RESUMO
Throughout the golden age of antibiotic discovery, Streptomyces have been unsurpassed for their ability to produce bioactive metabolites. Yet, this success has been hampered by rediscovery. As we enter a new stage of biodiscovery, omics data and existing scientific repositories can enable informed choices on the biodiversity that may yield novel antibiotics. Here, we focus on the chemical potential of rare actinomycetes, defined as bacteria within the order Actinomycetales, but not belonging to the genus Streptomyces. They are named as such due to their less-frequent isolation under standard laboratory practices, yet there is increasing evidence to suggest these biologically diverse genera harbour considerable biosynthetic and chemical diversity. In this review, we focus on examples of successful isolation and genera that have been the focus of more concentrated biodiscovery efforts, we survey the representation of rare actinomycete taxa, compared with Streptomyces, across natural product data repositories in addition to its biosynthetic potential. This is followed by an overview of clinically useful drugs produced by rare actinomycetes and considerations for future biodiscovery efforts. There is much to learn about these underexplored taxa, and mounting evidence suggests that they are a fruitful avenue for the discovery of novel antimicrobials.
Assuntos
Actinobacteria , Streptomyces , Actinobacteria/genética , Actinobacteria/metabolismo , Actinomyces , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Streptomyces/genética , BiodiversidadeRESUMO
Last year ActinoBase, a Wiki-style initiative supported by the UK Microbiology Society, published a review highlighting the research of particular interest to the actinomycete community. Here, we present the second ActinoBase review showcasing selected reports published in 2020 and early 2021, integrating perspectives in the actinomycete field. Actinomycetes are well-known for their unsurpassed ability to produce specialised metabolites, of which many are used as therapeutic agents with antibacterial, antifungal, or immunosuppressive activities. Much research is carried out to understand the purpose of these metabolites in the environment, either within communities or in host interactions. Moreover, many efforts have been placed in developing computational tools to handle big data, simplify experimental design, and find new biosynthetic gene cluster prioritisation strategies. Alongside, synthetic biology has provided advances in tools to elucidate the biosynthesis of these metabolites. Additionally, there are still mysteries to be uncovered in understanding the fundamentals of filamentous actinomycetes' developmental cycle and regulation of their metabolism. This review focuses on research using integrative methodologies and approaches to understand the bigger picture of actinomycete biology, covering four research areas: i) technology and methodology; ii) specialised metabolites; iii) development and regulation; and iv) ecology and host interactions.
Assuntos
Actinobacteria , Actinobacteria/genética , Actinomyces , Antibacterianos , Família Multigênica , Biologia SintéticaRESUMO
En la literatura científica mundial, existen muchos estudios que demuestran la capacidad antimicrobiana de diferentes hierbas, incluyendo el té verde. No obstante, muchos resultados son divergentes o no comparables. También, existen en el mercado muchas formulaciones de té verde, de las cuales hay poca información respecto a su actividad. En el presente trabajo se determinó el potencial efecto antimicrobiano contra cepas de Escherichia coli, Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus, Candida albicans y Aspergillus niger de 50 muestras diferentes de té verde seco y en infusión al 10%, distribuidas de manera comercial en Costa Rica. Se contrastó su actividad con la del té verde (Camellia sinensis) de origen chino. Se evaluaron diferentes solventes para preparar extractos ricos en polifenoles a partir del té verde. Los fenoles totales se determinaron mediante el método espectrofotométrico de Folin-Ciocalteu usando el ácido gálico como material de referencia. La evaluación de la capacidad antimicrobiana del extracto y las infusiones de té verde se llevó a cabo mediante el método de microplatos descrito por Breukink (2006). El etanol fue el solvente que mostró mayor eficiencia. No hubo efecto antimicrobiano de las diferentes muestras contra los microorganismos evaluados, excepto con Listeria monocytogenes, dondese evidenció un efecto inhibitorio en las concentraciones de 10,5 y 1,05 mg/mL de los extractos en el 70% de marcas analizadas y en el control. Ninguna de las infusiones evaluadas, incluyendo la del té control mostró efecto inhibitorio contra esta bacteria.
