Marine Biotechnology Fellowship: Development of Molecular Tools for the Investigation of Urea Utilization by Marine Cyanobacteria in the Field

小行星9321535 氮素营养的差异可能会影响植物的分布，因为每种氮源具有不同的有效性模式。铵，这是大多数浮游植物的首选氮源，往往没有足够的数量来支持浮游植物的生长。因此，尿素和硝酸盐是浮游植物重要的氮源。 由于尿素（如铵）是在浮游生物中产生的，而硝酸盐是从深水中提供的，因此各种氮源的相对可用性在空间和时间上都是变化的。 目前培养的海洋蓝细菌能够以铵或硝酸盐作为唯一氮源生长，但只有大约一半的海洋蓝细菌能够利用尿素。这表明尿素可能会影响海洋蓝藻的生长速率和分布。本计画将发展蓝藻尿素酶之分子探针，并将其应用于野外研究，以探讨蓝藻尿素酶利用与海洋基本参数之关系。将使用分子探针，因为任何其他技术都不可能提供理解这些关系所需的灵敏度和分辨率。 ***

9321535 COLLIER Differences in nitrogen nutrition might affect the distribution of phyoplankters because each nitrogen source has different patterns of availability. Ammonium, which is the preferred nitrogen source of most phytoplankton, is often not available in sufficient quantities to support phytoplankton growth. Therefore urea and nitrate are important nitrogen sources for the phytoplankton. Because urea like ammonium is produced within the plankton, while nitrate is supplied from deeper water, the relative availability of the various nitrogen sources changes both in space and in time. Marine cyanobacteria currently in culture are able to grow with ammonium or nitrate as sole nitrogen source, but only about half of them are able to utilize urea. This suggest that urea may affect the growth rate and distribution of marine cyanobacteria. This project, will develop molecular probes to cyanobacterial ureases which will then be used in field studies to examine the relationships between cyanobacterial urease utilization and basic oceanographic parameter. Molecular probes will be used because it is unlikely that any other techniques can provide the sensitivity and resolution required to understand these relationships. ***