Functional analyses of bacterial nucleotide transport proteins

细菌核苷酸转运蛋白的功能分析

• 批准号: 87529176
• 负责人: Dr. Ilka Haferkamp
• 金额: --
• 依托单位: Fachgebiet Pflanzenphysiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/87529176?language=en
• 关键词: Functional; analyses; bacterial; nucleotide; transport

Exploitation of host derived nucleotides and “energy parasitism” are essential common features of certain obligate intracellular (pathogenic) bacteria. Although various nucleotide transport proteins (NTT) have been characterized so far, fundamental questions concerning biochemical properties and structure/function relationships remained unaddressed. Our very recent analyses provided evidence for phosphate as a previously unidentified substrate of the ATP/ADP transporter PamNTT1 from the amoeba symbiont Protochlamydia amoebophila. Interestingly, an NTT driven phosphate transport would make a specialized phosphate carrier unnecessary and would explain why the long lasting search for the corresponding protein in intracellular living bacteria failed. In this study, we will perform a sophisticated biochemical analysis of the functionally different nucleotide transporters PamNTT1-5 and also of a representative ATP/ADP transporter from Rickettsiales which aims to clarify whether bacterial phosphate transport is (i) restricted to PamNTT1 or (ii) a typical feature of “energy parasitism” or (iii) a general principle in bacterial nucleotide transport. Furthermore, by the help of selected mutant proteins we aim to identify amino acids essential for nucleotide and phosphate transport.

利用宿主衍生的核苷酸和“能量寄生”是某些专性细胞内（致病）细菌的基本共同特征。虽然各种核苷酸转运蛋白（NTT）的特点到目前为止，有关生化特性和结构/功能关系的基本问题仍然没有得到解决。我们最近的分析提供了证据磷酸盐作为一个以前未确定的底物的ATP/ADP转运蛋白PamNTT 1从阿米巴共生体Protochlamydia amoebophila。有趣的是，NTT驱动的磷酸盐转运将使专门的磷酸盐载体变得不必要，并将解释为什么在细胞内活细菌中长期寻找相应蛋白质失败。在这项研究中，我们将进行一个复杂的生化分析的功能不同的核苷酸转运蛋白PamNTT 1 -5，也是一个代表性的ATP/ADP转运从立克次氏体，其目的是澄清细菌磷酸盐转运是（i）限制到PamNTT 1或（ii）一个典型的功能“能量寄生”或（iii）在细菌核苷酸转运的一般原则。此外，通过选择的突变蛋白的帮助下，我们的目标是确定核苷酸和磷酸盐转运所必需的氨基酸。