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Recommendations of generic names in Diaporthales competing for protection or use.
Full text linkIn advancing to one name for fungi, this paper treats generic names competing for use in the order Diaporthales (Ascomycota, Sordariomycetes) and makes a recommendation for the use or protection of one generic name among synonymous names that may be either sexually or asexually typified. A table is presented that summarizes these recommendations. Among the genera most commonly encountered in this order, Cytospora is recommended over Valsa and Diaporthe over Phomopsis. New combinations are introduced for the oldest epithet of important species in the recommended genus. These include Amphiporthe tiliae, Coryneum lanciforme, Cytospora brevispora, C. ceratosperma, C. cinereostroma, C. eugeniae, C. fallax, C. myrtagena, Diaporthe amaranthophila, D. annonacearum, D. bougainvilleicola, D. caricae-papayae, D. cocoina, D. cucurbitae, D. juniperivora, D. leptostromiformis, D. pterophila, D. theae, D. vitimegaspora, Mastigosporella georgiana, Pilidiella angustispora, P. calamicola, P. pseudogranati, P. stromatica, and P. terminaliae.In advancing to one name for fungi, this paper treats generic names competing for use in the order Diaporthales (Ascomycota, Sordariomycetes) and makes a recommendation for the use or protection of one generic name among synonymous names that may be either sexually or asexually typified. A table is presented that summarizes these recommendations. Among the genera most commonly encountered in this order, Cytospora is recommended over Valsa and Diaporthe over Phomopsis. New combinations are introduced for the oldest epithet of important species in the recommended genus. These include Amphiporthe tiliae, Coryneum lanciforme, Cytospora brevispora, C. ceratosperma, C. cinereostroma, C. eugeniae, C. fallax, C. myrtagena, Diaporthe amaranthophila, D. annonacearum, D. bougainvilleicola, D. caricae-papayae, D. cocoina, D. cucurbitae, D. juniperivora, D. leptostromiformis, D. pterophila, D. theae, D. vitimegaspora, Mastigosporella georgiana, Pilidiella angustispora, P. calamicola, P. pseudogranati, P. stromatica, and P. terminaliae
Mycobacterium bovis in Panama, 2013
Full text linkPanama remains free of zoonotic tuberculosis caused by Mycobacterium bovis. However, DNA fingerprinting of 7 M. bovis isolates from a 2013 bovine tuberculosis outbreak indicated minimal homology with strains previously circulating in Panama. M. bovis dispersion into Panama highlights the need for enhanced genotype testing to track zoonotic infections.Panama remains free of zoonotic tuberculosis caused by Mycobacterium bovis. However, DNA fingerprinting of 7 M. bovis isolates from a 2013 bovine tuberculosis outbreak indicated minimal homology with strains previously circulating in Panama. M. bovis dispersion into Panama highlights the need for enhanced genotype testing to track zoonotic infections
Phytochemical composition, antiparasitic and α–glucosidase inhibition activities from Pelliciera rhizophorae
Full text linkPanama has an extensive mangrove area and it is one of the countries with the highest biodiversity in America. Mangroves are widely used in traditional medicine, nevertheless, there are very few studies that validates their medicinal properties in America. Given the urgent need for therapeutic options to treat several diseases of public health importance, mangrove ecosystem could be an interesting source of new bioactive molecules. This study was designed to evaluate the potential of Pelliciera rhizophorae as a source of bioactive compounds. Results: The present investigation was undertaken to explore the possible antiparasitic potential and α-glucosidase inhibition by compounds derived from the Panamanian mangrove Pelliciera rhizophorae. Bioassay-guided fractiona‑ tion of the crude extract led to the isolation of ten chemical compounds: α-amyrine (1), β-amyrine (2), ursolic acid (3), oleanolic acid (4), betulinic acid (5), brugierol (6) iso-brugierol (7), kaempferol (8), quercetin (9), and quercetrin (10). The structures of these compounds were established by spectroscopic analyses including APCI-HR-MS and NMR. Compounds 4 (IC50 = 5.3 µM), 8 (IC50 = 22.9 µM) and 10 (IC50 = 3.4 µM) showed selective antiparasitic activity against Leishmania donovani, while compounds 1 (IC50 = 19.0 µM) and 5 (IC50 = 18.0 µM) exhibited selectivity against Tripanosoma cruzi and Plasmodium falciparum, respectively. Moreover, compounds 1–5 inhibited α-glucosidase