van der Maarel M J, Artz R R, Haanstra R, Forney L J
Laboratory of Microbial Ecology, Centre for Ecological and Evolutionary Studies, University of Groningen, NL-9751 NN Haren, The Netherlands.
Appl Environ Microbiol. 1998 Aug;64(8):2894-8. doi: 10.1128/AEM.64.8.2894-2898.1998.
Recent studies have shown that archaea which were always thought to live under strict anoxic or extreme environmental conditions are also present in cold, oxygenated seawater, soils, the digestive tract of a holothurian deep-sea-deposit feeder, and a marine sponge. In this study, we show, by using PCR-mediated screening in other marine eukaryotes, that marine archaea are also present in the digestive tracts of flounder and grey mullet, two fish species common in the North Sea, in fecal samples of flounder, and in suspended particulate matter of the North Sea water column. No marine archaea could be detected in the digestive tracts of mussels or the fecal pellets of a copepod species. The archaeal 16S ribosomal DNA clone libraries of feces of flounder and the contents of the digestive tracts of grey mullet and flounder were dominated by group II marine archaea. The marine archaeal clones derived from flounder and grey mullet digestive tracts and feces formed a distinct cluster within the group II marine archaea, with 76.7 to 89. 8% similarity to previously described group II clones. Fingerprinting of the archaeal community of flounder digestive tract contents and feces by terminal restriction fragment length polymorphism of archaeal 16S rRNA genes after restriction with HhaI showed a dominant fragment at 249 bp, which is likely to be derived from group II marine archaea. Clones of marine archaea that were closely related to the fish-associated marine archaea clones were obtained from suspended particulate matter of the water column at two stations in the North Sea. Terminal restriction fragment length polymorphism fingerprinting of the archaeal community present in suspended particulate matter showed the same fragment pattern as was found for the archaeal community of the flounder digestive tract contents and feces. These data demonstrate that marine archaea are present in the digestive tracts and feces of very common marine fish. It is possible that the marine archaea associated with the digestive tracts of marine fish are liberated into the water column through the feces and subsequently contribute to the marine archaeal community of suspended particulate matter.
最近的研究表明，古菌以往一直被认为生活在严格的缺氧或极端环境条件下，如今在寒冷、含氧的海水、土壤、深海沉积物摄食海参的消化道以及一种海绵中也有发现。在本研究中，我们通过对其他海洋真核生物进行PCR介导的筛选发现，在北海常见的两种鱼类——比目鱼和鲻鱼的消化道、比目鱼的粪便样本以及北海水柱中的悬浮颗粒物中也存在海洋古菌。在贻贝的消化道或一种桡足类动物的粪便颗粒中未检测到海洋古菌。比目鱼粪便以及鲻鱼和比目鱼消化道内容物的古菌16S核糖体DNA克隆文库主要由II型海洋古菌组成。源自比目鱼和鲻鱼消化道及粪便的海洋古菌克隆在II型海洋古菌中形成了一个独特的聚类，与先前描述的II型克隆的相似性为76.7%至89.8%。在用HhaI酶切后，通过古菌16S rRNA基因的末端限制性片段长度多态性对比目鱼消化道内容物和粪便的古菌群落进行指纹分析，结果显示在249 bp处有一个优势片段，该片段可能源自II型海洋古菌。从北海两个站点的水柱悬浮颗粒物中获得了与鱼类相关的海洋古菌克隆密切相关的海洋古菌克隆。对悬浮颗粒物中古菌群落进行的末端限制性片段长度多态性指纹分析显示，其片段模式与比目鱼消化道内容物和粪便的古菌群落相同。这些数据表明，海洋古菌存在于非常常见的海洋鱼类的消化道和粪便中。与海洋鱼类消化道相关的海洋古菌有可能通过粪便释放到水柱中，随后对悬浮颗粒物的海洋古菌群落有所贡献。
