RESUMO
The Klebsiella pneumoniae (K. pneumoniae, Kp) populations carrying both resistance-encoding and virulence-encoding mobile genetic elements (MGEs) significantly threaten global health. In this study, we identified a new anti-CRISPR gene (acrIE10) on a conjugative plasmid with self-target sequence in K. pneumoniae with type I-E* CRISPR-Cas system. AcrIE10 interacts with the Cas7* subunit of K. pneumoniae I-E* CRISPR-Cas system. The crystal structure of the AcrIE10-KpCas7* complex suggests that AcrIE10 suppresses the I-E* CRISPR-Cas by binding directly to Cas7 to prevent its hexamerization, thereby preventing the surveillance complex assembly and crRNA loading. Bioinformatic and functional analyses revealed that AcrIE10 is functionally widespread across diverse species. Our study reports a novel anti-CRISPR and highlights its potential role in spreading resistance and virulence among pathogens.
Assuntos
Proteínas de Bactérias , Sistemas CRISPR-Cas , Klebsiella pneumoniae , Plasmídeos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Plasmídeos/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Virulência/genética , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/genéticaRESUMO
KEY MESSAGE: Two peanut LEC1-type genes exhibit partial functional redundancy. AhNFYB10 could complement almost all the defective phenotypes of lec1-2 in terms of embryonic morphology, while AhNF-YB1 could partially affect these phenotypes. LEAFY COTYLEDON1 (LEC1) is a member of the nuclear factor Y (NF-Y) family of transcription factors and has been identified as a key regulator of embryonic development. In the present study, two LEC1-type genes from Arachis hypogeae were identified and designated as AhNF-YB1 and AhNF-YB10; these genes belong to subgenome A and subgenome B, respectively. The functions of AhNF-YB1 and AhNF-YB10 were investigated by complementation analysis of their defective phenotypes of the Arabidopsis lec1-2 mutant and by ectopic expression in wild-type Arabidopsis. The results indicated that both AhNF-YB1 and AhNF-YB10 participate in regulating embryogenesis, embryo development, and reserve deposition in cotyledons and that they have partial functional redundancy. In contrast, AhNF-YB10 complemented almost all the defective phenotypes of lec1-2 in terms of embryonic morphology and hypocotyl length, while AhNF-YB1 had only a partial effect. In addition, 30-40% of the seeds of the AhNF-YB1 transformants exhibited a decreasing germination ratio and longevity. Therefore, appropriate spatiotemporal expression of these genes is necessary for embryo morphogenesis at the early development stage and is responsible for seed maturation at the mid-late development stage. On the other hand, overexpression of AhNF-YB1 or AhNF-YB10 at the middle to late stages of Arabidopsis seed development improved the weight, oil content, and fatty acid composition of the transgenic seeds. Moreover, the expression levels of several genes associated with fatty acid synthesis and embryogenesis were significantly greater in developing AhNF-YB10-overexpressing seeds than in control seeds. This study provides a theoretical basis for breeding oilseed crops with high yields and high oil content.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arachis/genética , Arachis/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Melhoramento Vegetal , Ácidos Graxos/metabolismo , Desenvolvimento Embrionário , Lipídeos , Sementes/metabolismoRESUMO
As one of the important devices for large-scale electrochemical energy storage, sodium-ion batteries have received much attention due to the abundant resources of raw materials. However, whether it is a base station power source, an energy storage power station, or a start-stop power supply, long energy cycle life (more than 5000 cycles), high stability, and safety performance are application prerequisites. Regrettably, currently, few sodium-ion batteries can meet this requirement, mainly due to shortcomings in positive electrode performance. We report a sufficiently stable sodium-ion battery cathode material, Na2Fe0.95P2O7, that retains 97.5% capacity after 5000 charge/discharge cycles. The use of nonstoichiometry in the lattice enables simultaneous modification of the crystal and electronic structure, promoting Na2Fe0.95P2O7 to be extremely stable while still being able to achieve a capacity of 92 mAh g-1 and stable cycling at high temperatures up to 60 °C. Our results confirm the positive effect of nonstoichiometric ratios on the performance of Na2Fe0.95P2O7 and provide a reliable idea to promote the practical application of sodium-ion batteries.
RESUMO
The Pacific oyster Crassostrea gigas is rich in taurine, which is crucial for its adaptation to the fluctuating intertidal environment and presents significant potential in improving taurine nutrition and boosting immunity in humans. Cysteine dioxygenase (CDO) is a key enzyme involved in the initial step of taurine biosynthesis and plays a crucial role in regulating taurine content in the body. In the present study, polymorphisms of CDO gene in C. gigas (CgCDO) and their association with taurine content were evaluated in 198 individuals. A total of 24 single nucleotide polymorphism (SNP) loci were identified in the exonic region of CgCDO gene by direct sequencing. Among these SNPs, c.279G>A and c.287C>A were found to be significantly associated with taurine content, with the GG and AA genotype at the two loci exhibiting enhanced taurine accumulation (p < 0.05). Haplotype analysis revealed that the 279GG/287AA haplotype had the highest taurine content of 29.24 mg/g, while the 279AA/287CC haplotype showed the lowest taurine content of 21.19 mg/g. These results indicated that the SNPs of CgCDO gene could influence the taurine content in C. gigas and have potential applications in the selective breeding of high-taurine varieties.
