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1.
PLoS Pathog ; 19(10): e1011740, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37851691

RESUMO

The Toll receptor signaling pathway is an important innate immune response of insects to pathogen infection; its extracellular signal transduction involves serine protease cascade activation. However, excessive or constitutive activation of the Toll pathway can be detrimental. Hence, the balance between activation and inhibition of the extracellular protease cascade must be tightly regulated to achieve favorable outcomes. Previous studies have shown that serpins-serine protease inhibitors-negatively regulate insect innate immunity by inhibiting extracellular protease cascade signaling. Although the roles of serpins in insect innate immunity are well described, the physiological mechanisms underlying their synergistic effects remain poorly understand. Here, we characterize the molecular mechanism by which serpin-1a and serpin-6 synergistically maintain immune homeostasis of the silkworm Toll pathway under physiological and pathological conditions. Through in vitro biochemical assays and in vivo bioassays, we demonstrate that clip-domain serine protease 2 (CLIP2), as the Toll cascade-activating terminal protease, is responsible for processing proSpätzle1 to induce the expression of antimicrobial peptides. Further biochemical and genetic analyses indicate that constitutively expressed serpin-1a and inducible serpin-6 synergistically target CLIP2 to maintain homeostasis of the silkworm Toll pathway under physiological and pathological conditions. Taken together, this study provides new insights into the precise regulation of Toll cascade activation signals in insect innate immune responses and highlights the importance and complexity of insect immune homeostasis regulation.


Assuntos
Bombyx , Serpinas , Animais , Serpinas/metabolismo , Bombyx/genética , Proteínas de Insetos/metabolismo , Serina Proteases/metabolismo , Homeostase
2.
Anim Biotechnol ; 35(1): 2337760, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38656923

RESUMO

Although the knee joint (KNJ) and temporomandibular joint (TMJ) all belong to the synovial joint, there are many differences in developmental origin, joint structure and articular cartilage type. Studies of joint development in embryos have been performed, mainly using poultry and rodents. However, KNJ and TMJ in poultry and rodents differ from those in humans in several ways. Very little work has been done on the embryonic development of KNJ and TMJ in large mammals. Several studies have shown that pigs are ideal animals for embryonic development research. Embryonic day 30 (E30), E35, E45, E55, E75, E90, Postnatal day 0 (P0) and Postnatal day 30 (P30) embryos/fetuses from the pigs were used for this study. The results showed that KNJ develops earlier than TMJ. Only one mesenchymal condensate of KNJ is formed on E30, while two mesenchymal condensates of TMJ are present on E35. All structures of KNJ and TMJ were formed on E45. The growth plate of KNJ begins to develop on E45 and becomes more pronounced from E55 to P30. From E75 to E90, more and more vascular-rich cartilage canals form in the cartilage regions of both joints. The cartilaginous canal of the TMJ divides the condyle into sections along the longitudinal axis of the condyle. This arrangement of cartilaginous canal was not found in the KNJ. The chondrification of KNJ precedes that of TMJ. Ossification of the knee condyle occurs gradually from the middle to the periphery, while that of the TMJ occurs gradually from the base of the mandibular condyle. In the KNJ, the ossification of the articular condyle is evident from P0 to P30, and the growth plate is completely formed on P30. In the TMJ, the cartilage layer of condyle becomes thinner from P0 to P30. There is no growth plate formation in TMJ during its entire development. There is no growth plate formation in the TMJ throughout its development. The condyle may be the developmental center of the TMJ. The chondrocytes and hypertrophic chondrocytes of the growth plate are densely arranged. The condylar chondrocytes of TMJ are scattered, while the hypertrophic chondrocytes are arranged. Embryonic development of KNJ and TMJ in pigs is an important bridge for translating the results of rodent studies to medical applications.


