Streptomycetes are widely distributed in the marine environment, although only a few studies on their associations to algae and coral ecosystems have been reported. Using a culture-dependent approach, we have isolated antibiotic-active Streptomyces species associated to diverse intertidal marine macroalgae (Phyllum Heterokontophyta, Rhodophyta, and Chlorophyta), from the central Cantabrian Sea. Two strains, with diverse antibiotic and cytotoxic activities, were found to inhabit these coastal environments, being widespread and persistent over a 3-year observation time frame. Based on 16S rRNA sequence analysis, the strains were identified as Streptomyces cyaneofuscatus M-27 and Streptomyces carnosus M-40. Similar isolates to these two strains were also associated to corals and other invertebrates from deep-sea coral reef ecosystem (Phyllum Cnidaria, Echinodermata, Arthropoda, Sipuncula, and Anelida) living up to 4.700-m depth in the submarine Avilés Canyon, thus revealing their barotolerant feature. These two strains were also found to colonize terrestrial lichens and have been repeatedly isolated from precipitations from tropospheric clouds. Compounds with antibiotic and cytotoxic activities produced by these strains were identified by high-performance liquid chromatography (HPLC) and database comparison. Antitumor compounds with antibacterial activities and members of the anthracycline family (daunomycin, cosmomycin B, galtamycin B), antifungals (maltophilins), anti-inflamatory molecules also with antituberculosis properties (lobophorins) were identified in this work. Many other compounds produced by the studied strains still remain unidentified, suggesting that Streptomyces associated to algae and coral ecosystems might represent an underexplored promising source for pharmaceutical drug discovery.
Members of the Streptomyces albidoflavus clade, identified by 16S rRNA sequencing and phylogenetic analyses, are widespread among predominant terrestrial lichens (Flavoparmelia caperata and Xanthoria parietina) and diverse intertidal and subtidal marine macroalgae, brown red and green (Phylum Heterokontophyta, Rhodophyta, and Chlorophyta) from the Cantabrian Cornice. In addition to these terrestrial and coastal temperate habitats, similar strains were also found to colonize deep-sea ecosystems and were isolated mainly from gorgonian and solitary corals and other invertebrates (Phylum Cnidaria, Annelida, Echinodermata, Arthropoda, and Porifera) living up to 4700-m depth and at a temperature of 2-4 °C in the submarine Avilés Canyon. Similar strains have been also repeatedly isolated from atmospheric precipitations (rain drops, snow, and hailstone) collected in the same area throughout a year observation time. These ubiquitous strains were found to be halotolerant, psychrotolerant, and barotolerant. Bioactive compounds with diverse antibiotic and cytotoxic activities produced by these strains were identified by high-performance liquid chromatography (HPLC) and database comparison. These include antibacterials (paulomycins A and B), antifungals (maltophilins), antifungals displaying also cytotoxic activities (antimycins and 6-epialteramides), and the antitumor compound fredericamycin. A hypothetical dispersion model is here proposed to explain the biogeographical distribution of S. albidoflavus strains in terrestrial, marine, and atmospheric environments.
