Oral Technical Session: Fungal Genomics and Ecology

82-O

Co-evolution of Mortierella elongata and its endosymbiotic bacterium.
G. BONITO (1), A. Gryganskyi (1), K. Hameed (1), C. Schadt (2), D. Pelletier (2), A. Schaefer (3), G. Tuskan (2), J. Labbe (2), F. Martin (4), M. Doktycz (2), K. LaButti (5), R. Ohm (6), I. Grigoriev (6), R. Vilglays (1)
(1) Duke University, Durham, NC, U.S.A.; (2) Oak Ridge National Laboratory, Oak Ridge, TN, U.S.A.; (3) University of Washington, Seattle, WA, U.S.A.; (4) INRA, Nancy, France; (5) Department of Energy - LBL, Berkeley, CA, U.S.A.; (6) Joint Genome Institute, Walnut Creek, CA, U.S.A.

Mortierella elongata belongs to a group of basal fungi (Mortierellomycotina) and is commonly isolated from forest soils and healthy plant roots. Recent reports indicate that some isolates of M. elongata host endosymbiotic bacteria, but it is sunclear whether these are lineage-specific associations. Given the geographically widespread distribution of M. elongata and its ubiquitous presence in forest soils and plants we chose to sequence its genome through the JGI Forest Metatranscriptome CSP. We also sought to assemble the genome of the bacterial endosymbiont. The 50 Mb genome of M. elongata was sequenced to 112x coverage. Of the 220,113 putative proteins identified in M. elongata, only ~50% have orthologs in other fungal species having sequenced genomes). The M. elongata genome appears to be enriched in genes related to lipid metabolism (e.g. sphingolipids, etherlipids, and glycerophopholids), tryptophan metabolism, siderophore group nonribosomal peptides, and glucan 1,4-alpha glucosidases compared to genome sequences of other basal fungi. The endosymbiotic bacterium sequenced along with the M. elongata isolate is related to Glomeribacter (endosymbiont of Gigospora, Scutellospora) within the Burkholderiaceae. The ~2.6 MB endosymbiont genome is larger than that of Glomeribacter but reduced compared to free-living Burkholderia. Although many genes have been lost, some gene families have expanded including those involved in protein metabolism and electron transport.