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Reuber Albuquerque Brandao - One of the best experts on this subject based on the ideXlab platform.

  • the phylogenetic relationships of the charismatic poster frogs phyllomedusinae anura hylidae
    Cladistics, 2009
    Co-Authors: Julián Faivovich, Celio F B Haddad, Delio Baeta, Karlheinz Jungfer, Guilherme F R Alvares, Reuber Albuquerque Brandao, Christopher A Sheil, Laura Soledad Barrientos, Cesar L Barrioamoros, Carlos Alberto Gonçalves Cruz
    Abstract:

    The leaf or monkey frogs of the hylid subfamily Phyllomedusinae are a unique group of charismatic anurans. We present a molecular phylogenetic analysis that includes 45 of the 60 species of phyllomedusines using up to 12 genes and intervening tRNAs. The aims were to gain a better understanding of the phylogenetic position of Phrynomedusa, test the monophyly and explore the relationships among several putative lineages (Hylomantis, the H. buckleyi Group, Phasmahyla, the four species groups of Phyllomedusa, and the species of Phyllomedusa that remain unassigned to any group), and to examine the implications of our phylogeny for the evolution of several characters in phyllomedusines. The analyses resulted in a well-supported phylogenetic hypothesis that provides a historical framework for a discussion of the evolution of characters associated with reproductive biology, gliding behaviour, the physiology of waterproofing, and bioactive peptides. Implications include an earlier origin for eggless capsules than for leaf-folding behaviour during amplexus, two independent origins of gliding, and an earlier origin of reduction in evaporative water loss than uricotelism, which is a result that originally was predicted on the basis of physiology alone. Furthermore, our results support the prediction that bioactive peptides from different peptide families are to be expected in all species of Phyllomedusinae. Hylomantis (as recently redefined) is shown to be paraphyletic and the synonymy of Agalychnis is revised to remedy this problem by including both Hylomantis and Pachymedusa.  © The Willi Hennig Society 2009.

  • natural history of Phyllomedusa centralis bokermann 1965 anura hylidae phyllomedusinae tadpole and calls
    South American Journal of Herpetology, 2009
    Co-Authors: Reuber Albuquerque Brandao, Guilherme F R Alvares, Allan Crema, Glaucia J Zerbini
    Abstract:

    ABSTRACT. The tadpole and vocalizations of Phyllomedusa centralis are described based on individuals from the type locality, Chapada dos Guimaraes, State of Mato Grosso, Brazil. An opaque abdomen, upper jaw sheath medially higher, and an abundance of oral disc papillae characterize the tadpole of P. centralis. Phyllomedusa centralis, P. ayeaye, P. oreades, and P. megacephala are similar in inhabiting small streams, larvae with medially high upper jaws sheaths, spiracle opening free from body, and a ventral fin about three times deeper than the dorsal fin. The vocal repertoire of P. centralis consists of three different calls (“single call”, “compound call”, and ”response call”). These calls differ from those of other species of the hypochondrialis group by their low dominant frequency, short note duration, and broad frequency range with minimum (fundamental) and maximum frequencies coincident with the dominant frequency.

  • Remarks on A new Phyllomedusa Wagler (Anura, Hylidae) with reticulated pattern on flanks from Southeastern Brazil
    Zootaxa, 2009
    Co-Authors: Reuber Albuquerque Brandao, Guilherme F R Alvares
    Abstract:

    Some species in the Phyllomedusa hypochondrialis species group have a reticulated pattern on the hidden parts of the flanks and limbs. These species are quite interesting given their characteristic distribution on mountain ranges, reproduction occurring in streams and rivulets, and by the surprising richness of the group. Four new species of Phyllomedusa were described in the last five years; three were species with reticulated pattern on flanks, endemic to restricted mountain ranges (Brandão 2002, Caramaschi et al., 2006, Giaretta et al., 2007). The most recently described species is Phyllomedusa araguari (Giaretta et al., 2007). However, some information reported in this description in relation to the original description of Phyllomedusa oreades (Brandão 2002) deserves further comments. Phyllomedusa araguari was described based on only three individuals and the authors stated that it can be easily distinguished from the very similar P. oreades by: 1) the presence of a reticulated pattern bordering the upper jaw and encircling the eyes (absent in P. oreades), 2) by having a broader reticulated strip in flanks, 3) a well defined reticulated pattern on throat, belly and ventral surfaces of limbs, 4) less projected nostrils, and 5) white ventral surface in life (pink in P. oreades). Phyllomedusa araguari was also reported as a pond breeder, while P. oreades is a stream breeder.

