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1.
Chemosphere ; 356: 141853, 2024 May.
Article in English | MEDLINE | ID: mdl-38582161

ABSTRACT

Ceftazidime (CAZ) is an emerging organic pollutant with a long-lasting presence in the environment. Although some PbO2 materials exhibit degradation capabilities, inefficient electron transport in the substrate layer and the problem of electrode stability still limit their use. Here, an interfacial design in which TiO2 nanotube arrays generate Ti3+ self-doping oxide substrate layers and highly active 3D Sb-SnO2 nanoflowers-like interlayers was used to prepare PbO2 anodes for efficient degradation of CAZ. Interestingly, after implementing Ti3+ self-doping in the PbO2 anode base layer and introducing 3D nanoflowers-like structures, the capacity for •OH generation increased significantly. The modified electrode exhibited 5-fold greater •OH generation capacity compared to the unmodified electrode, and a 2.7-fold longer accelerated electrode lifetime. The results indicate that interfacial engineering of the base and intermediate layers of the electrodes can improve the electron transfer efficiency, promote the formation of •OH, and extend the anode lifetime of the activated CAZ system.


Subject(s)
Electrodes , Lead , Nanotubes , Tin Compounds , Titanium , Titanium/chemistry , Nanotubes/chemistry , Tin Compounds/chemistry , Lead/chemistry , Oxides/chemistry , Antimony/chemistry , Electrochemical Techniques/methods , Water Pollutants, Chemical/chemistry
3.
Environ Sci Technol ; 58(9): 4428-4437, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38400916

ABSTRACT

The adsorption and activation of pollutant molecules and oxygen play a critical role in the oxidation reaction of volatile organic compounds (VOCs). In this study, superior adsorption and activation ability was achieved by modulating the interaction between Pt nanoparticles (NPs) and UiO-66 (U6) through the spatial position effect. Pt@U6 exhibits excellent activity in toluene, acetone, propane, and aldehyde oxidation reactions. Spectroscopic studies, 16O2/18O2 kinetic isotopic experiments, and density functional theory (DFT) results jointly reveal that the encapsulated Pt NPs of Pt@U6 possess higher electron density and d-band center, which is conducive for the adsorption and dissociation of oxygen. The toluene oxidation reaction and DFT results indicate that Pt@U6 is more favorable to activate the C-H of toluene and the C═C of maleic anhydride, while Pt/U6 with lower electron density and d-band center exhibits a higher oxygen dissociation temperature and higher reactant activation energy barriers. This study provides a deep insight into the architecture-performance relation of Pt-based catalysts for the catalytic oxidation of VOCs.


Subject(s)
Metal-Organic Frameworks , Nanoparticles , Phthalic Acids , Volatile Organic Compounds , Volatile Organic Compounds/chemistry , Toluene/chemistry , Oxygen
4.
Environ Sci Technol ; 58(4): 2153-2161, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38244211

ABSTRACT

Nitrous oxide (N2O) has a detrimental impact on the greenhouse effect, and its efficient catalytic decomposition at low temperatures remains challenging. Herein, the cobalt-based high-entropy oxide with a spinel-type structure (Co-HEO) is successfully fabricated via a facile coprecipitation method for N2O catalytic decomposition. The obtained Co-HEO catalyst displays more remarkable catalytic performance and higher thermal stability compared with single and binary Co-based oxides, as the temperature of 90% N2O decomposition (T90) is 356 °C. A series of characterization results reveal that the synergistic effect of multiple elements enhances the reducibility and augments oxygen vacancy in the high-entropy system, thus boosting the activity of the Co-HEO catalyst. Moreover, density functional theory (DFT) calculations and the temperature-programmed surface reaction (TPSR) with isotope labeling demonstrate that N2O decomposition on the Co-HEO catalyst follows the Langmuir-Hinshelwood (L-H) mechanism with the promotion of abundant oxygen vacancies. This work provides a fundamental understanding of the synergistic catalytic effect in N2O decomposition and paves the way for the novel environmental catalytic applications of HEO.