Assuntos
Crassostrea , Cisteína Dioxigenase , Polimorfismo de Nucleotídeo Único , Taurina , Taurina/metabolismo , Crassostrea/genética , Crassostrea/metabolismo , Crassostrea/enzimologia , Animais , Cisteína Dioxigenase/genética , Cisteína Dioxigenase/metabolismo , HaplótiposRESUMO
The Pacific oyster Crassostrea gigas is renowned for its high zinc content, but the significant variation among individuals diminishes its value as a reliable source of zinc supplementation. The Zrt/Irt-like protein 1 (ZIP1), a pivotal zinc transporter that facilitates zinc uptake in various organisms, plays crucial roles in regulating zinc content. In the present study, polymorphisms of a ZIP1 gene in C. gigas (CgZIP1-II) were investigated, and their association with zinc content was evaluated through preliminary association analysis in 41 oysters and verification analysis in another 200 oysters. A total of 17 single nucleotide polymorphisms (SNPs) were identified in the exonic region of CgZIP1-II gene, with c.503A>G significantly associated with zinc content. Protein sequence and structure prediction showed that c.503A>G caused a p.Met110Val nonsynonymous mutation located in the metal-binding region of CgZIP1-II, which could influence its affinity for zinc ions, thereby modulating its zinc transport functionality. These results indicate the potential influence of CgZIP1-II polymorphisms on zinc content and provide candidate markers for selecting C. gigas with high zinc content.
Assuntos
Proteínas de Transporte de Cátions , Crassostrea , Polimorfismo de Nucleotídeo Único , Zinco , Animais , Zinco/metabolismo , Crassostrea/genética , Crassostrea/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/químicaRESUMO
Lead (Pb), a heavy metal environmental pollutant, poses a threat to the health of humans and birds. Inflammation is one of the most common pathological phenomena in the case of illness and poisoning. However, the underlying mechanisms of inflammation remain unclear. The cerebellum and the thalamus are important parts of the nervous system. To date, there have been no reports of Pb inducing inflammation in animal cerebellums or thalami. Selenium (Se) can relieve Pb poisoning. Therefore, we aimed to explore the mechanism by which Se alleviates Pb toxicity to the cerebellums and thalami of chickens by establishing a chicken Pb or/and Se treatment model. Our results demonstrated that exposure to Pb caused inflammatory damage in cerebellums and thalami, evidenced by the characteristics of inflammation, the decrease in anti-inflammatory factors (interleukin (IL)-2 and interferon-γ (INF-γ)), and the increase in pro-inflammatory factors (IL-4, IL-6, IL-12ß, IL-17, and nitric oxide (NO)). Moreover, we found that the IL-2/IL-17-NO pathway took part in Pb-caused inflammatory injury. The above findings were reversed by the supplementation of dietary Se, meaning that Se relieved inflammatory damage caused by Pb via the IL-2/IL-17-NO pathway. In addition, an up-regulated oxidative index malondialdehyde (MDA) and two down-regulated antioxidant indices (glutathione (GSH) and total antioxidant capacity (TAC)) were recorded after the chickens received Pb stimulation, indicating that excess Pb caused an oxidant/antioxidant imbalance and oxidative stress, and the oxidative stress mediated inflammatory damage via the GSH-IL-2 axis. Interestingly, exposure to Pb inhibited four glutathione peroxidase (GPx) family members (GPx1, GPx2, GPx3, and GPx4), three deiodinase (Dio) family members (Dio1, Dio2, and Dio3), and fifteen other selenoproteins (selenophosphate synthetase 2 (SPS2), selenoprotein (Sel)H, SelI, SelK, SelM, SelO, SelP1, SelPb, SelS, SelT, SelU, and selenoprotein (Sep)n1, Sepw1, Sepx1, and Sep15), suggesting that Pb reduced antioxidant capacity and resulted in oxidative stress involving the SPS2-GPx1-GSH pathway. Se supplementation, as expected, reversed the changes mentioned above, indicating that Se supplementation improved antioxidant capacity and mitigated oxidative stress in chickens. For the first time, we discovered that the SPS2-GPx1-GSH-IL-2/IL-17-NO pathway is involved in the complex inflammatory damage mechanism caused by Pb in chickens. In conclusion, this study demonstrated that Se relieved Pb-induced oxidative stress and inflammatory damage via the SPS2-GPx1-GSH-IL-2/IL-17-NO pathway in the chicken nervous system. This study offers novel insights into environmental pollutant-caused animal poisoning and provides a novel theoretical basis for the detoxification effect of Se against oxidative stress and inflammation caused by toxic pollutants.