Assuntos
Articulação do Joelho , Articulação Temporomandibular , Animais , Suínos/embriologia , Articulação Temporomandibular/embriologia , Articulação Temporomandibular/crescimento & desenvolvimento , Articulação do Joelho/embriologia , Articulação do Joelho/crescimento & desenvolvimento , Cartilagem Articular/embriologia , Cartilagem Articular/crescimento & desenvolvimento , Feminino , Desenvolvimento Embrionário/fisiologia , Embrião de Mamíferos
3.
Plant J ; 109(3): 541-554, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34773305

RESUMO

Insulators characterized in Drosophila and mammals have been shown to play a key role in the restriction of promiscuous enhancer-promoter interactions, as well as reshaping the topological landscape of chromosomes. Yet the role of insulators in plants remains poorly understood, in large part because of a lack of well-characterized insulators and binding factor(s). In this study, we isolated a 1.2-kb RS2-9 insulator from the Oryza sativa (rice) genome that can, when interposed between an enhancer and promoter, efficiently block the activation function of both constitutive and floral organ-specific enhancers in transgenic Arabidopsis and Nicotiana tabacum (tobacco). In the rice genome, the genes flanking RS2-9 exhibit an absence of mutual transcriptional interactions, as well as a lack of histone modification spread. We further determined that O. sativa Homeobox 1 (OSH1) bound two regions of RS2-9, as well as over 50 000 additional sites in the rice genome, the majority of which resided in intergenic regions. Mutation of one of the two OSH1-binding sites in RS2-9 impaired insulation activity by up to 60%, whereas the mutation of both binding sites virtually abolished insulator function. We also demonstrated that OSH1 binding sites were associated with 72% of the boundaries of topologically associated domains (TADs) identified in the rice genome, which is comparable to the 77% of TAD boundaries bound by the insulator CCCTC-binding factor (CTCF) in mammals. Taken together, our findings indicate that OSH1-RS2-9 acts as a true insulator in plants, and highlight a potential role for OSH1 in gene insulation and topological organization in plant genomes.


Assuntos
Elementos Facilitadores Genéticos/fisiologia , Oryza/genética , Oryza/metabolismo , Regiões Promotoras Genéticas/fisiologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fatores de Transcrição/fisiologia
4.
Trends Genet ; 36(11): 810-813, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32828551

RESUMO

CRISPR/Cas9 is a versatile tool for plant gene function studies and crop improvement. However, traditional CRISPR/Cas9-mediated genome editing requires plant tissue culture that is both time-consuming and genotype-dependent. Ma et al. recently reported a novel virus-based method for delivering CRISPR/Cas9 into plant cells, and this should further expand the application of CRISPR/Cas9-mediated genome editing.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Genoma de Planta , Plantas/genética
5.
Nano Lett ; 22(5): 2112-2119, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226511

RESUMO

Transition metal dichalcogenide monolayers exhibit ultrahigh surface sensitivity since they expose all atoms to the surface and thereby influence their optoelectronic properties. Here, we report an intriguing lightening of the photoluminescence (PL) from the edge to the interior over time in the WS2 monolayers grown by physical vapor deposition method, with the whole monolayer brightened eventually. Comprehensive optical studies reveal that the PL enhancement arises from the p doping induced by oxygen adsorption. First-principles calculations unveil that the dissociation of chemisorbed oxygen molecule plays a significant role; i.e., the dissociation at one site can largely promote the dissociation at a nearby site, facilitating the photoluminescence lightening. In addition, we further manipulate such PL brightening rate by controlling the oxygen concentration and the temperature. The presented results uncover the extraordinary surface chemistry and related mechanism in WS2 monolayers, which deepens our insight into their unique PL evolution behavior.

