Biochemical Taxonomy of South American Amphibians by Means of Skin Amines and Polypeptides

The distribution of various amines and polypeptides of the skin in 90 species of five frog families show general agreement with classifications based on other criteria. In particular, the skin biochemistry generally supports the subgeneric divisions of Leptodactylus based on secondary sex characters; the isolated position of Odontophrynus among the Cerato- phryidae indicated by serological evidence is supported; Phyllomedusa differs strongly from other hylid genera in its possession of large amounts of polypeptides; and the presence of bufotenine in Melanophryniscus confirms the assignment of the genus to the Bufonidae. There is great variation within and between species of Bufo in amounts of amines of the skin.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Biochemical Taxonomy of South American Amphibians by Means of Skin Amines and Polypeptides

The distribution of various amines and polypeptides of the skin in 90 species of five frog families show general agreement with classifications based on other criteria. In particular, the skin biochemistry generally supports the subgeneric divisions of Leptodactylus based on secondary sex characters; the isolated position of Odontophrynus among the Cerato- phryidae indicated by serological evidence is supported; Phyllomedusa differs strongly from other hylid genera in its possession of large amounts of polypeptides; and the presence of bufotenine in Melanophryniscus confirms the assignment of the genus to the Bufonidae. There is great variation within and between species of Bufo in amounts of amines of the skin.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Biochemical Taxonomy of South American Amphibians by Means of Skin Amines and Polypeptides

The distribution of various amines and polypeptides of the skin in 90 species of five frog families show general agreement with classifications based on other criteria. In particular, the skin biochemistry generally supports the subgeneric divisions of Leptodactylus based on secondary sex characters; the isolated position of Odontophrynus among the Cerato- phryidae indicated by serological evidence is supported; Phyllomedusa differs strongly from other hylid genera in its possession of large amounts of polypeptides; and the presence of bufotenine in Melanophryniscus confirms the assignment of the genus to the Bufonidae. There is great variation within and between species of Bufo in amounts of amines of the skin.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Isolation and Amino Acid Sequence of Physalaemin, the Main Active Polypeptide of the Skin of Physalaemus fuscumaculatus

Crude methanol extracts of fresh and dried skins of Physalaemus fuscumaculatus, a South American amphibian, were subjected successively to chromatography on alkaline alumina and to countercurrent distribution. The main active constituent of these extracts, the polypeptide physalaemin, was thus obtained in a pure form. Total and partial acid hydrolysis, fission with trypsin and chymotrypsin, and end-group determination experiments demonstrated that physalaemin is an endecapeptide having the following amino acid composition and sequence: Pyr-Ala-Asp(OH)-Pro-Asp(NH2)-Lys-Phe-Tyr-Gly-Leu-Met-NH2 Some anomalies in the trypsin and chymotrypsin fission of physalaemin are discussed, and the strict chemical resemblance between physalaemin and eledoisin is pointed out.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Occurrence of Bradykinin-Like Substances in the Amphibian Skin

Gli estrati di pelle di alcuni comuni anfibi nostrani (Rana esculenta, Rana temporaria) e, ancor più, di certi anfibi sudamericani del generePhyllomedusa contengono rilevanti quantitativi di polipeptidi bradichinino-simili. Negli estratti diPhyllomedusa sauvagi ne sono stati identificati almeno tre, a mezzo di una semplice cromatografia su colonna di allumina basica: polipeptide A, assai simile alla bradichinina per le sue proprietà farmacologiche; polipeptide B, dotato di prolungata ed intensa azione ipotensiva; polipeptide C, particolarmente attivo sull'ileo di cavia. Sono in corso ricerche dirette all'isolamento di questi polipeptidi e al chiarimento della loro struttura chimica.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Occurrence of candicine (p-HYDROXYPHENYLETHYLTRIMETHYLAMMONIUM) in extracts of the skin of <i>leptodactylus pentadactylus pentadactylus</i>

