Green sea slug makes chlorophyll like a plant

Jan 12, 2010 by Lin Edwards report
The photosynthetic sea slug Elysia chlorotica appears like a dark green leaf as a result of retaining chloroplasts from its algal prey, Vaucheria litorea, in cells lining its digestive tract. Image credit: Mary S. Tyler/PNAS.

(PhysOrg.com) -- Scientists from the University of South Florida in Tampa have found a green sea slug is able to synthesize chlorophyll like a plant, which makes it the first animal known to be capable of the feat.

Researcher Sidney K. Pierce said the super green , Elysia chlorotica, which lives in waters on the east coast of the USA and Canada, is known to steal genes and photosynthesizing organelles called chloroplasts from its favorite intertidal algae species, Vaucheria litorea, but it now seems it has developed an entire chemical pathway to manufacture the green pigment " a" itself.

Chlorophyll is the pigment that captures energy from in . Pierce and his team used radioactive tracing techniques to determine the slugs were manufacturing the chlorophyll themselves and it did not originate in the algae they ate.

A number of animals (such as corals) host microbes and algae and benefit from their photosynthesis, but in most of these associations the cells remain whole. In Elysia chlorotica, in contrast, the cells are broken down and chloroplasts are extracted and held inside the slug's own cells, where they remain active for the slug's lifetime of almost a year. Researchers have shown that once a young slug has eaten a meal of Vaucheria algae it never has to eat again as long as it has access to light and supplies of chlorophyll and other chemicals used in photosynthesis.

In 2007 scientists, including Pierce and his team, found genes related to photosynthesis in the slugs, and these genes, apparently originally from the algae, were even found in unhatched slugs that had never eaten algae. In the latest research Pierce found more algal genes, and some of them were for enzymes required for the chemical process manufacturing chlorophyll.

Pierce and his team studied slugs that had not eaten anything for at least five months and had stopped eliminating waste digestive products. They contained chloroplasts taken from the algae, but Pierce said that any other part of the should have long ago been digested. They gave the slug an amino acid labeled with radioactive carbon and found that the radioactive carbon turned up in the chlorophyll a molecule after the slugs had been sunbathing, but not if they had been in the dark.

The findings were reported at the annual meeting of the Society for Integrative and Comparative Biology in Seattle, Washington on 7 January and will be published in the journal Symbiosis.

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Husky
3 / 5 (2) Jan 12, 2010
It would be a great accomplishment if photosynthesis ultimately could be introduced higher up the foodchain in e.d. fish, just think of the prospects for fishfarms, could be operating on halve the feedstock
superhuman
3 / 5 (2) Jan 12, 2010
Forget fishfarms, I want to photosynthesize myself.
antialias
4 / 5 (4) Jan 12, 2010
We humans require a bit more energy than could be harnessed by photosynthesis (even if we were to cover ourselves fully in the stuff or even if 100% of the sun's energy impacting on us could be converted to energy)

(There's a reason why plants are 'slow' and we can move about quickly and keep our body temperature and use a lot of energy for our brains, etc. )

So don't expect genetic-engineering to produce a 'photosythetic fish' (which would be pretty stupid, anyways, since fish live usually below water where energy from the radiation rapidly drops to next to nothing)
david13579
1 / 5 (1) Jan 12, 2010
Wikipedia says this has been known for a while so why is it treated as new here? http://en.wikiped...toplasty
frajo
3.7 / 5 (3) Jan 13, 2010
Wikipedia says this has been known for a while so why is it treated as new here?
It is new that the algae plastids are not only eaten and maintained functionally intact within Elysia chlorotica. They are also actively reproduced by the genetical apparatus of Elysia chlorotica. The genes
were even found in unhatched slugs that had never eaten algae.

Eco_R1
2.5 / 5 (2) Jan 13, 2010
Screw that i want invivo fementation, so i can just sit there and get pissed
fourthrocker
5 / 5 (3) Jan 14, 2010
When I was a kid I had a microscope and spent many hours looking at pond water. One time I saw something shaped like a ping pong paddle. The paddle part had a twist and the handle went to a point. It was cork-screwing through the water. It was chlorophyl green. I only saw it for a few seconds because it was moving and then I lost it. This thing was moving under it's own power and looked like it was a plant. Anyone know what it was?
PinkElephant
4 / 5 (4) Jan 14, 2010
Screw that i want invivo fementation, so i can just sit there and get pissed


This actually happens in real life. Back in college, a professor once related a "funny" anecdote about a guy who lost his job, then his wife and family, for being chronically drunk, yet he claimed to never drink anything alcoholic (of course, nobody believed him.) Later, they found he had a bacterial infection in his gut, that was manufacturing alcohol from food sugars... Fiction, meet reality. =) I don't have the source of that exact story, but you can see some examples by googling "Intragastrointestinal Alcohol Fermentation Syndrome"
PinkElephant
5 / 5 (3) Jan 14, 2010
@superhuman,

Forget fishfarms, I want to photosynthesize myself.


What better excuse for a world-wide adoption of nudism :-)

Talk about "little green men"...

Would certainly send religious fundamentalists into transports of whatever...

Hah, sounds like fun. Sign me up! :)
madrigal
5 / 5 (2) Jan 20, 2010
When I was a kid I had a microscope and spent many hours looking at pond water. One time I saw something shaped like a ping pong paddle. The paddle part had a twist and the handle went to a point. It was cork-screwing through the water. It was chlorophyl green. I only saw it for a few seconds because it was moving and then I lost it. This thing was moving under it's own power and looked like it was a plant. Anyone know what it was?


It was most-likely a Euglena spp. remarkable creatures! Just for the record I had a microscope when I was a kid, I have a few now, a bit bigger, and I still have the same enthusiasm I had as a child when taking time out and looking at pond water!

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