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Pinellia ternata (Thunb.) Briet., a valuable herb native to China, is susceptible to the "sprout tumble" phenomenon because of high temperatures, resulting in a significant yield reduction. However, the molecular regulatory mechanisms underlying the response of P. ternata to heat stress are not well understood. In this study, we integrated transcriptome and miRNAome sequencing to identify heat-response genes, microRNAs (miRNAs), and key miRNA-target pairs in P. ternata that differed between heat-stress and room-temperature conditions. Transcriptome analysis revealed extensive reprogramming of 4,960 genes across various categories, predominantly associated with cellular and metabolic processes, responses to stimuli, biological regulation, cell parts, organelles, membranes, and catalytic and binding activities. miRNAome sequencing identified 1,597 known/conserved miRNAs that were differentially expressed between the two test conditions. According to the analysis, genes and miRNAs associated with the regulation of transcription, DNA template, transcription factor activity, and sequence-specific DNA binding pathways may play a major role in the resistance to heat stress in P. ternata. Integrated analysis of the transcriptome and miRNAome expression data revealed 41 high-confidence miRNA-mRNA pairs, forming 25 modules. MYB-like proteins and calcium-responsive transcription coactivators may play an integral role in heat-stress resistance in P. ternata. Additionally, the candidate genes and miRNAs were subjected to quantitative real-time polymerase chain reaction to validate their expression patterns. These results offer a foundation for future studies exploring the mechanisms and critical genes involved in heat-stress resistance in P. ternata.
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Respuesta al Choque Térmico , MicroARNs , Pinellia , Plantones , Transcriptoma , Pinellia/genética , Pinellia/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Respuesta al Choque Térmico/genética , Plantones/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las PlantasRESUMEN
UBE2C is overexpressed in gliomas, and its overexpression has been reported to be correlated with the drug resistance of gliomas to some extent. In this study, we explore the role of UBE2C in regulating temozolomide (TMZ) resistance in glioma and investigate the underlying mechanisms involved. Twenty normal brain tissues and 100 glioma tissues from 50 TMZ-resistant patients and 50 TMZ-sensitive patients are included in this study. TMZ-resistant cell lines are constructed to explore the role of UBE2C in regulating glioma cell viability and TMZ resistance. Our results show that both the mRNA and protein levels of UBE2C are significantly elevated in the brain tissues of glioma patients, especially in those of TMZ-resistant patients. Consistently, UBE2C expression is markedly upregulated in TMZ-resistant cell lines. Overexpression of UBE2C rescues glioma cells from TMZ-mediated apoptosis and enhances cell viability. In contrast, downregulation of UBE2C expression further enhances TMZ function, increases cell apoptosis and decreases cell viability. Mechanistically, UBE2C overexpression decreases p53 expression and enhances aerobic glycolysis level by increasing ATP level, lactate production, and glucose uptake. Downregulation of p53 level abolishes the role of UBE2C downregulation in inhibiting TMZ resistance and aerobic glycolysis in glioma cells. Moreover, an animal assay confirms that downregulation of UBE2C expression further suppresses tumor growth in the context of TMZ treatment. Collectively, this study reveals that downregulation of UBE2C expression enhances the sensitivity of glioma cells to TMZ by regulating the expression of p53 to inhibit aerobic glycolysis.
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Neoplasias Encefálicas , Resistencia a Antineoplásicos , Glioma , Glucólisis , Temozolomida , Proteína p53 Supresora de Tumor , Enzimas Ubiquitina-Conjugadoras , Temozolomida/farmacología , Humanos , Resistencia a Antineoplásicos/genética , Glioma/metabolismo , Glioma/genética , Glioma/tratamiento farmacológico , Glioma/patología , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Glucólisis/efectos de los fármacos , Glucólisis/genética , Línea Celular Tumoral , Animales , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Antineoplásicos Alquilantes/farmacología , Ratones Desnudos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones , Apoptosis/efectos de los fármacos , Apoptosis/genética , Masculino , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , FemeninoRESUMEN
Two Mo-Ti-mixed oxide clusters, Ti6Mo4 and Ti4Mo4, which contain the {Mo2V} unit commonly observed in many polyoxomolybdates, were successfully synthesized. The introduction of a {Mo2V} dopant into a titanium-oxide cluster (TOC) results in a red shift of the absorption edge, hence leading to a substantial enhancement of visible-light absorption. The band gap electron transition mainly involves the ligand-to-metal charge transfer (LMCT, benzoate-to-Mo) and MoV d-d transition. Both clusters show favorable visible-light responsiveness and charge-separation efficiency. Both serve as heterogeneous photocatalysts and exhibit excellent catalytic activity in CO2/epoxide cycloadditions under very mild conditions. The mechanism study suggests that the catalytically active sites are mainly MoV, and the photogenerated electrons and holes are both involved. Ti6Mo4 exhibits better photocatalytic activity than Ti4Mo4, demonstrating the crucial role of the titanium-oxide core, which corresponds to improved light absorption and charge-separation efficiency. Our findings highlight the potential of the {Mo2V} unit in constructing Mo-Ti-mixed oxide clusters with interesting topologies and excellent solar-light-harvesting activity.
