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Massimo NC, Nandi Devan MM, Arendt KR, Wilch MH, Riddle JM, Furr SH, Steen C, U'Ren JM, Sandberg DC, Arnold AE. Fungal endophytes in aboveground tissues of desert plants: infrequent in culture, but highly diverse and distinctive symbionts. MICROBIAL ECOLOGY 2015; 70:61-76. [PMID: 25645243 PMCID: PMC4457668 DOI: 10.1007/s00248-014-0563-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 12/26/2014] [Indexed: 05/02/2023]
Abstract
In hot deserts, plants cope with aridity, high temperatures, and nutrient-poor soils with morphological and biochemical adaptations that encompass intimate microbial symbioses. Whereas the root microbiomes of arid-land plants have received increasing attention, factors influencing assemblages of symbionts in aboveground tissues have not been evaluated for many woody plants that flourish in desert environments. We evaluated the diversity, host affiliations, and distributions of endophytic fungi associated with photosynthetic tissues of desert trees and shrubs, focusing on nonsucculent woody plants in the species-rich Sonoran Desert. To inform our strength of inference, we evaluated the effects of two different nutrient media, incubation temperatures, and collection seasons on the apparent structure of endophyte assemblages. Analysis of >22,000 tissue segments revealed that endophytes were isolated four times more frequently from photosynthetic stems than leaves. Isolation frequency was lower than expected given the latitude of the study region and varied among species a function of sampling site and abiotic factors. However, endophytes were very species-rich and phylogenetically diverse, consistent with less arid sites of a similar latitudinal position. Community composition differed among host species, but not as a function of tissue type, sampling site, sampling month, or exposure. Estimates of abundance, diversity, and composition were not influenced by isolation medium or incubation temperature. Phylogenetic analyses of the most commonly isolated genus (Preussia) revealed multiple evolutionary origins of desert-plant endophytism and little phylogenetic structure with regard to seasonality, tissue preference, or optimal temperatures and nutrients for growth in vitro. Together, these results provide insight into endophytic symbioses in desert-plant communities and can be used to optimize strategies for capturing endophyte biodiversity at regional scales.
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Affiliation(s)
- Nicholas C Massimo
- School of Plant Sciences, The University of Arizona, 1140 E. South Campus Drive, Forbes 303, Tucson, AZ, 85721, USA
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Tantirungkij M, Nasanit R, Limtong S. Assessment of endophytic yeast diversity in rice leaves by a culture-independent approach. Antonie van Leeuwenhoek 2015; 108:633-47. [DOI: 10.1007/s10482-015-0519-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 06/23/2015] [Indexed: 10/23/2022]
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Campos FF, Sales Junior PA, Romanha AJ, Araújo MSS, Siqueira EP, Resende JM, Alves TMA, Martins-Filho OA, Santos VLD, Rosa CA, Zani CL, Cota BB. Bioactive endophytic fungi isolated from Caesalpinia echinata Lam. (Brazilwood) and identification of beauvericin as a trypanocidal metabolite from Fusarium sp. Mem Inst Oswaldo Cruz 2015; 110:65-74. [PMID: 25742265 PMCID: PMC4371219 DOI: 10.1590/0074-02760140243] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/28/2014] [Indexed: 12/20/2022] Open
Abstract
Aiming to identify new sources of bioactive secondary metabolites, we isolated 82
endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia
echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro
assays. The organic extracts from three isolates showed antibacterial activity
against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration
(MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC
64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL),
Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a
concentration of 20 μg/mL showed antitumour activities against human breast cancer
and human renal cancer cells, while two isolates showed anti-tumour activities
against human melanoma cancer cells. Six extracts were able to reduce the
proliferation of human peripheral blood mononuclear cells, indicating some degree of
selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania)
amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL.
The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected
to bioguided fractionation, which revealed beauvericin as the compound responsible
for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a
half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular
culture assay.