  • dermaseptins from Phyllomedusa oreades and Phyllomedusa distincta anti trypanosoma cruzi activity without cytotoxicity to mammalian cells
    Journal of Biological Chemistry, 2002
    Co-Authors: Guilherme D Brand, Jose Roberto S A Leite, Luciano P Silva, Maura V Prates, Ricardo B Azevedo, Sergio De Albuquerque, Vanessa Carregaro, Joao S Silva, Vanuza C L Sa, Reuber Albuquerque Brandao
    Abstract:

    Abstract Amphibian skin secretions are known as a rich source of biologically active molecules, most of which are alkaloids, biogenic amines, and peptides. Dermaseptins are a class of antimicrobial peptides present in tree frogs of thePhyllomedusa genus. They are cationic molecules of 28–34 residues that permeabilize the membrane of Gram-positive and Gram-negative bacteria, yeasts, and filamentous fungi, showing little or no hemolytic activity. This work reports the isolation, molecular mass analysis, primary structure determination, biological activities, and potential therapeutic applications of an antimicrobial peptide found in the skin secretion of Phyllomedusa oreades, which is a newly described amphibian species endemic of the Brazilian savanna. DS 01 is a 29-residue-long peptide with a molecular mass of 2793.39 Da showing antibacterial properties against Gram-positive and Gram-negative bacteria in the range of 3–25 μm. Anti-protozoan activity was investigated using T. cruzi in its trypomatigote and epimastigote forms cultivated in both cell culture and blood media. Within 2 h after incubation with DS 01 at a final concentration of ∼6 μm, no protozoan cells were detected. Two synthetic dermaseptins, described previously by our group and named dermadistinctins K and L (DD K and DD L), also had their anti-Trypanosoma cruzi activity investigated and demonstrated similar properties. Toxicity of DS 01 to mouse erythrocytes and white blood cells was evaluated by means of atomic force microscopy and flow cytometry. No morphological alterations were observed at a lytic concentration of DS 01, suggesting its therapeutic value especially as an anti-T. cruzi agent to prevent infections during blood transfusion.

  • a new species of Phyllomedusa wagler 1830 anura hylidae from central brazil
    Journal of Herpetology, 2002
    Co-Authors: Reuber Albuquerque Brandao
    Abstract:

    Abstract A new species of Phyllomedusa, related to Phyllomedusa megacephala, is described from the high plateaus of the state of Goias and Distrito Federal, Brazil. The new species is characterized by medium size, small finger pads, short and narrow head, thin body, vertical snout in profile, very granulate belly, chest without reticular pattern, transversal bars in the mandible, and flanks with reticular black, sepia, or purple pattern over yellow or orange background.

C Shaw - One of the best experts on this subject based on the ideXlab platform.

  • discovery of phylloseptins that defense against gram positive bacteria and inhibit the proliferation of the non small cell lung cancer cell line from the skin secretions of Phyllomedusa frogs
    Molecules, 2017
    Co-Authors: Qing Wu, C Shaw, Tianbao Chen, Lei Li, Xinping Xi, Di Wu, Mei Zhou, Lei Wang
    Abstract:

    The growing occurrence of bacterial resistance to conventional antibiotics has called for the development of new classes of antimicrobial agents. Antimicrobial peptides (AMPs) with broad antimicrobial spectrum derived from frog skin secretions have been demonstrated to be promising candidates for new antibiotic development. A proven rich source of these compounds are the skin secretions of the frogs in the Phyllomedusa genus. In this study, two novel phylloseptin peptides—phylloseptin-PTa and phylloseptin-PHa—were isolated from the skin secretions of the South American frogs, Phyllomedusa tarsius (P. tarsius) and Phyllomedusa hypochondrialis (P. hypochondrialis) through parallel transcriptomic and peptidomic studies. Replicates obtained by chemical synthesis were structurally analysed and shown to adopt an α-helix configuration in an amphiphilic environment. Both peptides demonstrated antimicrobial activities against planktonic Gram-positive bacteria strains, including Staphylococcus aureus, Enterococcus faecalis and methicillin-resistant Staphylococcus aureus , biofilms, as well as cytostatic effects on the non-small cell lung cancer cell line, NCI-H157, with relatively low haemolysis on horse erythrocytes and low cytotoxicity on the human microvascular endothelial cell line, HMEC-1. The discovery of phylloseptin peptides may further inspire the development of new types of antibiotics.

