Spaans Sebastiaan K, van der Oost John, Kengen Servé W M
Laboratory of Microbiology, Wageningen University, PO Box 8033, 6700 EJ, Wageningen, The Netherlands,
Extremophiles. 2015 Jul;19(4):741-50. doi: 10.1007/s00792-015-0750-5. Epub 2015 May 8.
The euryarchaeon Thermococcus kodakarensis is a well-characterized anaerobic hyperthermophilic heterotroph and due to the availability of genetic engineering systems it has become one of the model organisms for studying Archaea. Despite this prominent role among the Euryarchaeota, no data about the ploidy level of this species is available. While polyploidy has been shown to exist in various Euryarchaeota, especially Halobacteria, the chromosome copy number of species belonging to one of the major orders within that phylum, i.e., the Thermococcales (including Thermococcus spp. and Pyrococcus spp.), has never been determined. This prompted us to investigate the chromosome copy number of T. kodakarensis. In this study, we demonstrate that T. kodakarensis is polyploid with a chromosome copy number that varies between 7 and 19 copies, depending on the growth phase. An apparent correlation between the presence of histones and polyploidy in Archaea is observed.
嗜热栖热菌是一种特征明确的厌氧超嗜热异养生物，由于其基因工程系统的可用性，它已成为研究古菌的模式生物之一。尽管在广古菌门中具有这一突出地位，但关于该物种倍性水平的数据却尚无可用。虽然已证明多倍体存在于各种广古菌中，尤其是嗜盐菌，但属于该门中一个主要目（即热球菌目，包括嗜热栖热菌属和火球菌属）的物种的染色体拷贝数从未得到确定。这促使我们去研究嗜热栖热菌的染色体拷贝数。在本研究中，我们证明嗜热栖热菌是多倍体，其染色体拷贝数在7至19个拷贝之间变化，具体取决于生长阶段。我们观察到古菌中组蛋白的存在与多倍体之间存在明显的相关性。
