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1.
Plant Cell ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819320

RESUMO

The brassinosteroid (BR) receptor BRASSINOSTEROID-INSENSITIVE 1 (BRI1) plays a critical role in plant growth and development. Although much is known about how BR signaling regulates growth and development in many crop species, the role of StBRI1 in regulating potato (Solanum tuberosum) tuber development is not well understood. To address this question, a series of comprehensive genetic and biochemical methods were applied in this investigation. It was determined that StBRI1 and Solanum tuberosum PLASMA MEMBRANE (PM) PROTON ATPASE2 (PHA2), a PM-localized proton ATPase, play important roles in potato tuber development. The individual overexpression of StBRI1 and PHA2 led to a 22% and 25% increase in tuber yield per plant, respectively. Consistent with the genetic evidence, in vivo interaction analysis using double transgenic lines and PM H+-ATPase activity assays indicated that StBRI1 interacts with the C-terminus of PHA2, which restrains the intramolecular interaction of the PHA2 C-terminus with the PHA2 central loop to attenuate autoinhibition of PM H+-ATPase activity, resulting in increased PHA2 activity. Furthermore, the extent of PM H+-ATPase autoinhibition involving phosphorylation-dependent mechanisms corresponds to phosphorylation of the penultimate Thr residue (Thr-951) in PHA2. These results suggest that StBRI1 phosphorylates PHA2 and enhances its activity, which subsequently promotes tuber development. Altogether, our results uncover a BR-StBRI1-PHA2 module that regulates tuber development and suggest a prospective strategy for improving tuberous crop growth and increasing yield via the cell surface-based BR signaling pathway.

2.
J Am Chem Soc ; 146(17): 11866-11875, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621677

RESUMO

The available methods of chemical synthesis have arguably contributed to the prevalence of aromatic rings, such as benzene, toluene, xylene, or pyridine, in modern pharmaceuticals. Many such sp2-carbon-rich fragments are now easy to synthesize using high-quality cross-coupling reactions that click together an ever-expanding menu of commercially available building blocks, but the products are flat and lipophilic, decreasing their odds of becoming marketed drugs. Converting flat aromatic molecules into saturated analogues with a higher fraction of sp3 carbons could improve their medicinal properties and facilitate the invention of safe, efficacious, metabolically stable, and soluble medicines. In this study, we show that aromatic and heteroaromatic drugs can be readily saturated under exceptionally mild rhodium-catalyzed hydrogenation, acid-mediated reduction, or photocatalyzed-hydrogenation conditions, converting sp2 carbon atoms into sp3 carbon atoms and leading to saturated molecules with improved medicinal properties. These methods are productive in diverse pockets of chemical space, producing complex saturated pharmaceuticals bearing a variety of functional groups and three-dimensional architectures. The rhodium-catalyzed method tolerates traces of dimethyl sulfoxide (DMSO) or water, meaning that pharmaceutical compound collections, which are typically stored in wet DMSO, can finally be reformatted for use as substrates for chemical synthesis. This latter application is demonstrated through the late-stage saturation (LSS) of 768 complex and densely functionalized small-molecule drugs.


Assuntos
Ródio , Catálise , Ródio/química , Preparações Farmacêuticas/química , Preparações Farmacêuticas/síntese química , Hidrogenação , Estrutura Molecular
3.
Angew Chem Int Ed Engl ; 63(21): e202402819, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38480464

RESUMO

Dearomative partial reduction is an extraordinary approach for transforming benzenoid arenes and has been well-known for many decades, as exemplified by the dehydrogenation of Birch reduction and the hydroarylation of Crich addition. Despite its remarkable importance in synthesis, this field has experienced slow progress over the last half-century. However, a revival has been observed with the recent introduction of electrochemical and photochemical methods. In this Minireview, we summarize the recent advancements in dearomative partial reduction of benzenoid arenes, including dihydrogenation, hydroalkylation, arylation, alkenylation, amination, borylation and others. Further, the intriguing utilization of dearomative partial reduction in the synthesis of natural products is also emphasized. It is anticipated that this Minireview will stimulate further progress in arene dearomative transformations.

