Dissertation Enhancement: Regulation of N2 Fixation in Trichodesmium

9602462卡彭这个奖项为道格拉斯·卡彭在东海大学海洋科学技术学院举办的为期3个月的国家科学基金会论文增强奖提供支持。卡彭博士的学生玛格丽特·穆赫兰女士将与海洋科学与技术学院教授大木香织博士合作开展一项研究项目，题为《毛霉菌中氮气固定的调节》。毛霉(Trichodesum spp.)是固定氮气的海洋蓝藻，出现在热带和亚热带海洋中，否则以缺乏植物生命而闻名。对于许多陆地系统来说，海洋植物产量的限制主要归因于可利用氮化合物的短缺。Trichodesum spp.利用氮气，氮气是氮的最丰富形式，从而缓解了氮素限制，并为这些系统提供了新的氮素输入。毛霉(Trichodesum spp.)在自然界中可以维持较高的氮气固定率；然而，对这些物种支持氮气固定的生化和生理条件知之甚少，因为它们很难在受控培养系统中维持。Ohki教授和她的合作者已经成功地尝试在培养中种植毛霉菌，但将这种培养物转移到其他实验室被证明是不成功的。本项目将研究在有和没有固定氮化合物的受控条件下生长的NIBB1067毛霉对氮代谢和氮气固定的细胞调节。这些研究的结果将与田间的结果进行比较，以便更好地了解毛霉菌的自然种群。***

9602462 Capone This award provides support for a 3 month National Science Foundation Dissertation Enhancement Award for Douglas Capone at Tokai University, School of Marine Science and Technology. Dr. Capone's student, Ms. Margaret Mulholland will work with Dr. Kaori Ohki, Professor in the School of Marine Science and Technology, on a research project entitled, "Regulation of N2 fixation in Trichodesmium". Trichodesmium spp. are N2 fixing, marine cyanobacteria that occur throughout the tropical and subtropical oceans in areas otherwise noted for their paucity of plant life. As for many terrestrial systems, limitation of oceanic plant production is attributed primarily to a shortage of utilizable nitrogen compounds. Trichodesmium spp., utilize dinitrogen gas, the most abundant form of nitrogen, thereby alleviating nitrogen limitation and providing new nitrogen input into these systems. Trichodesmium spp. can sustain high rates of N2 fixation in nature; however, little is known about the biochemical and physiological conditions that support N2 fixation in these species since they have been difficult to maintain in controlled culture systems. Professor Ohki and her collaborators have been successful in their attempts to grow Trichodesmium in cultures,but transfer of this culture to other laboratories has proven unsuccessful. This project will examine the cellular regulation of N metabolism and N2 fixation in Trichodesmium NIBB1067 grown under controlled conditions with and without fixed nitrogen compounds. Results from these studies will be compared with results from the field in order to better understand the natural populations of Trichodesmium. ***