Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598, USA.
J Microbiol. 2013 Apr;51(2):147-53. doi: 10.1007/s12275-013-2671-2. Epub 2013 Apr 27.
The deeply branching clade of abundant, globally distributed aquatic α-Proteobacteria known as "SAR11", are adapted to nutrient-poor environments such as the surface waters of the open ocean. Unknown prior to 1990, uncultured until 2002, members of the SAR11 clade can now be cultured in artificial, defined media to densities three orders of magnitude higher than in unamended natural media. Cultivation in natural and defined media has confirmed genomic and metagenomic predictions such as an inability to reduce sulfate to sulfide, a requirement for pyruvate, an ability to oxidize a wide variety of methylated and one-carbon compounds for energy, and an unusual form of conditional glycine auxotrophy. Here we describe the metabolism of the SAR11 type strain Candidatus "Pelagibacter ubique" str. HTCC1062, as revealed by genome-assisted studies of laboratory cultures. We also describe the discovery of SAR11 and field studies that have been done on natural populations.
深分支的丰富的、全球分布的水生α-变形菌称为“SAR11”，适应于贫营养环境，如开阔海洋的表面水域。在 1990 年之前是未知的，直到 2002 年才被培养，SAR11 分支的成员现在可以在人工、定义的培养基中培养，密度比未改良的天然培养基高三个数量级。在天然和定义的培养基中的培养证实了基因组和宏基因组的预测，例如无法将硫酸盐还原为硫化物，需要丙酮酸，能够氧化各种甲基化和一碳化合物以获取能量，以及一种不寻常的条件性甘氨酸营养缺陷型。在这里，我们通过对实验室培养物的基因组辅助研究描述了 SAR11 模式菌株候选“Pelagibacter ubique”str. HTCC1062 的代谢情况。我们还描述了 SAR11 的发现和对自然种群进行的实地研究。
