Investigations of the link between the bacterial cytoskeleton and N-cycling in the Rhizobium-legume symbiosis

固氮作用是将大气中的氮转化为氨，是地球化学氮循环的一部分。根瘤菌存在于土壤中，可以与豆科植物的根部形成共生关系，在那里细菌固定氮并为豆科植物提供氨的直接来源。根瘤菌-豆科植物共生对农业实践具有重要影响，大大减少了氮肥使用所产生的污染。虽然细菌的生长已经研究了很多年，但对根瘤菌进入其同源豌豆植物的生长机制知之甚少。我们将研究知之甚少的极性生长机制及其与根瘤菌目之间的N-循环的联系，并通过分析英国几个地点的农田土壤样品来监测极性蛋白组装体的多样性。与PGRO（加工者和种植者研究组织）合作，将收集和分析细菌样本。微生物分子生物学技术，包括敲除突变和荧光蛋白融合的产生将被用来研究极性蛋白组装体。最后，将测试突变体与豌豆植物建立成功共生的能力。

Nitrogen fixation is the conversion of atmospheric nitrogen into ammonia and is a part of biogeochemical nitrogen cycling. Rhizobium bacteria are found in soil and can form a symbiosis with the roots of legume plants, where the bacteria fix nitrogen and provide a direct source of ammonia to the legume. The Rhizobium-legume symbiosis has significant impact on agricultural practices greatly reducing pollution generated by the use of nitrogen fertilisers. Although bacterial growth has been studied for many years, very little is known about the mechanism of growth during the entry of Rhizobium bacteria into their cognate pea-plant. We will study the poorly understood mechanism of polar growth and its link to N-cycling amongst Rhizobiales and monitor the diversity of polar protein assemblies by analysing soil samples from crop-fields at several UK locations. In collaboration with PGRO (Processors and Growers Research Organisation) the bacterial samples will be collected and analysed. Microbial molecular biology technologies including the generation of knockout mutations and fluorescent protein fusions will be used to study the polar protein assemblies. Finally, mutants will be tested for their ability to establish successful symbiosis with pea plants.