Elysia chlorotica

It seems that these unusual propionate metabolites might be taxonomical marker of many Elysioidea molluscs. In fact, they have also been found in Elysia chlorotica [61], where the enantiomer of deoxytridachione (14) co-occurs with elysione (16) ( = tridachiapyrone-A [62]) which could be the formal precursor of crispatene (17) found in populations of T. crispata from the Caribeean [58, 62]. It seems well supported that the ascoglossan-chloroplast pair is able to synthesize these molecules de novo, but further experiments with less general precursors need to ascertain the propionate origin. 

Dawe, R. D. andWright, J. L. C., The major polypropionate metabolites from the sacoglossan mollusc Elysia chlorotica, Tetrahedron Lett., 27, 2559, 1986. 

It has recently been shown that the nuclear gene of oxygenic photosynthesis, psbO, is transferred from the green alga Vaucheria litorea to the sea slug Elysia chlorotica (Rumpho et al, 2008). 

Rumpho, M.E., Worful, J.M., Lee, J., Kannan, K., Tyler, M.S., Bhattacharya, D., Moustafa, A., and Manhart, J.R. (2008) Horizontal gene transfer of the algal gene psbO to the photosynthetic sea slug Elysia chlorotica. Proc. Natl Acad. Sci. USA, 105, 17867-17871. 

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