Biologically active Phytophthora mating hormone prepared by catalytic asymmetric total synthesis

A Phytophthora mating hormone with an array of 1,5-stereogenic centers has been synthesized by using our recently developed methodology of catalytic enantioselective conjugate addition of Grignard reagents. We applied this methodology in a diastereo- and enantioselective iterative route and obtained two of the 16 possible stereoisomers of Phytophthora hormone α1. These synthetic stereoisomers induced the formation of sexual spores (oospores) in A2 mating type strains of three heterothallic Phytophthora species, P. infestans, P. capsici, and P. nicotianae but not in A1 mating type strains. The response was concentration-dependent, and the oospores were viable. These results demonstrate that the biological activity of the synthetic hormone resembles that of the natural hormone α1. Mating hormones are essential components in the sexual life cycle of a variety of organisms. For plant pathogens like Phytophthora, sexual reproduction is important as a source of genetic variation. Moreover, the thick-walled oospores are the most durable propagules that can survive harsh environmental conditions. Sexual reproduction can thus greatly affect disease epidemics. The availability of synthetic compounds mimicking the activity of Phytophthora mating hormone will be instrumental for further unravelling sexual reproduction in this important group of plant pathogens.

Large Scale Bacterial Colony Screening of Diversified FRET Biosensors

Biosensors based on Forster Resonance Energy Transfer (FRET) between fluorescent protein mutants have started to revolutionize physiology and biochemistry. However, many types of FRET biosensors show relatively small FRET changes, making measurements with these probes challenging when used under sub-optimal experimental conditions. Thus, a major effort in the field currently lies in designing new optimization strategies for these types of sensors. Here we describe procedures for optimizing FRET changes by large scale screening of mutant biosensor libraries in bacterial colonies. We describe optimization of biosensor expression, permeabilization of bacteria, software tools for analysis, and screening conditions. The procedures reported here may help in improving FRET changes in multiple suitable classes of biosensors

Screen-Printed Composite LiFePO4-LLZO Cathodes Towards Solid-State Li-ion Batteries

LiFePO4(LFP) is widely used as cathode material for its low cost, high safety, and good thermal properties. It is one of the most exploited cathode materials for commercial Li-ion batteries (LIBs). Herein, we present a screen-printing method to prepare a LFP composite cathode, and a rational combination of the typical composite solid electrolytes (CSE) consisting of polyethylene oxide (PEO)/Li-salt (LiTFSi) electrolyte with ceramic filler (LLZO or Li6.4La3Zr1.4Ta0.6O12 (LLZTO)) has been successfully demonstrated for SSB. The prepared CSE offers: i) a promising ionic conductivity (0.425 mS cm(-1) at 60(degrees)C), ii) a wide electrochemical window (>4.6 V), iii) a high Li-ion transference number (tLi(+)=0.44), iv) a good interfacial compatibility with the electrode, v) a good thermal stability, and vi) a high chemical stability toward Li metal anode. The Li/CSE/Li symmetric cells can be cycled for more than 1000 h without Li-dendrites growth at a current density of 0.2 mA cm(-2). The final cell screen-printed LFP composite cathode (LFP+LLZO)//Li metal displays a high reversible specific capacity of 140 mAh g(-1) (0.1 C) and 50 mAh g(-1) (0.5 C) after 1(st) and 500th cycles

High-Throughput Platform for Optoacoustic Probing of Genetically Encoded Calcium Ion Indicators

Functional optoacoustic (OA) imaging assisted with genetically encoded calcium ion indicators (GECIs) holds promise for imaging large-scale neuronal activity at depths and spatiotemporal resolutions not attainable with existing optical microscopic techniques. However, currently available GECIs optimized for fluorescence (FL) imaging lack sufficient contrast for OA imaging and respond at wavelengths having limited penetration into the mammalian brain. Here we present an imaging platform capable of rapid assessment and cross-validation between OA and FL responses of sensor proteins expressed in Escherichia coli colonies. The screening system features optimized pulsed light excitation combined with ultrasensitive ultrasound detection to mitigate photobleaching while further allowing the dynamic characterization of calcium ion responses with millisecond precision. Targeted probing of up to six individual colonies per second in both calcium-loaded and calcium-unloaded states was possible with the system. The new platform greatly facilitates optimization of absorption-based labels, thus setting the stage for directed evolution of OA GECIs

Biotechnological production of γ-decalactone, a peach like aroma, by Yarrowia lipolytica

The request for new flavourings increases every year. Consumer perception that everything natural is better is causing an increase demand for natural aroma additives. Biotechnology has become a way to get natural products. γ-Decalactone is a peach-like aroma widely used in dairy products, beverages and others food industries. In more recent years, more and more studies and industrial processes were endorsed to cost-effect this compound production. One of the best-known methods to produce -decalactone is from ricinoleic acid catalyzed by Yarrowia lipolytica, a generally regarded as safe status yeast. As yet, several factors affecting -decalactone production remain to be fully understood and optimized. In this review, we focus on the aromatic compound -decalactone and its production by Y. lipolytica. The metabolic pathway of lactone production and degradation are addressed. Critical analysis of novel strategies of bioprocess engineering, metabolic and genetic engineering and other strategies for the enhancement of the aroma productivity are presented.This study was supported 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)