CANDICINE has been known for more than 30 years to be a natural constituent of some plants, more precisely of some Argentinian Cactaceae. The compound has now been found to occur in a vertebrate tissue also. The dry skin of five specimens of Leptodactylus pentadactylus pentadactylus, an Amazonium amphibian, was extracted twice with 70 per cent acetone. The combined extracts were concentrated under reduced pressure and the aqueous liquid shaken repeatedly with petroleum ether to remove fats. Then evaporation was continued and the syrupy residue taken up, by stirring, in 100 ml of 99 per cent ethanol. The liquid was then passed through a column of alkaline alumina. Elution was carried out with decreasing concentrations of ethanol, as described in detail in other papers. ’ The different eluates were suitably concentrated and then chromatographed on Whatman no. 1 paper.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Taxonomic and evolutionary significance of biogenic amines and polypeptides occurring in amphibian skin. I. Neotropical Leptodactylid frogs

Qualitative identification and quantitative estimation both of aromatic biogenic amines and pharmacologically active polypeptides in the skin of amphibians appear to offer a valuable contribution to studies in taxonomy and evolution of this vertebrate class. Several examples of the accordance of the biochemical data herein reported with the data of traditional taxonomy are described for the neotropical family of frogs Leptodactylidae, but particular emphasis is laid on the striking correspondence between the systemic distribution of the spectra of biogenic amines and morphological taxonomy which is demonstrated by the species of the genus Leptodactylus.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Occurrence of candicine (p-HYDROXYPHENYLETHYLTRIMETHYLAMMONIUM) in extracts of the skin of <i>leptodactylus pentadactylus pentadactylus</i>

CANDICINE has been known for more than 30 years to be a natural constituent of some plants, more precisely of some Argentinian Cactaceae. The compound has now been found to occur in a vertebrate tissue also. The dry skin of five specimens of Leptodactylus pentadactylus pentadactylus, an Amazonium amphibian, was extracted twice with 70 per cent acetone. The combined extracts were concentrated under reduced pressure and the aqueous liquid shaken repeatedly with petroleum ether to remove fats. Then evaporation was continued and the syrupy residue taken up, by stirring, in 100 ml of 99 per cent ethanol. The liquid was then passed through a column of alkaline alumina. Elution was carried out with decreasing concentrations of ethanol, as described in detail in other papers. ’ The different eluates were suitably concentrated and then chromatographed on Whatman no. 1 paper.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Taxonomic and Evolutionary Significance of Biogenic Amines and Polypeptides in Amphibian Skin. II. Toads of the Genera Bufo and Melanophryniscus

The value of the study of biogenic amines and active polypeptides of the amphibian skin in providing taxonomic evidence has been pointed in an earlier paper (Cei, Erspamer and Roseghini, 1967). The point was stressed that biochemical taxonomy, in its broadest sense, is possibly more discriminating than traditional taxonomy, based on somatic or osteological structures, size or coloration. In the first paper of this series sets of biochemical and pharmacological data concerning the skins of lep- todactylid frogs were reported and discussed. The present paper deals similarly with representatives of another very important family of Procoela, the Bufonidae.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse

Indole-, imidazole-, and phenyl-alkylamines in the skin of thirteen <i>Leptodactylus</i> species

The skin of thirteen Leptodactylus species and sub-species has been examined in regard to its content in biogenic amines. This tissue presents, especially in Leptodactylus pentadactylus labyrinthicus and some other species, an unusually rich miscellany of amines, including at least two indolealkylamines (5-hydroxytryptamine and bufotenidine), three hydroxyphenylalkylamines (p-tyramine, candicine, leptodactyline) and five imidazolealkylamines (histamine, N-methylhistamine, N,N-dimethylhistamine, spinaceamine and 6-methylspinaceamine). It is concluded that the Leptodactylus skin must possess aromatic acid decarboxylase activity, tryptophan-5-hydroxylase activity and N-methyltransferase activity. The skin of nearly every Leptodactylus species and sub-species is characterized by a particular spectrum of amines, which evidently may help in systematies of these species.Material digitalizado en SEDICI gracias a la colaboración del Dr. Jorge Williams (FCNM-UNLP).Facultad de Ciencias Naturales y Muse