Subject(s)
Cobalt , Oxides , Entropy , Oxides/chemistry , Cobalt/chemistry , Oxygen
5.
Clin Rheumatol ; 43(3): 1073-1082, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38206544

ABSTRACT

OBJECTIVE: To assess the long-term safety and efficacy of umbilical cord mesenchymal stem cells transplantation (UMSCT) in patients with systemic sclerosis (SSc). METHODS: Forty-one patients with moderate to severe SSc underwent UMSCT at the Affiliated Drum Tower Hospital of Nanjing University Medical School from 2009 to 2017. In this study, we conducted a longitudinal and retrospective analysis and compared the clinical and laboratory manifestations before and after UMSCT. The main outcome of the study was overall survival. We evaluated changes in the modified Rodnan Skin Score (mRSS), as well as the changes in the pulmonary examination by using high-resolution computed tomography (HRCT) and ultrasound cardiogram (UCG). Additionally, we assessed the Health Assessment Questionnaire-Disability Index (HAQ-DI) and the severity of peripheral vascular involvement during the first year after treatment. RESULTS: The overall 5-year survival rate was 92.7% (38 out of 41 patients). Following UMSCT, the mean mRSS significantly decreased from 18.68 (SD = 7.26, n = 41) at baseline to 13.95 (SD = 8.49, n = 41), 13.29 (SD = 7.67, n = 38), and 12.39 (SD = 8.49, n = 38) at 1, 3, and 5 years, respectively. Improvement or stability in HRCT images was observed in 72.0% of interstitial lung disease (ILD) patients. Pulmonary arterial hypertension (PAH) remained stable in 5 out of 8 patients at the 5-year follow-up. No adverse events related to UMSCT were observed in any of the patients during the follow-up period. CONCLUSION: UMSCT may provide a safe and feasible treatment option for patients with moderate to severe SSc based on long-term follow-up data. The randomized controlled study will further confirm the clinical efficacy of UMSCT in SSc. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00962923. Key Point • UMSCT is safe and effective for SSc patients.


Subject(s)
Mesenchymal Stem Cells , Scleroderma, Systemic , Humans , Follow-Up Studies , Lung , Retrospective Studies , Scleroderma, Systemic/diagnostic imaging , Scleroderma, Systemic/therapy
6.
Mol Plant ; 17(1): 199-213, 2024 01 01.
Article in English | MEDLINE | ID: mdl-38018035

ABSTRACT

Protein phosphorylation regulates a variety of important cellular and physiological processes in plants. In-depth profiling of plant phosphoproteomes has been more technically challenging than that of animal phosphoproteomes. This is largely due to the need to improve protein extraction efficiency from plant cells, which have a dense cell wall, and to minimize sample loss resulting from the stringent sample clean-up steps required for the removal of a large amount of biomolecules interfering with phosphopeptide purification and mass spectrometry analysis. To this end, we developed a method with a streamlined workflow for highly efficient purification of phosphopeptides from tissues of various green organisms including Arabidopsis, rice, tomato, and Chlamydomonas reinhardtii, enabling in-depth identification with high quantitative reproducibility of about 11 000 phosphosites, the greatest depth achieved so far with single liquid chromatography-mass spectrometry (LC-MS) runs operated in a data-dependent acquisition (DDA) mode. The mainstay features of the method are the minimal sample loss achieved through elimination of sample clean-up before protease digestion and of desalting before phosphopeptide enrichment and hence the dramatic increases of time- and cost-effectiveness. The method, named GreenPhos, combined with single-shot LC-MS, enabled in-depth quantitative identification of Arabidopsis phosphoproteins, including differentially phosphorylated spliceosomal proteins, at multiple time points during salt stress and a number of kinase substrate motifs. GreenPhos is expected to serve as a universal method for purification of plant phosphopeptides, which, if samples are further fractionated and analyzed by multiple LC-MS runs, could enable measurement of plant phosphoproteomes with an unprecedented depth using a given mass spectrometry technology.