enzyme in a concentration-dependent manner with IC50 values of 1.45, 0.02, 1.08, 0.98 and 2.37 µM, respectively. Their inhibitory activity was higher than that of antidiabetic drug acarbose (IC50 217.7 µM), used as a positive control. Kinetic analysis established that the five compounds acted as competitive inhibitors. Docking analysis predicted that all triterpenes bind at the same site that acarbose in the human intestinal α-glucosidase (PDB: 3TOP).Panama has an extensive mangrove area and it is one of the countries with the highest biodiversity in America. Mangroves are widely used in traditional medicine, nevertheless, there are very few studies that validates their medicinal properties in America. Given the urgent need for therapeutic options to treat several diseases of public health importance, mangrove ecosystem could be an interesting source of new bioactive molecules. This study was designed to evaluate the potential of Pelliciera rhizophorae as a source of bioactive compounds. Results: The present investigation was undertaken to explore the possible antiparasitic potential and α-glucosidase inhibition by compounds derived from the Panamanian mangrove Pelliciera rhizophorae. Bioassay-guided fractiona‑ tion of the crude extract led to the isolation of ten chemical compounds: α-amyrine (1), β-amyrine (2), ursolic acid (3), oleanolic acid (4), betulinic acid (5), brugierol (6) iso-brugierol (7), kaempferol (8), quercetin (9), and quercetrin (10). The structures of these compounds were established by spectroscopic analyses including APCI-HR-MS and NMR. Compounds 4 (IC50 = 5.3 µM), 8 (IC50 = 22.9 µM) and 10 (IC50 = 3.4 µM) showed selective antiparasitic activity against Leishmania donovani, while compounds 1 (IC50 = 19.0 µM) and 5 (IC50 = 18.0 µM) exhibited selectivity against Tripanosoma cruzi and Plasmodium falciparum, respectively. Moreover, compounds 1–5 inhibited α-glucosidase enzyme in a concentration-dependent manner with IC50 values of 1.45, 0.02, 1.08, 0.98 and 2.37 µM, respectively. Their inhibitory activity was higher than that of antidiabetic drug acarbose (IC50 217.7 µM), used as a positive control. Kinetic analysis established that the five compounds acted as competitive inhibitors. Docking analysis predicted that all triterpenes bind at the same site that acarbose in the human intestinal α-glucosidase (PDB: 3TOP)
Genome-wide discovery and development of polymorphic microsatellites from Leishmania panamensis parasites circulating in central Panama
Full text linkThe parasite Leishmania panamensis is the main cause of leishmaniasis in Panama. The disease is largely uncontrolled, with a rising incidence and no appropriate control measures. While microsatellites are considered some of the best genetic markers to study population genetics and molecular epidemiology in these and other parasites, none has been developed for L. panamensisThe parasite Leishmania panamensis is the main cause of leishmaniasis in Panama. The disease is largely uncontrolled, with a rising incidence and no appropriate control measures. While microsatellites are considered some of the best genetic markers to study population genetics and molecular epidemiology in these and other parasites, none has been developed for L. panamensi
First report of Tomato leaf curl Sinaloa virus infecting tomato crops in Panama
Full text linkIn April 2011 and September 2012, virus-like symptoms were observed in open field- and greenhouse-grown tomato crops (Solanum lycopersicum) in Chiriquí, the westernmost province of Panama. Samples from symptombearing plants (127 in all) were collected and tested for the presence of begomoviruses by polymerase chain reaction (PCR) assays with sets of degenerated primers designed to amplify parts of the DNA-A and DNA-B components (Rojas et al., 1993; Table 1). Products of the expected sizes, obtained with both DNA-A- and DNA-B-specific primers for 49 samples, suggested infection with New World bipartite begomoviruses. This corresponds to an incidence of 26% (8 plants) in open field, and 43% (41 plants) in greenhouse crops. Primers specific for ten tomato-infecting begomoviruses found in Central America (Engel et al., 1998; Nakhla et al., 2005; Table 1) were used to typify the PCR-positive samples. This analysis revealed Potato yellow mosaic Panama virus (PYMPV) or Tomato leaf curl Sinaloa virus (ToLCSiV) in 44 (90%) or 40 (82%) of the samples, respectively. All contained at least one virus, the majority (i.e. 35) indeed both, with no indication of the other viruses tested. BLAST