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| Content Provider | PubMed Central |
|---|---|
| Author | Daly, John W. Garraffo, H. Martin Spande, Thomas F. Clark, Valerie C. Ma, Jingyuan Ziffer, Herman Cover, John F. |
| Copyright Year | 2003 |
| Abstract | Dendrobatid poison frogs readily accumulate alkaloids from diet into skin, where such compounds serve as a chemical defense against predators. Arthropods seem to be the source of decahydroquinolines (DHQs), several izidines, coccinellines, spiropyrrolizidines, pumiliotoxins (PTXs), and allopumiliotoxins (aPTXs). A DHQ iso-223F, and PTX (+)-251D were fed to poison frogs of the dendrobatid genera Dendrobates, Epipedobates, and Phyllobates. The two alkaloids were accumulated in skin unchanged except for the three species of Dendrobates, where ≈80% of accumulated PTX (+)-251D was stereoselectively hydroxylated to aPTX (+)-267A. The unnatural enantiomer PTX (-)-251D was accumulated efficiently when fed to Dendrobates auratus, but was not hydroxylated. The enantiomers of PTX 251D and their desmethyl analogs were synthesized from N-Boc-protected (-)- and (+)-proline methyl esters. Both PTX (+)-251D and aPTX (+)-267A proved to be potent convulsants in mice, with (+)-267A being ≈5-fold more toxic than (+)-251D. Both alkaloids were hyperalgesic at the site of injection. The unnatural PTX (-)-251D caused no overt effect in mice. Thus, the evolutionary development of a pumiliotoxin 7-hydroxylase would have provided frogs of the genus Dendrobates with a means of enhancing the antipredator potency of ingested PTXs. |
| Related Links | http://dx.doi.org/10.1073/pnas.1834430100 |
| Ending Page | 11097 |
| Page Count | 6 |
| Starting Page | 11092 |
| File Format | |
| ISSN | 00278424 |
| e-ISSN | 10916490 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Issue Number | 19 |
| Volume Number | 100 |
| Language | English |
| Publisher | National Academy of Sciences |
| Publisher Date | 2003-09-16 |
| Access Restriction | Open |
| Rights Holder | National Academy of Sciences |
| Subject Keyword | General Research in Higher Education |
| Content Type | Text |
| Resource Type | Article |
| Subject | Multidisciplinary |
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