Subject(s)
Arabidopsis , Animals , Arabidopsis/metabolism , Phosphopeptides/analysis , Phosphopeptides/chemistry , Phosphopeptides/metabolism , Tandem Mass Spectrometry/methods , Reproducibility of Results , Phosphorylation , Phosphoproteins/metabolism
7.
Virus Res ; 339: 199269, 2024 01 02.
Article in English | MEDLINE | ID: mdl-37952688

ABSTRACT

Cis-acting replication element (cre) is required for generating a diuridylylated VPg that acts as a protein primer to initiate the synthesis of picornaviral genome or antigenome. The cre is a stem-loop structure, dependent of different picornaviruses, located in different genomic regions. The AAACA motif is highly conserved in the apical loop of cre among several picornaviral members, and plays a key role in synthesizing a diuridylylated VPg. We previously demonstrated that senecavirus A (SVA) also possesses an AAACA-containing cre in its genome. Its natural cre (Nc), if functionally inactivated through site-directed mutagenesis (SDM), would confer a lethal impact on virus recovery, whereas an artificial cre (Ac) is able to compensate for the Nc-caused functional inactivation, leading to successful rescue of a viable SVA. In this study, we constructed a set of SVA cDNA clones. Each of them contained one functionally inactivated Nc, and an extra SDM-modified Ac. Every cDNA clone had a unique SDM-modified Ac. The test of virus recovery showed that only two SVAs were rescued from their individual cDNA clones. They were AAACU- and AAACC-containing Ac genotypes. Both viruses were serially passaged in vitro for analyzing their viral characteristics. The results showed that both AAACU and AAACC genotypes were genetically stable during twenty passages, implying when the Nc was functionally inactivated, SVA could still use an AAACH-containing Ac to complete its own replication cycle.


Subject(s)
Picornaviridae , RNA, Viral , Humans , Base Sequence , RNA, Viral/genetics , DNA, Complementary , HeLa Cells , Nucleic Acid Conformation , Picornaviridae/genetics , Virus Replication/genetics
8.
Microb Pathog ; 186: 106503, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38142905

ABSTRACT

Porcine epidemic diarrhea (PED), caused by porcine epidemic diarrhea virus (PEDV), is an acute and highly contagious enteric disease with a high mortality rate in suckling piglets. Identification of proteins associated with PEDV infection may provide insights into the pathogenesis of this viral disease. In this study, we employed tandem mass tag (TMT) quantitative protein analysis to investigate proteomic changes in PK15 cells following PEDV infection, and differential protein expression profiles were obtained at 0 h, 24 h, and 48 h post-infection. Overall, a total of 6330 proteins were identified. Applying criteria for fold change >1.5 < 0.67 and p-values <0.05 resulted in the identification of 59 up-regulated proteins and 103 down-regulated proteins that exhibited significant alterations in the H24 group compared to the H0 group. The H48 group demonstrated significant upregulation of 110 proteins and downregulation of 144 proteins compared to the H0 group; additionally, there were also 10 upregulated and 30 downregulated proteins in the H48 group when compared to the H24 group. These differentially expressed proteins (DEPs) were involved in immune response regulation, signal transduction, lipid transport and metabolism processes as well as cell apoptosis pathways. Based on these DEPs, we propose that PEDV may disrupt signal transduction pathways along with lipid transport and metabolism processes leading to maximal viral replication, it may also trigger inflammatory cascades accordingly. These findings could provide valuable information for elucidating specific pathogenesis related to PEDV infection while contributing towards developing new antiviral strategies.


