Max Planck Institute for Marine Microbiology, Bremen, Germany.
FEMS Microbiol Ecol. 2010 Sep;73(3):500-13. doi: 10.1111/j.1574-6941.2010.00918.x. Epub 2010 May 29.
Fjord sediments on the west coast of the arctic archipelago Svalbard were surveyed to understand whether large filamentous sulfur bacteria of the genus Beggiatoa thrive at seawater temperatures permanently near freezing. Two sediments had abundant populations of Beggiatoa, while at six sites, only sporadic occurrences were observed. We conclude that Beggiatoa, although previously unnoticed, are widespread in these arctic fjord sediments. Beggiatoa ranged in diameter from 2 to 52 microm and, by those tested, stored nitrate in vacuoles at up to 260 mM. The 16S rRNA gene sequence of a 20-microm-wide filament is closely associated with other large, marine, nitrate-storing Beggiatoa. The Beggiatoa mostly occurred in the upper 2-5 cm of oxidized surface sediment between oxygen and the deeper sulfidic zone. In spite of a very low or an undetectable sulfide concentration, sulfate reduction provided abundant H(2)S in this zone. The total living biomass of Beggiatoa filaments at one study site varied over 3 years between 1.13 and 3.36 g m(-2). Because of their large size, Beggiatoa accounted for up to 15% of the total prokaryotic biomass, even though the filament counts at this site were rather low, comprising <1/10,000 of the bacterial numbers on a cell basis.
对斯瓦尔巴群岛北极峡湾西海岸的沉积物进行了调查，以了解在海水温度接近冰点的情况下，巨型丝状硫细菌Beggiatoa 是否大量存在。有两个沉积物中有大量的 Beggiatoa 存在，而在六个地点只观察到零星的出现。我们的结论是，尽管以前未被注意到，但 Beggiatoa 在这些北极峡湾沉积物中广泛存在。Beggiatoa 的直径从 2 到 52 微米不等，通过测试，其在液泡中储存的硝酸盐浓度高达 260 毫摩尔。20 微米宽的丝状菌的 16S rRNA 基因序列与其他大型海洋硝酸盐储存 Beggiatoa 密切相关。Beggiatoa 主要存在于氧化表面沉积物的上层 2-5 厘米处，介于氧气和更深的硫化物区之间。尽管硫化物浓度非常低或无法检测到，但硫酸盐还原在该区域提供了丰富的 H(2)S。在一个研究地点，Beggiatoa 丝状菌的总活生物量在 3 年内变化范围在 1.13 到 3.36 克/平方米之间。由于它们的体积较大，即使在这个地点的丝状菌计数相对较低，仅占细菌数量的万分之一，Beggiatoa 也占总原核生物量的 15% 左右。