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Five cluster polymers based on heterometal-doped titanium-oxide cluster (TOC) monomers are reported. The monomers feature Ti10-oxide cluster cores and are connected to the divalent closed-shell heterometal anchors by salicylate ligands. The Sr2+, Ba2+, and Pb2+ dopants cause the monomers to bind head-to-head and generate linear chains, while the Ca2+ and Cd2+ lead to head-to-tail connections and zigzag chains. The cluster polymers are responsive to visible-light up to 565 nm and photo-catalytically active in both H2 evolution and CO2/epoxide cycloaddition reactions. The photo-absorption, photo-charge separation, and photocatalytic properties of the cluster polymers are dependent on the heterometal dopants in order Cd > Pb > Ba > Sr > Ca. Heterometals serve as the catalytic sites in the cluster polymers, which depending on the contribution of the pCB bottom, facilitate photo-charge separation and interfacial charge transfer, further enhancing catalytic activity. The tunable compositions and topologies of the cluster polymers shown herein may inspire the design and synthesis of more multidimensional functional metal-oxide cluster materials for a variety of applications in the future.
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The CO2 cycloaddition to epoxides is an efficient method for CO2 capture and storage, important not only for reducing greenhouse gas emission but also for producing cyclic carbonates, which are valuable industrial materials. In this study, we report a novel high-nuclearity titanium oxide cluster (TOC) inlayed with main-group element Pb2+, H2Ti16Pb9O24(SA)18(DMF)10(OH2)2 (denoted as 1; SA = salicylate; DMF = N,N-dimethylformamide), which has the property of visible-light absorption and has shown high catalytic activities for cycloadditions of CO2 under visible-light irradiation. The cluster was synthesized in a high yield in a facial solvothermal process. Its structure and electronic structure were characterized by single-crystal X-ray diffraction, density functional theory calculations, and complementary techniques. The cycloaddition reactions were performed under solvent-free conditions. While the catalytic activity due to the Lewis acidity was moderate, visible-light irradiation further folded the reaction rates. The turnover number reached 3400 with a turnover frequency of 120 h-1. Mechanism studies indicated a synergistic effect of the Lewis acidity and photogenerated charge carriers. The performance of 1 in reversible I2 uptake was also investigated. This study demonstrates the high potential of heterometal-decorated TOCs in the cost-effective and efficient CO2 cycloaddition reaction under mild conditions.
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Anaerobic digestion (AD) of waste activated sludge (WAS) is commonly limited to poor synergistic cooperation of four stages including hydrolysis, acidogenesis, acetogenesis and methanogenesis. Dissimilatory metal reduction that induced by metal-based conductive materials is promising strategy to regulate anaerobic metabolism with the higher metabolic driving force. In this study, MnO2 as inducer of dissimilatory manganese reduction (DMnR) was added into WAS-feeding AD system for mediating complicated anaerobic metabolism. The results demonstrated that main operational performances including volatile solid (VS) degradation efficiency and cumulative CH4 production with MnO2 dosage of 60 mg/g·VS reached up to maximum 53.6 ± 3.4% and 248.2 ± 10.1 mL/g·VS while the lowest operational performances in control group (38.5 ± 2.8% and 183.5 ± 8.5 mL/g·VS) was originated from abnormal operation of four stages. Furthermore, high-throughput 16 S rRNA pyrosequencing revealed that enrichment of dissimilatory manganese-reducing contributors and methanogens such as Thermovirga, Christensenellaceae_R_7_group and Methanosaeta performed the crucial role in short-chain fatty acids (SCFAs) oxidation and final methanogenesis, which greatly optimized operational environment of hydrolysis, acidogenesis and acetogenesis. More importantly, analysis of functional genes expression proved that abundances of genes encoding enzymes participated in acetate oxidation, direct interspecies electron transfer (DIET) and CO2 reduction pathway were simultaneously up-regulated with the optimum MnO2 dosage, suggesting that DMnR with SCFAs oxidation as electron sink could benefit stable operation of four stages via triggering effective DIET-based microbial interaction mode.
