Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria

The online version of this article (doi:10.1007/s00253-017-8212-x) contains supplementary material, which is available to authorized users.The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as denitrification tanks of WWTPs, nor about the bacteria involved in the anoxic biodegradation. Here, we used SLES as sole carbon and energy source, at concentrations ranging from 50 to 1000 mg L1, to enrich and isolate nitrate-reducing bacteria from activated sludge of a WWTP with the anaerobic-anoxic-oxic (A2/O) concept. In the 50 mg L1 enrichment, Comamonas (50%), Pseudomonas (24%), and Alicycliphilus (12%) were present at higher relative abundance, while Pseudomonas (53%) became dominant in the 1000 mg L1 enrichment. Aeromonas hydrophila strain S7, Pseudomonas stutzeri strain S8, and Pseudomonas nitroreducens strain S11 were isolated from the enriched cultures. Under denitrifying conditions, strains S8 and S11 degraded 500 mg L1 SLES in less than 1 day, while strain S7 required more than 6 days. Strains S8 and S11 also showed a remarkable resistance to SLES, being able to grow and reduce nitrate with SLES concentrations up to 40 g L1. Strain S11 turned out to be the best anoxic SLES degrader, degrading up to 41% of 500 mg L1. The comparison between SLES anoxic and oxic degradation by strain S11 revealed differences in SLES cleavage, degradation, and sulfate accumulation; both ester and ether cleavage were probably employed in SLES anoxic degradation by strain S11.This research was supported by the Spanish Ministry of Education and Science (contract project CTQ2007-64324 and 447 CONSOLIDER-CSD 2007-00055). The Regional Government of Castilla y Leon (Ref. GR76) is also gratefully acknowledged. MRD is supported by the WIMEK graduate school (project BAdaptive capacity and functionality of multi-trophic aquatic ecosystems^). AJMS is supported by the Gravitation grant (project 024.002.002) of the Netherlands Ministry of Education, Culture and Science and the Netherlands Science Foundation (NWO). AJMS and AJC are supported by an European ResearchCouncil (ERC) Grant (Project 323009).Thisstudywassupported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. This study was alsosupportedbythePortugueseFoundationforScienceandTechnology (FCT) under the scope of the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462). Joana Alves from University of Minho (Portugal) is acknowledged for support with the molecular techniques.info:eu-repo/semantics/publishedVersio

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Arbuscular mycorrhizal inoculation enhances plant growth and changes root system morphology in micropropagated Annona cherimola Mill

The effect of arbuscular mycorrhizal formation on plant development and root system morphogenesis in micropropagated Annona cherimola plants was investigated. A juvenile rootstock was used and already rooted in vitro plantlets were inoculated with arbuscular mycorrhizal propagules at the beginning of their acclimatization phase. Mycorrhization improved plant development (root, steam and leaves), but decreased the specific root length. Arbuscular mycorrhizal formation did not change the degree of branching nor the lateral root frequency for the adventitious roots, but significantly increased the intensity of branching of the first-order laterals. These results corroborate the role of arbuscular mycorrhizal symbiosis inducing beneficial changes in root system morphology and in the general developmental pattern in micropropagated plants.L'inoculation de mycorhizes arbusculaires augmente la croissance de la plante et change la morphologie du système racinaire d'Annona cherimola Mill micropropagés. L'effet de la formation de mycorhizes arbusculaires sur le développement de la plante et la morphogenèse du système racinaire d'Annona cherimola a été étudié. Un porte-greffe juvénile a été utilisé et des plantes déjà enracinées in vitro ont été inoculées avec des propagules de mycorhizes arbusculaires au début de la période d'acclimatation. La mycorhization améliore le développement de la plante (racines, tiges, feuilles) mais diminue la longueur spécifique des racines. La formation de mycorhizes arbusculaires ne change pas pour les racines adventives, ni le degré d'embranchement, ni la fréquence des racines latérales, mais augmente sensiblement l'intensité des branchements des racines de premier ordre. Ces résultats corroborent le rôle de la symbiose mycorhizienne dans l'induction de changements bénéfiques au niveau de la morphologie du système racinaire et en général du développement de plants micropropagés

An easy and reliable method for establishment and maintenance of leaf and root cell cultures of Arabidopsis thaliana

Cell suspension cultures are useful for a wide range of biochemical and physiological studies, yet their production can be technically demanding and often unreliable. Here we describe a protocol for producing Arabidopsis cell suspension cultures that is reliable and easy to use

Zinc tolerance and accumulation in stable cell suspension cultures and in vitro regenerated plants of the emerging model plant Arabidopsis halleri (Brassicaceae)

Arabidopsis halleri is increasingly employed as a model plant for studying heavy metal hyperaccumulation. With the aim of providing valuable tools for studies on cellular physiology and molecular biology of metal tolerance and transport, this study reports the development of successful and highly efficient methods for the in vitro regeneration of A. halleri plants and production of stable cell suspension lines. Plants were regenerated from leaf explants of A. halleri via a three-step procedure: callus induction, somatic embryogenesis and shoot development. Efficiency of callus proliferation and regeneration depended on the initial callus induction media and was optimal in the presence of 1 mg L−1 2,4-dichlorophenoxyacetic acid, and 0.05 mg L−1 benzylaminopurine. Subsequent shoot and root regeneration from callus initiated under these conditions reached levels of 100% efficiency. High friability of the callus supported the development of cell suspension cultures with minimal cellular aggregates. Characterization of regenerated plants and cell cultures determined that they maintained not only the zinc tolerance and requirement of the whole plant but also the ability to accumulate zinc; with plants accumulating up to 50.0 μmoles zinc g−1 FW, and cell suspension cultures 30.9 μmoles zinc g−1 DW. Together this work will provide the experimental basis for furthering our knowledge of A. halleri as a model heavy metal hyperaccumulating plant

Avocado (Persea americana Mill.)

Avocado (Persea americana Mill.) is an ancient tree species belonging to the Order Ranales and Family Lauraceae. At present, the demand for avocado is growing rapidly due to its high nutritional value and reported health benefits. Much of this demand is centred on only a few cultivated varieties despite there being vast genetic diversity in the species. Preservation of germplasm is a proactive approach to address future breeding needs and to safeguard the diversity of cultivated crops including avocado. Present conservation strategies for Avocado (Persea spp.) solely rely on field collections, as seeds are highly heterozygous and recalcitrant to long-term storage. However, these field banks are constantly exposed to abiotic and biotic stresses. Moreover, the size of the gene pool, number of replications and quality of maintenance are restrained by the local environmental conditions, space and funding. In this chapter we present a protocol for cryopreservation of avocado somatic embryos as an alternative to field banks for long-term storage of germplasm. The protocol describes all stages of a vitrification-based cryopreservation and regeneration technique including induction, maintenance, maturation, cryo-treatment and germination of somatic embryos. This in vitro regeneration and storage system for avocado will impose low risk and is a space efficient conservation method that will be beneficial for future improvement of this invaluable horticultural crop