analysis of two PCR products' sequences of the distinct viruses (GenBank Accession Nos. KP313717 for PYMPV and KP318651 for ToLCSiV, respectively) revealed that KP313717 shared 99 % DNA sequence identity with PYMPV - [Panama:Divisa:Tomato:1996] (PYMPV-[PA:Div:Tom:96], (Y15034) (Engel et al., 1998), and KP318651 99 % identity with ToLCSiV - [Nicaragua:Santa Lucia] (ToLCSiV-[NI:SL], (AJ608286) (Rojas et al., 2005) and three other ToLCSiV sequences: [Nicaragua:Santa Lucia] (AJ508779), [Nicaragua:Sebaco] (AJ508780) (Rojas et al., 2005), and [Costa Rica:Alajuela] (AF131213); as well as 98 % identity with ToLCSiV-[Nicaragua:Condega] (AJ508778) (Rojas et al., 2005). Differences in symptom expression were in some cases observed between plants infected with both viruses (Fig. 1A), or with PYMPV (Fig. 1B) or ToLCSiV (Fig. 1C) alone. Begomovirus-free plants (Fig. 1D) also showed virus-like symptoms resembling those induced by other viruses, especially in the Potyviridae and Tobamoviridae (Polston & Anderson, 1997). Due to the high capacity of recombination between different begomoviruses (Davino et al., 2012), the existence or development of novel recombinant molecules cannot be excluded, which could lead to the emergence of new begomoviruses with different biological properties compared to the ancestral parental viruses in the future. To our knowledge, this is not only the first detection of ToLCSiV in Panama, but also the first report of PYMPV in Panama's western highlands, and the first ever report of PYMPV/ToLCSiV mixed infection. Additional studies on incidence and distribution of these viruses in Panama are in progress.In April 2011 and September 2012, virus-like symptoms were observed in open field- and greenhouse-grown tomato crops (Solanum lycopersicum) in Chiriquí, the westernmost province of Panama. Samples from symptombearing plants (127 in all) were collected and tested for the presence of begomoviruses by polymerase chain reaction (PCR) assays with sets of degenerated primers designed to amplify parts of the DNA-A and DNA-B components (Rojas et al., 1993; Table 1). Products of the expected sizes, obtained with both DNA-A- and DNA-B-specific primers for 49 samples, suggested infection with New World bipartite begomoviruses. This corresponds to an incidence of 26% (8 plants) in open field, and 43% (41 plants) in greenhouse crops. Primers specific for ten tomato-infecting begomoviruses found in Central America (Engel et al., 1998; Nakhla et al., 2005; Table 1) were used to typify the PCR-positive samples. This analysis revealed Potato yellow mosaic Panama virus (PYMPV) or Tomato leaf curl Sinaloa virus (ToLCSiV) in 44 (90%) or 40 (82%) of the samples, respectively. All contained at least one virus, the majority (i.e. 35) indeed both, with no indication of the other viruses tested. BLAST analysis of two PCR products' sequences of the distinct viruses (GenBank Accession Nos. KP313717 for PYMPV and KP318651 for ToLCSiV, respectively) revealed that KP313717 shared 99 % DNA sequence identity with PYMPV - [Panama:Divisa:Tomato:1996] (PYMPV-[PA:Div:Tom:96], (Y15034) (Engel et al., 1998), and KP318651 99 % identity with ToLCSiV - [Nicaragua:Santa Lucia] (ToLCSiV-[NI:SL], (AJ608286) (Rojas et al., 2005) and three other ToLCSiV sequences: [Nicaragua:Santa Lucia] (AJ508779), [Nicaragua:Sebaco] (AJ508780) (Rojas et al., 2005), and [Costa Rica:Alajuela] (AF131213); as well as 98 % identity with ToLCSiV-[Nicaragua:Condega] (AJ508778) (Rojas et al., 2005). Differences in symptom expression were in some cases observed between plants infected with both viruses (Fig. 1A), or with PYMPV (Fig. 1B) or ToLCSiV (Fig. 1C) alone. Begomovirus-free plants (Fig. 1D) also showed virus-like symptoms resembling those induced by other viruses, especially in the Potyviridae and Tobamoviridae (Polston & Anderson, 1997). Due to the high capacity of recombination between different begomoviruses (Davino et al., 2012), the existence or development of novel recombinant molecules cannot be excluded, which could lead to the emergence of new begomoviruses with different biological properties compared to the ancestral parental viruses in the future. To our knowledge, this is not only the first detection of ToLCSiV in Panama, but also the first report of PYMPV in Panama's western highlands, and the first ever report of PYMPV/ToLCSiV mixed infection. Additional studies on incidence and distribution of these viruses in Panama are in progress
Vacuolar Targeting of Cry1Ac and its Effects on Expression and Stability in Tobacco.