6.
Int J Mol Sci ; 24(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175648

RESUMO

Lipoxygenase (EC1.13.11.12, LOX) has been potentially used in the food industry for food quality improvement. However, the low activity, poor thermal stability, narrow range of pH stability, as well as undesirable isoenzymes and off-flavors, have hampered the application of current commercial LOX. In this study, a putative mini-lipoxygenase gene from cyanobacteria, Nostoc sphaeroides (NsLOX), was cloned and expressed in E. coli BL21. NsLOX displayed only 26.62% structural identity with the reported LOX from Cyanothece sp., indicating it as a novel LOX. The purified NsLOX showed the maximum activity at pH 8.0 and 15 °C, with superior stability at a pH range from 6.0 to 13.0, retaining about 40% activity at 40 °C for 90 min. Notably, NsLOX exhibited the highest specific activity of 78,080 U/mg towards linoleic acid (LA), and the kinetic parameters-Km, kcat, and kcat/Km-attain values of 19.46 µM, 9199.75 s-1, and 473.85 µM-1 s-1, respectively. Moreover, the activity of NsLOX was obviously activated by Ca2+, but it was completely inhibited by Zn2+ and Cu2+. Finally, NsLOX was supplied in steamed bread and contributed even better improved bread quality than the commercial LOX. These results suggest NsLOX as a promising substitute of current commercial LOX for application in the food industry.


Assuntos
Pão , Lipoxigenase , Lipoxigenase/genética , Escherichia coli/genética , Melhoria de Qualidade
7.
Angew Chem Int Ed Engl ; 62(44): e202309111, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37698233

RESUMO

Recently, the application of computational tools to the rational design of catalysts has received considerable attention, but progress has been limited by the reliance on databases and because mechanistic data have been almost neglected. Herein, we report a new strategy for catalyst design, designated catalyst-oriented design based on elementary reactions (CODER), which fully utilizes mechanistic data, combines the strengths of computational tools and researcher experience. CODER enabled the development of extremely efficient Pd catalysts for C-N coupling, which markedly improved the efficiency of the synthesis of widely used triarylamine optoelectronic materials by enhancing the turnover numbers (up to 340000) to 1-3 orders of magnitude towards literature values.

8.
BMC Microbiol ; 22(1): 260, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309654

RESUMO

BACKGROUND: Female reproductive tract infection (RTI) is the common source of varied diseases, especially as an important risk factor for pregnancy outcomes, therefore the rapid, accurate and simultaneous detection of multiple pathogens is in urgent need for assisting the diagnosis and treatment of RTI in pregnant women. Streptococcus agalactiae (S. agalactiae), Enterococcus faecalis (E. faecalis), Gardnerella vaginalis (G. vaginalis), Candida albicans (C. albicans) and Chlamydia trachomatis (C. trachomatis) are five main pathogens in lower genital tract with high risk, serious consequences and clinical demands. The combination of loop-mediated isothermal amplification (LAMP) and microfluidic technology was used to develop the LAMP-microfluidic chip for rapid, simple, sensitive and simultaneous detection of the five target pathogens above. RESULTS: Standard strains and clinical isolates were used for the establishment of the novel LAMP method in tube and LAMP-microfluidic chip, followed by the chip detection on 103 clinical samples and PCR verification partially. The sensitivities of LAMP of S. agalactiae, E. faecalis, G. vaginalis, and C. albicans in tube were 22.0, 76.0, 13.2, 1.11 CFU/µL, respectively, and C. trachomatis was 41.3 copies/µL; on LAMP-microfluidic chip they were 260, 154, 3.9 and 7.53 CFU/µL, respectively, and C. trachomatis was 120 copies/µL. The positive coincidence rates of clinical stains in tube and on chip experiments were 100%. Compared with the classic culture method performed in hospitals, the positive coincidence rate of the 103 clinical samples detected by LAMP-microfluidic chip were 100%. For the six inconsistent ones, including four G. vaginalis and two C. albicans positive samples tested by LAMP-microfluidic chip and verified by PCR were negative by culturing method in hospitals, indicating the lack of efficient detection by the classic culturing method. CONCLUSION: Our study suggested that the LAMP-microfluidic chips could simultaneously, efficiently, and accurately detect multiple main pathogens, including S. agalactiae, E. faecalis, G. vaginalis, C. albicans and C. trachomatis, in clinical samples of female RTI to give a great clinical value. Accordingly, this novel method has the potential to provide a valuable reference for female RTI screening and early diagnosis during pregnancy.