Subject(s)
Porcine epidemic diarrhea virus , Swine Diseases , Animals , Swine , Porcine epidemic diarrhea virus/physiology , Proteomics/methods , Proteins/metabolism , Signal Transduction , Lipids
9.
Viruses ; 15(10)2023 10 12.
Article in English | MEDLINE | ID: mdl-37896857

ABSTRACT

Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that induces diarrhea and death in neonatal piglets, resulting in substantial economic losses to the global swine industry. The mechanisms of PEDV infection and the roles of host factors are still under exploration. In this study, we used the ferroptosis pathway downstream target activator (1S,3R)-RSL3 compound as a starting point, combined with the interactions of N-acetylcysteine and deferoxamine, to elucidate the effects of a series of compounds on PEDV proliferation. We also established glutathione peroxidase 4 (GPX4) gene overexpression to further elucidate the relationship between the ferroptosis pathway and PEDV. (1S,3R)-RSL3 inhibited PEDV replication in Vero cells, while N-acetylcysteine and deferoxamine promoted its proliferation. In addition, (1S,3R)-RSL3 mainly affected the replication stage of PEDV. Overexpression of GPX4 promoted PEDV proliferation, indicating that the ferroptosis pathway could influence PEDV replication in Vero cells. This study focused on the mechanism of (1S,3R)-RSL3 inhibition on PEDV, laying the foundation for exploring the pathogenic mechanisms of PEDV and drug development.


Subject(s)
Coronavirus Infections , Ferroptosis , Porcine epidemic diarrhea virus , Swine Diseases , Chlorocebus aethiops , Animals , Swine , Vero Cells , Porcine epidemic diarrhea virus/genetics , Acetylcysteine , Deferoxamine , Diarrhea , Virus Replication
10.
Arch Virol ; 168(10): 256, 2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37737963

ABSTRACT

Senecavirus A (SVA) can cause a vesicular disease in swine. It is a positive-strand RNA virus belonging to the genus Senecavirus in the family Picornaviridae. Positive-strand RNA viruses possess positive-sense, single-stranded genomes whose untranslated regions (UTRs) have been reported to contain cis-acting RNA elements. In the present study, a total of 100 SVA isolates were comparatively analyzed at the genome level. A highly conserved fragment (HCF) was found to be located in the 3D sequence and to be close to the 3' UTR. The HCF was computationally predicted to form a stem-loop structure. Eight synonymous mutations can individually disrupt the formation of a single base pair within the stem region. We found that SVA itself was able to tolerate each of these mutations alone, as evidenced by the ability to rescue all eight single-site mutants from their individual cDNA clones, and all of them were genetically stable during serial passaging. However, the replication-competent SVA could not be rescued from another cDNA clone containing all eight mutations. The failure to recover SVA might be attributed to disruption of the predicted stem-loop structure, whereas introduction of a wild-type HCF into the cDNA clone with eight mutations still had no effect on virus recovery. These results suggest that the putative stem-loop structure at the 3' end of the 3D sequence is a cis-acting RNA element that is required for SVA growth.


Subject(s)
Picornaviridae , Animals , Swine , DNA, Complementary , Picornaviridae/genetics , Positive-Strand RNA Viruses , 3' Untranslated Regions/genetics , Conserved Sequence
11.
Front Microbiol ; 14: 1164170, 2023.
Article in English | MEDLINE | ID: mdl-37213521

ABSTRACT

Introduction: Pseudorabies virus (PRV) is a herpesvirus that can infect domestic animals, such as pigs, cattle and sheep, and cause fever, itching (except pigs), and encephalomyelitis. In particular, the emergence of PRV variants in 2011 have resulted in serious economic losses to the Chinese pig industry. However, the signaling pathways mediated by PRV variants and their related mechanisms are not fully understood. Methods: Here, we performed RNA-seq to compare the gene expression profiling between PRV virulent SD2017-infected PK15 cells and Bartha-K/61-infected PK15 cells. Results: The results showed that 5,030 genes had significantly different expression levels, with 2,239 upregulated and 2,791 downregulated. GO enrichment analysis showed that SD2017 significantly up-regulated differentially expressed genes (DEGs) were mainly enriched in the binding of cell cycle, protein and chromatin, while down-regulated DEGs were mainly enriched in ribosomes. KEGG enrichment analysis revealed that the pathways most enriched for upregulated DEGs were pathways in cancer, cell cycle, microRNAs in cancer, mTOR signaling pathway and autophagy-animal. The most down-regulated pathways of DEGs enrichment were ribosome, oxidative phosphorylation, and thermogenesis. These KEGG pathways were involved in cell cycle, signal transduction, autophagy, and virus-host cell interactions. Discussion: Our study provides a general overview of host cell responses to PRV virulent infection and lays a foundation for further study of the infection mechanism of PRV variant strain.

