Pyrolysed almond shells used as electrodes in microbial electrolysis cell

9 p.The large cost of components used in microbial electrolysis cell (MEC) reactors represents an important limitation that is delaying the commercial implementation of this technology. In this work, we explore the feasibility of using pyrolysed almond shells (PAS) as a material for producing low-cost anodes for use in MEC systems. This was done by comparing the microbial populations that developed on the surface of PAS bioanodes with those present on the carbon felt (CF) bioanodes traditionally used in MECs. Raw almond shells were pyrolysed at three different temperatures, obtaining the best conductive material at the highest temperature (1000 °C). The behaviour of this material was then verified using a single-chamber cell. Subsequently, the main test was carried out using two-chamber cells and the microbial populations extant on each of the bioanodes were analysed. High-throughput sequencing of the 16S rRNA gene for eubacterial populations was carried out in order to compare the microbial communities attached to each type of electrode. The microbial populations on each electrode were also quantified by real-time polymerase chain reaction (realtime PCR) to determine the amount of bacteria capable of growing on the electrodes’surface. The results indicated that the newly developed PAS bioanodes possess a biofilm similar to those found on the surface of traditional CF electrodes. This research was possible thanks to the financial support of the Junta de Castilla y León, and was financed by European Regional Development Funds (LE320P18). C. B. thanks the Spanish Ministerio de Educación, Cultura y Deporte for support in the form of an FPI fellowship grant (Ref #: BES-2016-078329)

The GPA-dependent, spherostomatocytosis mutant AE1 E758K induces GPA-independent, endogenous cation transport in amphibian oocytes

The previously undescribed heterozygous missense mutation E758K was discovered in the human AE1/SLC4A1/band 3 gene in two unrelated patients with well-compensated hereditary spherostomatocytic anemia (HSt). Oocyte surface expression of AE1 E758K, in contrast to that of wild-type AE1, required coexpressed glycophorin A (GPA). The mutant polypeptide exhibited, in parallel, strong GPA dependence of DIDS-sensitive 36Cl− influx, trans-anion-dependent 36Cl− efflux, and Cl−/HCO3− exchange activities at near wild-type levels. AE1 E758K expression was also associated with GPA-dependent increases of DIDS-sensitive pH-independent SO42− uptake and oxalate uptake with altered pH dependence. In marked contrast, the bumetanide- and ouabain-insensitive 86Rb+ influx associated with AE1 E758K expression was largely GPA-independent in Xenopus oocytes and completely GPA-independent in Ambystoma oocytes. AE1 E758K-associated currents in Xenopus oocytes also exhibited little or no GPA dependence. 86Rb+ influx was higher but inward cation current was lower in oocytes expressing AE1 E758K than previously reported in oocytes expressing the AE1 HSt mutants S731P and H734R. The pharmacological inhibition profile of AE1 E758K-associated 36Cl− influx differed from that of AE1 E758K-associated 86Rb+ influx, as well as from that of wild-type AE1-mediated Cl− transport. Thus AE1 E758K-expressing oocytes displayed GPA-dependent surface polypeptide expression and anion transport, accompanied by substantially GPA-independent, pharmacologically distinct Rb+ flux and by small, GPA-independent currents. The data strongly suggest that most of the increased cation transport associated with the novel HSt mutant AE1 E758K reflects activation of endogenous oocyte cation permeability pathways, rather than cation translocation through the mutant polypeptide

Role of Biofilms in Bioprocesses: A Framework for Multidimensional IBM Modelling of Heterogeneous Biofilms

During the past few decades, biofilm formation by a variety of microbial strains has attracted much attention, mainly in the medical and industrial settings due to their high resistance to antibiotics. However, environmental scientists and biochemical engineers have realized the importance of biofilm growth dynamics and their biocatalytic activity. For instance, the ability to forecast and control microbial communities has led to enhance biogas production and a better characterization of biofilm importance in wastewater treatment systems. Thus, understanding the fundamental processes contributing to biofilm growth is useful to anyone involved with natural or industrial settings where biofilms may play a significant role in determining variables such as bulk water quality, toxic compound biodegradation or product quality. Investigation of individual microcolonies within a biofilm using powerful microscopic tools has fueled the creation of biofilm models that reproduce biofilm growth dynamics and interactions. Mathematical frameworks that describe heterogeneous bacterial biofilms formation have greatly contributed to our understanding of physiochemical and biological principles of biofilm spreading dynamics. A clear understanding of heterogeneities at the local scale may be vital to solving the riddle of the complex nature of microbial communities, which is crucial to improve the performance, robustness and stability of biofilm-associated bioprocess