Complete genome sequence of a Pseudomonas putida clinical isolate, strain H8234

We report the complete genome sequence of Pseudomonas putida strain H8234, which was isolated from a hospital patient presenting with bacteremia. This strain has a single chromosome (6,870,827 bp) that contains 6,305 open reading frames. The strain is not a pathogen but exhibits multidrug resistance associated with 40 genomic islands

Iron Uptake Analysis in a Set of Clinical Isolates of Pseudomonas putida

Pseudomonas putida strains are frequent inhabitants of soil and aquatic niches and they are occasionally isolated from hospital environments. As the available iron sources in human tissues, edaphic, and aquatic niches are different, we have analyzed iron-uptake related genes in different P. putida strains that were isolated from all these environments. We found that these isolates can be grouped into different clades according to the genetics of siderophore biosynthesis and recycling. The pyoverdine locus of the six P. putida clinical isolates that have so far been completely sequenced, are not closely related; three strains (P. putida HB13667, HB3267, and NBRC14164T) are grouped in Clade I and the other three in Clade II, suggesting possible different origins and evolution. In one clinical strain, P. putida HB4184, the production of siderophores is induced under high osmolarity conditions. The pyoverdine locus in this strain is closely related to that of strain P. putida HB001 which was isolated from sandy shore soil of the Yellow Sea in Korean marine sand, suggesting their possible origin, and evolution. The acquisition of two unique TonB-dependent transporters for xenosiderophore acquisition, similar to those existing in the opportunistic pathogen P. aeruginosa PAO, is an interesting adaptation trait of the clinical strain P. putida H8234 that may confer adaptive advantages under low iron availability conditions.Work in our laboratories was supported by ERANET Pathogenomics program through the ADHERS project (Ref: BIO2008-04419-E) and Fondos FEDER from the European Union through project BIO2010-17227 of the Spanish Ministry of Economy and Competitivity. The work in Abengoa Research was funded by H2020 grant Empowerputida number 65703.Peer reviewedPeer Reviewe

Cyclopropane fatty acids are involved in organic solvent tolerance but not in acid stress resistance in Pseudomonas putida DOT-T1E

Bacterial membranes constitute the first physical barrier against different environmental stresses. Pseudomonas putida DOT-T1E accumulates cyclopropane fatty acids (CFAs) in the stationary phase of growth. In this strain the cfaB gene encodes the main cyclopropane synthase responsible of the synthesis of CFAs, and its expression is mediated by RNA polymerase with sigma factor σ38. We generated a cfaB mutant of P. putida DOT-T1E and studied its response to solvents, acid pH and other stress conditions such as temperature changes, high osmolarity and the presence of antibiotics or heavy metals in the culture medium. A CfaB knockout mutant was more sensitive to solvent stress than the wild-type strain, but in contrast to Escherichia coli and Salmonella enterica, the P. putida cfaB mutant was as tolerant to acid shock as the wild-type strain. The cfaB mutant was also as tolerant as the parental strain to a number of drugs, antibiotics and other damaging agents

Gas–Solid Heterogeneous Postsynthetic Modification of Imine-Based Covalent Organic Frameworks

This is the peer-reviewed version of the following article: Martín-Illian, J. A., Royuela, S., Ramos, M. M., Segura, J. L., & Zamora, F. (2020). Gas‐Solid Heterogeneous Post‐Synthetic Modification of Imine‐based Covalent Organic Frameworks. Chemistry–A European Journal. 26 (29), 6495-6498, which has been published in final form at https://doi.org/10.1002/chem.202000224. This article may be used for non-commercial purposes in accordance with Wiley-VCH Terms and Conditions for Self-ArchivingThe copper-catalyzed azide–alkyne cycloaddition (CuAAC) click reaction is among the most extensively used strategies for the post-polymerization modification of COFs. This work shows a new procedure for the postsynthetic functionalization of imine-based COFs by using a heterogeneous solid–gas reaction between alkyne-functionalized COFs and azides in the absence of a copper catalyst. This new alternative represents a step forward towards a greener postsynthetic modification of COFs opening a high potential for the development of new applicationsThis work was financially supported by MINECO (MAT2016‐77608‐C3‐1‐P and 2‐P

Spread of the invasive alga Caulerpa racemosa var. cylindracea (Caulerpales, Chlorophyta) along the Mediterranean Coast of the Murcia region (SE Spain)

