Magnetosome Gene Duplication as an Important Driver in the Evolution of Magnetotaxis in the Alphaproteobacteria

The evolution of microbial magnetoreception (or magnetotaxis) is of great interest in the fields of microbiology, evolutionary biology, biophysics, geomicrobiology, and geochemistry. Current genomic data from magnetotactic bacteria (MTB), the only prokaryotes known to be capable of sensing the Earth’s geomagnetic field, suggests an ancient origin of magnetotaxis in the domain Bacteria. Vertical inheritance, followed by multiple independent magnetosome gene cluster loss, is considered to be one of the major forces that drove the evolution of magnetotaxis at or above the class or phylum level, although the evolutionary trajectories at lower taxonomic ranks (e.g., within the class level) remain largely unstudied. Here we report the isolation, cultivation, and sequencing of a novel magnetotactic spirillum belonging to the genus Terasakiella (Terasakiella sp. strain SH-1) within the class Alphaproteobacteria. The complete genome sequence of Terasakiella sp. strain SH-1 revealed an unexpected duplication event of magnetosome genes within the mamAB operon, a group of genes essential for magnetosome biomineralization and magnetotaxis. Intriguingly, further comparative genomic analysis suggests that the duplication of mamAB genes is a common feature in the genomes of alphaproteobacterial MTB. Taken together, with the additional finding that gene duplication appears to have also occurred in some magnetotactic members of the Deltaproteobacteria, our results indicate that gene duplication plays an important role in the evolution of magnetotaxis in the Alphaproteobacteria and perhaps the domain Bacteria

Erratum: A multi-objective optimization-based layer-by-layer blade-coating approach for organic solar cells: Rational control of vertical stratification for high performance (Energy and Environmental Science (2019) 12 (3118-3132) DOI: 10.1039/C9EE02295C)

The Acknowledgements section should have included the following sentence: "This work was performed in part on the SAXS/ WAXS beamline at the Australian Synchrotron, part of ANSTO". The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers

A multi-objective optimization-based layer-by-layer blade-coating approach for organic solar cells:Rational control of vertical stratification for high performance

A major breakthrough in organic solar cells (OSCs) in the last thirty years was the development of the bulk heterojunction (BHJ) solution processing strategy, which effectively provided a nanoscale phase-separated morphology, aiding in the separation of Coulombically bound excitons and facilitating charge transport and extraction. Compared with the application of the layer-by-layer (LbL) approach proposed in the same period, the BHJ spin-coating technology shows overwhelming advantages for evaluating the performance of photovoltaic materials and achieving more-efficient photoelectric conversion. Thus, in this study, we have further compared the BHJ and LbL processing strategies via the doctor-blade coating technology because it is a roll-to-roll compatible high-throughput thin film fabrication route. We systematically evaluated multiple target parameters, including morphological characteristics, optical simulation, physical kinetics, device efficiency, and blend stability issues. It is worth emphasizing that our findings disprove the old stereotypes such as the BHJ processing method is superior to the LbL technology for the preparation of high-performance OSCs and the LbL approach requires an orthogonal solvent and donor/acceptor materials with special solubility. Our studies demonstrate that the LbL blade-coating approach is a promising strategy to effectively reduce the efficiency-stability gap of OSCs and even a superior alternative to the BHJ method in commercial applications

Prostaglandin signalling regulates ciliogenesis by modulating intraflagellar transport

Cilia are microtubule-based organelles that mediate signal transduction in a variety of tissues. Despite their importance, the signalling cascades that regulate cilium formation remain incompletely understood. Here we report that prostaglandin signalling affects ciliogenesis by regulating anterograde intraflagellar transport (IFT). Zebrafish leakytail (lkt) mutants show ciliogenesis defects, and the lkt locus encodes an ATP-binding cassette transporter (ABCC4). We show that Lkt/ABCC4 localizes to the cell membrane and exports prostaglandin E2 (PGE2), a function that is abrogated by the Lkt/ABCC4T804M mutant. PGE2 synthesis enzyme cyclooxygenase-1 and its receptor, EP4, which localizes to the cilium and activates the cyclic-AMP-mediated signalling cascade, are required for cilium formation and elongation. Importantly, PGE2 signalling increases anterograde but not retrograde velocity of IFT and promotes ciliogenesis in mammalian cells. These findings lead us to propose that Lkt/ABCC4-mediated PGE2 signalling acts through a ciliary G-protein-coupled receptor, EP4, to upregulate cAMP synthesis and increase anterograde IFT, thereby promoting ciliogenesis

Friction Control Of One-Dimensional Particles With Morse-Type Interaction

In this paper, the Morse-type FK model is applied to the study of friction control required in many fields. Based on the Morse-type FK model, a feedback tracking control law using limited accessible elements is designed to realize an accurate tracking whose objective is to make the average system reach a designated velocity. In addition, the motion properties of each single particle are analyzed. Simulation results show satisfactory performances. © 2011 IEEE

