The discovery, published in The ISME Journal, used computational methods to search through vast amounts of sequenced environmental DNA for the genes that make vitamin B12, identifying the likely producers in marine and freshwater environments.
The analysis discovered that the microbial family Thaumarchaeota are likely dominant vitamin B12 producers. This group from the Archea domain has never before been associated with vitamin B12 synthesis, explained the team behind the work.
Led by Professors Andew Doxey and Josh Neufeld, from the University of Waterloo, the team noted that although vitamin B12 is an essential molecule required by most life on the planet, it is only produced by a relatively small group of microorganisms because it is so large and complex. For humans, vitamin B12 plays a key role in maintaining the brain and nervous systems, as well as DNA synthesis in cells throughout the body.
"We assumed that most major global sources of something as fundamental as vitamin B12 would have already been characterized, and so this finding changes how we think about global production of this important vitamin," said Doxey.
"Because Thaumarchaeota are among the most abundant organisms on the planet, especially in marine environments, their contribution to vitamin B12 production have enormous implications for ecology and metabolism in the oceans," said added Neufeld – adding that the availability of vitamin B12 may control how much or how little biological productivity by phytoplankton takes place in the oceans.
The work may identification of a new source of naturally produced vitamin B12 may also have implications for the sourcing of the essential nutrient for industry players.
Source: The ISME Journal
Published online ahead of print, doi: 10.1038/ismej.2014.142
"Aquatic metagenomes implicate Thaumarchaeota in global cobalamin production"
Authors: Andrew C Doxey, Daniel A Kurtz, Michael DJ Lynch, Laura A Sauder, Josh D Neufeld