Assuntos
Microfluídica , Infecções do Sistema Genital , Feminino , Humanos , Gravidez , Sensibilidade e Especificidade , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase , Chlamydia trachomatis/genética
9.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232419

RESUMO

Surfactin from Bacillus amyloliquefaciens fmb50 was utilized to treat mice with type 2 diabetes (T2DM) induced by a high-fat diet/streptozotocin (HFD/STZ). Our group's earlier research indicated that surfactin could lower blood glucose and mitigate liver dysfunction to further improve HFD/STZ-induced T2DM through modulating intestinal microbiota. Thus, we further investigated the effects of surfactin on the pancreas and colon in mice with T2DM to elucidate the detailed mechanism. In the present study, mice with HFD/STZ-induced T2DM had their pancreatic and colon inflammation, oxidative stress, and endoplasmic reticulum stress (ERS) reduced when given oral surfactin at a dose of 80 mg/kg body weight. According to further research, surfactin also improved glucose metabolism by activating the phosphatidylinositol kinase (PI3K)/protein kinase B (Akt) signaling pathway, further protecting islets ß-cell, promoting insulin secretion, inhibiting glucagon release and mitigating pancreas dysfunction. Additionally, after surfactin treatment, the colon levels of the tight junction proteins Occludin and Claudin-1 of T2DM mice were considerably increased by 130.64% and by 36.40%, respectively. These findings revealed that surfactin not only ameliorated HFD/STZ-induced pancreas inflammation and dysfunction and preserved intestinal barrier dysfunction and gut microbiota homeostasis but also enhanced insulin sensitivity and glucose homeostasis in T2DM mice. Finally, in the further experiment, we were able to demonstrate that early surfactin intervention might delay the development of T2DM caused by HFD/STZ, according to critical biochemical parameters in serum.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Glicemia/metabolismo , Claudina-1 , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucagon , Glucose/metabolismo , Inflamação/complicações , Inflamação/tratamento farmacológico , Camundongos , Ocludina , Pâncreas/metabolismo , Hormônios Pancreáticos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositóis/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estreptozocina
10.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077061

RESUMO

Low catalytic activity is a key factor limiting the widespread application of type II L-asparaginase (ASNase) in the food and pharmaceutical industries. In this study, smart libraries were constructed by semi-rational design to improve the catalytic activity of type II ASNase from Bacillus licheniformis. Mutants with greatly enhanced catalytic efficiency were screened by saturation mutations and combinatorial mutations. A quintuple mutant ILRAC was ultimately obtained with specific activity of 841.62 IU/mg and kcat/Km of 537.15 min-1·mM-1, which were 4.24-fold and 6.32-fold more than those of wild-type ASNase. The highest specific activity and kcat/Km were firstly reported in type II ASNase from Bacillus licheniformis. Additionally, enhanced pH stability and superior thermostability were both achieved in mutant ILRAC. Meanwhile, structural alignment and molecular dynamic simulation demonstrated that high structure stability and strong substrate binding were beneficial for the improved thermal stability and enzymatic activity of mutant ILRAC. This is the first time that enzymatic activity of type II ASNase from Bacillus licheniformis has been enhanced by the semi-rational approach, and results provide new insights into enzymatic modification of L-asparaginase for industrial applications.


