Abstract
Plasmids can mediate horizontal gene transfer of antibiotic resistance, virulence genes, and other adaptive factors across bacterial populations. Here, we analyze genomic composition and ...pairwise sequence identity for over 10,000 reference plasmids to obtain a global map of the prokaryotic plasmidome. Plasmids in this map organize into discrete clusters, which we call plasmid taxonomic units (PTUs), with high average nucleotide identity between its members. We identify 83 PTUs in the order
Enterobacterales
, 28 of them corresponding to previously described archetypes. Furthermore, we develop an automated algorithm for PTU identification, and validate its performance using stochastic blockmodeling. The algorithm reveals a total of 276 PTUs in the bacterial domain. Each PTU exhibits a characteristic host distribution, organized into a six-grade scale (I–VI), ranging from plasmids restricted to a single host species (grade I) to plasmids able to colonize species from different phyla (grade VI). More than 60% of the plasmids in the global map are in groups with host ranges beyond the species barrier.
Ruthenium and TiO2 rutile stabilize Ti3+ Lewis acid sites for decarboxylative CC coupling of acids with remarkably stability in hot condensed water.
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•Liquid-phase ketonization of ...acetic acid over three catalysts of Ru on different titania supports (anatase, rutile and P25) demonstrates the outstanding effect of the support hydrophobicity on the catalyst stability.•The catalyst of Ru supported on rutile (the most hydrophobic support studied) presents the highest ketonization activity and stability.•Partially hydrophobic materials can facilitate the high temperature reactions in aqueous environments for biomass conversion, environmental remediation, artificial photosynthesis and green chemistry.
Stabilization of oxygen vacancies on metal oxides (e.g. TiO2) in liquid phase is an important challenge for the utilization of these materials in artificial photosynthesis, environmental remediation and biomass conversion. To create materials with low-energy barriers for vacancies formation and high stability in aqueous environments, we have developed partially hydrophobic (contact angle ≥90°) TiO2 rutile decorated with Ru nanoparticles. Negligible catalytic activity was observed when hydrophilic (contact angle 51°) 5wt.% Ru/TiO2 anatase was utilized in hot liquid water, while amphiphilic 5wt.% Ru/TiO2 rutile (contact angle ∼90°) retained its catalytic activity. Fine-control of crystalline structure (lattice matching) of TiO2 and Ru allowed us to accelerate the rate of reaction, while the high surface hydrophobicity of the support enabled the stabilization of Ti3+ cations in aqueous and organic environments.
HY zeolites hydrophobized by functionalization with organosilanes are much more stable in hot liquid water than the corresponding untreated zeolites. Silylation of the zeolite increases ...hydrophobicity without significantly reducing the density of acid sites. This hydrophobization with organosilanes makes the zeolites able to stabilize water/oil emulsions and catalyze reactions of importance in biofuel upgrading, i.e., alcohol dehydration and alkylation of m-cresol and 2-propanol in the liquid phase, at high temperatures. While at 200 °C the crystalline structure of an untreated HY zeolite collapses in a few hours in contact with a liquid medium, the functionalized hydrophobic zeolites keep their structure practically unaltered. Detailed XRD, SEM, HRTEM, and BET analyses indicate that even after reaction under severe conditions, the hydrophobic zeolites retain their crystallinity, surface area, microporosity, and acid density. It is proposed that by preferentially anchoring hydrophobic functionalities on the external surface, the direct contact of bulk liquid water and the zeolite is hindered, thus preventing the collapse of the framework during the reaction in liquid hot water.
•Oil/wax yields from pyrolysis of mixed plastics can be predicted to a good extent.•The presence of PET in mixed plastic favors solid formation beyond predicted values.•The model can consistently ...predict the aliphatic carbon fraction in the oil/wax product.