4.
Angew Chem Int Ed Engl ; 62(48): e202312203, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37803457

RESUMO

(Hetero)arene reduction is one of the key avenues for synthesizing related cyclic alkenes and alkanes. While catalytic hydrogenation and Birch reduction are the two broadly utilized approaches for (hetero)arene reduction across academia and industry over the last century, both methods have encountered significant chemoselectivity challenges. We hereby introduce a highly chemoselective quinoline and isoquinoline reduction protocol operating through selective energy transfer (EnT) catalysis, which enables subsequent hydrogen atom transfer (HAT). The design of this protocol bypasses the conventional metric of reduction reaction, that is, the reductive potential, and instead relies on the triplet energies of the chemical moieties and the kinetic barriers of energy and hydrogen atom transfer events. Many reducing labile functional groups, which were incompatible with previous (hetero)arene reduction reactions, are retained in this reaction. We anticipate that this protocol will trigger the further advancement of chemoselective arene reduction and enable the current arene-rich drug space to escape from flatland.

5.
Int J Mol Sci ; 22(14)2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34299293

RESUMO

Brassinosteroids (BRs) are growth-promoting phytohormones that can efficiently function by exogenous application at micromolar concentrations or by endogenous fine-tuning of BR-related gene expression, thus, precisely controlling BR signal strength is a key factor in exploring the agricultural potential of BRs. BRASSINOSTEROID INSENSITIVE1 (BRI1), a BR receptor, is the rate-limiting enzyme in BR signal transduction, and the phosphorylation of each phosphorylation site of SlBRI1 has a distinct effect on BR signal strength and botanic characteristics. We recently demonstrated that modifying the phosphorylation sites of tomato SlBRI1 could improve the agronomic traits of tomato to different extents; however, the associated agronomic potential of SlBRI1 phosphorylation sites in tomato has not been fully exploited. In this research, the biological functions of the phosphorylation site threonine-825 (Thr-825) of SlBRI1 in tomato were investigated. Phenotypic analysis showed that, compared with a tomato line harboring SlBRI1, transgenic tomato lines expressing SlBRI1 with a nonphosphorylated Thr-825 (T825A) exhibited a larger plant size due to a larger cell size and higher yield, including a greater plant height, thicker stems, longer internodal lengths, greater plant expansion, a heavier fruit weight, and larger fruits. Molecular analyses further indicated that the autophosphorylation level of SlBRI1, BR signaling, and gibberellic acid (GA) signaling were elevated when SlBRI1 was dephosphorylated at Thr-825. Taken together, the results demonstrated that dephosphorylation of Thr-825 can enhance the functions of SlBRI1 in BR signaling, which subsequently activates and cooperates with GA signaling to stimulate cell elongation and then leads to larger plants and higher yields per plant. These results also highlight the agricultural potential of SlBRI1 phosphorylation sites for breeding high-yielding tomato varieties through precise control of BR signaling.


Assuntos
Brassinosteroides/metabolismo , Proteínas Serina-Treonina Quinases/genética , Solanum lycopersicum/genética , Tamanho Celular , Frutas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Fosforilação , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/genética , Treonina/metabolismo
6.
Chemistry ; 25(48): 11223-11227, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31298766

RESUMO

Oxotryptamines were firstly used as flexible four-atom synthons in an NHC-catalyzed formal [4+3] annulation, providing a novel enantioselective method to access structurally diverse spiro-ϵ-lactam oxindoles with excellent enantioselectivities. This metal-free reaction features a broad substrate scope, excellent functional-group tolerance and proceeds under mild reaction conditions. Importantly, enantiopure privileged hexahydropyrroloindoles could be easily constructed by a one-pot process from the resulting spiro-ϵ-lactam oxindoles.

7.
J Org Chem ; 83(22): 14210-14217, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30351940

RESUMO

Direct and rapid construction of carbazoles has been successfully developed via carbene-catalyzed oxidative formal [4 + 2] annulation of enals with 2-methyl-3-oxoacetate indoles. This metal-free reaction features a broad substrate scope, features good functional-group tolerance, proceeds under mild conditions, and can be easily scaled up.

