Predominance of deterministic microbial community dynamics in salterns exposed to different light intensities

While the dynamics of microbial community assembly driven by environmental perturbations have been extensively studied, our understanding is far from complete, particularly for light-induced perturbations. Extremely halophilic communities thriving in coastal solar salterns are mainly influenced by two environmental factors—salt concentrations and high sunlight irradiation. By experimentally manipulating light intensity through the application of shading, we showed that light acts as a deterministic factor that ultimately drives the establishment of recurrent microbial communities under near-saturation salt concentrations. In particular, the stable and highly change-resistant communities that established under high-light intensities were dominated (>90% of metagenomic reads) by Haloquadratum spp. and Salinibacter spp. On the other hand, under 37-fold lower light intensity, different, less stable and change-resistant communities were established, mainly dominated by yet unclassified haloarchaea and relatively diverse photosynthetic microorganisms. These communities harboured, in general, much lower carotenoid pigment content than their high-irradiation counterparts. Both assemblage types appeared to be highly resilient, re-establishing when favourable conditions returned after perturbation (i.e. high-irradiation for the former communities and low-irradiation for the latter ones). Overall, our results revealed that stochastic processes were of limited significance to explain these patterns.     

The Ubiquitin-associated (UBA) 1 Domain of Schizosaccharomyces pombe Rhp23 Is Essential for the Recognition of Ubiquitin-proteasome System Substrates Both in Vitro and in Vivo

The ubiquitin-proteasome system is essential for maintaining a functional cell. Not only does it remove incorrectly folded proteins, it also regulates protein levels to ensure their appropriate spatial and temporal distribution. Proteins marked for degradation by the addition of Lys⁴⁸-linked ubiquitin (Ub) chains are recognized by shuttle factors and transported to the 26 S proteasome. One of these shuttle factors, Schizosaccharomyces pombe Rhp23, has an unusual domain architecture. It comprises an N-terminal ubiquitin-like domain that can recognize the proteasome followed by two ubiquitin-associated (UBA) domains, termed UBA1 and UBA2, which can bind Ub. This architecture is conserved up to humans, suggesting that both domains are important for Rhp23 function. Such an extent of conservation raises the question as to why, in contrast to all other shuttle proteins, does Rhp23 require two UBA domains? We performed in vitro Ub binding assays using domain swap chimeric proteins and mutated domains in isolation as well as in the context of the full-length protein to reveal that the Ub binding properties of the UBA domains are context-dependent. In vivo, the internal Rhp23 UBA1 domain provides sufficient Ub recognition for the protein to function without UBA2.     

Assessment of Low-Frequency Magnetic Fields Emitted by DC Fast Charging Columns

The expected imminent widespread use of electromobility in transport systems draws attention to the possible effects of human exposure to magnetic fields generated inside electric vehicles and during their recharge. The current trend is to increase the capacity of the battery inside the vehicles to extend the available driving range and to increase the power of recharging columns to reduce the time required for a full recharge. This leads to higher currents and potentially stronger magnetic fields. The Interoperability Center of the Joint Research Center started an experimental activity focused on the assessment of low-frequency magnetic fields emitted by five fast-charging devices available on the market in recharge and standby conditions. The aim of this study was to contribute to the development of a standard measurement procedure for the assessment of magnetic fields emitted by direct current charging columns. The spectrum and amplitudes of the magnetic field, as well as exposure indices according to guidelines for the general public and occupational exposure, were recorded by means of a magnetic field probe analyzer. The worst-case scenario for instantaneous physical direct and indirect effects was identified. Measurements within the frequency range of 25 Hz–2 kHz revealed localized magnetic flux density peaks above 100 μT at the 50 Hz frequency in three out of five chargers, registered in close proximity during the recharge. Beyond this distance, exposure indices were recorded showing values below 50% of reference levels. Bioelectromagnetics. 2020;41:308–317 © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.     

Primary retroperitoneal mucinous cystadenoma of borderline malignancy in a male patient. Case report and review of the literature

The spleen is an infrequent site for metastatic lesions, and solitary splenic metastases from squamous cell carcinoma of the esophagus are very rare: only 4 cases have been reported thus far. These lesions are whitish nodules that are macroscopically and radiologically similar to primary splenic lymphomas. We report a case of metachronous splenic metastases from esophageal cancer and multiple splenic abscesses, which developed nine months after apparently curative esophagectomy without adjuvant chemotherapy. The patient underwent splenectomy dissection followed by adjuvant chemotherapy, but liver and skin metastases developed, and the patient died 9 months later.     

Complete genome sequence of Kribbella flavida type strain (IFO 14399)

The genus Kribbella consists of 15 species, with Kribbella flavida (Park et al. 1999) as the type species. The name Kribbella was formed from the acronym of the Korea Research Institute of Bioscience and Biotechnology, KRIBB. Strains of the various Kribbella species were originally isolated from soil, potato, alum slate mine, patinas of catacombs or from horse racecourses. Here we describe the features of K. flavida together with the complete genome sequence and annotation. In addition to the 5.3 Mbp genome of Nocardioides sp. JS614, this is only the second completed genome sequence of the family Nocardioidaceae. The 7,579,488 bp long genome with its 7,086 protein-coding and 60 RNA genes and is part of the Genomic Encyclopedia of Bacteria and Archaea project.