Microbial Genome Sequencing: Genome Sequence of Prochloron didemni: An Obligate Cyanobacterial Symbiont

微生物基因组测序：原绿藻基因组序列：专性蓝藻共生体

• 批准号: 0842636
• 负责人: Jacques Ravel
• 金额: --
• 依托单位: University of Maryland at Baltimore
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0842636&HistoricalAwards=false
• 关键词: Microbial; Genome; Sequencing; Sequence; Prochloron

In this project, the genome of Prochloron didemni, a photosynthetic bacteria that lives in a symbiosis with a primitive animal found in coral reefs, will be sequenced, annotated and used for comparative genomic studies. This symbiosis is important for many reasons including (1) that the host (the coral reef ascidian Lissoclinum patella) is a primitive representative of the chordate animals - thus this study may help understand symbioses between bacteria and other chordates such as humans; (2) that the symbiont is a cyanobacterial prochlorophyte and thus is a close relative of the photosynthetic organelles of plants (chloroplasts); and (3) there are no genomes currently available from cyanobacteria symbionts. Analysis of the genome will be used to elucidate genes responsible for symbioses between chordates and bacteria, to further define the unique photosynthetic characteristics of prochlorophytes and to determine which factors are important in the conversion of free-living cyanobacteria into obligate symbionts. In addition, this project should help in understanding the broader context of symbiosis such as the distinction between mutualistic and pathogenic associations, the profound role of microbial symbionts in marine invertebrate ecology, and the mechanisms of innovation through symbiosis, a major process in the history of life. This project will be a collaborative effort between The Institute for Genomic Research (TIGR), the University of Utah and the University of California San Diego and will involve graduate and undergraduate students from these institutes and from the Republic of Palau where the symbiosis occurs. Perhaps most importantly, photosynthesis represents the primary pathway for fixation of carbon from the atmosphere. Thus a better understanding of the diversity of carbon fixation pathways, especially in the organisms related to plant and algal chloroplasts, will potentially help in efforts to understand global carbon cycles and eventually to mitigate the effects of carbon being released into the atmosphere by human activity.

在该项目中，Prochromon didemni（一种与珊瑚礁中发现的原始动物共生的光合细菌）的基因组将被测序、注释并用于比较基因组研究。这种共生关系很重要，原因有很多，包括（1）宿主（珊瑚礁海鞘 Lissoclinum patella）是脊索动物的原始代表 - 因此这项研究可能有助于了解细菌和其他脊索动物（例如人类）之间的共生关系； （2）共生体是蓝藻原叶绿藻，因此是植物光合细胞器（叶绿体）的近亲； (3) 目前还没有蓝藻共生体的基因组。基因组分析将用于阐明负责脊索动物和细菌之间共生的基因，进一步定义原叶绿植物独特的光合作用特征，并确定哪些因素在自由生活的蓝细菌转化为专性共生体中起重要作用。此外，该项目应有助于理解更广泛的共生背景，例如互利关联和致病关联之间的区别、微生物共生体在海洋无脊椎动物生态学中的深刻作用，以及通过共生进行创新的机制，这是生命史上的一个重要过程。该项目将是基因组研究所 (TIGR)、犹他大学和加州大学圣地亚哥分校之间的合作项目，并将涉及来自这些机构以及来自共生发生地帕劳共和国的研究生和本科生。也许最重要的是，光合作用代表了固定大气中碳的主要途径。因此，更好地了解碳固定途径的多样性，特别是与植物和藻类叶绿体相关的生物体，将可能有助于了解全球碳循环，并最终减轻人类活动释放到大气中的碳的影响。