The aim of this paper was to document the appearance and spread of the green alga Caulerpa racemosa along the coast of Murcia in south–eastern Spain. It was found for the first time in the area in 2005 and over the next two years the number of new sightings increased almost exponentially. In the period 2005–2007 the total surface area colonised by the alga in the region was estimated to be at least 265 ha. Benthic assemblages colonised by the alga were rocky bottoms with photophilic algae, dead P. oceanica rhizomes, infralittoral and circalittoral soft bottoms and maerl beds. No penetration of the alga was observed in P. oceanica meadows, except in one locality. Biometric analysis indicated high vegetative development in the established colonies in comparison to those described in other Mediterranean areas. Rapid spreading dynamics observed in the Murcia region is a potential threat for native benthic communities. Key words: Biological invasions, Caulerpa racemosa var. cylindracea, Colonised surface area, Distribution, Mediterranean Sea, Spain.En el presente trabajo se documenta la aparición y dispersión del alga verde Caulerpa racemosa a lo largo de la costa de Murcia, región situada en el sureste español. El alga fue detectada por primera vez en el año 2005 y durante los dos años consecutivos se observó un crecimiento casi exponencial en el número de áreas colonizadas. La superficie total colonizada por el alga en Murcia durante el periodo 2005–2007 ha sido estimada en 265 ha., siendo las comunidades bentónicas afectadas algas fotófilas sobre sustrato rocoso, "mata muerta" de P. oceanica, fondos blandos infralitorales y circalitorales y fondos con comunidades de maërl. La presencia del alga dentro de praderas de P. oceanica solamente fue detectada en una localidad. Los estudios biométricos realizados muestran un elevado desarrollo vegetativo de las poblaciones de C. racemosa en Murcia en comparación con colonias de otras áreas del Mediterráneo, siendo esta rápida dinámica de expansión una amenaza potencial para las comunidades bentonicas nativas. Palabras clave: Invasiones biológicas, Caulerpa racemosa var. cylindracea, Superficie colonizada, Mar Mediterraneo, España.The aim of this paper was to document the appearance and spread of the green alga Caulerpa racemosa along the coast of Murcia in south–eastern Spain. It was found for the first time in the area in 2005 and over the next two years the number of new sightings increased almost exponentially. In the period 2005–2007 the total surface area colonised by the alga in the region was estimated to be at least 265 ha. Benthic assemblages colonised by the alga were rocky bottoms with photophilic algae, dead P. oceanica rhizomes, infralittoral and circalittoral soft bottoms and maerl beds. No penetration of the alga was observed in P. oceanica meadows, except in one locality. Biometric analysis indicated high vegetative development in the established colonies in comparison to those described in other Mediterranean areas. Rapid spreading dynamics observed in the Murcia region is a potential threat for native benthic communities. Key words: Biological invasions, Caulerpa racemosa var. cylindracea, Colonised surface area, Distribution, Mediterranean Sea, Spain

PANIC: the new panoramic NIR camera for Calar Alto

PANIC is a wide-field NIR camera, which is currently under development for the Calar Alto observatory (CAHA) in Spain. It uses a mosaic of four Hawaii-2RG detectors and covers the spectral range from 0.8-2.5 micron(z to K-band). The field-of-view is 30x30 arcmin. This instrument can be used at the 2.2m telescope (0.45arcsec/pixel, 0.5x0.5 degree FOV) and at the 3.5m telescope (0.23arcsec/pixel, 0.25x0.25 degree FOV). The operating temperature is about 77K, achieved by liquid Nitrogen cooling. The cryogenic optics has three flat folding mirrors with diameters up to 282 mm and nine lenses with diameters between 130 mm and 255 mm. A compact filter unit can carry up to 19 filters distributed over four filter wheels. Narrow band (1%) filters can be used. The instrument has a diameter of 1.1 m and it is about 1 m long. The weight limit of 400 kg at the 2.2m telescope requires a light-weight cryostat design. The aluminium vacuum vessel and radiation shield have wall thicknesses of only 6 mm and 3 mm respectively.Comment: This paper has been presented in the SPIE of Astronomical Telescopes and Instrumentation 2008 in Marseille (France

Catalytically Active Imine-based Covalent Organic Frameworks for Detoxification of Nerve Agent Simulants in Aqueous Media

A series of imine-based covalent organic frameworks decorated in their cavities with di erent alkynyl, pyrrolidine, and N-methylpyrrolidine functional groups have been synthetized. These materials exhibit catalytic activity in aqueous media for the hydrolytic detoxification of nerve agents, as exemplified with nerve gas simulant diisopropylfluorophosphate (DIFP). These preliminary results suggest imine-based covalent organic frameworks (COFs) as promising materials for detoxification of highly toxic molecules.MINECO (MAT2016-77608-C3-1-P and 2-P, CTQ2017-84692-R) and EU FEDER fundin

Photo-acclimatory thresholds anticipate sudden shifts in seagrass ecosystem state under reduced light conditions

Seagrass ecosystems usually respond in a nonlinear fashion to increasing pressures and environmental changes. Feedback mechanisms operating at the ecosystem level and involving multiple interactions among the seagrass meadow, its associated community and the physical environment are known to play a major role in such nonlinear responses. Phenotypic plasticity may also be important for buffering these ecological thresholds (i.e., regime shifts) as many physiological processes show nonlinear responses to gradual environmental changes, conferring the appearance of resistance before the effects at the organism and population levels are visible. However, the potential involvement of plant plasticity in driving catastrophic shifts in seagrass ecosystems has not yet been assessed. In this study, we conducted a manipulative 6-month light-gradient experiment in the field to capture nonlinearities of the physiological and population responses of the seagrass Cymodocea nodosa to gradual light reduction. The aim was to explore if and how the photo-acclimatory responses of shaded plants are translated to the population level and, hence, to the ecosystem level. Results showed that the seagrass population was rather stable under increasing shading levels through the activation of multilevel photo-acclimative responses, which are initiated with light reduction and modulated in proportion to shading intensity. The activation of photo-physiological and metabolic compensatory responses allowed shaded plants to sustain nearly constant plant productivity (metabolic carbon balance) along a range of shading levels before losing linearity and starting to decline. The species then activated plant- and meadow-scale photo-acclimative responses and drew on its energy reserves (rhizome carbohydrates) to confer additional population resilience. However, when the integration of all these buffering mechanisms failed to counterbalance the effects of extreme light limitation, the population collapsed, giving place to a phase shift from vegetated to bare sediments with catastrophic ecosystem outcomes. Our findings evidence that ecological thresholds in seagrass ecosystems under light limitation can be explained by the role of species’ compensatory responses in modulating population-level responses. The thresholds of these plastic responses anticipate the sudden loss of seagrass meadows with the potential to be used as early warning indicators signalling the imminent collapse of the ecosystem, which is of great value for the real-world management of seagrass ecosystems.En prens

Long-term coexistence between the macroalga Caulerpa prolifera and the seagrass Cymodocea nodosa in a Mediterranean lagoon

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