Repositorio Digital Ikiam (Univ. Regional Amazónica)
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“Caracterización y potencial biorremediador de bacterias aisladas de asfalto proveniente de la Cantera de Pungarayacu en la Provincia de Napo, Ecuador
No full textLa Cantera del Pungarayacu, ubicada en la provincia de Napo-Ecuador, es uno de los
reservorios más grandes de crudo extrapesado de la región Amazónica. El crudo encontrado
es de los más recalcitrantes y difíciles de biodegradar debido a su baja biodisponibilidad. La
naturaleza de este sustrato, así como las condiciones físico-químicas del sitio, hacen de esta
zona el lugar idóneo para aislar y caracterizar bacterias con potenciales aplicaciones
biotecnológicas. En este estudio se aislaron tres cepas bacterianas asociadas al asfalto
proveniente de la Cantera del Pungarayacu, identificadas molecularmente como Serratia
marcescens subsp. marcescens, Cedecea lapagei y Serratia marcescens subsp. sakuensis. Sus
potenciales aplicaciones biotecnológicas fueron estudiadas mediante un análisis in silico. S.
marcescens subsp. marcescens es capaz de sintetizar el biosurfactante Serrawettin W1, que
podría ser empleado para incrementar la biodisponibilidad del crudo extrapesado presente en
la cantera, aumentando su taza de biodegradación. Dicho biosurfactante es sintetizado
mediante la actividad catalítica de una NRPS denominada SwrW. C. lapagei posee una oxidasa
multicobre con potencial aplicación en la biodegradación de masa lignocelulósica. S.
marcescens subsp. sakuensis tiene la capacidad de producir un pigmento rojizo llamado
prodigiosina, el cual posee actividad proapoptótica hacia líneas celulares cancerosas con poca
o nula toxicidad hacia células normales. Este trabajo busca establecer una línea base para el
estudio de potenciales biocatalizadores que puedan ser empleados en nuevas estrategias de
biorremediación de zonas contaminados con crudo altamente recalcitrante, así como el
estudio de otras aplicaciones biotecnológicas desde la Amazonía ecuatoriana
Brazilian Flora 2020: Leveraging the power of a collaborative scientific network
Get PDFand fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cy-bertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paperpresents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found inone of the world’s most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020.Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country.The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups exceptgymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distrib-uted, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of“scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first onlineFlora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil.This project also made all the information freely available online,providing a firm foundation for future research and for the management,conservation, and sustainable use of the Brazilian funga and flora
Inducción de la embriogénesis somática en Theobroma bicolor Humb. & Bonpl. cultivado en la Región Amazónica del Ecuador
Get PDFTheobroma bicolor Humb. & Bonpl. es una especie nativa de la Región Amazónica,
cuyas semillas se consumen tostadas y los frutos se utilizan en bebidas tradicionales. La
propagación de la especie a través de semillas está limitada por su condición alógama. La
embriogénesis somática (ES) es una herramienta poderosa para la propagación clonal, la cual
depende de reguladores de crecimiento (PGRs) como el ácido 2,4-diclorofenoxiacético (2,4-D),
cinetina (KIN) y tidiazuron (TDZ). El objetivo del presente trabajo fue el de explorar el efecto
de diferentes concentraciones de 2,4-D y TDZ en el proceso de inducción de la ES en T. bicolor.