Crystal Plasticity and Fresh Lobster

Mechanics of few crystals Mechanics of many crystals 3D electron microscopy Chitin-composite

Tests of cosmic ray radiography for power industry applications

In this report, we assess muon multiple scattering tomography as a non-destructive inspection technique in several typical areas of interest to the nuclear power industry, including monitoring concrete degradation, gate valve conditions, and pipe wall thickness. This work is motivated by the need for radiographic methods that do not require the licensing, training, and safety controls of x-rays, and by the need to be able to penetrate considerable overburden to examine internal details of components that are otherwise inaccessible, with minimum impact on industrial operations. In some scenarios, we find that muon tomography may be an attractive alternative to more typical measurements.Comment: LA-UR-15-2212

The structure of basal body inner junctions from Tetrahymena revealed by electron cryo-tomography

The cilium is a microtubule-based eukaryotic organelle critical for many cellular functions. Its assembly initiates at a basal body and continues as an axoneme that projects out of the cell to form a functional cilium. This assembly process is tightly regulated. However, our knowledge of the molecular architecture and the mechanism of assembly is limited. By applying cryo-electron tomography, we obtained structures of the inner junction in three regions of the cilium from Tetrahymena: the proximal, the central core of the basal body, and the axoneme. We identified several protein components in the basal body. While a few proteins are distributed throughout the entire length of the organelle, many are restricted to specific regions, forming intricate local interaction networks in the inner junction and bolstering local structural stability. By examining the inner junction in a POC1 knockout mutant, we found the triplet microtubule was destabilized, resulting in a defective structure. Surprisingly, several axoneme-specific components were found to "infiltrate" into the mutant basal body. Our findings provide molecular insight into cilium assembly at the inner junctions, underscoring its precise spatial regulation

The Microtubule-Targeting Agent Pretubulysin Impairs the Inflammatory Response in Endothelial Cells by a JNK-Dependent Deregulation of the Histone Acetyltransferase Brd4

The anti-inflammatory effects of depolymerizing microtubule-targeting agents on leukocytes are known for a long time, but the potential involvement of the vascular endothelium and the underlying mechanistic basis is still largely unclear. Using the recently synthesized depolymerizing microtubule-targeting agent pretubulysin, we investigated the antiinflammatory potential of pretubulysin and other microtubule-targeting agents with respect to the TNF-induced leukocyte adhesion cascade in endothelial cells, to improve our understanding of the underlying biomolecular background. We found that treatment with pretubulysin reduces inflammation in vivo and in vitro via inhibition of the TNF-induced adhesion of leukocytes to the vascular endothelium by down-regulation of the pro-inflammatory cell adhesion molecules ICAM-1 and VCAM-1 in a JNK-dependent manner. The underlying mechanism includes JNK-induced deregulation and degradation of the histone acetyltransferase Bromodomaincontaining protein 4. This study shows that depolymerizing microtubule-targeting agents, in addition to their established effects on leukocytes, also significantly decrease the inflammatory activation of vascular endothelial cells. These effects are not based on altered pro-inflammatory signaling cascades, but require deregulation of the capability of cells to enter constructive transcription for some genes, setting a baseline for further research on the prominent antiinflammatory effects of depolymerizing microtubule-targeting agents

ECG, clinical and novel CT-imaging predictors of necessary pacemaker implantation after transfemoral aortic valve replacement

Purpose Newly onset conduction disturbances with the need for permanent pacemaker (PPM) implantation remain the most common complication of transcatheter aortic valve replacement (TAVR). The objective was to evaluate the predictive value of clinical, ECG and new pre-procedural CT-imaging parameters for the requirement of PPM-implantation after TAVR. Methods 2105 consecutive patients receiving TAVR using a balloon expandable prosthesis (Sapien 3, Edwards Lifesciences, Irving, CA, USA) at our institution were enrolled. Patients receiving a valve-in-valve prosthesis, TAVR after surgical repair, with missing or non-diagnostic CT-scans, with pre-implanted PPM and after TAVR in mitral position were excluded. The most suitable classification model for the given dataset was first identified through benchmark testing and later applied for prediction analysis. Results 312 eligible patients requiring PPM implantation were compared to an age- matched control group of 305 patients not requiring PPM implantation. A scaled LASSO model allowed for most accurate prediction with an AUC of 0.70. Right bundle branch block was the strongest predictor (OR 2.739), followed by atrioventricular block 1° (OR 2.091), prosthesis diameter (OR 1.351), atrial fibrillation (OR 1.255), arterial hypertension (OR 1.215), coronary artery disease (1.070), the angle of ventricle axis and aortic root (OR 1.030), sinotubular junction height (OR 1.014) and the calcification of the left coronary cuspid (OR 1.007). Conclusions ECG- and clinical outperform imaging parameters in predicting PPM-implantation following TAVR. Right bundle branch block emerged as the most significant predictor overall, while the angle of ventricle axis and aortic root as a novel imaging-based predictor