  • discovery of novel bacterial cell penetrating phylloseptins in defensive skin secretions of the south american hylid frogs Phyllomedusa duellmani and Phyllomedusa coelestis
    Toxins, 2016
    Co-Authors: Nan Yang, Tianbao Chen, Lei Li, Xinping Xi, Di Wu, Mei Zhou, Lei Wang, C Shaw
    Abstract:

    Phylloseptin (PS) peptides, derived from South American hylid frogs (subfamily Phyllomedusinae), have been found to have broad-spectrum antimicrobial activities and relatively low haemolytic activities. Although PS peptides have been identified from several well-known and widely-distributed species of the Phyllomedusinae, there remains merit in their study in additional, more obscure and specialised members of this taxon. Here, we report the discovery of two novel PS peptides, named PS-Du and PS-Co, which were respectively identified for the first time and isolated from the skin secretions of Phyllomedusa duellmani and Phyllomedusa coelestis. Their encoding cDNAs were cloned, from which it was possible to deduce the entire primary structures of their biosynthetic precursors. Reversed-phase high-performance liquid chromatography (RP-HPLC) and tandem mass spectrometry (MS/MS) analyses were employed to isolate and structurally-characterise respective encoded PS peptides from skin secretions. The peptides had molecular masses of 2049.7 Da (PS-Du) and 1972.8 Da (PS-Co). They shared typical N-terminal sequences and C-terminal amidation with other known phylloseptins. The two peptides exhibited growth inhibitory activity against E. coli (NCTC 10418), as a standard Gram-negative bacterium, S. aureus (NCTC 10788), as a standard Gram-positive bacterium and C. albicans (NCPF 1467), as a standard pathogenic yeast, all as planktonic cultures. Moreover, both peptides demonstrated the capability of eliminating S. aureus biofilm.

  • baltikinin a new myotropic tryptophyllin 3 peptide isolated from the skin secretion of the purple sided leaf frog Phyllomedusa baltea
    Toxins, 2016
    Co-Authors: Xinping Xi, Tianbao Chen, Mei Zhou, Lei Wang, Hang Chen, C Shaw
    Abstract:

    Here we report the identification of a novel tryptophyllin-3 peptide with arterial smooth muscle relaxation activity from the skin secretion of the purple-sided leaf frog, Phyllomedusa baltea. This new peptide was named baltikinin and had the following primary structure, pGluDKPFGPPPIYPV, as determined by tandem mass spectrometry (MS/MS) fragmentation sequencing and from cloned skin precursor-encoding cDNA. A synthetic replicate of baltikinin was found to have a similar potency to bradykinin in relaxing arterial smooth muscle (half maximal effective concentration (EC50) is 7.2 nM). These data illustrate how amphibian skin secretions can continue to provide novel potent peptides that act through functional targets in mammalian tissues.

  • ph sauvagine from the skin secretion of Phyllomedusa hypochondrialis a novel crf like peptide with smooth muscle contraction activity
    Toxicon, 2015
    Co-Authors: Yu Zhou, C Shaw, Tianbao Chen
    Abstract:

    Amphibian skin, and particularly that of south/Central American phyllomedusine frogs, is supposed to be “a huge factory and store house of a variety of active peptides”. The 40 amino acid amphibian CRF-like peptide, sauvagine, is a prototype member of a unique family of these Phyllomedusa skin peptides. In this study, we describe for the first time the structure of a mature novel peptide from the skin secretion of the South American orange-legged leaf frog, Phyllomedusa hypochondrialis, which belongs to the amphibian CRF/sauvagine family. Partial amino acid sequence from the N-terminal was obtained by automated Edman degradation with the following structure: pGlu-GPPISIDLNMELLRNMIEI-. The biosynthetic precursor of this novel sauvagine peptide, consisted of 85 amino acid residues and was deduced from cDNA library constructed from the same skin secretion. Compared with the standard sauvagine from the frog, Phyllomedusa sauvagei, this novel peptide was found to exert similar contraction effects on isolated guinea-pig colon and rat urinary bladder smooth muscle preparations.

