蛋白和脂多糖， 其专门位于外膜中。 新的遗传 本项目中概述的方法将有助于揭示 基因内信息，并提供更好的了解动态 靶向过程中各种细胞成分之间的相互作用， 外膜蛋白的组装。 因为这些人之间的相互作用 成分和蛋白质发生在所有生物膜，结果 应该有广泛的兴趣。 OmpF、OmpC和LamB将用作模型蛋白。 这些蛋白质作为 噬菌体的受体并形成允许扩散的通道 水溶性溶质。 OmpF和LamB的三维结构 虽然已经解决，但可以更好地了解 这些蛋白质的结构-功能关系，揭示了很少的光如何 他们到达目的地。 该项目的长期目标是了解 外膜蛋白和外膜的分子结构。 这些目标将通过应用遗传 这些方法是可行的，并且已经产生了重要和新的成果。 见解.

DESCRIPTION: The targeting and assembly of proteins are fundamental biological processes. In many instances, the targeting signal is defined by small liner stretches of sequence such as those present at the amino terminal end of secreted proteins in bacteria and eukaryotes. While these sequences in Escherichia coli assist proteins in exiting the cytoplasm, they do not determine the final location of secreted proteins within the extracytoplasmic compartments: periplasm and outer membrane. Results from this project have emphasized the view that the targeting signal for outer membrane proteins resides within the partially folded intermediates. The folding states of these intermediates are guided by the intrinsic properties of the molecule and its interactions with other cellular components including chaperone proteins and lipopolysaccharide, which is exclusively localized in the outer membrane. Novel genetic approaches outlined in this project will assist in revealing the nature of intragenic information and provide a better understanding of the dynamic interactions between various cellular components during the targeting and assembly of outer membrane proteins. Because interactions between lipidic components and proteins occur in all biological membranes, the results should have broad general interest. OmpF, OmpC and LamB will be used as model proteins. These proteins serve as the receptor for bacteriophages and form channels that allow the diffusion of water soluble solutes. Three-dimensional structures of OmpF and LamB have been resolved which, while permitting a better understanding of the structure-function relationship of these proteins, shed little light on how they reach their destination. The long term goals of this project are to understand the biogenesis of outer membrane proteins and molecular architecture of the outer membrane. These objectives will be achieved through the application of genetic approaches that are feasible and have already yielded important and new insights.