Evidence for an enantioselective pumiliotoxin 7-hydroxylase in dendrobatid poison frogs of the genus Dendrobates

Supplemental Material for 'Phylogenetic systematics of dart-poison frogs and their relatives (Amphibia, Athesphatanura, Dendrobatidae). (Bulletin of the AMNH ; no. 299)'

“…Nevertheless, it is unclear how widespread metabolic conversion may be, as the following 12 alkaloid classes have been administered in feeding experiments with no evidence for any metabolism (J. W. Given the dietary origin of the alkaloids and how little is known about the alkaloid uptake system, we were conservative in delimiting alkaloid characters for phylogenetic analysis. Instead of coding the occurrence of each of the over 450 dendrobatid alkaloids as a separate character, we scored the occurrence of the major and minor classes of alkaloids, following Daly et al (1987Daly et al ( , 1993 and incorporating more recent developments (e.g., Daly et al, 1994cDaly et al, , 2003Daly et al, , 2005Daly, 1998;Garraffo et al, 1993Garraffo et al, , 1997Garraffo et al, , 2001Daly et al, 1999;Mortari et al, 2004; J. W. Daly, in litt., 01/25/05). We followed Myers (1987) and Myers et al (1995) in coding 3,5-indolizidines and 5,8-methylindolizidines as distinct characters.…”

“…Data were taken from reviews (Daly et al, 1987(Daly et al, , 1999, the primary literature (Tokuyama et al, 1992;Garraffo et al, 1993Garraffo et al, , 2001Badio and Daly, 1994;Myers et al, 1995;Daly et al, 1997Daly et al, ., 2003Fitch et al, 2003;Saporito et al, 2003;Mortari et al, 2004;Darst et al, 2005), and an exhaustive summary of published and unpublished alkaloid profiles and corrections to previous accounts provided by John W. Daly (in litt., 01/25/05). To facilitate coding from the literature we list the individual nonsteroidal alkaloids for each class, following the convention of Daly et al (1987).…”

Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics

“…Alkaloids are absent in dendrobatid and Mantella frogs raised in captivity on a diet of Drosophila, but these individuals will readily accumulate alkaloids added to their diet (10)(11)(12)(13)(14)(15). Some anurans also have the ability to modify ingested alkaloids: pumiliotoxin 307A was metabolized by one species of the genus Pseudophyrne (8), and pumiliotoxin (ϩ)-251D was efficiently and stereoselectively hydroxylated by Dendrobates spp.…”

“…Some anurans also have the ability to modify ingested alkaloids: pumiliotoxin 307A was metabolized by one species of the genus Pseudophyrne (8), and pumiliotoxin (ϩ)-251D was efficiently and stereoselectively hydroxylated by Dendrobates spp. into allopumiliotoxin (ϩ)-267A, which is five times more toxic (14). The only known example of direct alkaloid production is in the Australian Pseudophryne frogs, which seem to be capable of synthesizing indolic pseudophrynamines (8).…”

Convergent evolution of bright coloration and toxicity in frogs

“…Future research should focus on sampling the toxicity of a broader array of Colostethus species. Research to date has not revealed the presence of lipophilic alkaloids in any Colostethus (14) although one species has been demonstrated to have water-soluble skin toxins (15). However, a limited number of species have been sampled, and it would be useful to garner more information on the toxicity of cryptic dendrobatids, to conduct more thorough tests of the hypothesis of aposematism.…”