Assuntos
Asparaginase , Bacillus licheniformis , Asparaginase/química , Asparaginase/genética , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Catálise , Simulação de Dinâmica Molecular
11.
Pharm Biol ; 60(1): 931-948, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35587352

RESUMO

CONTEXT: Developing effective drugs to treat myocardial ischaemia-reperfusion (MI/R) injury is imperative. Traditional Chinese medicines (TCMs) have had considerable success in the treatment of cardiovascular diseases. Elucidating the mechanisms by which TCMs improve MI/R injury can supplement the literature on MI/R prevention and treatment. OBJECTIVE: To summarise TCMs and their main protective mechanisms against MI/R injury reported over the past 40 years. METHODS: Relevant literature published between 1980 and 2020 in Chinese and English was retrieved from the Web of Science, PubMed, SpringerLink, PubMed Central, Scopus, and Chinese National Knowledge Infrastructure (CNKI) databases. Search terms included 'medicinal plants', 'myocardial ischaemia reperfusion injury', 'Chinese medicine prescriptions', 'mechanisms', 'prevention', 'treatment' and 'protection'. For inclusion in the analysis, medicinal plants had to be searchable in the China Medical Information Platform and Plant Database. RESULTS: We found 71 medicinal species (from 40 families) that have been used to prevent MI/R injury, of which Compositae species (8 species) and Leguminosae species (7 species) made up the majority. Most of the effects associated with these plants are described as antioxidant and anti-inflammatory. Furthermore, we summarised 18 kinds of Chinese compound prescriptions, including the compound Danshen tablet and Baoxin pill, which mainly reduce oxidative stress and regulate mitochondrial energy metabolism. DISCUSSION AND CONCLUSIONS: We summarised TCMs that protect against MI/R injury and their pharmacological mechanisms. This in-depth explanation of the roles of TCMs in MI/R injury protection provides a theoretical basis for the research and development of TCM-based treatment drugs.


Assuntos
Medicamentos de Ervas Chinesas , Traumatismo por Reperfusão Miocárdica , Plantas Medicinais , Anti-Inflamatórios/uso terapêutico , China , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle
12.
Appl Opt ; 60(3): 763-772, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33690451

RESUMO

This paper presents a real-time measurement method for the skin temperature of the human arm. In this method, the air temperature close to the arm skin is measured via large lateral shearing interferometry, thus avoiding the possible influences of the different physical characteristics of different people, while maintaining the advantages of optical measurement, including its noncontact, noninvasive, and rapid features. The method captures the real-time fringe patterns generated using a parallel-sided plate when a collimated laser light beam transfers through the air surrounding the arm to be measured. Additionally, the phase difference distribution caused by the temperature difference is calculated in combination with the background fringe patterns. The phase difference in the light close to the arm skin is then estimated via a linear fitting method. Accordingly, based on the size parameters of the arm cross section and the ambient temperature monitored in real time, the air temperature close to the arm skin, which is considered equal to the arm skin temperature, is determined while considering the heat conduction effect. Experimental measurements of the temperature of human arm skin were conducted using the proposed method, and the axillary temperatures of the same person before and after the experiments were also measured using an electronic thermometer and a mercury thermometer. Good agreements were found, verifying the reliability of the proposed method. Moreover, based on this method, the possibility for the construction of a real-time body temperature measurement system is also discussed.


Assuntos
Interferometria/instrumentação , Monitorização Fisiológica/instrumentação , Temperatura Cutânea , Braço , Simulação por Computador , Humanos , Luz , Modelos Químicos , Reprodutibilidade dos Testes , Pele , Termômetros
13.
BMC Musculoskelet Disord ; 22(1): 345, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33845826

