Genome-Resolved Proteomic Stable Isotope Probing of Soil Microbial Communities Using 13CO2 and 13C-Methanol.

Stable isotope probing (SIP) enables tracking the nutrient flows from isotopically labeled substrates to specific microorganisms in microbial communities. In proteomic SIP, labeled proteins synthesized by the microbial consumers of labeled substrates are identified with a shotgun proteomics approach. Here, proteomic SIP was combined with targeted metagenomic binning to reconstruct metagenome-assembled genomes (MAGs) of the microorganisms producing labeled proteins. This approach was used to track carbon flows from 13CO2 to the rhizosphere communities of Zea mays, Triticum aestivum, and Arabidopsis thaliana. Rhizosphere microorganisms that assimilated plant-derived 13C were capable of metabolic and signaling interactions with their plant hosts, as shown by their MAGs containing genes for phytohormone modulation, quorum sensing, and transport and metabolism of nutrients typical of those found in root exudates. XoxF-type methanol dehydrogenases were among the most abundant proteins identified in the rhizosphere metaproteomes. 13C-methanol proteomic SIP was used to test the hypothesis that XoxF was used to metabolize and assimilate methanol in the rhizosphere. We detected 7 13C-labeled XoxF proteins and identified methylotrophic pathways in the MAGs of 8 13C-labeled microorganisms, which supported the hypothesis. These two studies demonstrated the capability of proteomic SIP for functional characterization of active microorganisms in complex microbial communities

Community proteogenomics reveals the systemic impact of phosphorus availability on microbial functions in tropical soil.

Phosphorus is a scarce nutrient in many tropical ecosystems, yet how soil microbial communities cope with growth-limiting phosphorus deficiency at the gene and protein levels remains unknown. Here, we report a metagenomic and metaproteomic comparison of microbial communities in phosphorus-deficient and phosphorus-rich soils in a 17-year fertilization experiment in a tropical forest. The large-scale proteogenomics analyses provided extensive coverage of many microbial functions and taxa in the complex soil communities. A greater than fourfold increase in the gene abundance of 3-phytase was the strongest response of soil communities to phosphorus deficiency. Phytase catalyses the release of phosphate from phytate, the most recalcitrant phosphorus-containing compound in soil organic matter. Genes and proteins for the degradation of phosphorus-containing nucleic acids and phospholipids, as well as the decomposition of labile carbon and nitrogen, were also enhanced in the phosphorus-deficient soils. In contrast, microbial communities in the phosphorus-rich soils showed increased gene abundances for the degradation of recalcitrant aromatic compounds, transformation of nitrogenous compounds and assimilation of sulfur. Overall, these results demonstrate the adaptive allocation of genes and proteins in soil microbial communities in response to shifting nutrient constraints

Extensive Crosstalk between O-GlcNAcylation and Phosphorylation Regulates Akt Signaling

O-linked N-acetylglucosamine glycosylations (O-GlcNAc) and O-linked phosphorylations (O-phosphate), as two important types of post-translational modifications, often occur on the same protein and bear a reciprocal relationship. In addition to the well documented phosphorylations that control Akt activity, Akt also undergoes O-GlcNAcylation, but the interplay between these two modifications and the biological significance remain unclear, largely due to the technique challenges. Here, we applied a two-step analytic approach composed of the O-GlcNAc immunoenrichment and subsequent O-phosphate immunodetection. Such an easy method enabled us to visualize endogenous glycosylated and phosphorylated Akt subpopulations in parallel and observed the inhibitory effect of Akt O-GlcNAcylations on its phosphorylation. Further studies utilizing mass spectrometry and mutagenesis approaches showed that O-GlcNAcylations at Thr 305 and Thr 312 inhibited Akt phosphorylation at Thr 308 via disrupting the interaction between Akt and PDK1. The impaired Akt activation in turn resulted in the compromised biological functions of Akt, as evidenced by suppressed cell proliferation and migration capabilities. Together, this study revealed an extensive crosstalk between O-GlcNAcylations and phosphorylations of Akt and demonstrated O-GlcNAcylation as a new regulatory modification for Akt signaling

A lactoglobulin-composite self-healing coating for Mg alloys.

Corrosion issue is one of the most crucial bottlenecks for extensive employment of Mg alloys, in particular under harsh engineering conditions. Differing from traditional approaches, a self-healing protective coating composed of lactoglobulin is proposed herein to offer sustainable protection to the underlying Mg parts. Corrosion resistance, evaluated by electrochemical measurements and hydrogen evolution tests, indicates that the lactoglobulin composite film exhibits nobler corrosion potential (−1.28 VSCE), smaller corrosion current density (8.4 × 10−6 A/cm2), and lower average corrosion rate (~0.03 mm/y) than those of its bare counterparts. Moreover, the pre-made cracks in the film were evidently self-healed within 24h of exposure to corrosive media. The proposed self-healing lactoglobulin composite film provides opportunities to tackle the corrosion challenges of Mg alloys

Seismic image enhancement by double-weighted stacking

Normal-moveout velocity analysis using semblance spectrum and common-midpoint stacking after normal-moveout correction are two indispensable procedures in seismic reflection data processing, especially for random noise attenuation, velocity model estimation, and imaging quality enhancement. During this process, weighting functions have been frequently used to improve the resolution of semblance and the performance of stacking. In this paper, the interactive relationship between semblance and stacking allows a new method of double-weighted stacking to be created. This method applies the same local-similarity-weighting function to the calculation of both semblance and stacking, aiming to enhance the final stacked image sections. The synthetic and field data numerical experiments have demonstrated that our new approach enhances the signal-to-noise ratio and the reflection-event continuity compared with conventional processing flows

High-yield solar-driven atmospheric water harvesting with ultra-high salt content composites encapsulated in porous membrane

Sorption-based atmospheric water harvesting (SAWH) is recognized as a feasible and sustainable approach to address global water scarcity in arid regions. However, easy-to-prepare and inexpensive salt-based sorbents have stringent requirements referring to sorption duration and environmental humidityotherwise, the leakage of salt solution can occur. Here, we develop a composite sorbent with remarkably high salt content of 80 wt % and without the risk of leakage by introducing a polytetrafluoroethylene membrane encapsulation method. The developed composite HSCC-E10 shows both fast sorption kinetics inherent to the matrix of composites and high absorption capacity of hygroscopic salt solutions, achieving ultra-high sorption capacity of 3.75 g/g, 2.83 g/g, and 1.47 g/g for 90%, 70%, and 30% relative humidity (RH), respectively. A lab-scale device is developed demonstrating 560 mL/m2 water yield under outdoor natural sunlight. The applicability of proposed sorbents could pave the road for future middle- or large-scale applications, such as vehicle-mounted and continuous SAWH