Full text linkIncreasing heterologous expression of delta endotoxins of Bacillus thuringiensis in transgenic plants is being actively pursued as a
means to increase their efficacy and to delay insect resistance. To examine if vacuoles could be used as alternate localization sites of delta endotoxins we developed binary vectors with a chimeric vacuole targeting signals and verified its localization efficiency by creating GFP fusions of Cry1Ac. Transgenic tobacco plants expressing Cry1Ac localized either to cytosol and vacuoles were generated and confirmed by PCR, QPCR and ELISA. Comparative protein expression analysis by quantitative ELISA showed that
maximum, percentage total soluble protein of Cry1Ac was 0.64 and 1% in cytosol and vacuole targeted plants, respectively. However, detailed protein expression analysis showed that there are no significant differences in expression of Cry1Ac between cytosol and vacuole targeted plants. These results were further corroborated by immunoblot analysis as well as insect bioassays. Nevertheless, our study demonstrated that delta endotoxins could be targeted to vacuoles and expressed successfully which is of importance when gene stacking is being pursed where alternate localization sites are employed for different genes.Increasing heterologous expression of delta endotoxins of Bacillus thuringiensis in transgenic plants is being actively pursued as a
means to increase their efficacy and to delay insect resistance. To examine if vacuoles could be used as alternate localization sites of delta endotoxins we developed binary vectors with a chimeric vacuole targeting signals and verified its localization efficiency by creating GFP fusions of Cry1Ac. Transgenic tobacco plants expressing Cry1Ac localized either to cytosol and vacuoles were generated and confirmed by PCR, QPCR and ELISA. Comparative protein expression analysis by quantitative ELISA showed that
maximum, percentage total soluble protein of Cry1Ac was 0.64 and 1% in cytosol and vacuole targeted plants, respectively. However, detailed protein expression analysis showed that there are no significant differences in expression of Cry1Ac between cytosol and vacuole targeted plants. These results were further corroborated by immunoblot analysis as well as insect bioassays. Nevertheless, our study demonstrated that delta endotoxins could be targeted to vacuoles and expressed successfully which is of importance when gene stacking is being pursed where alternate localization sites are employed for different genes
Microthyriaceae sp., an endophytic fungus
Full text linkIn screening for natural products with antiparasitic activity, an endophytic fungus, strain F2611, isolated from above-ground tissue of the tropical grass Paspalum conjugatum (Poaceae) in Panama, was chosen for bioactive principle elucidation. Cultivation on malt extract agar (MEA) followed by bioassayguided chromatographic fractionation of the extract led to the isolation of the new polyketide integrasone B (1) and two known mycotoxins, sterigmatocystin (2) and secosterigmatocystin (3). Sterigmatocystin (2) was found to be the main antiparasitic compound in the fermentation extract of this fungus, possessing potent and selective antiparasitic activity against Trypanosoma cruzi, the cause of Chagas disease, with an IC50 value of 0 13 lmol l 1. Compounds 2 and 3 showed high cytotoxicity against Vero cells (IC50 of 0 06 and 0 97 lmol l 1, respectively). The new natural product integrasone B (1), which was co-purified from the active fractions, constitutes the second report of a natural product possessing an epoxyquinone with a lactone ring and exhibited no significant biological activity. Strain F2611 represents a previously undescribed taxon within the Microthyriaceae (Dothideomycetes, AscomycotaIn screening for natural products with antiparasitic activity, an endophytic fungus, strain F2611, isolated from above-ground tissue of the tropical grass Paspalum conjugatum (Poaceae) in Panama, was chosen for bioactive principle elucidation. Cultivation on malt extract agar (MEA) followed by bioassayguided chromatographic fractionation of the extract led to the isolation of the new polyketide integrasone B (1) and two known mycotoxins, sterigmatocystin (2) and secosterigmatocystin (3). Sterigmatocystin (2) was found to be the main antiparasitic compound in the fermentation extract of this