Ana Bartual

Universidad de Cádiz | UCA · Department of Biology

Microbial associations and interactions drive and regulate nutrient fluxes in the ocean. However, physical contact between cells of marine cyanobacteria has not been studied thus far. Here, we show a mechanism of direct interaction between the marine cyanobacteria Prochlorococcus and Synechococcus , the intercellular membrane nanotubes. We present...

Diatoms are responsible for the fixation of ca. 20% of the global CO2 and live associated with bacteria that utilize the organic substances produced by them. Current research trends in marine microbial ecology show which diatom and bacteria interact mediated through the production and exchange of infochemicals. Polyunsaturated aldehydes (PUA) are o...

Numerous microbial associations and interactions drive and regulate nutrient fluxes in the ocean. Symbiotic interactions are the best example and are key drivers of ecological diversification and evolutionary innovation on Earth¹. Besides symbiotic, other kinds of interactions exist between free-living bacteria; for example, the uptake of shared me...

El pasado 22 de mayo de 2022 tuvo lugar en el bar "La Casapuerta" (c/ Sagasta 40, Cádiz) una charla y showcooking en el que las algas fueron las protagonistas. Esta actividad se enmarcó dentro del calendario de actividades culturales en torno a la gastronomía que oferta, desde hace más de un lustro, este establecimiento regentado por Luisa Barrios...

The photosymbiosis with host-specific dinoflagellates is a widespread relationship in marine organisms. Despite the evidenced biodiversity of this kind of mutualism, most research focuses on the study of scleractinian corals, and there is a lack of knowledge about other symbiotic cnidarians such as jellyfishes. The Mediterranean jellyfish Cotylorhi...

Species of the genus Tetraselmis have traditionally been used as a valuable nutritional source in aquaculture for their high fatty acid content (5–10% dry weight). Their use in nutraceutical production for humans is growing worldwide. Among them, Tetraselmis chui is generally reported as rich in polyunsaturated fatty acids (PUFAs), especially eicos...

The temporal evolution of the physical and biogeochemical properties of the Atlantic Jet (AJ) along the first ∼ 75 m of the water column during a 4-day journey was analysed by following the trajectory of a drifter dragged by the jet from the Strait of Gibraltar towards the Alborán Sea. Three stages were differentiated based on the evolution of seve...

The surge of research on marine litter is generating important information on its inputs, distribution and impacts, but data on the nature and origin of the litter remain scattered. Here, we harmonize worldwide litter-type inventories across seven major aquatic environments and find that a set of plastic items from take-out food and beverages large...

This topic intends to cover a wide range of interesting subjects related to the diversity and adaptation of phytoplankton communities across time and environments, by including original research papers, perspectives, and reviews. This topic welcomes content related to understanding phytoplankton’s strategies, associations and interactions between d...

Polyunsaturated aldehydes (PUAs) are bioactive molecules suggested as chemical defenses and infochemicals. In marine coastal habitats, diatoms reach high PUA production levels during bloom episodes. Two fractions of PUA can usually be analyzed: pPUA obtained via artificial breakage of collected phytoplankton cells and dissolved PUA already released...

Caffeine is a potent stimulant of nervous system typically found in aquatic environment in a range between 1 to 293 𝜇g·L-1. This compound is abundant in municipal wastewater effluents, and once at the environment, it has been reported may cause damage on the aquatic organisms affecting natural biodiversity of aquatic areas near these effluents. Dur...

The polyunsaturated aldehydes (PUAs) are bioactive metabolites commonly released by phytoplankton species. Based primarily on laboratory experiments, PUAs have been implicated in deleterious effects on herbivores and competing phytoplankton species or in the regulation of the rates of bacterial organic matter remineralization; however, the role of...

Los aldehídos poliinsaturados (PUAs) son compuestos orgánicos volátiles derivados de ácidos grasos poliinsaturados, producidos y liberados al medio marino por diferentes grupos fitoplanctónicos. Experimentalmente se han propuesto diferentes funciones biológicas de dichos compuestos, como de defensa química frente a depredadores (Caldwell, 2009), o...

Polyunsaturated aldehydes (PUA) are bioactive molecules released by phytoplankton cells which can modify phytoplankton trophic interactions with grazers, bacteria or coexisting phytoplankters. Their ecological significance is still a matter of debate. There have been reports of PUA producers having been investigated at the ocean surface in both coa...

Diatoms constitute a widespread group of phytoplanktonic species that thrive in coastal waters and produce episodical blooms. During these blooms, these diatoms release several organic compounds into the environment. Two types of organic molecules released by diatoms are the polyunsaturated aldehydes (PUA) and exopolymeric substances (EPS). EPS can...

Macrophytes and microalgae for cooking

Nowadays, several pathogenic bacteria present resistance against common antibiotics, being necessary the search new drugs with activity against resistant pathogens. The capacity of microalgae to produce diverse secondary metabolites has been widely reported. Here we searched the antibacterial activity of several organic extracts from different micr...

The aim of this work was to study the optimal growth and high value-added production of the microalgae Coelastrum cf. pseudomicroporum Korshikov cultivated in urban wastewater. It was observed that C. cf. pseudomicroporum grew ideally in this medium, acting as an efficient nutrient starver. Additionally, the obtained biomass increased carotenoid ce...

Taller de divulgación desarrollado en los Campus científicos de verano de 2016 sobre el uso de algas en la cocina

The Alborán sea is a highly dynamic area connecting the Strait of Gibraltar with the rest of the western basin of the Mediterranean Sea. It is an area characterized by mesoscale processes that strongly affect several biological processes and, therefore, the physiological state of the phytoplanktonic assemblage. The aim of this research is to analyz...