RESUMO
Four undescribed naturally diterpenolignans, and two cephalotane diterpenoids, along with seven known compounds, including two pairs of enantiomers, were isolated from the twigs and leaves of Cephalotaxus oliveri Mast. Their structures were elucidated via spectroscopic data interpretation, chiral-phase HPLC analysis, NMR calculations, and electronic circular dichroism analysis. All the isolated compounds were evaluated for their cytotoxic activities against three kinds of human tumor cell lines. Among them, compound 8 exhibited the most potent activities against MCF-7, HepG2 and A549 cell lines with IC50 values of 2.83, 4.75 and 2.77 µM, respectively.
Assuntos
Antineoplásicos Fitogênicos , Cephalotaxus , Diterpenos , Humanos , Cephalotaxus/química , Estrutura Molecular , Diterpenos/química , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Folhas de Planta/química , Dicroísmo CircularRESUMO
Four new lignans named cephaliverins A-D (1-4), along with seven known analogues (5-11), were isolated from Cephalotaxus oliveri Mast. Their structures were elucidated on the basis of HR-ESI-MS and NMR analyses, and their absolute configurations were determined by ECD comparison. Cephaliverin A (1), herpetotriol (5) and hedyotol A (6) exhibited moderate antitumor activity against HepG2 and A549 cell lines.
Assuntos
Antineoplásicos Fitogênicos , Cephalotaxus , Lignanas , Lignanas/isolamento & purificação , Lignanas/farmacologia , Lignanas/química , Humanos , Cephalotaxus/química , Estrutura Molecular , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Células Hep G2 , Células A549 , ChinaRESUMO
Layered transition metal oxides are widely considered as ideal cathode materials for SIBs. However, the existing P2 and O3 structures possess specific issues, which limit their practical applications. To address these issues, this work designed a novel intergrowth layered oxide cathode with P2 and O3 phases by implementing Cu and Ti into the structure with the formation of high-entropy cathode materials with superior performance for SIBs. The electrochemical test results show that the optimized high-entropy cathode with the P2/O3 intergrowth structure possesses a high initial discharge capacity of 157.85â mAh g-1 at 0.1â C, an excellent rate performance of 84.41â mAh g-1 at 10â C, and long-term stability with capacity retention of 83.25 % after 500 cycles at 5â C. Furthermore, the analysis results of ex situ XRD and inâ situ XRD indicate that the adverse phase transition of P2-O2 under high voltage is effectively suppressed. This work indicates that the integration of high-entropy strategy with the two-phase intergrowth structure can effectively stabilize the layered structure, suppress the slipping of transition metal layers, and improve electrochemical performance, which provides a new approach for designing high-performance and practical layered transition metal oxide cathode materials for advanced SIBs.
RESUMO
BACKGROUND: Despite the efficacy of absolute ethanol (EtOH), its radiolucency introduces several risks in interventional therapy for treating vascular malformations. This study aims to develop a novel radiopaque ethanol injection (REI) to address this issue. METHODS: Iopromide is mixed with ethanol to achieve radiopacity and improve the physicochemical properties of the solution. Overall, 82 male New Zealand white rabbits are selected for in vivo radiopacity testing, peripheral vein sclerosis [animals were divided into the following 5 groups (n = 6): negative control (NC, saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), low-dose REI (L-D REI, 0.125 ml/kg), moderate-dose REI (M-D REI, 0.250 ml/kg), and high-dose REI (H-D REI 0.375 ml/kg)], pharmacokinetic analyses (the blood sample was harvested before injection, 5 min, 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, and 8 h after injection in peripheral vein sclerosis experiment), peripheral artery embolization [animals were divided into the following 5 groups (n = 3): NC (saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)], kidney transcatheter arterial embolization [animals were divided into the following 4 groups (n = 3): positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg); each healthy kidney was injected with saline as negative control], and biosafety evaluations [animals were divided into the following 5 groups (n = 3): NC (0.250 ml/kg), high-dose EtOH (0.375 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)]. Then, a prospective cohort study involving 6 patients with peripheral venous malformations (VMs) is performed to explore the clinical safety and effectiveness of REI. From Jun 1, 2023 to August 31, 2023, 6 patients [age: (33.3 ± 17.2) years] with lingual VMs received sclerotherapy of REI and 2-month follow-up. Adverse events and serious adverse events were evaluated, whereas the efficacy of REI was determined by both the traceability of the REI under DSA throughout the entire injection and the therapeutic effect 2 months after a single injection. RESULTS: The REI contains 81.4% ethanol (v/v) and 111.3 mg/ml iodine, which can be traced throughout the injection in the animals and patients. The REI also exerts a similar effect as EtOH on peripheral venous sclerosis, peripheral arterial embolization, and renal embolization. Furthermore, the REI can be metabolized at a similar rate compared to EtOH and Ultravist® and did not cause injury to the animals' heart, liver, spleen, lungs, kidneys and brain. No REI-related adverse effects have occurred during sclerotherapy of VMs, and 4/6 patients (66.7%) have achieved complete response at follow-up. CONCLUSION: In conclusion, REI is safe, exerts therapeutic effects, and compensates for the radiolucency of EtOH in treating VMs. TRIAL REGISTRATION: The clinical trial was registered as No. ChiCTR2300071751 on May 24 2023.