fungus, possessing potent and selective antiparasitic activity against Trypanosoma cruzi, the cause of Chagas disease, with an IC50 value of 0 13 lmol l 1. Compounds 2 and 3 showed high cytotoxicity against Vero cells (IC50 of 0 06 and 0 97 lmol l 1, respectively). The new natural product integrasone B (1), which was co-purified from the active fractions, constitutes the second report of a natural product possessing an epoxyquinone with a lactone ring and exhibited no significant biological activity. Strain F2611 represents a previously undescribed taxon within the Microthyriaceae (Dothideomycetes, AscomycotaLaboratory of Tropical Bioorganic Chemistry, Faculty of Natural Exact Sciences and Technology, University of Panama, Panama City, Republic of Panama
Smithsonian Tropical Research Institute, Balboa, Panama City, Republic of Panama
Centro de Biodiversidade, Gen omica Integrativa e Funcional (BioFIG), Universidade de Lisboa, Faculdade de Ci^encias, Edif ıcio ICAT/TecLabs, Campus da FCUL, Campo Grande, Lisboa, Portugal
Institute for Advanced Scientific Investigation and High Technology Services, National Secretariat of Science, Technology, and Innovation, City of Knowledge, Panama City, Republic of Panama
School of Plant Sciences, The University of Arizona, Tucson, AZ, USA
Department of Biology, University of Utah, Salt Lake City, UT, USA
Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, US
Revisiting Metal Toxicity in Neurodegenerative Diseases and Stroke: Therapeutic Potential
Full text linkExcessive accumulation of pro-oxidant metals, observed in affected brain regions, has consistently been implicated as a contributor to the brain pathology including neurodegenerative diseases and acute injuries such as stroke. Furthermore, the potential interactions between metal toxicity and other commonly associated etiological factors, such as misfolding/aggregation of amyloidogenic proteins or genomic damage, are poorly understood. Decades of research provide compelling evidence implicating metal overload in neurological diseases and stroke. However, the utility of metal toxicity as a therapeutic target is controversial, possibly due to a lack of comprehensive understanding of metal dyshomeostasismediated neuronal pathology. In this article, we discuss the current understanding of metal toxicity and the challenges associated with metal-targeted therapies.Excessive accumulation of pro-oxidant metals, observed in affected brain regions, has consistently been implicated as a contributor to the brain pathology including neurodegenerative diseases and acute injuries such as stroke. Furthermore, the potential interactions between metal toxicity and other commonly associated etiological factors, such as misfolding/aggregation of amyloidogenic proteins or genomic damage, are poorly understood. Decades of research provide compelling evidence implicating metal overload in neurological diseases and stroke. However, the utility of metal toxicity as a therapeutic target is controversial, possibly due to a lack of comprehensive understanding of metal dyshomeostasismediated neuronal pathology. In this article, we discuss the current understanding of metal toxicity and the challenges associated with metal-targeted therapies
Anti-malarial activity and HS-SPME-GC-MS chemical profiling of Plinia cerrocampanensis leaf essential oil
Full text linkPlinia cerrocampanensis is an endemic plant of Panama. The leaf essential oil of this plant has shown antibacterial activity. However, anti-malarial activity and chemical profiling by HS-SPME-GC-MS of this essential oil have not been reported before. Anti-malarial activity of the essential oil (EO) was evaluated in vitro against chloroquine-sensitive HB3 and chloroquine-resistant W2 strains of Plasmodium falciparum. Synergistic effect of chloroquine and the EO on parasite growth was evaluated by calculating the combination index. A methodology involving headspace solid phase microextraction and gas chromatography-mPlinia cerrocampanensis is an endemic plant of Panama. The leaf essential oil of this plant has shown antibacterial activity. However, anti-malarial activity and chemical profiling by HS-SPME-GC-MS of this essential oil have not been reported before. Anti-malarial activity of the essential oil (EO) was evaluated in vitro against chloroquine-sensitive HB3 and chloroquine-resistant W2 strains of Plasmodium falciparum. Synergistic effect of chloroquine and the EO on parasite growth was evaluated by calculating the combination index. A methodology involving headspace solid phase microextraction and gas chromatography-