Diatoms, a major component of the large-sized phytoplankton, are able to produce and release polyunsaturated aldehydes after cell disruption (potential PUAs or pPUA). These organisms are dominant in the large phytoplankton fraction (>10 µm) in the Strait of Gibraltar, the only connection between the Mediterranean Sea and the Atlantic Ocean. In this...

Polyunsaturated aldehydes (PUAs) are organic compounds mainly produced by diatoms, after cell wounding. These compounds are increasingly reported as teratogenic for species of grazers and deleterious for phytoplanktonic species, but there is still scarce information regarding concentration ranges and the composition of PUAs in the open ocean. In th...

Polyunsaturated aldehydes (PUAs) are volatile compounds commonly released into the environment by different fresh and seawater phytoplankton species. Diatoms are among the main producers of these metabolites in seawater. The release of these metabolites in seawater is known to be wound-activated as a consequence of predation or cell lysis. Hence, t...

The higher growth rates of resprouting shoots compared with those of mature plants in resprouter woody species are supported by higher rates of photosynthesis and transpiration. In this contribution we hypothesize that species with higher resprouting vigour will show a larger enhancement of photosynthesis in resprouting shoots. We test this hypothe...

Physical processes forced by tidal dynamics, such as bores and internal waves, have a high influence on biological patterns in the main channel of the Strait of Gibraltar. To analyse this connection in the case of photosynthetic processes, a set of high resolution profiles of physical (temperature, salinity, and light) and chemical (nutrients and c...

Over the last decades Phaeodactylum tricornutum has become a model to study diatom biology at the molecular level. Cells have the peculiarity to be pleiomorphic and it is thought that this character is triggered by culture conditions, although few quantitative studies have been performed and nothing is known at the molecular level. Our aim was to q...

Phaeodactylum tricornutum Bohlin has long been considered as a representative model diatom, but critical uncertainties regarding its life cycle remain. It is characterized by a marked pleiomorphism with three basic morphotypes: triradiate, fusiform and oval. In liquid media, triradiate cells gradually convert into the fusiform morphotype, passing t...

This work presents the results of an interlaboratory proficiency exercise for whole-sediment toxicity assays with the benthic marine diatom Cylindrotheca closterium. An assay protocol was established and followed by all participating laboratories. Cell growth after 72 h exposure was the endpoint used. Four sediment samples of unknown toxicity were...

Primary production was studied at nine sites distributed within the Strait of Gibraltar (Southern Spain) and NorthWestern (NW) Alboran Sea by analyzing photosynthesis-irradiance (P–I) relationships and integrated primary production rates in relation to the different types of Deep Chlorophyll Maxima (DCM) detected in the area. The characteristics of...

Primary production was studied at nine sites distributed within the Strait of Gibraltar (Southern Spain) and North-Western (NW) Alboran Sea by analyzing photosynthesis-irradiance (P–I) relationships and integrated primary production rates in relation to the different types of Deep Chlorophyll Maxima (DCM) detected in the area. The characteristics o...

The physiology and biochemistry of Phaeodactylum tricornutum have been extensively studied, and some aspects of its biology are well known. Phenotypic plasticity is probably one of its most remarkable features. Two basic morphotypes, fusiform and triradiate, can be found in natural liquid environments. Although the transformation from one morphotyp...

This study explores whether male and hermaphrodite plants of Phillyrea angustifolia (Oleaceae) show physiological and structural differences at the leaf level under severe water stress driven by drought and soil salinity. Leaf traits were measured in summer, at the height of the summer drought period, in male and hermaphrodite plants from two adjac...

Unbuffered and nutrient-replete dilute batch cultures of Skeletonema costatum Cleve and Phaeodactylum tricornutum Bohlin were grown at high and low CO2 availability conditions and two incident irradiances, 150 and 30 mumol photons.m(-2).s(-1). Long-term combined effects of such light and CO2 availability conditions on carbon fixation rates of both...

The effects of different incident irradiances on growth, photosynthesis, pigment content and nutrient uptake were studied in dense cultures of the cryptophyte Rhodomonas salina (Wislouch) Hill y Wetherbee. Cells were grown for ten days at different incident irradiances: 11,33,75,260 and 320 μmol photon m-2s-1. The average pigment content (phycoeryt...

Diatoms and the large, fast-sinking aggregates they form during blooms play an important role in downward flux of particles in the ocean. To study how the aggregation process operates on particle dynamics, diatom blooms were generated and followed under controlled conditions in nutrient-enriched laboratory mesocosm where a homogeneous mixed surface...

The effects of pH and total dissolved inorganic carbon (DIC) availability on the growth and biochemical composition of Phaeodactylum tricornutum Bohlin acclimated to restricted and saturated light conditions have been investigated. Diluted, unbuffered and nutrient enriched batch cultures were grown at several pHs (different [CO2(aq)] for the same D...

Diatom aggregates are a significant component of the downward particle flux recorded by sediment traps during phytoplankton blooms. However, although these large parti- cles are an important vector for the transfer of carbon to the deep ocean, there is a lack of empirical approaches to formulate their generation at the ocean surface. There is also...

The surface distribution of light attenuation due to particles (c) as well as chlorophyll-a and gelbstoff fluorescence (Fch and Fcd, respectively) were recorded during an OMEGA (EU funded, MAST III project) cruise in the northwestern Alborán Sea through a high spatial (zonally separated by 10 km and virtually meridionally continuous) and temporal (...

The morphological and physiological differences between two morphotypes of Z. noltii Hornem. were studied in the intertidal meadows on the south-western Iberian Peninsula (Palmones river estuary and Ria Formosa). A small-leaved morphotype (SM) grows mainly at high intertidal sites, meadow edges or in recently deposited sandbanks, whereas a large-le...