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Manganeso , Aguas del Alcantarillado , Anaerobiosis , Hidrólisis , Compuestos de Manganeso , Óxidos , Ácidos Grasos Volátiles , Metano , Reactores BiológicosRESUMEN
INTRODUCTION AND HYPOTHESIS: The objective was to evaluate the efficacy and safety of vaginal electrical stimulation (VES) as an alternative or adjunct treatment for overactive bladder (OAB) syndrome in women. METHODS: Five English-language databases and four Chinese-language databases were searched to identify relevant studies. Studies comparing VES (VES alone or VES plus other interventions) with other interventions (medicines, bladder training, or PFMT) were included. Voiding diary, quality of life (QoL), and adverse events were extracted from the included studies for comparison. RESULTS: Seven trials with 601 patients in total were reviewed. The results showed that when compared with other interventions, VES alone significantly improved urgency episodes (p = 0.0008) and voiding frequency (p = 0.01), but did not significantly reduce nocturia (p = 0.85), urinary incontinence episodes (p = 0.90) and number of pads (p = 0.87). When VES plus other interventions was compared with other interventions, the former significantly improved voiding frequency (p < 0.00001), nocturia (p < 0.00001), and number of pads (p = 0.03), but it did not significantly reduce urinary incontinence episodes (p = 0.24). Both VES alone (p < 0.00001) and VES plus other interventions (p = 0.003) showed significant benefit on QoL. CONCLUSIONS: This study demonstrated that VES alone decreased urgency episodes and QoL better than other therapies. Although VES alone reduced voiding frequency better and VES plus other therapies decreased nocturia, number of pads, urgency episodes, and QoL better than other therapies, the results should be interpreted with caution for clinical practice because some of the RCTs included were of low quality and because of the small number of studies included.
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BACKGROUND: Osteoarthritis (OA) is a common disease with a complex pathology. This study aimed to investigate the correlation between the aberrant upregulation of miR-181b and ferroptosis in chondrocytes during the progression of OA. METHODS: An OA cell model was constructed with erastin. Ferrostatin-1 (Fer), bioinformatics, and dual-luciferase activity reports were used to investigate the effect of miR-181b on OA. Finally, a rat model of OA was induced by monosodium iodoacetate to verify that miR-181b inhibits SLC7A11 gene expression and increases ferroptosis. RESULTS: The results showed that Fer could effectively reverse the erastin-induced inhibition of human chondrocyte viability, increase the level of collagenous proteins in human chondrocytes, and inhibit oxidative stress and ferroptosis. MiR-181b is abnormally elevated in OA cell models. Transfection of a miR-181b inhibitor could increase the expression levels of the ferroptosis-related proteins solute carrier family 7 members 11 (SLC7A11) and glutathione peroxidase 4 (GPX4), thereby inhibiting the occurrence of ferroptosis in chondrocytes. In addition, hsa-miR-181b-5p and SLC7A11 have a targeted regulatory effect. Transfection of SLC7A11 siRNA effectively abrogated the increase in chondrocyte viability induced by the miR-181 inhibitor and increased ferroptosis. Finally, miR-181b was shown to exacerbate OA disease progression by inhibiting SLC7A11 gene expression and increasing ferroptosis in a rat OA model. CONCLUSIONS: Elevating miR-181b may mediate chondrocyte ferroptosis by targeting SLC7A11 in OA.