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Affiliation(s)
- Fernanda Fraga Campos
- Departamento de Ciências Biológicas e da Saúde, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, MG, Brasil
| | | | | | | | | | | | - Tânia M A Alves
- Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil
| | | | - Vera Lúcia dos Santos
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - Carlos A Rosa
- Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil
| | - Carlos L Zani
- Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil
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Martin R, Gazis R, Skaltsas D, Chaverri P, Hibbett D. Unexpected diversity of basidiomycetous endophytes in sapwood and leaves of Hevea. Mycologia 2015; 107:284-97. [PMID: 25572095 DOI: 10.3852/14-206] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Research on fungal endophytes has expanded dramatically in recent years, but little is known about the diversity and ecological roles of endophytic basidiomycetes. Here we report the analysis of 310 basidiomycetous endophytes isolated from wild and planted populations of the rubber tree genus, Hevea. Species accumulation curves were nonasymptotic, as in the majority of endophyte surveys, indicating that more sampling is needed to recover the true diversity of the community. One hundred eighteen OTUs were delimited, representing nine orders of Basidiomycota (Agaricales, Atheliales, Auriculariales, Cantharellales, Hymenochaetales, Polyporales, Russulales, Septobasidiales, Tremellales). The diversity of basidiomycetous endophytes found inhabiting wild populations of Hevea was comparable to that present in plantations. However, when samples were segregated by tissue type, sapwood of wild populations was found to contain a higher number of species than sapwood of planted trees. Seventy-five percent of isolates were members of the Polyporales, the majority in the phlebioid clade. Most of the species belong to clades known to cause a white-rot type of wood decay. Two species in the insect-associated genus Septobasidium were isolated. The most frequently isolated genera included Bjerkandera, Ceriporia, Phanerochaete, Phlebia, Rigidoporus, Tinctoporellus, Trametes (Polyporales), Peniophora, Stereum (Russulales) and Coprinellus (Agaricales), all of which have been reported as endophytes from a variety of hosts, across wide geographic locations. Literature records on the geographic distribution and host association of these genera revealed that their distribution and substrate affinity could be extended if the endophytic niche was investigated as part of fungal biodiversity surveys.
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Affiliation(s)
- Rachael Martin
- Clark University, Biology Department, 950 Main Street, Worcester, Massachusetts 01610
| | - Romina Gazis
- Clark University, Biology Department, 950 Main Street, Worcester, Massachusetts 01610
| | - Demetra Skaltsas
- University of Maryland, Department of Plant Science and Landscape Architecture, 2112 Plant Sciences Building, College Park, Maryland 20742
| | - Priscila Chaverri
- University of Maryland, Department of Plant Science and Landscape Architecture, 2112 Plant Sciences Building, College Park, Maryland 20742, and Universidad de Costa Rica, Escuela de Biología, Apdo. 11501-2060, San Pedro, San José, Costa Rica
| | - David Hibbett
- Clark University, Biology Department, 950 Main Street, Worcester, Massachusetts 01610
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Mejía LC, Herre EA, Sparks JP, Winter K, García MN, Van Bael SA, Stitt J, Shi Z, Zhang Y, Guiltinan MJ, Maximova SN. Pervasive effects of a dominant foliar endophytic fungus on host genetic and phenotypic expression in a tropical tree. Front Microbiol 2014; 5:479. [PMID: 25309519 PMCID: PMC4162356 DOI: 10.3389/fmicb.2014.00479] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 08/25/2014] [Indexed: 12/05/2022] Open
Abstract
It 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 plants.
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Affiliation(s)
- Luis C Mejía
- Smithsonian Tropical Research Institute Unit 9100, USA ; Department of Plant Science and The Huck Institutes of the Life Sciences, The Pennsylvania State University University Park, PA, USA
| | | | - Jed P Sparks
- Department of Ecology and Evolution, Cornell University Ithaca, NY, USA
| | - Klaus Winter
- Smithsonian Tropical Research Institute Unit 9100, USA
| | | | - Sunshine A Van Bael
- Smithsonian Tropical Research Institute Unit 9100, USA ; Department of Ecology and Evolutionary Biology, Tulane University New Orleans, LA, USA
| | - Joseph Stitt
- Social, Life and Engineering Sciences Imaging Center, Materials Research Institute University Park, PA, USA
| | - Zi Shi
- Department of Plant Science and The Huck Institutes of the Life Sciences, The Pennsylvania State University University Park, PA, USA
| | - Yufan Zhang
- Department of Plant Science and The Huck Institutes of the Life Sciences, The Pennsylvania State University University Park, PA, USA
| | - Mark J Guiltinan
- Department of Plant Science and The Huck Institutes of the Life Sciences, The Pennsylvania State University University Park, PA, USA
| | - Siela N Maximova
- Department of Plant Science and The Huck Institutes of the Life Sciences, The Pennsylvania State University University Park, PA, USA
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The Colletotrichum gigasporum species complex. Persoonia - Molecular Phylogeny and Evolution of Fungi 2014; 33:83-97. [PMID: 25737595 PMCID: PMC4312939 DOI: 10.3767/003158514x684447] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 03/06/2014] [Indexed: 11/25/2022]
Abstract
In a preliminary analysis, 21 Colletotrichum strains with large conidia preserved in the CBS culture collection clustered with a recently described species, C. gigasporum, forming a clade distinct from other currently known Colletotrichum species complexes. Multi-locus phylogenetic analyses (ITS, ACT, TUB2, CHS-1, GAPDH) as well as each of the single-locus analyses resolved seven distinct species, one of them being C. gigasporum. Colletotrichum gigasporum and its close allies thus constitute a previously unknown species complex with shared morphological features. Five of the seven species accepted in the C. gigasporum species complex are described here as novel species, namely C. arxii, C. magnisporum, C. pseudomajus, C. radicis and C. vietnamense. A species represented by a single sterile strain, namely CBS 159.50, was not described as novel species, and is treated as Colletotrichum sp. CBS 159.50. Furthermore, C. thailandicum is reduced to synonymy with C. gigasporum.
