Hyperthermophiles in the History of Life

报告人：Professor Karl O. Stetter

报告人单位： Lehrstuhl für Mikrobiologie, Universit？t Regensburg, Germany

报告题目：Hyperthermophiles in the History of Life

时间及地点：2015年12月7日（周一）上午10:00 ，A203会议室

主持人：黄力 研究员

报告人简介：

    Karl O. Stetter教授是德国科学院院士，嗜热古菌研究的先驱。他出生于德国慕尼黑，毕业于慕尼黑工业大学(Technische Universitat Munich)，1980-2002年任德国雷根斯堡大学(University of Regensburg)微生物学教授和微生物系主任，并在那里建立了古菌研究中心(Archaea Center)。1989年以来，他还担任了美国加州大学洛杉矶分校微生物学和分子遗传学系的特聘教授(Professor Above-Scale)。1994年，与他人共同创建DIVERSA公司(a San Diego- based Biotec Company, now part of BASF Enzymes, North America)。

    Stetter教授发现和分离了超过1500株极端嗜热古菌和细菌，包括50多个新种、18个新属，以及10个新目。这些微生物包括113^oC超嗜热菌、纳米古菌以及PCR常用的高保真DNA聚合酶Pfu DNA polymerase产生菌强烈火球菌(Pyrococcus furiosus)。发表相关研究论文348篇。为了表彰他的杰出成就，荷兰皇家艺术与科学院于2003年授予Stetter教授列文虎克勋章。该勋章每10年颁发一次，用于奖励在微生物学领域作出最杰出贡献的科学家。

报告内容摘要：

To-day, hyperthermophilic (“super-heat-loving”) bacteria and archaea are found within high temperature environments, representing the upper temperature border of life. They grow optimally at above 80°C and exhibit an upper temperature border of growth of up to 113°C. Members of the genera Pyrodictium and Pyrolobus even survive at least one hour of autoclaving. In their basically anaerobic environments, hyperthermophiles gain energy mainly by inorganic redox reactions employing compounds like molecular hydrogen, carbon dioxide, sulphur, nitrate and ferric and ferrous iron. In addition, several are opportunistic or obligate heterotrophs. Based on their growth requirements, hyperthermophiles could have existed already on the Early Earth, about 3.9 billion years ago. In agreement, within the ss rRNA-based phylogenetic tree of life they occupy all the short deep-branching lineages closest to the root. The deepest- branching archaeal lineages are represented by the Nanoarchaeota and the Korarchaeota. Various members of both groups are world-wide distributed and so far hardly investigated. Cells of Nanoarchaeum equitans consist of minicocci, only 0.4 μm in diameter. Their cultivation requires specific cell-cell-contact with Ignicoccus hospitalis, a crenarchaeal host. The N. equitans genome is among the smallest known to date (490,885 bp). From the first member of the Korarchaeota, an enrichment culture and a complete genome sequence has been obtained recently. It revealed an unprecedented heterogeneous gene complement suggesting that the Korarchaeota had diverged very early in the history of the archaeal lineage.