Hydrothermal vents: Hot spots of microbial...( MBL WOODS HOLE MAThousands of new ki...)

MBL, WOODS HOLE, MAThousands of new kinds of marine microbes have been discovered at two deep-sea hydrothermal vents off the Oregon coast by scientists at the MBL (Marine Biological Laboratory) and University of Washingtons Joint Institute for the Study of Atmosphere and Ocean. Their findings, published in the October 5 issue of the journal Science, are the result of the most comprehensive, comparative study to date of deep-sea microbial communities that are responsible for cycling carbon, nitrogen, and sulfur to help keep Earth habitable.

Using a new analytical technique called 454 tag sequencing, the scientists surveyed one million DNA sequences of bacteria and archaea, two of the three major domains of life. The DNA was taken from samples collected from two hydrothermal vents on the Pacific deep-sea volcano, Axial Seamount.

The researchers discovered that while there may be as few as 3,000 different kinds of archaea at these sites, the bacteria exceed 37,000 different kinds.

Most of these bacteria had never been reported before, and hundreds were so different from known microbes that we could only identify them to the level of phylum, says lead author, Julie Huber of the MBL. Clearly, additional sampling of these communities will be necessary to determine the true diversity.

The research also revealed that the microbial population structures differed between vent sites due to their different geochemical environments. The ability to link environmental characteristics with microbial population structures using 454 tag sequencing allows scientists to assess how natural and manmade environmental changes are affecting diverse habitats on Earth.

Until now, microbiologists have had limited tools for assessing microbial populations and diversity. The MBLs 454 tag sequencing strategy is an important contribution to the young science of metagenomics, which seeks to characterize communities of organisms through genomic ana
'/>"/>