RESUMO

BACKGROUND: In the late stage of spinal tuberculosis, the bony destruction and vertebral collapse often leads to significant kyphosis, presenting clinically as a painful gibbus deformity, with increased instability, vertebral body translations and increased risk of neurologic involvement. Spinal osteotomy is thought to be suitable for most patients with severe rigid kyphosis. The aim of this study was to evaluate the efficacy of transpedicular bi-vertebrae osteotomy technique in the patients with Pott's kyphosis and other post-tubercular spinal deformity. METHODS: Between January 2012 and December 2015, 18 patients with post-tubercular spinal deformity underwent the transpedicular bi-vertebrae wedge osteotomy, with a minimum follow up of 27.0 months. Preoperative and postoperative kyphotic angle, sagittal plane parameters (TK for thoracic deformity, TLK for thoracolumbar and LL for lumbar deformity) and sagittal vertical axis (SVA) were measured. Oswestry Disability Index (ODI), Visual analog scale (VAS) and modified American Spinal Injury Association grading (ASIA) of preoperative and final follow-up were documented and compared. RESULTS: The average operation time was 305 minutes (range, 200-430 minutes) with a mean intraoperative blood loss of 425 mL (range, 200-700 mL). The kyphotic angles decreased from 80.3° (range, 28.5°-130.8°) preoperatively to 26.1° (range, 7.0°-63.3°) at the final follow-up (P<0.01). The mean VAS score was reduced from preoperative 5.2(range, 2-9) to 0.9(range, 0-2, P<0.01) and the ODI improved from 55.3% (range, 46%-76%) to 6.3% (range, 2%-18%, P<0.01). At final follow-up, there was radiographic evidence of solid fusion at the osteotomy site and fixed segments in all patients. Neurological function improved from ASIA scale D to E in 7 patients, C to D in 3 patients. CONCLUSIONS: Our results suggest that transpedicular bi-vertebrae wedge osteotomy is a safe and effective treatment option for post-tubercular spinal deformity. This technique achieves satisfying correction and fusion rates with adequate decompression of neurological elements.


Assuntos
Cifose , Fusão Vertebral , Humanos , Cifose/diagnóstico por imagem , Cifose/etiologia , Cifose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Osteotomia , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Resultado do Tratamento
14.
Molecules ; 26(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34833997

RESUMO

The soft rot disease caused by Rhizopus stolonifer is an important disease in cherry tomato fruit. In this study, the effect of iturin A on soft rot of cherry tomato and its influence on the storage quality of cherry tomato fruit were investigated. The results showed that 512 µg/mL of iturin A could effectively inhibit the incidence of soft rot of cherry tomato fruit. It was found that iturin A could induce the activity of resistance-related enzymes including phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), glucanase (GLU), and chitinase (CHI), and active oxygen-related enzymes including ascorbate peroxidases (APX), superoxide dismutases (SOD), catalases (CAT), and glutathione reductase (GR) of cherry tomato fruit. In addition, iturin A treatment could slow down the weight loss of cherry tomato and soften the fruit. These results indicated that iturin A could retard the decay and improve the quality of cherry tomato fruit by both the inhibition growth of R. stolonifera and the inducing the resistance.


Assuntos
Resistência a Medicamentos/efeitos dos fármacos , Frutas/metabolismo , Peptídeos Cíclicos/farmacologia , Doenças das Plantas/microbiologia , Raízes de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Frutas/microbiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Proteínas de Plantas/biossíntese , Raízes de Plantas/microbiologia , Rhizopus/crescimento & desenvolvimento
15.
Funct Integr Genomics ; 20(5): 657-668, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32483723

RESUMO

AZC_2928 gene (GenBank accession no. BAF88926.1) of Azorhizobium caulinodans ORS571 has sequence homology to 2,3-aminomutases. However, its function is unknown. In this study, we are for the first time to knock out the gene completely in A. caulinodans ORS571 using the current advanced genome editing tool, CRISPR/Cas9. Our results show that the editing efficiency is 34% and AZC_2928 plays an extremely important role in regulating the formation of chemotaxis and biofilm. CRISPR/Cas9 knockout of AZC_2928 (△AZC_2928) significantly enhanced chemotaxis and biofilm formation. Both chemotaxis and biofilm formation play an important role in nitrogen-fixing bacteria and their interaction with their host plants. Interestingly, AZC_2928 did not affect the motility of A. caulinodans ORS571 and the nodulation formation in their natural host plant, Sesbania rostrata. Due to rhizobia needing to form bacteroids for symbiotic nitrogen fixation in mature nodules, AZC_2928 might have a direct influence on nitrogen fixation efficiency rather than the number of nodulations.