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Khan AL, Waqas M, Kang SM, Al-Harrasi A, Hussain J, Al-Rawahi A, Al-Khiziri S, Ullah I, Ali L, Jung HY, Lee IJ. Bacterial endophyte Sphingomonas sp. LK11 produces gibberellins and IAA and promotes tomato plant growth. J Microbiol 2014; 52:689-95. [PMID: 24994010 DOI: 10.1007/s12275-014-4002-7] [Citation(s) in RCA: 191] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 05/12/2014] [Accepted: 05/14/2014] [Indexed: 11/27/2022]
Abstract
Plant growth promoting endophytic bacteria have been identified as potential growth regulators of crops. Endophytic bacterium, Sphingomonas sp. LK11, was isolated from the leaves of Tephrosia apollinea. The pure culture of Sphingomonas sp. LK11 was subjected to advance chromatographic and spectroscopic techniques to extract and isolate gibberellins (GAs). Deuterated standards of [17, 17-(2)H2]-GA4, [17, 17-(2)H2]-GA9 and [17, 17-(2)H2]-GA20 were used to quantify the bacterial GAs. The analysis of the culture broth of Sphingomonas sp. LK11 revealed the existence of physiologically active gibberellins (GA4: 2.97 ± 0.11 ng/ml) and inactive GA9 (0.98 ± 0.15 ng/ml) and GA20 (2.41 ± 0.23). The endophyte also produced indole acetic acid (11.23 ± 0.93 μM/ml). Tomato plants inoculated with endophytic Sphingomonas sp. LK11 showed significantly increased growth attributes (shoot length, chlorophyll contents, shoot, and root dry weights) compared to the control. This indicated that such phyto-hormones-producing strains could help in increasing crop growth.
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Affiliation(s)
- Abdul Latif Khan
- Department of Biological Sciences and Chemistry, University of Nizwa, Nizwa, Oman
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58
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Almeida C, Ortega H, Higginbotham S, Spadafora C, Arnold A, Coley P, Kursar T, Gerwick W, Cubilla-Rios L. Chemical and bioactive natural products from Microthyriaceae sp., an endophytic fungus from a tropical grass. Lett Appl Microbiol 2014; 59:58-64. [DOI: 10.1111/lam.12245] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 02/21/2014] [Accepted: 03/04/2014] [Indexed: 11/28/2022]
Affiliation(s)
- C. Almeida
- Laboratory 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; Genómica Integrativa e Funcional (BioFIG); Universidade de Lisboa; Faculdade de Ciências; Edifício ICAT/TecLabs; Campus da FCUL; Campo Grande; Lisboa Portugal
| | - H. Ortega
- Laboratory 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
| | - S. Higginbotham
- Smithsonian Tropical Research Institute; Balboa Panama City Republic of Panama
| | - C. Spadafora
- Institute for Advanced Scientific Investigation and High Technology Services; National Secretariat of Science; Technology, and Innovation; City of Knowledge; Panama City Republic of Panama
| | - A.E. Arnold
- School of Plant Sciences; The University of Arizona; Tucson AZ USA
| | - P.D. Coley
- Smithsonian Tropical Research Institute; Balboa Panama City Republic of Panama
- Department of Biology; University of Utah; Salt Lake City UT USA
| | - T.A. Kursar
- Smithsonian Tropical Research Institute; Balboa Panama City Republic of Panama
- Department of Biology; University of Utah; Salt Lake City UT USA
| | - W.H. Gerwick
- 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 USA
| | - L. Cubilla-Rios
- Laboratory 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
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Chujo T, Scott B. Histone H3K9 and H3K27 methylation regulates fungal alkaloid biosynthesis in a fungal endophyte-plant symbiosis. Mol Microbiol 2014; 92:413-34. [PMID: 24571357 DOI: 10.1111/mmi.12567] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2014] [Indexed: 12/17/2022]
Abstract