Estaminodios fueron cultivados en medios suplementados con 9 o 20 µM de 2,4-D y 22.7 nM
o 1 µM de TDZ, seguido de un medio de cultivo suplementado con 9 µM de 2,4-D y 1.4 µM de
KIN y finalmente, en un medio de cultivo libre de PGRs. Las diferentes concentraciones de 2,4-
D y TDZ desencadenaron la vía embriogénica indirecta, iniciándose la formación del callo a los
8 días. En el medio de cultivo suplementado con 9 µM de 2,4-D y 22.7 nM de TDZ, se observó
90% de respuesta callogénica y 1.67% de embriogénica. Mientras que en el medio de cultivo
suplementado con 20 µM de 2,4-D y 1 µM de TDZ, la respuesta callogénica fue de 80% y la
embriogénica de 0%. Callos con potencial embriogénico están asociados a colores amarillo blanco-café y texturas acuosa-cerosa-friable. Los resultados observados muestran que la
capacidad embriogénica está asociada a las concentraciones de los PGRs
THE ECO NOMIC SUSTAINABILITY OF INVESTMENT IN RENEWABLE ENERGY SECTOR OF SANCTI SPIRITUS, CUBA
Get PDFEl presente estudio muestra resultados obtenidos durante el desarrollo de la investigación doctoral del primer autor, cuyo
objetivo es evaluar la Sostenibilidad Económica del proyecto de inversión energético renovable. Presenta dos secciones
fundamentales: Primero, se analizan críticamente las principales tendencias teórico – metodológicas de las fuentes especializadas; segundo, se ilustran los resultados obtenidos del diagnóstico realizado en el sector energético renovable de
la provincia Sancti Spíritus, Cuba. La evidencia teórica fundamental sugiere un carácter heterogéneo en las herramientas
propuestas por la comunidad especializada, siendo insuficientes desde la óptica económico – financiera; en cuanto a la
evidencia práctica fundamental, se aprecia un empleo mínimo de las mismas en el territorio espirituano, extensivo a todo el
territorio nacional. Los métodos empleados combinan la revisión documental, las opiniones críticas de los autores, la recopilación de datos de campo (de estudios de factibilidad fundamentalmente) y la aplicación de una encuesta al capital humano
de las entidades más representativa
Host relatedness and landscape connectivity shape pathogen spread in the puma, a large secretive carnivore
Get PDFUrban expansion can fundamentally alter wildlife movement and geneflow, but how urba-nization alters pathogen spread is poorly understood. Here, we combine high resolution hostand viral genomic data with landscape variables to examine the context of viral spread inpuma (Pumaconcolor) from two contrasting regions: one bounded by the wildland urbaninterface (WUI) and one unbounded with minimal anthropogenic development (UB). Wefound landscape variables and host geneflow explained significant amounts of variation offeline immunodeficiency virus (FIV) spread in the WUI, but not in the unbounded region. Themost important predictors of viral spread also differed; host spatial proximity, host related-ness, and mountain ranges played a role in FIV spread in the WUI, whereas roads might havefacilitated viral spread in the unbounded region. Our research demonstrates how anthro-pogenic landscapes can alter pathogen spread, providing a more nuanced understanding ofhost-pathogen relationships to inform disease ecology in free-ranging specie
Comparative Analysis of NADPH-Cytochrome P450 Reductases From Legumes for Heterologous Production of Triterpenoids in Transgenic Saccharomyces cerevisiae
Get PDFTriterpenoids are plant specialized metabolites with various pharmacological activities. They are widely distributed in higher plants, such as legumes. Because of their low accumulation in plants, there is a need for improving triterpenoid production. Cytochrome P450 monooxygenases (CYPs) play critical roles in the structural diversification of triterpenoids. To perform site-specific oxidations, CYPs require the electrons that are transferred by NADPH-cytochrome P450 reductase (CPR). Plants possess two main CPR classes, class I and class II. CPR classes I and II have been reported to be responsible for primary and specialized (secondary) metabolism, respectively. In this study, we first analyzed the CPR expression level of three legumes species, Medicago truncatula, Lotus japonicus, and Glycyrrhiza uralensis, showing that the expression level of CPR class I was lower and more stable, while that of CPR class II was higher in almost all the samples. We then co-expressed different combinations of CYP716As and CYP72As with different CPR classes from these three legumes in transgenic yeast. We found that CYP716As worked better with CPR-I from the same species, while CYP72As worked better with any CPR-IIs. Using engineered yeast strains, CYP88D6 paired with class II GuCPR produced the highest level of 11-oxo-β-amyrin, the important precursor of high-value metabolites glycyrrhizin. This study provides insight into co-expressing genes from legumes for heterologous production of triterpenoids in yeast
Taking the pulse of Earth’s tropical forests using networks of highly distributed plots
