US EPA

2034396 

Journal Article 

Filamentous sulfur bacteria, Beggiatoa spp., in arctic marine sediments (Svalbard, 79 degrees N) 

Jorgensen, BoB; Dunker, R; Gruenke, S; Roy, H 

2010 

Yes 

FEMS Microbiology Ecology
ISSN: 0168-6496
EISSN: 1574-6941 

73 

3 

500-513 

English 

20608982 

10.1111/j.1574-6941.2010.00918.x 

WOS:000280633000008 

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. 

Beggiatoa; sulfur bacteria; benthic community; microbial mat; marine sediment; Arctic Ocean