Cires, E., Cuesta, C., Fernández, M.A., Nava, H.S. Flow cytometry analysis has been widely applied in the determination of nuclear DNA content and ploidy level in many organisms. Despite being the most appropriate method for DNA content measurement, flow cytometry also presents some limitations. A fairly common, but little-studied problem is the effect on measurements of the presence of secondary metabolites. A good example is the genus Viola, which is composed of 525-600 species distributed worldwide. These species have proved to be problematic for flow cytometric analyses due to the release of extremely mucilaginous compounds into the nuclear suspension. In this work, the genome size of 13 species of Viola using flow cytometry are presented for the first time. Despite obtaining histograms with high coefficients of variation, we here present an optimized protocol to remove cytoplasmic compounds, particularly mucilaginous ones, from plant nuclei that pave the way for its application to estimate the genome size of other species exhibiting similar problems. Statistical analyses revealed significant differences between sections Viola and Melanium, and within each section (P < 0.001). Furthermore, statistically significant differences were not detected among samples of the same species. ResumenCires, E., Cuesta, C., Fernández, M.A., Nava, H.S., Vázquez, V.M. & Fernández, J.A. 2011. Aislamiento de núcleos para citometría de flujo en plantas con alto contenido de compuestos mucilaginosos: un ejemplo en el género Viola L. (Violaceae). Ana les Jard. Bot. Madrid 68(2): 139-154 (en inglés).El análisis mediante citometría de flujo ha sido aplicado de modo general para determinar el contenido de ADN nuclear y el nivel de ploidía en muchos organismos. A pesar de ser el método más adecuado para medir la cantidad de ADN, esta técnica también presenta algunas limitaciones. Un problema bastante común, aunque poco estudiado, es el efecto de los metabolitos secundarios en los resultados obtenidos. Un ejemplo respecto a la presencia de estos compuestos se encuentra en el género Viola, compuesto por 525-600 especies distribuidas por todo el mundo. Las especies de este género ya han sido previamente descritas como problemáticas en los análisis de citometría de flujo debido a la presencia de compuestos extremadamente mucilaginosos en las suspensiones de núcleos. En el presente trabajo se analiza por primera vez el tamaño genómico de 13 especies del genero Viola mediante el empleo de citometría de flujo. A pesar de los altos valores mostrados en los coeficientes de variación de los histogramas, se presenta un protocolo optimizado para eliminar compuestos citoplasmáticos, y más concretamente mucilaginosos de las suspensiones nucleares, siendo de aplicación en la estimación del tamaño genómico de plantas con problemas similares. Los análisis estadísticos mostraron diferencias significativas entre las secciones Viola y Melanium, así como dentro de cada sección (P < 0,001). Además, no se encontraron diferencias significativas entre...
We present the first standardized list of the vascular flora of the Cantabrian Mountains, a transitional zone between the Eurosiberian and Mediterranean biogeographic regions in northwestern Spain. The study area comprises 15000 km2 divided in UTM grid cells of 10 km x 10 km, for which we revised occurrence data reported in the Spanish Plant Information System (Anthos) and the online database of Iberian and Macaronesian Vegetation (SIVIM). We used a semi-automatic procedure to standardize taxonomic concepts into a single list of names, which was further updated by expert-based revision with the support of national and regional literature. In the current version, the checklist of the Cantabrian Mountains contains 2338 native species and subspecies, from which 56 are endemic to the study area. The nomenclature of the checklist follows Euro+Med in 97% of taxa, including annotations when other criteria has been used and for taxa with uncertain status. We also provide a list of 492 non-native taxa that were erroneously reported in the study area, a list of local apomictic taxa, a phylogenetic tree linked to The Plant List, a standardized calculation of Ellenberg Ecological Indicator Values for 80% of the flora, and information about life forms, IUCN threat categories and legal protection status. Our review demonstrates how the Cantabrian mountains represent a key floristic region in southern Europe and a relevant phytogeographical hub in south-western Europe. The checklist and all related information are freely accessible in a digital repository for further uses in basic and applied research
FERNANDEZ PRIETO, J. A., VERA, M. L., ALVAREZ MARTINEZ, M. J., DIAZ, T. E., FERNANDEZ CASADO, M. A., FERNANDEZ‐CARVAJAL, M. C, GUTIERREZ VILLARIAS, M. I. & NAVA, H. S., 1993. Chromosome numbers and geographical distribution of Ulex europaeus subsp. europaeus (Leguminosae). Chromosome numbers are reported in Ulex europaeus subsp. europaeus (99 samples from northern Spain, France and Great Britain). Three levels of ploidy (diploid, tetraploid and hexaploid) have been detected; the diploid and tetraploid levels, hitherto unknown in this taxon, have been found exclusively in coastal areas of northern Spain and western France.
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