The fate of lysis products of picocyanobacteria contributes to marine humic-like chromophoric dissolved organic matter

微微蓝细菌裂解产物的命运有助于海洋腐殖质类发色溶解有机物

• 批准号: 1829888
• 负责人: Michael Gonsior
• 金额: $ 61.28万
• 依托单位: University of Maryland Center for Environmental Sciences
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-02-01 至 2023-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1829888&HistoricalAwards=false
• 关键词: fate; lysis; products; picocyanobacteria; contributes

AbstractThis study focuses on the sources and composition of colored dissolved organic matter (CDOM) in the ocean. CDOM is a part of water that absorbs sunlight. This material is important because it filters out harmful ultraviolet radiation. Scientists use it to track the movement of carbon and other important biological and chemical processes in the ocean. Organisms such as algae living in the open ocean have been shown to be sources of CDOM, but the chemical composition of these algal natural products remains to be discovered. Recent results from studying common algae show that viruses may break down algal cells and release material that looks like CDOM. This study will use new tools to find out if viruses and algae are creating this material and study its chemical makeup. This project will support two graduate students and provide summer internships for undergraduates through the NSF Research Experiences for Undergraduates (REU) program. The investigators will participate in a range of education and outreach activities.The sources and structural nature of marine CDOM within the oceans remain unclear and continue to be a subject of debate. Marine in situ sources of CDOM have been suggested and some have been confirmed, but thus far none could explain the ubiquitous appearance of the so called "humic-like" CDOM component. Unique features of this component include its unusual exponential behavior in ultraviolet-visible (UV-Vis) absorbance with the absorbance extending well above 400 nm, and the large Stoke's shift in fluorescence spectroscopy. Picocyanobacteria are ubiquitous in the World's Oceans and make up 50 % of the autotrophic marine primary production. Preliminary results showed that the picocyanobacteria Synechococcus and Prochlorococcus release CDOM that matched the "humic-like" appearance of globally observed marine CDOM after virus-induced lysis. The main focus of this study is the characterization of the optical properties and molecular composition of viral-lysed DOM (VDOM) from different strains of Synechococcus and Prochlorococcus and additionally Trichodesmium which was shown in a previous study to also release CDOM. Associations between the chemical characterization information and metagenomics and transcriptomics data will be investigated for picocyanobacteria in the Pacific and Atlantic Oceans. This study includes long-term incubation experiments to determine the persistence of picocyanobacteria-derived CDOM as well as changes in microbial communities and processes (gene expression) that are related to the degradation of VDOM during the incubation period.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

摘要本文对海洋中彩色溶解有机物（CDOM）的来源和组成进行了研究。CDOM是水吸收阳光的一部分。这种材料很重要，因为它能过滤掉有害的紫外线辐射。科学家们用它来追踪海洋中碳的运动和其他重要的生物和化学过程。生活在开阔海洋中的藻类等生物已被证明是CDOM的来源，但这些藻类天然产物的化学成分仍有待发现。最近对普通藻类的研究结果表明，病毒可能会破坏藻类细胞，释放出类似CDOM的物质。这项研究将使用新工具来发现病毒和藻类是否在制造这种物质，并研究其化学组成。该项目将资助两名研究生，并通过美国国家科学基金会本科生研究经验项目（REU）为本科生提供暑期实习机会。调查人员将参加一系列教育和推广活动。海洋中海洋CDOM的来源和结构性质仍然不清楚，并继续成为争论的主题。海洋中的CDOM就地来源已被提出，有些已被证实，但到目前为止，没有人能够解释所谓的“腐殖质样”CDOM成分的普遍存在。该成分的独特特征包括其不寻常的指数行为在紫外可见（UV-Vis）吸光度延伸远高于400nm，以及荧光光谱的大斯托克位移。碧青杆菌在世界海洋中普遍存在，占自养海洋初级生产的50%。初步结果表明，piccyanobacteria Synechococcus和Prochlorococcus释放的CDOM与全球观测到的海洋CDOM在病毒诱导裂解后的“腐殖质样”外观相匹配。本研究的主要重点是表征不同菌株的病毒裂解DOM （VDOM）的光学性质和分子组成，这些菌株来自聚藻球菌和原绿球藻，另外还有在先前的研究中显示也释放CDOM的Trichodesmium。将研究太平洋和大西洋picocyanobacteria的化学特征信息与宏基因组学和转录组学数据之间的关系。本研究包括长期孵育实验，以确定picocyanobacterie -derived CDOM的持久性，以及在孵育期间与VDOM降解相关的微生物群落和过程（基因表达）的变化。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Presence of toxin-antitoxin systems in picocyanobacteria and their ecological implications

• DOI: 10.1038/s41396-020-00746-4
• 发表时间: 2020-08-19
• 期刊: ISME JOURNAL
• 影响因子: 11
• 作者: Fucich, Daniel;Chen, Feng
• 通讯作者: Chen, Feng

Correspondence between DOM molecules and microbial community in a subtropical coastal estuary on a spatiotemporal scale

亚热带沿岸河口DOM分子与微生物群落的时空对应关系

• DOI: 10.1016/j.envint.2021.106558
• 发表时间: 2021-04-23
• 期刊: ENVIRONMENT INTERNATIONAL
• 影响因子: 11.8
• 作者: Chen, Qi;Chen, Feng;Zheng, Qiang
• 通讯作者: Zheng, Qiang

Microbial transformation of virus-induced dissolved organic matter from picocyanobacteria: coupling of bacterial diversity and DOM chemodiversity

• DOI: 10.1038/s41396-019-0449-1
• 发表时间: 2019-10-01
• 期刊: ISME JOURNAL
• 影响因子: 11
• 作者: Zhao, Zhao;Gonsior, Michael;Chen, Feng
• 通讯作者: Chen, Feng