8.
Int J Syst Evol Microbiol ; 67(5): 1522-1528, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28005518

RESUMO

A Gram-staining-positive, non-spore-forming and non-motile strain, designated WYH11-7T, was isolated from a phosphate mine in Yunnan Province, PR China. The taxonomic position of WYH11-7T was investigated by polyphasic approaches. Phylogenetic analyses based on 16S rRNA gene sequences indicated that WYH11-7T represents a member of the genus Nocardioides. WYH11-7T was closely related to Nocardioidesjensenii DSM 20641T, Nocardioidesdubius DSM 19084T and Marmoricolaterrae DSM 27141T, and had pairwise 16S rRNA gene sequence similarities of 97.4, 97.2 and 97.0 %, respectively. DNA-DNA relatedness values between WYH11-7T and related type strains N. jensenii DSM 20641T and N. dubius DSM 19084T were found to be 17.6±4.9 and 14.6±3.1 %, respectively. The respiratory menaquinone of WYH11-7T was MK-8 (H4) while the major fatty acids were C18 : 1ω9c, C16 : 0, C17 : 0, C17 : 1ω8c, C18 : 1 10-methyl and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids. Whole-cell hydrolysates contained mannose, ribose, glucose and galactose along with ll-diaminopimelic acid as the diagnostic diamino acid in the peptidoglycan. The DNA G+C content was 71.2 mol%. Phenotypic, phylogenetic and chemotaxonomic data indicated that strain WYH11-7T represents a novel species of the genus Nocardioides, for which the name Nocardioidesphosphatisp. nov. is proposed. The type strain is WYH11-7T (=CGMCC 4.7371T=DSM 104026T).


Assuntos
Actinomycetales/classificação , Fosfatos , Filogenia , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Mineração , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Int J Syst Evol Microbiol ; 66(1): 456-461, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541594

RESUMO

A Gram-stain-negative, facultatively anaerobic, non-pigmented, non-sporulating, rod-shaped bacterial strain (WYH 22-41T) was isolated from a phosphate mine in Yunnan Province, China. The cells were motile with a single polar flagellum. The 16S rRNA gene of strain WYH 22-41T was phylogenetically related to the corresponding gene of Comamonas terrae DSM 27221T (98.4 % 16S rRNA gene sequence similarity), Comamonas odontotermitis LMG 23579T (97.6 %) and Comamonas aquatica LMG 2370T (97.4 %). DNA-DNA hybridizations of strain WYH 22-41T with these three strains showed relatedness values of 33.2 %, 20.5 % and 27.7 %, respectively. The DNA G+C content of strain WYH 22-41T was 62.4 mol%. The predominant respiratory quinone was ubiquinone-8. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The major fatty acids of strain WYH 22-41T were C16 : 0, C17 : 0 cyclo, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). On the basis of phenotypic properties, phylogenetic characteristics, DNA-DNA hybridization, as well as whole-cell fatty acid composition, strain WYH 22-41T represents a novel species of the genus Comamonas, for which the name Comamonas phosphati sp. nov. is proposed. The type strain is WYH 22-41T ( = CGMCC 1.12294T = DSM 26017T).


Assuntos
Comamonas/classificação , Mineração , Fosfatos , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Comamonas/genética , Comamonas/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
10.
Int J Syst Evol Microbiol ; 64(Pt 2): 559-564, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24225026

RESUMO

A Gram-stain-negative, rod-shaped, exopolysaccharide-producing, strictly aerobic bacterium with a single polar flagellum, designated strain HL22-2(T), was isolated from a phosphate mine situated in a suburb of Kunmming in Yunnan province in south-western China. The taxonomic status of this strain was evaluated by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HL22-2(T) was related to members of the genus Pseudomonas. 16S rRNA gene sequence similarities between strain HL22-2(T) and Pseudomonas xanthomarina KMM 1447(T), Pseudomonas alcaliphila AL15-21(T) and Pseudomonas stutzeri ATCC 17588(T) were 98.9, 98.10% and 98.06%, respectively. The major cellular fatty acids were C(18 : 1)ω7c, C(16 : 0) and summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c). The DNA G+C content was 60.3 mol%. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness values, strain HL22-2(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas kunmingensis sp. nov. is proposed. The type strain is HL22-2(T) ( = CGMCC 1.12273(T) = DSM 25974(T)).


