Yang JC, Madupu R, Durkin AC, Ekborg NA, Pedamallu CS, Hostetler JB et al. The complete genome of Teredinibacter turnerae T7901: an intracellular endosymbiont of marine wood-boring bivalves (Shipworms). PLoS One 4: e6085

Ocean Genome Legacy Inc, Ipswich, MA, USA.
PLoS ONE (Impact Factor: 3.23). 02/2009; 4(7):e6085. DOI: 10.1371/journal.pone.0006085
Source: PubMed


Here we report the complete genome sequence of Teredinibacter turnerae T7901. T. turnerae is a marine gamma proteobacterium that occurs as an intracellular endosymbiont in the gills of wood-boring marine bivalves of the family Teredinidae (shipworms). This species is the sole cultivated member of an endosymbiotic consortium thought to provide the host with enzymes, including cellulases and nitrogenase, critical for digestion of wood and supplementation of the host's nitrogen-deficient diet. T. turnerae is closely related to the free-living marine polysaccharide degrading bacterium Saccharophagus degradans str. 2-40 and to as yet uncultivated endosymbionts with which it coexists in shipworm cells. Like S. degradans, the T. turnerae genome encodes a large number of enzymes predicted to be involved in complex polysaccharide degradation (>100). However, unlike S. degradans, which degrades a broad spectrum (>10 classes) of complex plant, fungal and algal polysaccharides, T. turnerae primarily encodes enzymes associated with deconstruction of terrestrial woody plant material. Also unlike S. degradans and many other eubacteria, T. turnerae dedicates a large proportion of its genome to genes predicted to function in secondary metabolism. Despite its intracellular niche, the T. turnerae genome lacks many features associated with obligate intracellular existence (e.g. reduced genome size, reduced %G+C, loss of genes of core metabolism) and displays evidence of adaptations common to free-living bacteria (e.g. defense against bacteriophage infection). These results suggest that T. turnerae is likely a facultative intracellular ensosymbiont whose niche presently includes, or recently included, free-living existence. As such, the T. turnerae genome provides insights into the range of genomic adaptations associated with intracellular endosymbiosis as well as enzymatic mechanisms relevant to the recycling of plant materials in marine environments and the production of cellulose-derived biofuels.

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    • "Furthermore, the second and third most abundant bins in 37B (Teredinibacter sp. and Sphingomonas sp.) were not observed in 37A. Note that the second most abundant species in 37B, Teredinibacter sp., is distantly related to Teredinibacter turnerae (with amino acid identity at 67.4%), an endosymbiotic cellulolytic gammaproteobacteria isolated from the gill tissue of a shipworm, Lyrodus pedicellatus[44]. "
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    • "separate from the other proteobacterial HU proteins such as those of E. coli and Pseudomonas aeruginosa. Of great interest is the sequence from the endosymbiotic marine proteobacterium Teredinibacter turnerae (Distel et al., 2002; Yang et al., 2009), which contains an N-terminal domain which is lysineand alanine-rich and consists of PAKK repeats, a feature very similar to that of GoN. The C-terminal types of Planctomycetes form a significant cluster away from GoN, superficially forming a clade with other bacteria from unique environments, such as the deep-branching T. maritima and Aquifex aeolicus, and also the green sulphur bacteria group. "
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    • "[6,7]. More recently, Saccharophagus degradans, Teredinibacter turnerae have emerged as strong examples of two well characterized marine bacterial species involved in polysaccharide degradation,, whole genome annotations have revealed an extensive repertoire of relevant functional genes [8,9]. There is a diversity of polysaccharide structures, sources in the marine environment, but cellulose is well represented, likely to persist in POM due to the recalcitrance imparted by its crystalline structure. "
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