Pervasive effects of a dominant foliar endophytic fungus on host genetic and phenotypic expression in a tropical tree
Full text linkIt is increasingly recognized that macro-organisms (corals, insects, plants, vertebrates) consist of both host tissues and multiple microbial symbionts that play essential roles in their host’s ecological and evolutionary success. Consequently, identifying benefits and costs of symbioses, as well as mechanisms underlying them are research priorities. All plants surveyed under natural conditions harbor foliar endophytic fungi (FEF) in their leaf tissues, often at high densities. Despite producing no visible effects on their hosts, experiments have nonetheless shown that FEF reduce pathogen and herbivore damage. Here, combining results from three genomic, and two physiological experiments, we demonstrate pervasive genetic and phenotypic effects of the apparently asymptomatic endophytes on their hosts. Specifically, inoculation of endophyte-free (E−) Theobroma cacao leaves with Colletotrichum tropicale (E+), the dominant FEF species in healthy T. cacao, induces consistent changes in the expression of hundreds of host genes, including many with known defensive functions. Further, E+ plants exhibited increased lignin and cellulose content, reduced maximum rates of photosynthesis (Amax), and enrichment of nitrogen-15 and carbon-13 isotopes. These phenotypic changes observed in E+ plants correspond to changes in expression of specific functional genes in related pathways. Moreover, a cacao gene (Tc00g04254) highly up-regulated by C. tropicale also confers resistance to pathogen damage in the absence of endophytes or their products in host tissues. Thus, the benefits of increased pathogen resistance in E+ plants are derived in part from up-regulation of intrinsic host defense responses, and appear to be offset by potential costs including reduced photosynthesis, altered host nitrogen metabolism, and endophyte heterotrophy of host tissues. Similar effects are likely in most plant-endophyte interactions, and should be recognized in the design and interpretation of genetic and phenotypic studies of plantsIt is increasingly recognized that macro-organisms (corals, insects, plants, vertebrates) consist of both host tissues and multiple microbial symbionts that play essential roles in their host’s ecological and evolutionary success. Consequently, identifying benefits and costs of symbioses, as well as mechanisms underlying them are research priorities. All plants surveyed under natural conditions harbor foliar endophytic fungi (FEF) in their leaf tissues, often at high densities. Despite producing no visible effects on their hosts, experiments have nonetheless shown that FEF reduce pathogen and herbivore damage. Here, combining results from three genomic, and two physiological experiments, we demonstrate pervasive genetic and phenotypic effects of the apparently asymptomatic endophytes on their hosts. Specifically, inoculation of endophyte-free (E−) Theobroma cacao leaves with Colletotrichum tropicale (E+), the dominant FEF species in healthy T. cacao, induces consistent changes in the expression of hundreds of host genes, including many with known defensive functions. Further, E+ plants exhibited increased lignin and cellulose content, reduced maximum rates of photosynthesis (Amax), and enrichment of nitrogen-15 and carbon-13 isotopes. These phenotypic changes observed in E+ plants correspond to changes in expression of specific functional genes in related pathways. Moreover, a cacao gene (Tc00g04254) highly up-regulated by C. tropicale also confers resistance to pathogen damage in the absence of endophytes or their products in host tissues. Thus, the benefits of increased pathogen resistance in E+ plants are derived in part from up-regulation of intrinsic host defense responses, and appear to be offset by potential costs including reduced photosynthesis, altered host nitrogen metabolism, and endophyte heterotrophy of host tissues. Similar effects are likely in most plant-endophyte interactions, and should be recognized in the design and interpretation of genetic and phenotypic studies of plant