Many studies can be found in scientific literature demonstrating the antimicrobial capacity of different herbs, including green tea. Nevertheless, many results are divergent or cannot be compared. Several green tea formulations may be found in market, but there is scarce or non-information about its activity. In this work, the potential antimicrobial effect of 50 samples of dry green tea and in 10% infusion against Escherichia coli, Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus, Candida albicans and Aspergillus niger distributed in the metropolitan area of Costa Rica, was determined. This activity was compared with the effect produced by Chinese origin green tea (Camellia sinensis). Different solvents were evaluated for preparing polyphenol enriched extracts from green tea samples. Total phenols were determined using the Folin-Ciocalteu spectrophotometric methodology, using galic acid as reference. Antimicrobial activity of green tea extracts and infusions was evaluated using the microplate methodology described by Breuking (2006). Ethanol was the most efficient solvent used for the polyphenol extractions. There was no antimicrobial effect of the different green tea extracts and infusions against the microorganisms evaluated, except for Listeria monocytogenes, where the extracts of 70% of samples analyzed and the control showed an inhibitory effect in the 10,5 mg/mL and 1,05 mg/L concentrations. None of the infusions tested, including the control, showed any effect against this bacteria.
Assuntos
Antibacterianos/farmacologia , Camellia sinensis/química , Testes de Sensibilidade Microbiana , Chá/química , Antibacterianos/isolamento & purificação , Aspergillus niger/efeitos dos fármacos , Costa Rica , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Salmonella enterica/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacosRESUMO
Antecedentes. Por ser la enfermedad hipertensiva de carácter asintomático, el problema de la adherencia al tratamiento de pacientes hipertensos puede ser grave. Objetivo. Estudiar la adherencia al tratamiento de los pacientes hipertensos atendidos en la ciudad de Manizales (Colombia) por el programa ASSBASALUD E.S.E en el año 2011. Materiales y métodos. Estudio de corte transversal en el cual se empleó una población de 200 personas hipertensas (73,5% femenino, edad media 63,76 años) atendidas en ASSBASALUD ESE, Manizales, en el segundo semestre de 2011. Se empleó el cuestionario Martín-Bayarre-Grau (MBG) y el cuestionario de Morinsky-Green para evaluar la red de apoyo social y se empleó el cuestionario Medical OutcomesStudy (MOS). Resultados. Adherentes totales 45% según Morinsky-Green, adherentes totales 51% según MBG, respecto al cuestionario MOS se tiene, 12,29 personas en promedio en su red de apoyo social, apoyo emocional de 74,83%, ayuda material 80,45%, relaciones sociales de ocio y distracción de 78,61%, apoyo afectivo de 83,28%, el fármaco más empleado fue enalapril 17,9%, seguido de verapamilo 10,1%. La adherencia según el cuestionario MBG mostró dependencia significativa entre variables como: educación (p=0,000), conocimientos de la patología (p=0,032), y con los resultados del cuestionario de apoyo social, MOS (p=0,000). La adherencia según Morinsky-Green mostró muy pocas relaciones significativas. Conclusión. La población en estudio presenta bajos niveles de adherencia asociada a baja educación, bajos conocimientos de la patología, bajo apoyo social, se hace necesario una intervención efectiva de ASSBASALUD ESE, a través de su personal de salud. El cuestionario MBG mostró mayor consistencia en la descripción de la adherencia que el cuestionario de Morinsky-Green.
Background. Difficulties regarding patient adherence when treating hypertension could be extremely serious as one is dealing with an asymptomatic hypertensive disease. Objective. Studying adherence to treatment concerning hypertensive patients being attended in Manizales, Colombia, by the state-run Assbasalud programme in 2011. Materials and Methods. This was a cross-sectional study involving a population of 200 hypertensive people (73.5% were female, average age was 63.76 years) being attended by the state-run Assbasalud ESE, Manizales, during the second half of 2011. The Martín-Bayarre-Grau (MBG) and Morisky-Green (MG) questionnaires were used for evaluating the social support network, as well as the Medical Outcomes Study (MOS) questionnaire. Results.45% of patients were totally adherent according to MG and 51% totally adherent according to MBG. Regarding the MOS questionnaire, 12.29 people on average were in a patient's social support network, 74.83% received emotional support, 80.45% material aid, 78.61% were involved in leisure and entertainment-related activities, 83.28% were receiving affective support and enalapril was the drug most used in treatment (17.9%), followed by verapamil (10.1%). According to the MBG questionnaire, adherence significantly depended on variables such as education (p=0.000), knowledge about the disease (p=0.032) and MOS social support questionnaire results (p=0.000). The MG questionnaire revealed very few significant relationships for treatment adherence. Conclusion. The study revealed low adherence levels associated with having a low educational level, poor knowledge regarding the disease and poor social support, thereby making it necessary that Assbasalud ESE take more effective action, especially through its healthcare personnel. The MBG questionnaire had greater consistency regarding a description of adherence than the MG questionnaire.