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Sistema de Transporte de Aminoácidos y+ , Condrocitos , Ferroptosis , MicroARNs , Osteoartritis , Animales , Humanos , Ratas , Sistema de Transporte de Aminoácidos y+/genética , MicroARNs/genética , ARN Interferente PequeñoRESUMEN
Balsam (Impatiens balsamina L.) is an ornamental plant cultivated extensively in China and elsewhere, but it has also been used as a medicinal plant for thousands of years (Qian et al., 2023). In 2022, an examination of 10 garden-grown I. balsamina plants in Chaoyang, Beijing, China revealed eight plants with blotches, mosaic symptoms, and deformed leaves (Fig. S1A). Total RNA was extracted from the symptomatic leaf tissue of these eight plants using the TRIzol reagent (Invitrogen, USA). Four RNA preparations (high quality and quantity) were combined for the small RNA sequencing analysis (TIANGEN Biotech Co., China). A total of 16,509,586 clean reads (18-30 nt) were obtained and assembled into larger contigs using Velvet 1.0.5. A search of the National Center for Biotechnology Information non-redundant database using BLASTX indicated 72, 24, and 19 contigs were homologous to broad bean wilt virus 2 (BBWV2), cucumber mosaic virus (CMV), and impatiens cryptic virus 1 (ICV1) sequences (Zheng et al., 2022), respectively. To verify the next-generation sequencing data, the following three sets of primer pairs were designed according to the contig sequences of these three viruses: CMV-F:5'-ATGGACAAATCTGAATCAACCAGTGC-3'/CMV-R: 5'-CCGTAAGCTGGATGGACAACC-3'; BBWV2-F:5'-CAATTTGGACAACTACAATTTGCC-3'/ BBWV2-R: 5'-GCTGAGTCTAAATCCCATCTATC-3'; and ICV1-F: 5'-CGCACAACT CTACAAT GACATGGTC-3'/ICV1-R: 5'-AGTTCCATCGTCCAGTAGGCG-3'. The primers were used to amplify CMV, BBWV2, and ICV1 sequences by reverse transcription-polymerase chain reaction (RT-PCR), with individual RNA preparations serving as the template. The CMV, BBWV2, and ICV1 target sequences were amplified from eight, four, and four samples, respectively (Fig. S1B). To evaluate virus infectivity, Nicotiana benthamiana seedlings were inoculated using a leaf tissue extract prepared from an infected I. balsamina plant. At 7 days post-inoculation, disease symptoms were detected on N. benthamiana systemic leaves (e.g., deformation and apical necrosis) (Fig. S1C). Confirmation tests involving RT-PCR indicated the N. benthamiana plants were infected with BBWV2 and CMV, but not with ICV1 (Fig. S1D). To obtain the complete BBWV2 genome sequence (RNA1 and RNA2), virus-specific PCR primers (Table S1) were designed to produce the terminal sequences via 5' and 3' rapid amplification of cDNA ends (RACE), which was completed using the SMARTer RACE 5'/3' Kit (Clontech, China). The RNA1 and RNA2 sequences comprised 5,957 nt (GenBank: OQ857921) and 3,614 nt (GenBank: OQ857922), respectively. The BLAST analyses revealed RNA1 and RNA2 were similar to sequences in other BBWV2 isolates (sequence identities of 78.88% to 95.15% and 80.83% to 91.51%, respectively). Using the neighbor-joining method and MEGA 7.0, the phylogenetic relationships between the BBWV2 isolated in this study and other isolates were determined on the basis of the full-length RNA1 and RNA2 sequences (Kumar et al., 2016). According to the RNA1 and RNA2 sequences, the BBWV2 isolated in this study was most closely related to the BBWV2 isolate from Gynura procumbens (GenBank: KX686589) and the BBWV2 isolate from Nicotiana tabacum (GenBank: KX650868), respectively (Fig. S1E). To the best of our knowledge, this is the first report of I. balsamina naturally infected with BBWV2 in China. The study findings may be useful for detecting BBWV2 in I. balsamina and for diagnosing and managing the associated disease. The authors declare no conflict of interest. Yanhong Qiu and Haijun Zhang contributed equally to this paper. Funding: This research was supported by the Beijing Academy of Agriculture and Forestry Foundation, China (KYCX202305, QNJJ202131, and KJCX20230214). References: Qian H.Q., et al. 2023. J Ethnopharmacol. 303. Zheng Y., et al. 2022. Arch Virol. 167: 2099-2102. Kumar et al. 2016. Mol Biol Evol. 33: 1870-1874.