Assuntos
Azorhizobium caulinodans/genética , Proteínas de Bactérias/fisiologia , Sistemas CRISPR-Cas , Edição de Genes , Azorhizobium caulinodans/crescimento & desenvolvimento , Azorhizobium caulinodans/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Biofilmes , Quimiotaxia , Técnicas de Inativação de Genes , Genes Bacterianos , Fixação de Nitrogênio , Nodulação , Análise de Sequência de Proteína , Sesbania/microbiologia , Sesbania/fisiologia
16.
J Org Chem ; 85(5): 3508-3516, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31958013

RESUMO

New practical synthesis of 2-amino-1,3-selenazole with transition metal-free multicomponent reaction is reported here. A series of 2-amino-1,3-selenazole derivatives were afforded by the nucleophilic addition of amines to isoselenocyanate formed in situ, followed by Michael addition reaction and aromatization. The products were isolated from moderate to excellent yields.

17.
Inorg Chem ; 59(20): 14796-14806, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-32806018

RESUMO

In this article, we report the design, synthesis, and characterization of a series of cyclometalated iridium(III) polypyridine complexes containing a perfluorobiphenyl (PFBP) moiety [Ir(N^C)2(bpy-PFBP)](PF6) (bpy-PFBP = 4-(S-(perfluoro-(1,1'-biphenyl)-4-yl)-N-mercaptoethylaminocarbonyloxymethyl)-4'-methyl-2,2'-bipyridine; HN^C = 2-phenylpyridine (Hppy) (1a), 2-(4-hydroxymethylphenyl)pyridine (Hppy-CH2OH) (2a), 2-((1,1'-biphenyl)-4-yl)pyridine (Hpppy) (3a), 2-((4'-hydroxymethyl-1,1'-biphenyl)-4-yl)pyridine (Hpppy-CH2OH) (4a), 2-phenylquinoline (Hpq) (5a), 2-(4-hydroxymethylphenyl)quinoline (Hpq-CH2OH) (6a)). Their PFBP-free counterparts [Ir(N^C)2(bpy-C4)](PF6) (bpy-C4 = 4-(N-n-butylaminocarbonyloxymethyl)-4'-methyl-2,2'-bipyridine; HN^C = Hppy (1b), Hppy-CH2OH (2b), Hpppy (3b), Hpppy-CH2OH (4b), Hpq (5b), Hpq-CH2OH (6b)) were also prepared for comparison studies. Upon irradiation, all the complexes displayed intense and long-lived greenish-yellow to orange luminescence in solutions under ambient conditions and in low-temperature alcohol glass. Reactions of the PFBP complexes with peptides containing the FCPF sequence via the π-clamp-mediated cysteine conjugation afforded luminescent peptide conjugates that exhibited rich photophysical properties. Using complex 3a as an example, we demonstrated that the conjugation of complexes to organelle-targeting peptides is an effective means to modulate their intracellular localization behavior, which was further shown to be important to their performance in photodynamic therapy. The results of this work will contribute to the development of photofunctional transition metal complexes as theranostic agents.


Assuntos
Compostos de Bifenilo/farmacologia , Complexos de Coordenação/farmacologia , Substâncias Luminescentes/farmacologia , Piridinas/farmacologia , Radiossensibilizantes/farmacologia , Compostos de Bifenilo/metabolismo , Compostos de Bifenilo/efeitos da radiação , Núcleo Celular/metabolismo , Complexos de Coordenação/metabolismo , Complexos de Coordenação/efeitos da radiação , Retículo Endoplasmático/metabolismo , Células HeLa , Humanos , Irídio/química , Irídio/efeitos da radiação , Luz , Substâncias Luminescentes/metabolismo , Substâncias Luminescentes/efeitos da radiação , Microscopia Confocal , Peptídeos/metabolismo , Peptídeos/farmacologia , Medicina de Precisão , Piridinas/metabolismo , Piridinas/efeitos da radiação , Radiossensibilizantes/metabolismo , Radiossensibilizantes/efeitos da radiação , Oxigênio Singlete/metabolismo
18.
Inorg Chem ; 59(14): 9638-9647, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32479064