Epichloё festucae is a filamentous fungus that forms a mutually beneficial symbiotic association with Lolium perenne. This endophyte synthesizes bioprotective lolitrems (ltm) and ergot alkaloids (eas) in planta but the mechanisms regulating expression of the corresponding subtelomeric gene clusters are not known. We show here that the status of histone H3 lysine 9 and lysine 27 trimethylation (H3K9me3/H3K27me3) at these alkaloid gene loci are critical determinants of transcriptional activity. Using ChIP-qPCR we found that levels of H3K9me3 and H3K27me3 were reduced at these loci in plant infected tissue compared to axenic culture. Deletion of E. festucae genes encoding the H3K9- (ClrD) or H3K27- (EzhB) methyltransferases led to derepression of ltm and eas gene expression under non-symbiotic culture conditions and a further enhancement of expression in the double deletion mutant. These changes in gene expression were matched by corresponding reductions in H3K9me3 and H3K27me3 marks. Both methyltransferases are also important for the symbiotic interaction between E. festucae and L. perenne. Our results show that the state of H3K9 and H3K27 trimethylation of E. festucae chromatin is an important regulatory layer controlling symbiosis-specific expression of alkaloid bioprotective metabolites and the ability of this symbiont to form a mutualistic interaction with its host.
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Affiliation(s)
- Tetsuya Chujo
- Institute of Fundamental Sciences, Massey University, Private Bag 11 222, Palmerston North, 4442, New Zealand
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60
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Higginbotham S, Wong WR, Linington RG, Spadafora C, Iturrado L, Arnold AE. Sloth hair as a novel source of fungi with potent anti-parasitic, anti-cancer and anti-bacterial bioactivity. PLoS One 2014; 9:e84549. [PMID: 24454729 PMCID: PMC3893167 DOI: 10.1371/journal.pone.0084549] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 11/15/2013] [Indexed: 01/30/2023] Open
Abstract
The extraordinary biological diversity of tropical forests harbors a rich chemical diversity with enormous potential as a source of novel bioactive compounds. Of particular interest are new environments for microbial discovery. Sloths – arboreal mammals commonly found in the lowland forests of Panama – carry a wide variety of micro- and macro-organisms on their coarse outer hair. Here we report for the first time the isolation of diverse and bioactive strains of fungi from sloth hair, and their taxonomic placement. Eighty-four isolates of fungi were obtained in culture from the surface of hair that was collected from living three-toed sloths (Bradypus variegatus, Bradypodidae) in Soberanía National Park, Republic of Panama. Phylogenetic analyses revealed a diverse group of Ascomycota belonging to 28 distinct operational taxonomic units (OTUs), several of which are divergent from previously known taxa. Seventy-four isolates were cultivated in liquid broth and crude extracts were tested for bioactivity in vitro. We found a broad range of activities against strains of the parasites that cause malaria (Plasmodium falciparum) and Chagas disease (Trypanosoma cruzi), and against the human breast cancer cell line MCF-7. Fifty fungal extracts were tested for antibacterial activity in a new antibiotic profile screen called BioMAP; of these, 20 were active against at least one bacterial strain, and one had an unusual pattern of bioactivity against Gram-negative bacteria that suggests a potentially new mode of action. Together our results reveal the importance of exploring novel environments for bioactive fungi, and demonstrate for the first time the taxonomic composition and bioactivity of fungi from sloth hair.
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Affiliation(s)
- Sarah Higginbotham
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
- * E-mail:
| | - Weng Ruh Wong
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Roger G. Linington
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Carmenza Spadafora
- Instituto de Investigaciones Científicas y Servicios de Alta Tecnología, Panama, Republic of Panama
| | - Liliana Iturrado
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
| | - A. Elizabeth Arnold
- School of Plant Sciences, University of Arizona, Tucson, Arizona, United States of America
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