# Source of pumilio toxins



## doncoyote (Apr 20, 2005)

According to a team from NIH, it's mites: http://www.newscientist.com/article/dn11855-mites-give-poison-frogs-their-toxic-might.html.


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## AJ_Cann (Oct 6, 2004)

Doh! beat me to it!

http://www.pnas.org/cgi/content/abstract/0702851104v1
Alkaloids in the skin glands of poison frogs serve as a chemical defense against predation, and almost all of these alkaloids appear to be sequestered from dietary arthropods. Certain alkaloid-containing ants have been considered the primary dietary source, but dietary sources for the majority of alkaloids remain unknown. Herein we report the presence of 80 alkaloids from extracts of oribatid mites collected throughout Costa Rica and Panama, which represent 11 of the 24 structural classes of alkaloids known in poison frogs. Forty-one of these alkaloids also occur in the dendrobatid poison frog, Oophaga pumilio, which co-occurs with the collected mites. These shared alkaloids include twenty-five 5,8-disubstituted or 5,6,8-trisubstituted indolizidines; one 1,4-disubstituted quinolizidine; three pumiliotoxins; and one homopumiliotoxin. All but the last of these alkaloid classes occur widely in poison frogs. In addition, nearly 40 alkaloids of unknown structure were detected in mites; none of these alkaloids have been identified in frog extracts. Two of these alkaloids are homopumiliotoxins, five appear to be izidines, four appear to be tricyclics, and six are related in structure to poison frog alkaloids that are currently unclassified as to structure. Mites are common in the diet of O. pumilio, as well as in the diets of other poison frogs. The results of this study indicate that mites are a significant arthropod repository of a variety of alkaloids and represent a major dietary source of alkaloids in poison frogs.

http://www.newscientist.com/article.ns?id=dn11855


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## geedubya (Mar 16, 2006)

*Mites, not ants, the source of dart frog's poison.*

Mites, not ants, the source of dart frog's poison.

Article from National Geographic
http://news.nationalgeographic.com/news ... frogs.html


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## Jungle_John (Feb 19, 2007)

good artical


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## rozdaboff (Feb 27, 2005)

This was posted a few months back - so I merged the two. Check out the full length PNAS article if you can.


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## geedubya (Mar 16, 2006)

*National Geographic Article*

Well, that's me! Day late, dollar short.
:?
Gary


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## KeroKero (Jun 13, 2004)

I don't know if it's really "Mites, not ants..." as much as ants for one population, mites for another, beetles for another... or variations of all three across the board.


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## CanadianScientist (Sep 15, 2007)

You know, i was always under the suspicion that it was indeed like that as well Kero, alittle bit from a broad range of prey


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## KeroKero (Jun 13, 2004)

These frogs have a range of toxins, and they can vary from population to population... theorized that it varies from available food sources. It's cool for them to find another source for one of (the many) toxins, but it's hardly the case that they eat one specific invert and get all it's toxins there, as some people believe the way the articles may be written. It's cool to find another peice of the puzzle tho!


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## MonarchzMan (Oct 23, 2006)

KeroKero said:


> I don't know if it's really "Mites, not ants..." as much as ants for one population, mites for another, beetles for another... or variations of all three across the board.


My thoughts exactly. I doubt a pumilio will pass up an ant or a millipede or a beetle when given the chance.


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## bbrock (May 20, 2004)

MonarchzMan said:


> KeroKero said:
> 
> 
> > I don't know if it's really "Mites, not ants..." as much as ants for one population, mites for another, beetles for another... or variations of all three across the board.
> ...


Correct me if I'm wrong, but I think the ants that were found to contain a similar toxin to some pdf were found somewhere like Puerto Rico or somewhere far from where pdf actually live. This led to seculation there may be ants near pdf supplying similar toxins. Have those been found yet? I believe ants and other arthropods have been tested and no toxin matches found with these pumilio on the studies. Ants keep coming up as a source. But unless there is a paper I missed (which is very possible), there is good reason to hypothesize ants as a potential source, but no evidence to take that beyond hypothesis while much firmer evidence is being gathered for soil arthropods, predominantly mites, and beetles. I'm not suggesting that ants can't be a source. I'm only trying to connect the dots of where the scientific evidence actually leads us. If I'm missing a dot, could someone let me know?


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## *GREASER* (Apr 11, 2004)

I think that the whole ant theory just got blown out of perportion. Its just out dated and people just hear these things some place and keep the urban legend or should I say jungle legend going. In the wild you see them eating tons of little things you can even see, MITES. Same with the pumilio in our tanks. You see them eating tons of mites.


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## KeroKero (Jun 13, 2004)

I don't recall the ant paper, but the beetle reference was a hypothesis about amphibians (or birds, I need to look it up) using toxins from beetles they have eaten to develop their own toxins, like PDFs. These beetles, which contained a toxic known in PDFs, have a world wide (or atleast australian/latin american) distribution, leading to the hypothesis that other members of that beetle taxon could be supplying PDFs with toxins.


