Bacteria Genomes - FRANKIA sp.

Frankia sp. is a soil actinomycete with a typical hyphal morphology that forms symbiotic associations with a number of diverse non-leguminous plants.

Organisms in symbiotic relationships with plant hosts are necessary for the health and survival of certain plants. They assist in creating and transporting certain root hormones, controlling pathogens and nematodes, root exploration, water retention, mineral uptake, and resource sharing. Frankia specifically fixes nitrogen in the air and converts atmospheric N2 gas into ammonia.

Frankia fix nitrogen while living in root nodules on actinorhizal plants. Frankia can supply most or all of the host plants' nitrogen needs, consequently, actinorhizal plants colonize and often thrive in soils that are low in combined nitrogen.

Frankia has symbiotic relationships with numerous dicot plants and is said to be responsible for 15% of the biologically fixed nitrogen in the world. One type of symbiotic relationship including plant, mycorrhiza, and Frankia is called a tripartite relationship and is a complex, multi-layered community of organisms that protect and support each other.

This symbiosis has become increasingly important as climate changes threaten to remake the global landscape over the next several decades.

The recent availability of the Frankia genome may help clarify the evolution of prokaryote/plant symbioses, environmental and geographical adaptation, metabolic diversity and horizontal gene flow among symbiotic prokaryotes.

References:

http://www.laspilitas.com/advanced/advroots.htm
http://genome.jgi-psf.org/draft_microbes/fra_c/fra_c.home.html
http://biology.kenyon.edu/Microbial_Biorealm/bacteria/gram-positive/frankia/Frankia.htm
http://web.uconn.edu/mcbstaff/benson/Frankia/FrankiaHome.htm
http://www.laspilitas.com/classes/Frankia.html