  • balteatide a novel antimicrobial decapeptide from the skin secretion of the purple sided leaf frog Phyllomedusa baltea
    The Scientific World Journal, 2014
    Co-Authors: Lilin Ge, Tianbao Chen, Xinping Xi, Mei Zhou, Lei Wang, Xiaole Chen, Anwei Ding, Jinao Duan, C Shaw
    Abstract:

    The skin secretions of Neotropical phyllomedusine leaf frogs have proven to be a rich source of biologically active peptides, including antimicrobials. The major families of antimicrobial peptides (AMPs) reported are the dermaseptins and phylloseptins and the minor families are the dermatoxins, phylloxins, plasticins, distinctins, and medusins. Here, we report a novel AMP of 10 amino acid residues (LRPAILVRIKamide), named balteatide, from the skin secretion of wild Peruvian purple-sided leaf frogs, Phyllomedusa baltea. Balteatide was found to exhibit a 90% sequence identity with sauvatide, a potent myotropic peptide from the skin secretion of Phyllomedusa sauvagei. However, despite both peptides exhibiting only a single amino acid difference (I/T at position 9), sauvatide is devoid of antimicrobial activity and balteatide is devoid of myotropic activity. Balteatide was found to have differential activity against the Gram-positive bacterium, Staphylococcus aureus; the Gram-negative bacterium, Escherichia coli; and the yeast, Candida albicans, and unusual for phyllomedusine frog skin AMPs, was most potent (MIC 32 mg/L) against the yeast. Balteatide was also devoid of haemolytic activity up to concentrations of 512 mg/L. Phyllomedusine frog skin secretions thus continue to provide novel AMPs, some of which may provide templates for the rational design of new classes of anti-infective therapeutics.

V Erspamer - One of the best experts on this subject based on the ideXlab platform.

Tianbao Chen - One of the best experts on this subject based on the ideXlab platform.

  • discovery of phylloseptins that defense against gram positive bacteria and inhibit the proliferation of the non small cell lung cancer cell line from the skin secretions of Phyllomedusa frogs
    Molecules, 2017
    Co-Authors: Qing Wu, C Shaw, Tianbao Chen, Lei Li, Xinping Xi, Di Wu, Mei Zhou, Lei Wang
    Abstract:

    The growing occurrence of bacterial resistance to conventional antibiotics has called for the development of new classes of antimicrobial agents. Antimicrobial peptides (AMPs) with broad antimicrobial spectrum derived from frog skin secretions have been demonstrated to be promising candidates for new antibiotic development. A proven rich source of these compounds are the skin secretions of the frogs in the Phyllomedusa genus. In this study, two novel phylloseptin peptides—phylloseptin-PTa and phylloseptin-PHa—were isolated from the skin secretions of the South American frogs, Phyllomedusa tarsius (P. tarsius) and Phyllomedusa hypochondrialis (P. hypochondrialis) through parallel transcriptomic and peptidomic studies. Replicates obtained by chemical synthesis were structurally analysed and shown to adopt an α-helix configuration in an amphiphilic environment. Both peptides demonstrated antimicrobial activities against planktonic Gram-positive bacteria strains, including Staphylococcus aureus, Enterococcus faecalis and methicillin-resistant Staphylococcus aureus , biofilms, as well as cytostatic effects on the non-small cell lung cancer cell line, NCI-H157, with relatively low haemolysis on horse erythrocytes and low cytotoxicity on the human microvascular endothelial cell line, HMEC-1. The discovery of phylloseptin peptides may further inspire the development of new types of antibiotics.

  • discovery of novel bacterial cell penetrating phylloseptins in defensive skin secretions of the south american hylid frogs Phyllomedusa duellmani and Phyllomedusa coelestis
    Toxins, 2016
    Co-Authors: Nan Yang, Tianbao Chen, Lei Li, Xinping Xi, Di Wu, Mei Zhou, Lei Wang, C Shaw
    Abstract:

    Phylloseptin (PS) peptides, derived from South American hylid frogs (subfamily Phyllomedusinae), have been found to have broad-spectrum antimicrobial activities and relatively low haemolytic activities. Although PS peptides have been identified from several well-known and widely-distributed species of the Phyllomedusinae, there remains merit in their study in additional, more obscure and specialised members of this taxon. Here, we report the discovery of two novel PS peptides, named PS-Du and PS-Co, which were respectively identified for the first time and isolated from the skin secretions of Phyllomedusa duellmani and Phyllomedusa coelestis. Their encoding cDNAs were cloned, from which it was possible to deduce the entire primary structures of their biosynthetic precursors. Reversed-phase high-performance liquid chromatography (RP-HPLC) and tandem mass spectrometry (MS/MS) analyses were employed to isolate and structurally-characterise respective encoded PS peptides from skin secretions. The peptides had molecular masses of 2049.7 Da (PS-Du) and 1972.8 Da (PS-Co). They shared typical N-terminal sequences and C-terminal amidation with other known phylloseptins. The two peptides exhibited growth inhibitory activity against E. coli (NCTC 10418), as a standard Gram-negative bacterium, S. aureus (NCTC 10788), as a standard Gram-positive bacterium and C. albicans (NCPF 1467), as a standard pathogenic yeast, all as planktonic cultures. Moreover, both peptides demonstrated the capability of eliminating S. aureus biofilm.

