Rhizobium bacteroid development

根瘤菌类菌发育

基本信息

批准号：
BB/J007749/2
负责人：
Philip Poole
金额：
$ 38万
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：
2013
资助国家：
英国
起止时间：
2013 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FJ007749%2F2
关键词：
Rhizobium bacteroid development

项目摘要

Bacteria are simple single celled organisms that lack the membrane bound structures found in higher cells of plants and animals. However, while bacteria may have a less complex cellular organisation they carry out a huge range of chemical reactions not found in plants and animals. Bacteria are responsible for the cycling of many nutrients such as N2 (N2 is also known as nitrogen gas and consists of two nitrogen atoms bound by a strong triple bond), which is a very inert atmospheric gas. N2 makes up 78% of the atmosphere but is very unreactive and cannot be used directly as a source of nitrogen, which is needed for amino acid, protein and DNA synthesis. However, a small number of bacteria can reduce (add hydrogen) to N2 and convert it into ammonia (NH3), which is readily incorporated into amino acids and then all the other building blocks of life, by a wide range of organisms including bacteria and plants. In many parts of the world the limitation to growth of plants, which in turn support animal life, is the supply of nitrogen as ammonia or related compounds. Since up to 65% of available nitrogen (eg ammonia) comes from bacteria this makes them essential for life on earth. Within the bacteria, most of the nitrogen is actually produced by one family known as the Rhizobiacea. This remarkable group of bacteria form a symbiotic association (both partners benefit) with plants of the legume family, that results in the formation of root nodules (on pea plants these are 2-3 mm bulbs that can easily be seen by pulling up a plant and inspecting its roots). The rhizobia are held inside the nodules where the plant provides them with an ideal environment (low O2 and lots of energy) in which they can reduce N2 to ammonia. The ammonia is supplied to the plant as its nitrogen source so this is why this is known as a symbiotic interaction. It means that the plant does need any nitrogen added to the the soil and enables rapid growth. The purpose of this research is to understand how the bacteria develop inside legume root nodules. In this reserach we use peas as our model legume. Questions include how do the bacteria grow inside plants and what factors control this process? How do the bacteria know when to switch on N2 fixation?

细菌是简单的单细胞生物，缺乏在动植物的较高细胞中发现的膜结构。但是，尽管细菌可能具有不太复杂的细胞组织，但它们在动植物中进行了大量的化学反应。细菌是导致许多营养素（N2）（N2也称为氮气）循环的原因，它是由两个由强三键结合的氮原子组成的），这是一种非常惰性的大气气体。 N2占大气的78％，但没有反应性，不能直接用作氨基酸，蛋白质和DNA合成所需的氮来源。但是，少数细菌可以将氢化（NH3）降低（添加氢），并通过包括细菌和植物在内的广泛的生物体，很容易地掺入氨基酸，然后将其纳入氨基酸，然后将其纳入氨基酸。在世界许多地方，植物生长的局限性又支持动物的生命，是氮作为氨或相关化合物的供应。由于多达65％的可用氮（例如氨）来自细菌，因此使其对地球生命至关重要。在细菌中，大多数氮实际上是由一个称为Rhizobiacea的家族产生的。这一引人注目的细菌与豆科植物的植物形成了共生缔合（两者都受益），从而形成了根结节（在豌豆植物上，这些是2-3毫米鳞茎，可以通过拉起植物并检查其根部可以轻松地看到它们）。根瘤菌在结节内部固定在植物为它们提供理想的环境（低O2和大量能量）的结节内，其中它们可以将N2降低至氨。将氨作为其氮源提供给植物，因此这就是为什么这被称为共生相互作用的原因。这意味着该植物确实需要在土壤中添加任何氮，并可以快速生长。这项研究的目的是了解细菌在豆科植物根结节内如何发展。在此研究中，我们将豌豆作为我们的模型豆类。问题包括细菌如何在植物内生长，哪些因素控制了这一过程？细菌如何知道何时打开N2固定？

项目成果

期刊论文数量（10）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Arabinose and protocatechuate catabolism genes are important for growth of Rhizobium leguminosarum biovar viciae in the pea rhizosphere.

DOI：
10.1007/s11104-015-2389-5
发表时间：
2015
期刊：
PLANT AND SOIL
影响因子：
4.9
作者：
Garcia-Fraile, Paula;Seaman, Jonathan C.;Karunakaran, Ramakrishnan;Edwards, Anne;Poole, Philip S.;Downie, J. Allan
通讯作者：
Downie, J. Allan

Rhizobial Chemotaxis and Motility Systems at Work in the Soil.