专家简介：
董宏坡，华东师范大学河口海岸学国家重点实验室研究员，博士生导师。安徽师范大学生物学学士，厦门大学生物学硕士，厦门大学和美国马里兰大学环境科学联合培养博士，美国马里兰大学博士后，曾任暨南大学水环境科学研究中心副教授。长期从事海洋微生物驱动的碳氮循环和微生物生理代谢功能研究；利用环境组学结合同位素技术，系统研究了光合微生物吸收活性氮素的分子机制；利用氨氧化微生物纯菌结合现场观测，深入探讨了滨海湿地硝化微生物驱动的氧化亚氮产生过程；基于宏基因组学技术结合现场观测，首次在滨海湿地发现了2个新型古菌类群，一个参与了湿地主要污染物芳香烃的降解，另一个参与了湿地甲烷的代谢。
最近在海洋阿斯加德古菌多样性及其与地球演化和真核生命起源研究方面获得重要突破。利用计算生物学研究技术，首次揭示真核生物和古菌共同祖先的起源时间线以及可能的古菌姐妹枝，并破译了该共同祖先可能的生活方式，该研究结果对于理解地球上生命的起源奥秘及演化历程有重要意义。相关研究以Research Article 的形式在Nature上发表。
目前以第一或通讯作者发表SCI论文30篇，其中多篇文章发表在国际权威期刊上，包括Nature, ISME J (2篇)，Environmental Science and Technology，Water Research, Geochimica et Cosmochimica Acta, Plant Physiology, Limnology and Oceanography (2篇)。入选广东省扬帆支持计划。曾获得中国海洋湖沼学会优秀论文二等奖。现任上海市微生物学会海洋专委会委员、教育部学位中心特邀专家、国家自然科学基金委重点项目评审专家。
报告摘要：
Research on the morphology, physiology and genomics of Asgard archaea has provided valuable insights into the evolutionary history of eukaryotes. A previous study suggested that eukaryotes are nested within Heimdallarchaeia, but their exact phylogenetic placement within Asgard archaea remains controversial. This debate complicates understanding of the metabolic features and timescales of early eukaryotic ancestors. Here we generate 223 metagenome-assembled nearly complete genomes of Asgard archaea that have not previously been documented. We identify 16 novel lineages at the genus level or higher, which substantially expands the known phylogenetic diversity of Asgard archaea. Through sophisticated phylogenomic analysis of this expanded genomic dataset involving multiple marker sets we infer that eukaryotes evolved before the diversification of all sampled Heimdallarchaeia, rather than branching with Hodarchaeales within the Heimdallarchaeia. This difference in the placement of eukaryotes is likely caused by the previously underappreciated chimeric nature of Njordarchaeales genomes, which we find are composed of sequences of both Asgard and TACK archaea (Asgard’s sister phylum). Using ancestral reconstruction and molecular dating, we infer that the last Asgard archaea and eukaryote common ancestor emerged before the Great Oxidation Event and was probably an anaerobic H2-dependent acetogen. Our findings support the hydrogen hypothesis of eukaryogenesis, which posits that eukaryotes arose from the fusion of a H2-consuming archaeal host and a H2-producing protomitochondrion.
