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

在这个项目中，Prochloron didemni的基因组将被测序，注释和用于比较基因组研究，Prochloron didemni是一种光合细菌，与珊瑚礁中发现的原始动物共生。这种共生关系是重要的，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与其他脊索动物（如人类）之间的共生关系;（2）共生体是蓝藻原绿藻，因此是植物光合细胞器的近亲（叶绿体）;和（3）目前没有从蓝细菌共生体中获得的基因组。基因组的分析将被用来阐明负责脊索动物和细菌之间的共生基因，以进一步确定独特的光合特性的prochlorophytes和确定哪些因素是重要的自由生活的蓝藻转化成专性共生体。此外，该项目应有助于理解更广泛的共生背景，如互惠和致病协会之间的区别，微生物共生体在海洋无脊椎动物生态学中的深刻作用，以及通过共生创新的机制，生命历史上的一个主要过程。该项目将是基因组研究所（TIGR）、犹他州大学和加州圣地亚哥大学之间的合作努力，将涉及来自这些研究所和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，光合作用是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，特别是在与植物和藻类叶绿体有关的生物体中，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。

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.