The predictability of pyrolysis yields and product composition of mixed plastics has been studied. To do so, pyrolysis of virgin polymers (HDPE, LDPE, PP, PS and PET) and eight individual sorting categories from a real waste DKR-350 stream (PE rigid/film, PP rigid/film, PET, PS, multilayer flexibles, and clogged materials) was performed in a batch reactor at 500 °C at laboratory scale. The obtained oil/wax, gas, and solid yields and the composition of oil/wax of those individual feedstocks were used as input of a superposition model to predict the corresponding pyrolysis yields and oil/wax composition of mixed feeds, which were later compared with the experimentally measured product yields from the pyrolysis of those mixed streams. This linear model predicts the oil/wax yield of the mixed streams to a reasonable extent, with a maximum yield deviation (overestimation) of 8 percentage points. However, the presence of significant amounts of PET (above 33 wt%) in the mixed plastic streams negatively impacts the production of the condensable product and promotes the formation of solid products beyond the expected predicted values. Quantification of the type of carbon (aliphatic, aromatic and carbonyl) present in all the oil/wax products was done using 13C NMR spectroscopy. A linear model could also predict the aliphatic carbon yield in the condensable product from plastic waste streams with high accuracy (maximum yield difference of 6 percentage points). However, the aromatic carbon yield could not be predicted, probably due to the observed behavior of PET, which interacts with other polymers to promote solid product formation.
Metal‐containing Janus particles are used as interfacial catalyst/emulsifiers that catalyze reactions in biphasic systems with controlled “phase selectivity”, that is, conversion of the desired ...reaction on one side of the emulsion. The reaction may affect the solubility of the molecule in one phase, causing migration to the opposite phase. As a result, combined reaction and separation can be achieved in a single reaction vessel.
Reductive depolymerization of lignin-containing stillage (LA lignin) from 2nd generation bioethanol industrial plants have been studied over two different families of catalysts: conventional porous ...Ru catalysts supported on ZrO2 or activated carbon, and 1-dimensional Ru catalysts supported on multi-walled carbon nanotubes (MWCNT). The lignin depolymerization degree using conventional porous catalysts resulted in values of 42 and 53%, for Ru/ZrO2 and Ru/C, respectively. Strikingly, when using 1D-supported catalysts (Ru/MWCNT and Ru/ZrO2/MWCNT), the extent of lignin depolymerization measured by 1H13C HSQC NMR, reached values of c.a. 80% of β-O-4 bond disappearance and a reduction of the average molecular weight from 3600 Da to ~ 1900 Da. The higher accessibility of the lignin agglomerates to the 1-D catalyst nanoparticles substantially improves the lignin depolymerization degree, which make this approach of great interest in the production of fine chemicals and fuel additives.
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•Lignin stillage has been depolymerized up to 80% of β-O-4 bond disappearance.•Selective depolymerization of β-O-4 ether bonds has been achieved on Ru catalysts.•1-D Ru/MWCNT catalysts show the highest depolymerization extent.•1-D Ru/MWCNT catalysts increase accessibility of the lignin molecules to the catalyst.
Inflammation is typically associated with the development of fibrosis, cirrhosis and hepatocellular carcinoma. The key role of protein tyrosine phosphatase 1B (PTP1B) in inflammatory responses has ...focused this study in understanding its implication in liver fibrosis. Here we show that hepatic PTP1B mRNA expression increased after bile duct ligation (BDL), while BDL-induced liver fibrosis was markedly reduced in mice lacking Ptpn1 (PTP1B
) as assessed by decreased collagen deposition and α-smooth muscle actin (α-SMA) expression. PTP1B
mice also showed a significant increase in mRNA levels of key markers of monocytes recruitment (Cd68, Adgre1 and Ccl2) compared to their wild-type (PTP1B
) littermates at early stages of injury after BDL. Interestingly, the lack of PTP1B strongly increased the NADPH oxidase (NOX) subunits Nox1/Nox4 ratio and downregulated Cybb expression after BDL, revealing a pro-survival pattern of NADPH oxidase induction in response to liver injury. Chimeric mice generated by transplantation of PTP1B
bone marrow (BM) into irradiated PTP1B
mice revealed similar hepatic expression profile of NOX subunits than PTP1B
mice while these animals did not show differences in infiltration of myeloid cells at 7 days post-BDL, suggesting that PTP1B deletion in other liver cells is necessary for boosting the early inflammatory response to the BDL. PTP1B
BM transplantation into PTP1B
mice also led to a blockade of TGF-β and α-SMA induction after BDL. In vitro experiments demonstrated that deficiency of PTP1B in hepatocytes protects against bile acid-induced apoptosis and abrogates hepatic stellate cells (HSC) activation, an effect ameliorated by NOX1 inhibition. In conclusion, our results have revealed that the lack of PTP1B switches NOX expression pattern in response to liver injury after BDL and reduces HSC activation and liver fibrosis.