RESUMO

Efficient Cs+-Sr2+ separation, highly desirable for radionuclide recovery in medical and industrial applications, was achieved by the ion exchange technique over a novel microporous silver selenidostannate, [NH3CH3]0.5[NH2(CH3)2]0.25Ag1.25SnSe3 (AgSnSe-1). This material was synthesized in deep eutectic solvent (DES), where the alkylammonium cations play significant structure-directing roles in the construction of micropores that allow for selective ion exchange toward Cs+ against Sr2+. The much greater KdCs (1.06 × 104 mL g-1) over KdSr (87.7 mL g-1) contributes to an outstanding separation factor SFCs/Sr of ∼121.4 that is top-ranked among inorganic materials. An ion exchange column filled with AgSnSe-1 exhibits a remarkable separation effect for 10 000 bed volumes of continuous flow, with removal rates of ∼99.9% and ∼0 ± 5.5% for Cs+ and Sr2+, respectively. AgSnSe-1 exhibits excellent ß and γ radiation resistances and a chemical stability over a broad pH range of 1-12. The Se leaching level below the safe guideline value for drinking water highlights the environmental-friendly nature of AgSnSe-1. The high Cs+ exchange performance is almost unaffected by Na+, Mg2+, and Ca2+ cations. The Cs+-laden product AgSnSe-1Cs can be facilely eluted for recycling use, highlighting the great potential of open framework metal selenides in nuclear waste treatment and renewable energy utilization.

19.
Arch Virol ; 165(9): 2083-2086, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32524261

RESUMO

A new virus with sequence similarities to members of the genus Cavemovirus in the family Caulimoviridae was identified in an Epiphyllum hybrid. The complete genome of the virus, tentatively named "epiphyllum virus 4" (EpV-4), was determined to be 7,296 nucleotides long. Its circular genome organization is typical of cavemoviruses, containing four open reading frames. This virus and the two known cavemoviruses share 67-69% and 72-75% overall nucleotide sequence identity in the replicase gene. Phylogenetic analysis placed EpV-4 in a same cluster with the two recognized cavemoviruses. Thus, EpV-4 should be considered a representative of a third species of the genus Cavemovirus. The virus was transmitted by grafting.


Assuntos
Cactaceae/virologia , Caulimoviridae/isolamento & purificação , Doenças das Plantas/virologia , Caulimoviridae/classificação , Caulimoviridae/genética , Genoma Viral , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética
20.
Arch Virol ; 165(9): 2115-2118, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32562074

RESUMO

A new badnavirus was identified in an ornamental camellia tree with yellow mottle symptom. The complete circular double-stranded DNA genome of this virus was found to consist of 8,203 bp. Its genome organization is typical of badnaviruses, containing three open reading frames (ORFs). ORFs 1 and 2 encode putative proteins with unknown functions. ORF3 encodes a large polyprotein that contains almost all of the conserved domains of badnaviruses. The virus shares 55-62% nucleotide sequence identities with other badnaviruses in the RT+RNase H region. Phylogenetic analyses placed it in group I of the genus Badnavirus. Therefore, this virus, which is tentatively named "camellia Lemon Glow virus", should represent a new species of the genus Badnavirus. This virus was found to be present in approximately a quarter of camellia trees tested.


Assuntos
Badnavirus/genética , Badnavirus/isolamento & purificação , Camellia/virologia , Doenças das Plantas/virologia , Badnavirus/classificação , Badnavirus/fisiologia , Genoma Viral , Fases de Leitura Aberta , Filogenia , Proteínas Virais/genética
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