12.
Mol Cell Proteomics ; 22(7): 100582, 2023 07.
Article in English | MEDLINE | ID: mdl-37225018

ABSTRACT

Carbon metabolism is central to photosynthetic organisms and involves the coordinated operation and regulation of numerous proteins. In cyanobacteria, proteins involved in carbon metabolism are regulated by multiple regulators including the RNA polymerase sigma factor SigE, the histidine kinases Hik8, Hik31 and its plasmid-borne paralog Slr6041, and the response regulator Rre37. To understand the specificity and the cross-talk of such regulations, we simultaneously and quantitatively compared the proteomes of the gene knockout mutants for the regulators. A number of proteins showing differential expression in one or more mutants were identified, including four proteins that are unanimously upregulated or downregulated in all five mutants. These represent the important nodes of the intricate and elegant regulatory network for carbon metabolism. Moreover, serine phosphorylation of PII, a key signaling protein sensing and regulating in vivo carbon/nitrogen (C/N) homeostasis through reversible phosphorylation, is massively increased with a concomitant significant decrease in glycogen content only in the hik8-knockout mutant, which also displays impaired dark viability. An unphosphorylatable PII S49A substitution restored the glycogen content and rescued the dark viability of the mutant. Together, our study not only establishes the quantitative relationship between the targets and the corresponding regulators and elucidated their specificity and cross-talk but also unveils that Hik8 regulates glycogen accumulation through negative regulation of PII phosphorylation, providing the first line of evidence that links the two-component system with PII-mediated signal transduction and implicates them in the regulation of carbon metabolism.


Subject(s)
Carbon , Synechocystis , Phosphorylation , Carbon/metabolism , Proteomics , Synechocystis/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Glycogen/metabolism , Nitrogen , Gene Expression Regulation, Bacterial
13.
Environ Pollut ; 331(Pt 2): 121869, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37225077

ABSTRACT

The widespread presence of carbapenem-resistant Enterobacteriaceae (CRE) and mcr-positive Escherichia coli (MCREC) poses a huge threat to both animal and human health. River water environments are vital reservoirs of antibiotic resistance genes, however, the prevalence and characteristics of CRE and MCREC from large-scale rivers in China have not been reported. In the current study, we sampled 86 rivers from four cities in Shandong Province, China in 2021 and analyzed the prevalence of CRE and MCREC. The blaNDM/blaKPC-2/mcr-positive isolates were characterized with methods including PCR, antimicrobial susceptibility testing, conjugation, replicon typing, whole-genome sequencing and phylogenetic analysis. We found that the prevalence of CRE and MCREC in 86 rivers was 16.3% (14/86) and 27.9% (24/86), respectively and eight rivers carried both mcr-1 and blaNDM/blaKPC-2. A total of 48 Enterobacteriaceae isolates (10 ST11 Klebsiella pneumoniae with blaKPC-2, 12 blaNDM-positive E. coli and 26 MCREC carrying only mcr-1) were obtained in this study and 47 displayed multidrug resistance (MDR). Notably, 10 of the 12 blaNDM-positive E. coli isolates also harbored the mcr-1 gene. The blaKPC-2 gene was located within mobile element ISKpn27-blaKPC-2-ISKpn6 on novel F33:A-:B- non-conjugative MDR plasmids in ST11 K. pneumoniae. The dissemination of blaNDM was mediated by transferable MDR IncB/O plasmids or IncX3 plasmids while mcr-1 was primarily disseminated by highly similar IncI2 plasmids. Notably, these waterborne IncB/O, IncX3 and IncI2 plasmids were all highly similar to previously identified plasmids from animal and human isolates. A phylogenomic analysis revealed that the CRE and MCREC isolates from water environments might be derived from animals and trigger infections in humans. The high prevalence of CRE and MCREC in large-scale environmental rivers is alarming and needs sustained surveillance due to the potential risk for transmission to humans via the food chain (irrigation) or direct contact.