Pyrolysis of a post-consumer plastic waste stream (DKR-350) has been performed at a laboratory scale in a fixed-bed reactor at 500 °C. DKR-350 is a complex mixture of post-consumer plastics ...comprising polyethylene, polypropylene, polystyrene, polyethylene terephthalate, clogged materials, multilayer flexibles, together with considerable amounts of biogenic and inorganic residues and halogens. The influence of different washing procedures on feedstock composition and pyrolysis product yields was investigated. Washing effectively lowers the biogenic, inorganic and halogen contents in DKR-350, though does not affect the yield of the desired oil/wax (66 to 69 wt%). 27% of the oil/wax lies in the boiling point range of naphtha and gasoline (< 200 °C). During pyrolysis, the oxygen content of the oil/wax is reduced to 8–14 wt%, compared to 10–16 wt% in the feed. Chlorine analysis revealed that most of the chlorine present in the feed is removed by washing. Nevertheless, the concentration of chlorine in the oil/wax is still high (>150 ppm), showing the presence of recalcitrant organochlorides in the feed. Thus, post-treatment is still required to upgrade it to feedstock for the production of fuels and/or chemicals.
•Pyrolysis condensable yields of ~70 wt% were obtained from a plastic waste stream.•Washing pretreatments do not affect the pyrolysis condensable yield.•A reduction of molecular weight of ~125 times (feed to condensable product) is achieved.•Chlorine concentration is reduced up to ~92% (feed to condensable product).
Traditional culture media do not resemble the metabolic composition of human blood. The concentration of different metabolites in these media influences mitochondrial biogenesis and oxidative ...phosphorylation (OXPHOS) function. This knowledge is essential for the interpretation of results obtained from cellular models used for the study of OXPHOS function.
Aphid‐borne viruses are responsible for major cucurbit diseases and hamper the sustainability of crop production. Systematic monitoring can reveal the occurrence and distribution of these viruses, in ...addition to unadvertised viruses, facilitating the control of diseases. For three consecutive (2018–2020) seasons, the presence of aphid‐borne viruses was monitored from a total of 292 samples of watermelon and squash plants that showed yellowing symptoms in three major cucurbit‐producing areas (Castilla La‐Mancha, Alicante, and Murcia) in Spain. We observed that cucurbit aphid‐borne yellows virus (CABYV) was the most common virus found (29%) in the plants from both crops. Likewise, except for squash samples from Castilla La‐Mancha and Alicante, watermelon mosaic virus (WMV) was also found (23%) with a relatively high frequency. Furthermore, we observed the exacerbation of bright yellowing symptoms in watermelon plants that was often accompanied by considerable fruit abortion. CABYV was the only causative agent for this new yellowing disease, and two infectious cDNA clones (one from watermelon, CABYV‐LP63, and another from melon, CABYV‐MEC12.1) were constructed to further compare and characterize this CABYV disease. Based on the full‐length genome, both isolates were grouped phylogenetically together within the Mediterranean clade. However, the Koch's postulates tests were only successfully completed for the LP63 isolate, which also showed several amino acid changes and two potential recombination events, as compared to MEC12.1. Remarkably, the LP63 isolate caused more severe symptoms and showed higher RNA accumulation than MEC12.1 in five cucurbit plant species. These results suggest that a novel CABYV variant that causes severe yellowing symptoms may be causing outbreaks in cucurbit crops.
CABYV and WMV are two prevalent viruses affecting watermelon and squash crops in Spain, and there is a need to study the genetic diversity of CABYV populations, whereas a novel CABYV variant may be potentially threating cucurbit crops.
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