Structure and function of replicate natural bacterial communities

复制天然细菌群落的结构和功能

• 批准号: NE/F000286/1
• 负责人: Thomas Bell
• 金额: $ 12.37万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FF000286%2F1
• 关键词: Structure; function; replicate; natural; bacterial

We rely on the services that bacteria provide to digest our food, to breakdown pollutants, and to recycle the nutrients that are essential for maintaining natural ecosystems. Despite their importance, we are only beginning to understand how communities of bacteria operate. There is good reason why this is the case. The microbial world is perhaps the most complex and dynamic biological ecosystem, so experiments remain in their infancy. The proposed research will investigate fundamental questions in describing the factors that control the biodiversity (e.g. the number of species) and composition (i.e. the identity of the species) of bacterial communities and the consequences for ecosystem functioning. The approach that is used is to take a relatively simple but natural ecosystem that is easy to replicate. Such a system is provided by water-filled treeholes, which are 'natural microcosms' that I have used successfully in the past to uncover some fundamental patterns. In particular, this previous work has shown that larger treeholes contain more diverse bacterial communities. In addition, when bacteria are isolated from the treeholes and the communities are re-constructed in the laboratory, more diverse communities also have higher levels of ecosystem functioning (measured as the total respiration of the bacterial community). The current proposal follows from these exciting results by conducting a series of field experiments that attempt to discover the mechanisms that underlie the patterns. For example, one possible mechanism is that larger treeholes contain more diverse bacterial communities because colonisation by bacterial cells is more rapid into larger treeholes. The principle goal of the proposed research is to assess the degree to which altering the colonisation rate alters the final state of the bacterial community. This is done by explicitly manipulating colonisation rate in the field. I also propose to investigate whether the different communities that are thus created also differ in their level of ecosystem functioning. The results of such an experiment has far-reaching implications for microbial ecology by demonstrating how colonisation dynamics influence bacterial communities, a finding that would lie at the heart of our understanding of how microbial communities operate.

我们依靠细菌提供的服务来消化食物，分解污染物以及回收维持自然生态系统至关重要的养分。尽管它们的重要性，但我们才开始了解细菌社区的运作方式。有充分的理由是这种情况。微生物世界也许是最复杂，最动态的生物生态系统，因此实验仍处于起步阶段。拟议的研究将研究细菌群落的生物多样性（例如物种的数量）和组成（即物种身份）的基本问题，以及对生态系统功能的后果。所用的方法是采用一个易于复制的相对简单但自然的生态系统。这样的系统由水填充的树孔提供，这些树孔是我过去成功使用的“天然缩影”，以发现一些基本的模式。特别是，此前的这项工作表明，较大的树孔包含更多样化的细菌群落。此外，当从树孔中分离细菌并在实验室重新构建社区时，更多样化的社区也具有较高水平的生态系统功能（以细菌群落的总呼吸衡量）。当前的建议是从这些令人兴奋的结果中遵循的，通过进行一系列现场实验，试图发现模式下的机制。例如，一种可能的机制是，较大的树孔含有更多样化的细菌群落，因为细菌细胞的定殖更快地变成了较大的树孔。拟议研究的主要目标是评估改变殖民率的程度，改变细菌群落的最终状态。这是通过明确操纵现场的定植率来完成的。我还建议研究这样创建的不同社区是否在生态系统功能的水平上也有所不同。这种实验的结果通过证明殖民动力学如何影响细菌群落，对微生物生态学具有深远的影响，这一发现将是我们对微生物群落如何运作的理解的核心。