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To address the fuzzy reconstruction effect on distant objects in unbounded scenes and the difficulty in feature matching caused by the thin structure of power lines in images, this paper proposes a novel image-based method for the reconstruction of power transmission lines (PTLs). The dataset used in this paper comprises PTL progressive motion sequence datasets, constructed by a visual acquisition system carried by a developed Flying-walking Power Line Inspection Robot (FPLIR). This system captures close-distance and continuous images of power lines. The study introduces PL-NeRF, that is, an enhanced method based on the Neural Radiance Fields (NeRF) method for reconstructing PTLs. The highlights of PL-NeRF include (1) compressing the unbounded scene of PTLs by exploiting the spatial compression of normal L∞; (2) encoding the direction and position of the sample points through Integrated Position Encoding (IPE) and Hash Encoding (HE), respectively. Compared to existing methods, the proposed method demonstrates good performance in 3D reconstruction, with fidelity indicators of PSNR = 29, SSIM = 0.871, and LPIPS = 0.087. Experimental results highlight that the combination of PL-NeRF with progressive motion sequence images ensures the integrity and continuity of PTLs, improving the efficiency and accuracy of image-based reconstructions. In the future, this method could be widely applied for efficient and accurate 3D reconstruction and inspection of PTLs, providing a strong foundation for automated monitoring of transmission corridors and digital power engineering.
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BACKGROUND: Poly γ-glutamic acid (γ-PGA) is a promising biopolymer for various applications. For glutamic acid-independent strains, the titer of γ-PGA is too low to meet the industrial demand. In this study, we isolated a novel γ-PGA-producing strain, Bacillus tequilensis BL01, and multiple genetic engineering strategies were implemented to improve γ-PGA production. RESULTS: First, the one-factor-at-a-time method was used to investigate the influence of carbon and nitrogen sources and temperature on γ-PGA production. The optimal sources of carbon and nitrogen were sucrose and (NH4)2SO4 at 37 °C, respectively. Second, the sucA, gudB, pgdS, and ggt genes were knocked out simultaneously, which increased the titer of γ-PGA by 1.75 times. Then, the titer of γ-PGA increased to 18.0 ± 0.3 g/L by co-overexpression of the citZ and pyk genes in the mutant strain. Furthermore, the γ-PGA titer reached 25.3 ± 0.8 g/L with a productivity of 0.84 g/L/h and a yield of 1.50 g of γ-PGA/g of citric acid in fed-batch fermentation. It should be noted that this study enables the synthesis of low (1.84 × 105 Da) and high (2.06 × 106 Da) molecular weight of γ-PGA by BL01 and the engineering strain. CONCLUSION: The application of recently published strategies to successfully improve γ-PGA production for the new strain B. tequilensis BL01 is reported. The titer of γ-PGA increased 2.17-fold and 1.32-fold compared with that of the wild type strain in the flask and 5 L fermenter. The strain shows excellent promise as a γ-PGA producer compared with previous studies. Meanwhile, different molecular weights of γ-PGA were obtained, enhancing the scope of application in industry.
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Ácido Cítrico , Ácido Glutámico , Ácido Glutámico/metabolismo , Ácido Poliglutámico , Fermentación , Ingeniería Metabólica/métodos , Carbono , NitrógenoRESUMEN
A three-dimensional (3D) mesoporous material with an atomically precise structure, Ti16Pb5O16(C6H5CO2)2(OCH3)40 (Ti16Pb5), comprised of a novel high-nuclearity Pb-doped titanium oxide cluster (TOC), was synthesized. Ti16Pb5 exhibited a surface area of 45 m2 g-1 and a pore diameter of 3.5 nm. It exhibited an uptake capacity of I2 of ≤2.2 g g-1 in vapor, and the performance was maintained after seven uptake-release cycles. Ti16Pb5 also showed a high adsorption ratio and capacity (93% and 3.1 g g-1) in hexane. The characterization data, including Fourier transform infrared, Raman, and powder X-ray diffraction, suggested the lattice structure of Ti16Pb5 was rigid and I2 was accommodated in the pores of Ti16Pb5. To the best of our knowledge, this is the first example of using a TOC in I2 adsorption. In addition, Ti16Pb5 showed excellent activity and recyclability in visible-light degradation of dye pollutants and photocurrent generation. Our structural analysis suggested the alkoxide ligands within the channels of Ti16Pb5 build up a confined polar environment and thereby facilitate I2 accommodation, and meanwhile, the improved performances and stabilities of Ti16Pb5 are correlated with its cluster-based, 3D hierarchical structure.