  • baltikinin a new myotropic tryptophyllin 3 peptide isolated from the skin secretion of the purple sided leaf frog Phyllomedusa baltea
    Toxins, 2016
    Co-Authors: Xinping Xi, Tianbao Chen, Mei Zhou, Lei Wang, Hang Chen, C Shaw
    Abstract:

    Here we report the identification of a novel tryptophyllin-3 peptide with arterial smooth muscle relaxation activity from the skin secretion of the purple-sided leaf frog, Phyllomedusa baltea. This new peptide was named baltikinin and had the following primary structure, pGluDKPFGPPPIYPV, as determined by tandem mass spectrometry (MS/MS) fragmentation sequencing and from cloned skin precursor-encoding cDNA. A synthetic replicate of baltikinin was found to have a similar potency to bradykinin in relaxing arterial smooth muscle (half maximal effective concentration (EC50) is 7.2 nM). These data illustrate how amphibian skin secretions can continue to provide novel potent peptides that act through functional targets in mammalian tissues.

  • ph sauvagine from the skin secretion of Phyllomedusa hypochondrialis a novel crf like peptide with smooth muscle contraction activity
    Toxicon, 2015
    Co-Authors: Yu Zhou, C Shaw, Tianbao Chen
    Abstract:

    Amphibian skin, and particularly that of south/Central American phyllomedusine frogs, is supposed to be “a huge factory and store house of a variety of active peptides”. The 40 amino acid amphibian CRF-like peptide, sauvagine, is a prototype member of a unique family of these Phyllomedusa skin peptides. In this study, we describe for the first time the structure of a mature novel peptide from the skin secretion of the South American orange-legged leaf frog, Phyllomedusa hypochondrialis, which belongs to the amphibian CRF/sauvagine family. Partial amino acid sequence from the N-terminal was obtained by automated Edman degradation with the following structure: pGlu-GPPISIDLNMELLRNMIEI-. The biosynthetic precursor of this novel sauvagine peptide, consisted of 85 amino acid residues and was deduced from cDNA library constructed from the same skin secretion. Compared with the standard sauvagine from the frog, Phyllomedusa sauvagei, this novel peptide was found to exert similar contraction effects on isolated guinea-pig colon and rat urinary bladder smooth muscle preparations.

  • balteatide a novel antimicrobial decapeptide from the skin secretion of the purple sided leaf frog Phyllomedusa baltea
    The Scientific World Journal, 2014
    Co-Authors: Lilin Ge, Tianbao Chen, Xinping Xi, Mei Zhou, Lei Wang, Xiaole Chen, Anwei Ding, Jinao Duan, C Shaw
    Abstract:

    The skin secretions of Neotropical phyllomedusine leaf frogs have proven to be a rich source of biologically active peptides, including antimicrobials. The major families of antimicrobial peptides (AMPs) reported are the dermaseptins and phylloseptins and the minor families are the dermatoxins, phylloxins, plasticins, distinctins, and medusins. Here, we report a novel AMP of 10 amino acid residues (LRPAILVRIKamide), named balteatide, from the skin secretion of wild Peruvian purple-sided leaf frogs, Phyllomedusa baltea. Balteatide was found to exhibit a 90% sequence identity with sauvatide, a potent myotropic peptide from the skin secretion of Phyllomedusa sauvagei. However, despite both peptides exhibiting only a single amino acid difference (I/T at position 9), sauvatide is devoid of antimicrobial activity and balteatide is devoid of myotropic activity. Balteatide was found to have differential activity against the Gram-positive bacterium, Staphylococcus aureus; the Gram-negative bacterium, Escherichia coli; and the yeast, Candida albicans, and unusual for phyllomedusine frog skin AMPs, was most potent (MIC 32 mg/L) against the yeast. Balteatide was also devoid of haemolytic activity up to concentrations of 512 mg/L. Phyllomedusine frog skin secretions thus continue to provide novel AMPs, some of which may provide templates for the rational design of new classes of anti-infective therapeutics.

Pier Carlo Montecucchi - One of the best experts on this subject based on the ideXlab platform.