Ethanolamine utilizing bacterial microcompartments in host cells

项目摘要/摘要 在宿主环境中，乙醇胺(EA)可以作为碳、氮和/或能量的关键来源 编码EA分解代谢所必需的EA利用(EUT)基因的细菌。在许多病原体中 在已有的研究中，EA的利用对生存和致病性有积极的贡献。许多EA- 利用细菌还编码形成一种类似细胞器的蛋白质结合结构，称为细菌 发生EA分解代谢的微室(BMC)。目前，知识严重匮乏。 关于EA是如何产生的，以及在宿主细胞中何时何地利用EA的分解代谢。我们的长期目标是 了解EA在细菌中的利用。本申请的目的是阐明EUT BMC中的关键差距 动力学和EA分解代谢，重点放在细胞内环境。中心假设是 骨髓细胞聚集在宿主细胞吞噬小体内，通过PEA的分解代谢产生EA。具体目标#1将 确定在宿主细胞内形成骨髓细胞的时间和地点。单核细胞增多性乳杆菌是一种天然的胞内细菌。 从吞噬细胞的吞噬小体中逃脱，在宿主细胞细胞质中复制的病原体。基于强大的 初步数据推测，EUT BMCs形成于吞噬小体中。具体目标#2将阐明 EA是如何从磷脂来源中衍生出来的。假设是利用EA的细菌通过 分解PEA，因此编码PEA分解代谢所需的酶。候选基因是 其中一种的鉴定和初步研究证明了它在EA利用中的作用。总体而言，这项研究将 显著影响骨髓基质细胞生物学、EA利用和宿主-病原体相互作用等领域。另外， 因为它将识别产生EA所必需的细菌酶，EA是抗菌药物的潜在靶标 发展将是精准的。拟议中的研究在概念上是创新的，因为它试图破译 宿主细胞中的BMC动态变化。此外，它还将研究EA如何在宿主细胞中可用，这是一个未经询问的问题 这个问题在很大程度上已经被实地掩盖了。

PROJECT SUMMARY/ABSTRACT Within host environments, ethanolamine (EA) can serve as a key source of carbon, nitrogen and/or energy for those bacteria that encode the EA-utilizing (eut) genes necessary for its catabolism. In many of the pathogens in which it has been studied, EA utilization positively contributes to survival and pathogenicity. Many EA- utilizing bacteria also encode for the formation of an organelle-like, protein-bound structure called a bacterial microcompartment (BMC) in which EA catabolism takes place. Currently, there is a critical lack of knowledge regarding how EA is derived and when and where EA catabolism is utilized in host cells. Our long-term goal is to understand EA utilization in bacteria. The objective of this application is to elucidate key gaps in Eut BMC dynamics and EA catabolism with a focus on the intracellular environment. The central hypothesis is that BMCs assemble within the host cell phagosome and derive EA by catabolism of PEA. Specific Aim #1 will identify when and where BMCs are formed within host cells. L. monocytogenes is a natural intracellular pathogen that escapes the phagocytic phagosome to replicate in the host cell cytoplasm. Based on strong preliminary data, it is postulated that the Eut BMCs form in the phagosome. Specific Aim #2 will elucidate how EA is derived from phospholipid sources. The hypothesis is that bacteria that utilize EA obtain it by breakdown of PEA and therefore encode the enzymes necessary for PEA catabolism. Candidate genes were identified and preliminary studies of one demonstrated its role in EA utilization. Overall, this study will significantly impact the fields of BMC biology, EA utilization and host-pathogen interactions. Additionally, because it will identify the bacterial enzymes necessary to generate EA, potential targets for antimicrobial development will be pinpointed. The proposed research is conceptually innovative in that it seeks to decipher BMC dynamics in host cells. Moreover, it will examine how EA becomes available in host cells, an unasked question that has largely been swept under the rug by the field.