A Patient with a Right Atrium Mass and Congenital Heart Disease: A Challenging Diagnosis of a Stubborn Disease

Cardiac lymphoma is extremely rare. An intracardiac mass has rarely been reported to be the cardiac involvement of extranodal lymphoma. It is difficult to establish a final diagnosis via routine examinations. The ability of an echocardiogram to characterize tissue is limited; systemic (18)F-FDG PET/CT scans provide important information for both staging and response assessment in patients with lymphoma. A 68-year-old Chinese male with a second patent foramen ovale (PFO) and an interventricular septal defect presented at our institute with persistent fever, shortness of breath, repeated paroxysmal supraventricular tachycardia (PSVT) attack, and rapidly progressing superior vena cava syndrome. The patient also presented with a mass located in the upper right atrium and superior vena cava which was detected by echocardiogram. (18)F-FDG PET/CT scan revealed a pathological increase of (18)F-FDG uptake in the atrial mass and several other extracardiac lymph nodes. Lymph node biopsy was positive for large B-cell lymphoma. Immunohistochemistry revealed intense and diffuse expression of CD20, CD10, BCL-6, and Ki-67. The patient died without any chemotherapy 18 days after hospital discharge

Nonlinear Control And Synchronization Of A Class Of Nonlinear Coupled Dynamical Systems

In this paper, a control problem for a class of nonlinear coupled dynamical systems is proposed and a continuous nonlinear feedback control law is designed using direct Lyapunov method to solve the proposed control problem. Moreover, synchronization problem for a special case of this class nonlinear coupled dynamical systems is concerned. Numerical examples show the effectiveness and advantage of the designed continuous nonlinear control law and derived synchronization result. © 2013 South China University of Technology, Academy of Mathematics and Systems Science, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg

Genomic analysis of a pure culture of magnetotactic bacterium Terasakiella sp. SH-1

International audienceMagnetotactic bacteria (MTB) display magnetotaxis ability because of biomineralization of intracellular nanometer-sized, membrane-bound organelles termed magnetosomes. Despite having been discovered more than half a century, only a few representatives of MTB have been isolated and cultured in the laboratory. In this study, we report the genomic characterization of a novel marine magnetotactic spirillum strain SH-1 belonging to the genus Terasakiella that was recently isolated. A gene encoding haloalkane dehalogenase, which is involved in the degradation of chlorocyclohexane, chlorobenzene, chloroalkane and chloroalkene, was identified. SH-1 genome contained cysCHI and soxBAZYX genes, thus potentially capable of assimilatory sulfate reduction to H2S and using thiosulfate as electron donors and oxidizing it to sulfate. Genome of SH-1 also contained genes encoding periplasmic dissimilatory nitrate reductases (napAB), assimilatory nitrate reductase (nasA) and assimilatory nitrite reductases (nasB), suggesting that it is capable of gaining energy by converting nitrate to ammonia. The pure culture of Terasakiella sp. SH-1 together with its genomic results offers new opportunities to examine biology, physiology and biomineralization mechanisms of MTB

A species of magnetotactic deltaproteobacterium was detected at the highest abundance during an algal bloom

International audienceMagnetotactic bacteria (MTB) are a group of microorganisms that have the ability to synthesize intracellular magnetic crystals (magnetosomes). They prefer microaerobic or anaerobic aquatic sediments. Thus, there is growing interest in their ecological roles in various habitats. In this study we found co-occurrence of a large rod-shaped deltaproteobacterial magnetotactic bacterium (tentatively named LR-1) in the sediment of a Downloaded from https://academic.oup.com/femsle/advance-article-abstract/doi/10.1093/femsle/fnz253/5681391 by guest on 23 December 201

Primary cardiac diffuse large B-cell lymphoma with concurrent high MYC and BCL2 expression in an immunocompetent Chinese elderly woman

Primary cardiac lymphoma is a rare type of extranodal lymphoma that involves only heart and/or pericardium. It is usually observed in immunodeficient people. However, immunocompetent patients may also suffer from this disease. Most primary cardiac lymphomas are of B-cell lineage, and they usually present as diffuse large B-cell lymphoma (DLBCL). Diffuse large B-cell lymphoma with concurrently high MYC and BCL2 expression, which is named as double-expressor lymphoma (DEL), is a rare subtype of DLBCL. Herewe report a rare case of a primary cardiac DEL in an immunocompetent 65-year old Chinese woman. Echocardiography and magnetic resonance imaging revealed a mass of 6.6 cmx5.6 cm in the right atrium. No tumor formations were observed in other organs. Histopathologic examination showed that the cardiac tumor was diffuse large B-cell lymphoma, nongerminal center B-cell type by Hans algorithm. The tumor cells showed high MYC and BCL2 protein expression by immunohistochemistry, with high proliferative index. (C) 2017 Elsevier Inc. All rights reserved