Subject(s)
Carbapenem-Resistant Enterobacteriaceae , Enterobacteriaceae , Animals , Humans , Enterobacteriaceae/genetics , Colistin/pharmacology , Carbapenem-Resistant Enterobacteriaceae/genetics , Escherichia coli/genetics , Rivers , Prevalence , Phylogeny , beta-Lactamases/genetics , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Plasmids , Klebsiella pneumoniae/genetics , Genomics , Water , China/epidemiology
14.
Front Microbiol ; 14: 1133241, 2023.
Article in English | MEDLINE | ID: mdl-37082181

ABSTRACT

Introduction: Salmonella is a ubiquitous foodborne pathogen and mainly transmitted to human farm-to-fork chain through contaminated foods of animal origin. Methods: In this study, we investigated the serotypes, antimicrobial resistance and virulence of Salmonella from China. Results: A total of 617 Salmonella isolates were collected from 4 major food animal species across 23 provi nces in China from 2015-2021. Highest Salmonella prevalence were observed in Guangdong (44.4%) and Sandong (23.7%). Chickens (43.0%) was shown to be the major source of Salmonella contamination, followed by pigs (34.5%) and ducks (18.5%). The number of Salmonella increased significantly from 5.51% to 27.23% during 2015-2020. S. Derby (17.3%), S. Enteritidis (13.1%) and S. Typhimurium (11.4%) were the most common serotypes among 41 serotypes identifiedin this study. Antibiotic susceptibility testing showing that the majority of the Salmonella isolates were resistant to neomycin (99.7%), tetracycline (98.1%), ampicillin (97.4%), sulfadiazine/trimethoprim (97.1%), nalidixic acid (89.1%), doxycycline (83.1%), ceftria xone (70.3%), spectinomycin (67.7%), florfenicol (60.0%), cefotaxime (52.0%) and lomefloxacin (59.8%). The rates of resistance to multiple antibiotics in S. Derby and S.Typhimurium were higher than that in S. Enteritidis. However, the rate of resistance to fosfomycin were observed from higher to lower by S. Derby, S. Enteritidis, and S. Typhimurium. Biofilm formation ability analysis found that 88.49%of the Salmonella were able to produce biofilms, of which 236 Salmonella isolates were strong biofilm producer. Among the 26 types of antibiotics resistance genes (ARGs) were identified in this study, 4 ARGs (tetB,sul2,aadA2, and aph(3')-IIa) were highly prevalent. In addition, 5 ß-lactam resistance genes (bla TEM, bla SHV, bla CMY-2, bla CTX-M, and bla OXA) and 7 quinolone resistance genes (oqxA, oqxB, qnrB, qnrC, qnrD, qnrS, and qeqA) were detected among these isolates. 12 out of 17 virulence genes selected in this study were commonly presented in the chromosomes of tested isolate, with a detection rate of over 80%, including misL, spiA, stn, pagC, iroN, fim, msgA, sopB, prgH, sitC, ttrC, spaN. Discussion: This study provided a systematical updating on surveillance on prevalence of Salmonella from food animals in China, shedding the light on continued vigilance for Salmonella in food animals.

15.
Article in English | MEDLINE | ID: mdl-36901319

ABSTRACT

Spartina alterniflora is considered an invasive species that has affected the biogeochemical circle of carbon in coastal wetlands around the world. Nevertheless, it is still unclear how S. alternation invasion affects the carbon storage capacity of coastal wetlands as carbon pools through bacterial changes. Herein, bacterial communities and soil carbon content in coastal wetland native areas and S. alterniflora invasion areas were detected. It was found that an S. alterniflora invasion brought more organic carbon and resulted in the increase in Proteobacteria in bare flats and Sueada salsa areas. When decomposition capacity was not sufficient, large amounts of organic carbon may be stored in specific chemical forms, such as monosaccharides, carboxylic acids, alcohols, etc. The results have also shown that soil bacterial communities were highly similar between the bare flat and S. alterniflora invasion area, which is extremely conducive to the rapid growth of S. alterniflora. However, an S. alterniflora invasion would decrease total carbon contents and inorganic carbon contents in the Sueada salsa area. This is not conducive to the stability of the soil carbon pool and soil health. These findings may complement, to some extent, the shortcomings of the interaction between S. alterniflora and bacterial communities, and their joint effect on soil carbon storage.