Get PDFTropical forests are the most diverse and productive ecosystems on Earth. While better understanding of these forests is critical for our collective future, until quite recently efforts to measure and monitor them have been largely disconnected. Networking is essential to discover the answers to questions that transcend borders and the horizons of funding agencies. Here we show how a global community is responding to the challenges of tropical ecosystem research with diverse teams measuring forests tree-by-tree in thousands of long-term plots. We review the major scientific discoveries of this work and show how this process is changing tropical forest science. Our core approach involves linking long-term grassroots initiatives with standardized protocols and data management to generate robust scaled-up results. By connecting tropical researchers and elevating their status, our Social Research Network model recognises the key role of the data originator in scientific discovery. Conceived in 1999 with RAINFOR (South America), our permanent plot networks have been adapted to Africa (AfriTRON) and Southeast Asia (T-FORCES) and widely emulated worldwide. Now these multiple initiatives are integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. Collectively these are transforming understanding of tropical forests and their biospheric role. Together we have discovered how, where and why forest carbon and biodiversity are responding to climate change, and how they feedback on it. This long-term pan-tropical collaboration has revealed a large long-term carbon sink and its trends, as well as making clear which drivers are most important, which forest processes are affected, where they are changing, what the lags are, and the likely future responses of tropical forests as the climate continues to change. By leveraging a remarkably old technology, plot networks are sparking a very modern revolution in tropical forest science. In the future, humanity can benefit greatly by nurturing the grassroots communities now collectively capable of generating unique, long-term understanding of Earth’s most precious forests
Report of the Special-purpose Committee on Virtual Participation in the Nomenclature Section
Get PDFThe Special-purpose Committee on Virtual Participation in the Nomenclature Section was established by the XIX International Botanical Congress (IBC) in Shenzhen, China in 2017, with the mandate "to investigate the possibility of and mechanisms for virtual participation and voting in the Nomenclature Section of an International Botanical Congress via the internet" and to report to the XX IBC. The wide access to the World Wide Web and availability of software for virtual meetings makes the possibility for virtual (online) attendance and voting at a Nomenclature Section seem attainable and advisable. In order to make informed recommendations, we discussed various aspects of online attendance and voting, such as: who should be able to observe?; what would qualify a person to cast institutional votes and personal votes?; if the accumulation of institutional votes should be allowed by an online voter; registration of online voters; how costs would be covered; and recommendations for online attendees. This report provides a synthesis of our discussions and is necessary for interpreting the proposals of this Special-purpose Committee to change aspects of Div. III (Provisions for gov-ernance) of the Code (Landrum & al. in Taxon 70: 1397-1398. 2021). This report and those proposals should be consulted together
Peptides to Tackle Leishmaniasis: Current Status and Future Directions
Get PDFPeptide-based drugs are an attractive class of therapeutic agents, recently recognized by the pharmaceutical industry. These molecules are currently being used in the development of innovative therapies for diverse health conditions, including tropical diseases such as leishmaniasis. Despite its socioeconomic influence on public health, leishmaniasis remains long-neglected and categorized as a poverty-related disease, with limited treatment options. Peptides with antileishmanial effects
encountered to date are a structurally heterogeneous group, which can be found in different natural sources—amphibians, reptiles, insects, bacteria, marine organisms, mammals, plants, and others—or inspired by natural toxins or proteins. This review details the biochemical and structural characteris tics of over one hundred peptides and their potential use as molecular frameworks for the design of
antileishmanial drug leads. Additionally, we detail the main chemical modifications or substitutions of amino acid residues carried out in the peptide sequence, and their implications in the development of antileishmanial candidates for clinical trials. Our bibliographic research highlights that the action of leishmanicidal peptides has been evaluated mainly using in vitro assays, with a special emphasis on the promastigote stage. In light of these findings, and considering the advances in the successful
application of peptides in leishmaniasis chemotherapy, possible approaches and future directions are discussed here
Assessment of Microplastic and Organophosphate Pesticides Contamination in Fiddler Crabs from a Ramsar Site in the Estuary of Guayas River, Ecuador.
Get PDFWe assessed the concentration of organophosphate pesticides (OPs) and microplastics (MPs) in water and sediments from the burrows, and tissues of the fiddler crabs Leptuca festae and Minuca ecuadoriensis, from Isla Santay, a Ramsar site in the estuary of the Guayas River, Ecuador. MPs concentrations in the burrows were 660 ± 174.36 items kg−1 (w.w.) and 26 ± 1 items L−1 in collected sediments and water, respectively. Regarding OPs, water and sediment concentrations were up to 26 times above the USEPA thresholds for chronic exposure, indicating environmental risk. MPs were found in tissues collected from both species. The highest abundance was in the gills followed by the digestive tract and hepatopancreas. OPs concentrations in tissues were below the detection limits. Because fiddler crabs are chronically exposed to environmental contamination, they are suitable bioindicators to monitor Isla Santay and to comprehend human impacts in coastal environments of Ecuador