Assuntos
Mineração , Filogenia , Pseudomonas/classificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfatos , Pseudomonas/genética , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
11.
Int J Syst Evol Microbiol ; 64(Pt 7): 2324-2329, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24737793

RESUMO

A yellow-pigmented, Gram-stain-negative, strictly aerobic, rod-shaped, round-ended bacterium, designated strain 18-11HK(T), was isolated from a phosphate mine situated in the suburb of Kunming in Yunnan province in south-western China. The taxonomic status of this strain was evaluated by using a polyphasic approach. On the basis of 16S rRNA gene sequence similarity, strain 18-11HK(T) was shown to belong to the genus Novosphingobium, showing the highest levels of sequence similarity with respect to 'Novosphingobium ginsenosidimutans' FW-6 (97.2%), Novosphingobium subterraneum DSM 12447(T) (96.7%), Novosphingobium aromaticivorans DSM 12444(T) (96.7%) and Novosphingobium tardaugens DSM 16702(T) (96.3%). Strain 18-11HK(T) had a genomic DNA G+C content of 65.3 mol% and Q-10 as the predominant respiratory quinone. DNA-DNA hybridizations of strain 18-11HK(T) with N. subterraneum DSM 12447(T), N. aromaticivorans DSM 12444(T) and N. tardaugens DSM 16702(T) showed low relatedness values of 29.6, 33.5 and 32.3%, respectively. The predominant fatty acids of strain 18-11HK(T) were summed feature 8 (C18 : 1ω7c and/or C18: 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0, and the major 2-hydroxy fatty acid was C14 : 0 2-OH. The polar lipid profile revealed the presence of sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and some unidentified lipids. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain 18-11HK(T) represents a novel species of the genus Novosphingobium, for which the name Novosphingobium kunmingense sp. nov. is proposed. The type strain is 18-11HK(T) ( = CGMCC 1.12274(T) = DSM 25975(T)).


Assuntos
Mineração , Fosfatos/química , Filogenia , Microbiologia do Solo , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Ubiquinona/química
12.
J Clin Med ; 13(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38398313

RESUMO

Objectives: The study aims to explore the ocular biometry of a myopic population in Northern China, focusing specifically on anterior and posterior segment lengths. Methods: This is a cross-sectional study. The medical records of 3458 myopic patients who underwent refractive surgery were evaluated. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT) and other biometric parameters were measured using the IOL Master 700. The study determined the anterior segment length (ASL = ACD + LT), the posterior segment length (PSL = AL - ASL) and the ratio of ASL to PSL (ASL/PSL). Results: This study included 3458 eyes from 3458 myopic patients (1171 men and 2287 women). The mean age was 27.38 ± 6.88, ranging from 16 to 48 years old. The mean ASL was 7.35 ± 0.27 mm, and the mean PSL was 18.39 ± 1.18 mm. The ASL and PSL trends demonstrate an age-related increase for both genders, with notable gender-specific variations. Across most age groups, males typically exhibited higher ASLs and PSLs than females, with the exception of the 35-40 and 40-45 age groups. The ASL and PSL consistently increased with a rising AL. The AL strongly correlates with the PSL and negatively correlates with the ASL/PSL ratio. The ACD and LT moderately correlate with the ASL, but an increased LT does not imply a longer posterior segment. The CCT and SE show little correlation with axial eye parameters. Conclusions: Among Chinese myopic patients, a longer ASL and PSL were correlated with older age and the male gender. The AL strongly correlates positively with the PSL and negatively correlates with the ASL/PSL ratio. An elongation of the posterior segment may primarily account for an eyeball's lengthening.

13.
Environ Sci Pollut Res Int ; 30(29): 74327-74339, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37204584

RESUMO

Under the background of peaking carbon neutralization, it is a significant and fresh proposition to investigate the economic benefits of carbon disclosure (CD) in the Chinese market. By taking all listed enterprises as a sample (2009-2020), this paper firstly empirically analyzes the impact of enterprise CD on stock price synchronization and the indispensable role played by analysts in between. The results indicate that (1) enterprise CD is conducive to reduce stock price synchronization, confirming the accuracy of government mandatory CD system and the effectiveness of voluntary enterprise CD project. (2) Analysts play the role of "information scouts" and have a mediating effect between enterprise CD and stock price synchronization. (3) Analysts play the role of "analysis commentators," and analyst rating has a moderating effect between enterprise CD and stock price synchronization. (4) In further analysis, analysts will mobilize investors' positive investment sentiment, but only when the analyst rating upgrades or remains unchanged.