Subject(s)
Soil , Wetlands , Soil/chemistry , Carbon/analysis , Poaceae , Introduced Species , Bacteria , China
16.
J Proteome Res ; 22(4): 1255-1269, 2023 04 07.
Article in English | MEDLINE | ID: mdl-36930737

ABSTRACT

Spatial proteome reorganization in response to a changing environment represents a different layer of adaptation mechanism in addition to differential expression of a subset of stress responsive genes in photosynthetic organisms. Profiling such reorganization events is critically important to extend our understanding how photosynthetic organisms adapt to adverse environments. Thus, we treated a unicellular photosynthetic model cyanobacterium, Synechocystis sp. PCC 6803 (hereafter referred to as Synechocystis), with five different types of abiotic stresses including nitrogen starvation, iron deficiency, cold, heat, and darkness, and systematically identified proteins showing stress-induced differential expression and/or redistribution between the membrane and the soluble fractions using a quantitative proteomics approach. A number of proteins showing such a redistribution in response to a single or multiple types of abiotic stresses were identified. These include 12 ribosomal proteins displaying unanimous cold-induced redistribution to the membrane and the protein FurA, a master regulator of iron acquisition, displaying iron deficiency- and nitrogen starvation-induced redistribution to the membrane. Such findings shed light on a novel regulatory mechanism underlying the corresponding stress responses, and establish the results in the present study as an important resource for future studies intended to understand how photosynthetic organisms cope with adverse environments.


Subject(s)
Iron Deficiencies , Synechocystis , Humans , Proteome/genetics , Proteome/metabolism , Stress, Physiological , Synechocystis/genetics , Synechocystis/metabolism , Nitrogen/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism
17.
Proc Natl Acad Sci U S A ; 120(3): e2217148120, 2023 01 17.
Article in English | MEDLINE | ID: mdl-36630453

ABSTRACT

Modulation of water activation is crucial to water-involved chemical reactions in heterogeneous catalysis. Organic sulfur (COS and CS2) hydrolysis is such a typical reaction involving water (H2O) molecule as a reactant. However, limited by the strong O-H bond in H2O, satisfactory CS2 hydrolysis performance is attained at high temperature above 310 °C, which is at the sacrifice of the Claus conversion, strongly hindering sulfur recovery efficiency improvement and pollution emissions control of the Claus process. Herein, we report a facile oxygen vacancy (VO) engineering on titanium-based perovskite to motivate H2O activation for enhanced COS and CS2 hydrolysis at lower temperature. Increased amount of VO contributed to improved degree of H2O dissociation to generate more active -OH, due to lower energy barrier for H2O dissociation over surface rich in VO, particularly VO clusters. Besides, low-coordinated Ti ions adjacent to VO were active sites for H2O activation. Consequently, complete conversion of COS and CS2 was achieved over SrTiO3 after H2 reduction treatment at 225 °C, a favorable temperature for the Claus conversion, at which both satisfying COS and CS2 hydrolysis performance and improved sulfur recovery efficiency can be obtained simultaneously. Additionally, the origin of enhanced hydrolysis activity from boosted H2O activation by VO was revealed via in-depth mechanism study. This provides more explicit direction for further design of efficacious catalysts for H2O-involved reactions.


