Dissertation Research: Quorum Sensing Influences Soil Nitrogen Mineralization and Plant Nitrogen Availability.

论文研究：群体感应影响土壤氮矿化和植物氮可用性。

基本信息

批准号：
0408194
负责人：
Mary Firestone
金额：
$ 0.95万
依托单位：
University of California-Berkeley
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2004
资助国家：
美国
起止时间：
2004-07-15 至 2006-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0408194&HistoricalAwards=false
关键词：
Dissertation Research Quorum Sensing Influences

项目摘要

ABSTRACTDissertation Research: Quorum sensing influences soil nitrogen mineralization and plant nitrogen availabilityRhizosphere microbial N mineralization provides plants the majority of their N nutrition, but most soil N is organic (chitin, proteins, lignoprotiens and nucleotides). The rate-limiting step in N mineralization may be digestion of these large molecules by microbial extracellular enzymes. Plants exert some control over bacterial function, and new evidence shows that root exudates can disrupt the dominant mechanism of bacterial-bacterial communication (quorum sensing (QS)) and QS-controlled behaviors, such as extracellular enzyme production. Our first hypothesis is that QS affects rhizosphere N mineralization, and plant health, by increasing soil enzyme activity due to increased signal in the rhizosphere. The second hypothesis is that cross-kingdom interactions in the rhizosphere between mycorrhizae, bacteria and plants affect N mineralization via QS. Microcosms allow easy access to the rhizosphere for manipulation of QS through signal addition, measurement of inorganic N pools and N mineralization. A combination of whole-cell biosensors, process rate measurements, decomposing population and community analyses will reveal the degree to which plants control rhizosphere N mineralization and how important this mode of control is for plant N accumulation. To establish this would be to rewrite the current paradigm that plants and microbes are the passive recipients of each other's excess, and set a new precedent for inter-species chemical communication and competition.

摘要散热研究：法定人数感应影响土壤氮矿化和植物氮的可用性，微生物N矿化为植物提供了植物的大部分营养，但大多数土壤是有机的（几丁质，蛋白质，蛋白质，木质孕妇和核苷酸）。 N矿化的速率限制步骤可能是微生物细胞外酶消化这些大分子。植物对细菌功能发挥了一定的控制，新的证据表明，根渗出物可以破坏细菌 - 细菌通信（Quorum Sensing（QS））和QS控制的行为，例如细胞外酶的产生。我们的第一个假设是，QS通过增加根际信号增加的土壤酶活性来影响根际矿化和植物健康。第二个假设是，菌根，细菌和植物之间根际的跨王国相互作用会通过QS影响N矿化。缩影可轻松进入根际，通过添加信号，无机N池的测量和N矿化来操纵QS。整个细胞生物传感器，过程率测量，分解人群和社区分析的结合将揭示植物控制根茎N矿化的程度，以及这种控制方式对植物N积累的重要性。为此，将重写植物和微生物是彼此过剩的被动接受者的当前范式，并为种间化学交流和竞争树立了新的先例。