Laboratoire de Microbiologie des Environnements Extrêmes, UMR 6197, IFREMER Centre de Brest, Département Etudes des Environnements Profonds, Université de Bretagne Occidentale, Plouzané, France.
Antonie Van Leeuwenhoek. 2011 Nov;100(4):639-53. doi: 10.1007/s10482-011-9620-z. Epub 2011 Jul 13.
Pockmarks are seabed geological structures sustaining methane seepage in cold seeps. Based on RNA-derived sequences the active fraction of the archaeal community was analysed in sediments associated with the G11 pockmark, in the Nyegga region of the Norwegian Sea. The anaerobic methanotrophic Archaea (ANME) and sulfate-reducing bacteria (SRB) communities were studied as well. The vertical distribution of the archaeal community assessed by PCR-DGGE highlighted the presence of ANME-2 in surface sediments, and ANME-1 in deeper sediments. Enrichments of methanogens showed the presence of hydrogenotrophic methanogens of the Methanogenium genus in surface sediment layers as well. The active fraction of the archaeal community was uniquely composed of ANME-2 in the shallow sulfate-rich sediments. Functional methyl coenzyme M reductase gene libraries showed that sequences affiliated with the ANME-1 and ANME-3 groups appeared in the deeper sediments but ANME-2 dominated both surface and deeper layers. Finally, dissimilatory sulfite reductase gene libraries revealed a high SRB diversity (i.e. Desulfobacteraceae, Desulfobulbaceae, Syntrophobacteraceae and Firmicutes) in the shallow sulfate-rich sediments. The SRB diversity was much lower in the deeper section. Overall, these results show that the microbial community in sediments associated with a pockmark harbour classical cold seep ANME and SRB communities.
麻坑是海底地质结构，支持冷渗流中的甲烷渗漏。基于 RNA 衍生序列，对与挪威海尼格加地区的 G11 麻坑相关沉积物中的古菌群落的活性部分进行了分析。还研究了厌氧甲烷氧化古菌 (ANME) 和硫酸盐还原菌 (SRB) 群落。通过 PCR-DGGE 评估的古菌群落的垂直分布突出了表面沉积物中存在 ANME-2，以及深部沉积物中存在 ANME-1。产甲烷菌的富集表明，在表层沉积物中存在产甲烷菌属的氢营养型产甲烷菌。古菌群落的活性部分在浅层富硫酸盐沉积物中仅由 ANME-2 组成。功能甲基辅酶 M 还原酶基因文库表明，与 ANME-1 和 ANME-3 组相关的序列出现在更深的沉积物中，但 ANME-2 主导着表层和深层。最后，异化亚硫酸盐还原酶基因文库揭示了浅层富硫酸盐沉积物中 SRB 的多样性（即脱硫杆菌科、脱硫球菌科、产甲烷杆菌科和厚壁菌门）很高。在更深的部分，SRB 的多样性要低得多。总的来说，这些结果表明与麻坑相关的沉积物中的微生物群落包含典型的冷渗流 ANME 和 SRB 群落。