Subject(s)
Oxygen , Titanium , Temperature , Hydrolysis , Water/chemistry , Sulfur
18.
Adv Sci (Weinh) ; 10(3): e2205054, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36437038

ABSTRACT

Chlorinated volatile organic compounds (CVOCs) are a class of hazardous pollutants that severely threaten environmental safety and human health. Although the catalytic oxidation technique for CVOCs elimination is effective, enhancing the catalytic efficiency and simultaneously inhibiting the production of organic byproducts is still of great challenge. Herein, Ru-substituted LaMn(Ru)O3+ δ perovskite with Ru-O-Mn structure and weakened Mn-O bond strength has been developed for catalytic oxidation of chlorobenzene (CB). The formed Ru-O-Mn structure serves as favorable sites for CB adsorption and activation, while the weakening of Mn-O bond strength facilitates the formation of active oxygen species and improves oxygen mobility and catalyst reducibility. Therefore, LaMn(Ru)O3+ δ exhibits superior low-temperature activity with the temperature of 90% CB conversion decreasing by over 90 °C compared with pristine perovskite, and the deep oxidation of chlorinated byproducts produced in low temperature is also accelerated. Furthermore, the introduction of water vapor into reaction system triggers the process of hydrolysis oxidation that promotes CB destruction and inhibits the generation of chlorinated byproducts, due to the higher-activity *OOH species generated from the dissociated H2 O reacting with adsorbed oxygen. This work can provide a unique, high-efficiency, and facile strategy for CVOCs degradation and environmental improvement.

19.
Sci Total Environ ; 857(Pt 1): 159306, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36216064

ABSTRACT

As a new type of environmental pollutants, micro/nano plastics (MPs/NPs) derived from plastic products are commonly contact in daily life and lead to some serious health issues. The toxicity effects of MPs/NPs on the human body have aroused wide concerns. Although MPs/NPs have been reported to be transmitted into the kidney and reproductive organs, the molecular mechanisms of MPs/NPs toxicity remain unclear due to the lack of a physiologically relevant organ-organ linking platform in vitro. Here, we present a kidney-testis microfluidic platform (KTP) with NPs exposure that enables the communication of kidney and testis chambers and reproduces endothelium-linked chambers to simulate the state in vivo. The function of KTP was assessed by cell counting kit (CCK-8), tight junction protein claudin-2 and glucose consumption. Results revealed that MPs/NPs entered the kidney and testis via endocytosis. Immunofluorescence and ELISA analysis were performed on KTP at 200 µg/mL PS-NP to identify the dysregulated proteins on cancer-related signaling pathways, including the MAPK signaling pathway (RTK, RAS, ERK, JNK, P38, NRF2, TNF-α, and TNF-α-R) and the PI3K-AKT signaling pathway (PI3K, AKT, MDM2, P53, and ΒΑD). This multi-organ platform (KTP) contributes to clarifying cancer pathways triggered by MPs/NPs exposure and provides a promising method for assessing diseases induced by environmental pollutants.


Subject(s)
Environmental Pollutants , Neoplasms , Water Pollutants, Chemical , Male , Humans , Polystyrenes/toxicity , Microplastics , Testis , Water Pollutants, Chemical/analysis , Microfluidics , Tumor Necrosis Factor-alpha , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt/pharmacology , Kidney , Environmental Pollutants/toxicity , Environmental Pollutants/analysis , Signal Transduction
20.
MicroPubl Biol ; 20222022.
Article in English | MEDLINE | ID: mdl-36439395

ABSTRACT

Spacer acquisition, the first step in CRISPR-Cas adaptive immunity, plays a critical role in establishing and strengthening host defense against mobile genetic elements (MGEs). Here we present a host-virus system, where an increase in the multiplicity of infection (MOI), of a CRISPR-Cas susceptible virus, forces rapid spacer acquisition in the Sulfolobus islandicus LAL14/1 CRISPR arrays. Spacer acquisition was observed as early as 30 minutes post infection, with the newly acquired spacers uniformly distributed across the genome of the virus. Although the newly acquired spacers were predominantly effective only against the CRISPR-Cas susceptible mutant virus, we were able to isolate a host mutant with a novel spacer which provides immunity against the multiple Acr encoding wildtype virus, Sulfolobus islandicus rod-shaped virus 2 (SIRV2).

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