Assuntos
Carbono , Revelação , Governo , Investimentos em Saúde , China , Indústrias/economia , Desenvolvimento Sustentável
14.
Braz J Microbiol ; 54(1): 361-370, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36574205

RESUMO

Peanut stem rot caused by Sclerotium rolfsii Sacc. is the most common disease of peanut worldwide and has become increasingly serious in recent years. This study is aimed at obtaining peanut endophytic bacteria with high antagonistic/protective effects against peanut stem rot. In total, 45 bacterial strains were isolated from healthy peanut plants from a severely impacted area. Of these, 6 exhibited antagonistic activity against S. rolfsii, including F-1 and R-11 with the most robust activity with an inhibition zone width of 20.25 and 15.49 mm, respectively. These two were identified as Bacillus sp. and Burkholderia sp., respectively, based on morphological, physiological, and biochemical characteristics and 16S rDNA sequencing. To the best of our knowledge, this is the first study to report the Burkholderia sp. antagonistic effect on S. rolfsii as a biological control agent for peanut stem rot. Their culture filtrates potently inhibited the hyphal growth, sclerotial formation, and germination of S. rolfsii. Also, the strain-produced volatile compounds inhibited the fungal growth. Pot experiments showed that F-1 and R-11 significantly reduced the peanut stem rot disease with the efficacy of 77.13 and 64.78%, respectively, which was significantly higher compared with carbendazim medicament (35.22%; P < 0.05). Meanwhile, F-1 and R-11 improved the activity of plant defense enzymes such as phenylalaninase (PAL), polyphenol oxidase (PPO), and peroxidase (POD) enhancing the systemic resistance of the peanut plants. This study demonstrated that Bacillus sp. F-1 and Burkholderia sp. R-11, with a strong antagonistic effect on S. rolfsii, can be potential biocontrol agents for peanut stem rot.


Assuntos
Ascomicetos , Bacillus , Basidiomycota , Arachis/microbiologia , Ascomicetos/fisiologia , Bacillus/genética
15.
Med Eng Phys ; 114: 103974, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37030897

RESUMO

The orthodontic treatment can be guided by the finite element (FE) simulation of periodontal ligament (PDL) mechanical properties, and the biomimetic degree of FE simulation can be primarily affected by the material properties of the PDL. According to the principle of parameter inverse, a method: response surface (RS) method and FE inverse method were proposed to identify the material parameters of PDL. The Prony series viscoelastic FE model was established based on the relaxation experiment. With root mean square error of simulation results and experimental results as the objective function, the optimal parameter combination was obtained by RS method, and the FE simulation result were compared with the experimental result. The result showed that the optimal parameters of the PDL were elastic modulus: 3.791 MPa, Poisson's ratio: 0.42, temperature: 29.294°C separately, and the simulation result of optimal combination maintained consistency with experiment with the correlation coefficient of 0.97258, indicating that the method proposed in this paper could well identify of PDL material parameters. The parameter identification method used in this paper can significantly improve the calculation efficiency, and reduce the parameter identification error compared with the simple FE inverse method, which has scientific significance and theoretical value.


Assuntos
Modelos Biológicos , Ligamento Periodontal , Ligamento Periodontal/fisiologia , Estresse Mecânico , Fenômenos Biomecânicos , Análise de Elementos Finitos , Simulação por Computador
16.
Front Bioeng Biotechnol ; 10: 974646, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051593

RESUMO

RNAi technology, known as a revolutionary technology in the history of pesticides, has been identified as a very promising novel approach for crop protection, which is of great significance for achieving the sustainable agricultural development of the United Nations Food and Agriculture Organization. Although many studies have shown that RNA biopesticides have strong application prospects, its stability seriously restricts the commercial use. As the core component of RNAi, double-stranded RNA (dsRNA) is unstable in its natural form. Therefore, how to ensure the stability of dsRNA is one of the most significant challenges in realizing the commercial use of RNA biopesticides. Nanomaterials such as cationic polymers and lipofectamine can improve the stability of dsRNA in the environment, which has been proved. This paper reviews the recent research progress of nanomaterials that can be used to improve the environmental stability of dsRNA, and discusses the advantages and limitations of different nanomaterials combined with dsRNA, which provides reference for the selection of dsRNA nanoformulations.

