International Census of Marine Microbes reveals a greater level of marine diversity using ultrafast sequencing system from Roche Diagnostics
Roche Applied Science and 454 Life Sciences report that the International Census of Marine Microbes has purchased a Genome Sequencer 20 system as part of a multi-institutional study of microbial life in the world's oceans.
The announcement follows a publication in the Proceedings of the National Academy of Sciences online journal describing how the Genome Sequencer 20 and 454 Sequencing revealed that microbial diversity is ten to 100 times greater than scientists knew existed in the ocean.
''We can use the Genome Sequencer 20 to inventory and provide exquisite detail of the bacteria in any sample, allowing us to pick up subtle changes,'' said Mitchell Sogin, director of Marine Biological Laboratory's Josephine Bay Paul Center for Comparative and Molecular Biology and Evolution.
''454 Sequencing enables a level of ultra-deep sequencing that reveals ten to 100 times more diversity than we previously realized using Sanger sequencing".
Sogin and other scientists now believe the number of microorganisms in the ocean could be in the range of 5 million to 10 million, well beyond the 500,000 that studies had previously revealed.
These microorganisms could hold the answers to how life evolved in the ocean and what impact environmental changes have on marine ecosystems.
"The Genome Sequencer 20 system has another application in a new field, allowing us to see marine microbial diversity to which we were blind before," stated Manfred Baier, head of Roche Applied Science.
''The palette of microbes could provide a picture of the health of our oceans".
The Genome Sequencer 20 System is the first sequencing system in the market that can generate hundreds of thousands of DNA sequences in one run, rapidly and comprehensively conducting high-throughput nucleotide sequencing.
454 Sequencing, which is more comprehensive and cost-efficient than conventional methods, enabled Sogin's team to sequence DNA samples from the harshest ocean environments in the world, such as those marked by extreme hot temperatures or high acidity.
Scientists used a method of 454 Sequencing called '454 tag sequencing' on eight water samples taken from deep in the Pacific and Atlantic oceans, including water near hydrothermal vents on an underwater Pacific Ocean volcano 300 miles off the coast of Oregon, and from Atlantic Ocean sites between Greenland and Ireland.
The Genome Sequencer 20 system requires only small snippets of genetic code to identify an organism, which makes it possible to perform thousands of such tests simultaneously.
Each sample showed a diverse group of microorganisms.
In a single litre of seawater, for example, researchers found more than 20,000 microorganisms, many of them rare or in low abundance.
"Dr Sogin is demonstrating the diversity of applications enabled by 454 Sequencing," explained Christopher McLeod, president and CEO of 454 Life Sciences.
"Ultra-deep sequencing of marine microbes reveals an unprecedented level of detail compared to conventional sequencing technologies".
With Genome Sequencer 20 system, scientists will be able to study patterns and trends of these rare microorganisms to determine the long-term effects of environmental changes in the ocean.
For example, such knowledge could have been useful in evaluating the potential environmental damage to the Gulf Coast inflicted by Hurricane Katrina.