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The solvothermal reaction of titanium isopropoxide and chromate in the presence of benzoate produced two novel host-guest clusters encapsulating Cs+ or H3O+, (H3O)@Ti7Cr14 and Cs@Ti7Cr14. The most remarkable feature is that the Ti7O7 ring is concentrically embraced by a Cr14O14 ring to form a rigid Ti7Cr14 host. ESI-MS and 133Cs NMR revealed that the overall framework structures are preserved, whereas the benzoate ligands on the two clusters may be labile in solutions. Both (H3O)@Ti7Cr14 and Cs@Ti7Cr14 exhibit good UV-vis light-responsive properties and photocatalytic activities, with absorption edges extending up to 780 nm. Cs@Ti7Cr14 is an effective visible-light-responsive photocatalyst in both the heterogeneous methylene dye degradation and homogeneous CO2 cycloaddition reaction under mild conditions like room temperature and 1 bar of CO2. According to the mechanism studies, Cs+, as a rigid guest, can significantly improve the photogenerated charge separation efficiency of the Ti7Cr14 host, thereby improving its interface charge separation properties, photocurrent, and photocatalytic activities. Our findings not only provide new members of heterometallic titanium oxide clusters to enrich the metal oxide cluster family but also open up new possibilities for their photoresponses, which may play an important role in solar energy harvesting for sustainable chemistry.
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In this study, biocathode system coupled with different co-metabolism conditions (NaAc, glucose and NaHCO3) were developed to degrade quinolones enrofloxacin (ENR) due to its poorly metabolization, easily accumulation and potential toxicity. Simultaneously, ENR reduction kinetic rate constant in NaAc-fed, glucose-fed and NaHCO3-fed biocathodes, and sole biocathode were increased by 343.62%, 320.46%, 189.19% and 130.88% when compared with that of abiotic cathode when the operational time and ENR concentration were set to 48 h and 25 mg/L. In addition, transformation pathways of ENR revealed pathway II were dominantly occurred in NaAc- and glucose-fed biocathode while pathway IV acting as key metabolic process were shown in NaHCO3-fed biocathode. Moreover, 16S rRNA high-throughput sequencing analysis indicated that biocathodic communities were sensitive to switch-over of carbon source, namely Delftia and Bosea as organohalide-respiring bacteria (OHRB) were abundant in NaAc- and glucose-fed biocathodes while Mesotoga and Syntrophorhabdus that responsible for benzoyl-CoA metabolic process were enriched in NaHCO3-fed biocathode. Overall, this study could unravel the underlying relationship between biocathode degradation pattern of ENR and different co-metabolism conditions, and further offer valuable scientific information on treating refractory quinolones antibiotics via green bioelectrochemical method.
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Bacterias , Glucosa , Bacterias/genética , Electrodos , Enrofloxacina , ARN Ribosómico 16S/genéticaRESUMEN
[2]Catenane, [2]rotaxane, and [2]pseudorotaxane based on a cyclic titanium oxide cluster, [Ti8O8(SO4)16]16- (Ti8), and cyclic/linear alkylammonium cations are reported. Their syntheses, structures, spectroscopy, and stability in water were studied. These molecules were synthesized from and remained intact upon redissolution in acidic water. Hence, the cluster Ti8 is a promising metal oxide ring that can be used as an inorganic analogue of crown ether to assemble inorganic-organic hybrid mechanical interlocked supramolecular assemblies in water.