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## Ben_C (Jun 25, 2004)

Perhaps not THE ant paper, but an ant paper...
Saporito, RA,Garraffo HM, Donnelly, MA, Edwards, AL, Longino, JT and Daly JW 2004. Formicine ants: An arthropod source for the pumiliotoxin alkaloids of dendrobatid poison frogs. PNAS 101(21): 8045-8050.



> but the beetle reference was a hypothesis about amphibians (or birds, I need to look it up) using toxins from beetles they have eaten to develop their own toxins, like PDFs


Dumbacher JP, Spande TF, and Daly JW. 2000. Batrachotoxin alkaloids from passerine birds: A second toxic bird genus (Ifrita kowaldi) from New Guinea. PNAS 97(24): 12970-12975 

Dumbacher JP, Wako A, Derrickson SR, Samuelson A, Spande TF, and Daly JW. 2004. Melyrid beetles (Choresine): A putative source for the batrachotoxin alkaloids found in poison-dart frogs and toxic passerine birds. PNAS 101(45): 15857-15860.

However, both of these references are discussing batrachotoxin (BTX) and not a Pumiliotoxin (PTX). 
Also, note that there are more than 100 PTXs in that have been documented thus far and therefore are likely from 100+ sources and so saying, "Ants are the source of PTX" or "Mites are the source of PTX" could be referring to completely different compounds.
Dendrobatids also modify potential toxins 'in house.' See the below reference:
Daly JW, Garraffo HM, Spande TF, Clark VC , Ma J, H Ziffer, Cover JF.
2003. Evidence for an enantioselective pumiliotoxin 7-hydroxylase in dendrobatid poison frogs of the genus Dendrobates. PNAS 100(19): 11092-11097.


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## KeroKero (Jun 13, 2004)

It's kinda like saying this critter is THE source for THE poison... there are many, many toxins involved there  The Ifrita were the birds I was thinking of, very cool.


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## Afemoralis (Mar 17, 2005)

Here is the other "ant paper": 

Caldwell, J. P. (1996). "The evolution of myrmecophagy and its correlates in poison frogs (Family Dendrobatidae)." J. Zool., Lond.(240): 75-101.

Not outdated in my book.

-Afemoralis


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## bbrock (May 20, 2004)

Afemoralis said:


> Here is the other "ant paper":
> 
> Caldwell, J. P. (1996). "The evolution of myrmecophagy and its correlates in poison frogs (Family Dendrobatidae)." J. Zool., Lond.(240): 75-101.
> 
> ...



Was that Jan Caldwell? Anyone have a pdf of this paper I might get hold of?


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## Ben_C (Jun 25, 2004)

> Was that Jan Caldwell? Anyone have a pdf of this paper I might get hold of?


Yes and yes.
I will e-mail it to you tomorrow, assuming:
a) I remember
b) I can find it

~B


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## bbrock (May 20, 2004)

Thanks for sending the paper Ben. 

I spent an afternoon with Jan once. She's a brilliant and fascinating scientist. Unfortunately though, I don't think this paper provides a lot of support for the ant hypothesis.

Basically, this paper provides data that shows that as the percentage of ants in a frog's diet goes up, so does there toxicity. The paper the presents a line of logic that says: frogs that eat a high percentage of ants are more toxic than frogs that eat a low percentage; many ants are known to contain alkaloids; therefore, ants may be the source of alkaloids for frogs. It's a nice hypothesis, but given the large amount of research done since this paper was published, it is not well supported. At best, ants are only one, among many, potential sources for alkaloids for frogs.

However, this isn't the paper I was thinking about earlier. I believe there was a paper published that found an alkaloid in an ant that closely matched one of the major alkaloids associated with dendrobatids. But the ant was found outside of any dendrobatid species range. If I'm remembering correctly, it was similar to the mylerid beetle paper except with mylerids, they actually showed a likely link between alkaloids in the beetle and it being the probable source of alkaloids in the pitouhi bird. Interestingly, the local natives had known about the source of the bird's toxins for a long time. No surprise there.


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## Ben_C (Jun 25, 2004)

> Thanks for sending the paper Ben.


You're very welcome.

I'll keep looking for this paper you're talking about and send it if i can find it.
Here are a couple others people may be interested in...
Smith S.Q., Jones T.H. 2004. Tracking the Cryptic Pumiliotoxins. PNAS. 101(21):7841-7842

And...

Tappey H. Jones, Jeffrey S. T. Gorman, Roy R. Snelling, Jacques H. C. Delabie, Murray S. Blum, H. Martin Garraffo, Poonam Jain5, John W. Daly and Thomas F. Spande. 1999. Further Alkaloids Common to Ants and Frogs: Decahydroquinolines and a Quinolizidine. Journal of Chemical Ecology. 25(5): 1179-1193

~B


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