17.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112188, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34742021

RESUMO

Some microbial strains are ideal producers of extracellular enzymes that can be used in various industries. However, in many fields, especially in the pharmaceutical field, these enzymes need to be recovered and purified through multistep processes and tedious procedures before they can be used. The recovery process is difficult and increases the cost of enzyme production. Therefore, reducing purification steps will greatly benefit the utilization of microbial enzymes. The 35 M strain of Bacillus amyloliquefaciens, which has high extracellular protease production, was isolated from a phosphate mine. When cultured in a medium with soybean meal as the main component, the maximum activity of extracellular protease reached 16,992 U/mL. SDS-PAGE showed that there were two main proteins in the fermentation supernatant, with a paucity of other defined protein bands. Mass spectrometry and zymogram analysis showed that the two main bands were two proteases, corresponding to alkaline protease (AprM) and neutral protease (NprM), respectively. Gene cloning, sequencing, and further comparisons were used to confirm AprM and NprM correspond to these proteases from B. amyloliquefaciens. Notably, SDS-PAGE and zymogram analysis showed that NprM had obviously higher catalytic efficiency toward casein than did AprM. Strain 35 M is a promising protease producer with great potential for applications in industrial protease production. Additionally, this study demonstrates strain 35 M may be particularly well suited to use in degrading anti-nutritional factors in soybean meal, so as to improve the nutritional value of soybean meal.


Assuntos
Bacillus amyloliquefaciens , Bacillus amyloliquefaciens/genética , Bacillus amyloliquefaciens/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Fermentação , Peptídeo Hidrolases/metabolismo , Glycine max
18.
Microbiol Spectr ; 10(5): e0241122, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36125274

RESUMO

Ethylene regulates mycelial growth, primordium formation, and postharvest mushroom maturation and senescence in the white button mushroom, Agaricus bisporus. However, it remains unknown how ethylene is detected by the mushroom. In this study, we found that two hybrid histidine kinases in the mushroom, designated AbETR1 and AbETR2, showed domain structures similar to those of plant ethylene receptors. The transmembrane helices of AbETR1 and AbETR2 were expressed in yeast cells and showed ethylene-binding activities. Mushroom strains with downregulated expressions of AbETR1 and AbETR2 showed reduced sensitivity to the ethylene inhibition of mycelial growth, ethylene regulation of their own synthesis, postharvest mushroom maturation, and senescence and expression of maturation- and senescence-related genes. Therefore, AbETR1 and AbETR2 are expected to be biologically functional ethylene receptors and exhibit a different mode of action from that of the receptors of plants. Here, we fill gaps in the knowledge pertaining to higher fungus ethylene receptors, discover a novel mode of action of ethylene receptors, confirm ethylene as a novel fungal hormone, and provide a facilitated approach for preventing the maturation and senescence of postharvest button mushrooms. IMPORTANCE Ethylene regulates diverse physiological activities in bacteria, cyanobacteria, fungi, and plants, but how to perceive ethylene by fungi only remains unknown. In this study, we identify two biologically functional ethylene receptors in the basidiomycete fungus Agaricus bisporus, which fills the gaps of deficient fungal ethylene receptors. Furthermore, we found that decreased expression of the ethylene receptors facilitates preventing the maturation and senescence of postharvest button mushrooms, indicating that the two fungal ethylene receptors positively regulate the ethylene response, in contrast to that in plants.


Assuntos
Etilenos , Histidina , Histidina Quinase/genética , Etilenos/metabolismo , Hormônios
19.
Org Lett ; 21(4): 926-930, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30714381

RESUMO

A novel strategy for the construction of 2,2-diacyl spirocyclohexanones 3 has been demonstrated on the basis of an NHC-catalyzed [3C + 3C] annulation of potassium 2-oxo-3-enoates with 2-ethylidene 1,3-indandiones. Furthermore, enantioenriched 3 was obtained in good to excellent yields with good enantioselectivities when chiral N-heterocyclic carbene (NHC) was employed. Notably, ring opening of the resulting 2,2-diacyl spirocyclohexanones 3 with hydrazine led to the formation of phthalazinones in good to excellent yields.

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