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Pseudorabies virus (PRV) is known to cause severe encephalitis in juvenile pigs and various non-native hosts; recent evidences suggest that PRV might cause encephalitis in humans. In a multicenter cohort study in China, next-generation sequencing of cerebrospinal fluid (CSF) was performed to detect pathogens in all patients with clinically suspected central nervous system infections. This study involved all the patients whose CSF samples were positive for PRV-DNA; their clinical features were evaluated, and species-specific PCR and serological tests were sequentially applied for validation. Among the 472 patients tested from June 1, 2016, to December 1, 2018, six were positive for PRV-DNA, which were partially validated by PCR and serological tests. Additionally, we retrospectively examined another case with similar clinical and neuroimaging appearance and detected the presence of PRV-DNA. These patients had similar clinical manifestations, including a rapid progression of panencephalitis, and similar neuroimaging features of symmetric lesions in the basal ganglia and bilateral hemispheres. Six of the patients were engaged in occupations connected with swine production. PRV infection should be suspected in patients with rapidly progressive panencephalitis and characteristic neuroimaging features, especially with exposure to swine.
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Ganglios Basales/patología , Cerebro/patología , ADN Viral/genética , Encefalitis Viral/patología , Herpesvirus Suido 1/genética , Carne/virología , Seudorrabia/patología , Adulto , Animales , Anticuerpos Antivirales/líquido cefalorraquídeo , Ganglios Basales/diagnóstico por imagen , Ganglios Basales/virología , Cerebro/diagnóstico por imagen , Cerebro/virología , China , ADN Viral/líquido cefalorraquídeo , Encefalitis Viral/líquido cefalorraquídeo , Encefalitis Viral/diagnóstico , Encefalitis Viral/virología , Femenino , Herpesvirus Suido 1/crecimiento & desarrollo , Herpesvirus Suido 1/patogenicidad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Seudorrabia/líquido cefalorraquídeo , Seudorrabia/diagnóstico , Seudorrabia/virología , PorcinosRESUMEN
The genus Izhakiella was established and designated as a member of the family Enterobacteriaceae in 2016. Although the taxonomical classification of most members in this family has been relatively resolved after two reclassifications in 2016 and 2017, the classification of the genus Izhakiella remains ambiguous. In this study, a polyphasic approach was used to provide evidence supporting the fact that the genus Izhakiella should no longer be considered a member of Enterobacteriaceae and proposes its reclassification into the family Erwiniaceae. The phylogenetic tree of type species in the families Enterobacteriaceae and Erwiniaceae based on the sequences of the 16S rRNA gene, rpoB housekeeping gene, and the whole-genome comprising the 92 core genes revealed that the genus Izhakiella forms a phylogenetic lineage within the family Erwiniaceae. The average nucleotide identity (ANI) value of the type species with genus Izhakiella was found to be higher for the family Erwiniaceae than that for the family Enterobacteriaceae. Notably, 12 conserved signature indels (CSIs) that are exclusively shared among the Erwiniaceae clade members were found in the type strains of the genus Izhakiella. Based on these analyses, this study suggests the reclassification of I. capsodis and I. australiensis into the family Erwiniaceae.
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Enterobacteriaceae/clasificación , Gammaproteobacteria/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Genómica , Mutación INDEL , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Poly-γ-glutamic acid (γ-PGA) is a promising biopolymer and has been applied in many fields. Bacillus siamensis SB1001 was a newly isolated poly-γ-glutamic acid producer with sucrose as its optimal carbon source. To improve the utilization of carbon source, and then molasses can be effectively used for γ-PGA production, 60cobalt gamma rays was used to mutate the genes of B. siamensis SB1001. RESULTS: Bacillus siamensis IR10 was screened for the production of γ-PGA from untreated molasses. In batch fermentation, 17.86 ± 0.97 g/L γ-PGA was obtained after 15 h, which is 52.51% higher than that of its parent strain. Fed-batch fermentation was performed to further improve the yield of γ-PGA with untreated molasses, yielding 41.40 ± 2.01 g/L of γ-PGA with a productivity of 1.73 ± 0.08 g/L/h. An average γ-PGA productivity of 1.85 g/L/h was achieved in the repeated fed-batch fermentation. This is the first report of such a high γ-PGA productivity. The analysis of the enzyme activities showed that they were affected by the carbon sources, enhanced ICDH and GDH, and decreased ODHC, which are important for γ-PGA production. CONCLUSION: These results suggest that untreated molasses can be used for economical and industrial-scale production of γ-PGA by B. siamensis IR10.
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Bacillus/metabolismo , Melaza , Ácido Poliglutámico/análogos & derivados , Bacillus/genética , Carbono/metabolismo , Fermentación , Microbiología Industrial , Ácido Poliglutámico/biosíntesis , Sacarosa/metabolismoRESUMEN
BACKGROUND: 1,3-propanediol (1,3-PDO) is the most widely studied value-added product that can be produced by feeding glycerol to bacteria, including Lactobacillus sp. However, previous research reported that L. reuteri only produced small amounts and had low productivity of 1,3-PDO. It is urgent to develop procedures that improve the production and productivity of 1,3-PDO. RESULTS: We identified a novel L. reuteri CH53 isolate that efficiently converted glycerol into 1,3-PDO, and performed batch co-fermentation with glycerol and glucose to evaluate its production of 1,3-PDO and other products. We optimized the fermentation conditions and nitrogen sources to increase the productivity. Fed-batch fermentation using corn steep liquor (CSL) as a replacement for beef extract led to 1,3-PDO production (68.32 ± 0.84 g/L) and productivity (1.27 ± 0.02 g/L/h) at optimized conditions (unaerated and 100 rpm). When CSL was used as an alternative nitrogen source, the activity of the vitamin B12-dependent glycerol dehydratase (dhaB) and 1,3-propanediol oxidoreductase (dhaT) increased. Also, the productivity and yield of 1,3-PDO increased as well. These results showed the highest productivity in Lactobacillus species. In addition, hurdle to 1,3-PDO production in this strain were identified via analysis of the half-maximal inhibitory concentration for growth (IC50) of numerous substrates and metabolites. CONCLUSIONS: We used CSL as a low-cost nitrogen source to replace beef extract for 1,3-PDO production in L. reuteri CH53. These cells efficiently utilized crude glycerol and CSL to produce 1,3-PDO. This strain has great promise for the production of 1,3-PDO because it is generally recognized as safe (GRAS) and non-pathogenic. Also, this strain has high productivity and high conversion yield.
Asunto(s)
Limosilactobacillus reuteri/metabolismo , Glicoles de Propileno/metabolismo , Fermentación , Glicerol/metabolismo , Jarabe de Maíz Alto en Fructosa/metabolismo , Microbiología Industrial/métodosRESUMEN
Bacillus subtilis naturally produces large amounts of 2,3-butanediol (2,3-BD) as a main by-product during poly-γ-glutamic acid (γ-PGA) production. 2,3-BD is a promising platform chemical in various industries, and co-production of the two chemicals has great economic benefits. Co-production of γ-PGA and 2,3-BD by a newly isolated B. subtilis CS13 was investigated here. The fermentation medium and culture parameters of the process were optimized using statistical methods. It was observed that sucrose, L-glutamic acid, ammonium citrate, and MgSO4·7H2O were favorable for γ-PGA and 2,3-BD co-production at culture pH of 6.5 and 37 °C. An optimal medium composed of 119.8 g/L sucrose, 48.8 g/L L-glutamic acid, 21.1 g/L ammonium citrate, and 3.2 g/L MgSO4·7H2O was obtained by response surface methodology (RSM). The results show that the titers of γ-PGA and 2,3-BD reached 27.8 ± 0.9 g/L at 24 h and 57.1 ± 1.3 g/L at 84 h with the optimized medium, respectively. γ-PGA and 2,3-BD production by B. subtilis CS13 was significantly enhanced in fed-batch fermentations. γ-PGA (36.5 ± 1.1 g/L, productivity of 1.22 ± 0.04 g/L/h) and 2,3-BD concentrations (119.6 ± 2.8 g/L, productivity of 2.49 ± 0.66 g/L/h) were obtained in the optimized medium with feeding sucrose. The co-production of 2,3-BD and γ-PGA provides a new perspective for industrial production of γ-PGA and 2,3-BD. Key points ⢠A strategy for co-production of γ-PGA and 2,3-BD was developed. ⢠The culture parameters for the co-production of γ-PGA and 2,3-BD were studied. ⢠RSM was used to optimize the medium for γ-PGA and 2,3-BD co-production. ⢠36.5 g/L γ-PGA and 119.6 g/L 2,3-BD were obtained from the optimum medium in fed-batch fermentation.