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1.
Plant Physiol ; 195(2): 1347-1364, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38488068

RESUMO

Potato (Solanum tuberosum L.) is cultivated worldwide for its underground tubers, which provide an important part of human nutrition and serve as a model system for belowground storage organ formation. Similar to flowering, stolon-expressed FLOWERING LOCUS T-like (FT-like) protein SELF-PRUNING 6A (StSP6A) plays an instrumental role in tuberization by binding to the bZIP transcription factors StABI5-like 1 (StABL1) and StFD-like 1 (StFDL1), causing transcriptional reprogramming at the stolon subapical apices. However, the molecular mechanism regulating the widely conserved FT-bZIP interactions remains largely unexplored. Here, we identified a TCP transcription factor StAST1 (StABL1 and StSP6A-associated TCP protein 1) binding to both StSP6A and StABL1. StAST1 is specifically expressed in the vascular tissue of leaves and developing stolons. Silencing of StAST1 leads to accelerated tuberization and a shortened life cycle. Molecular dissection reveals that the interaction of StAST1 with StSP6A and StABL1 attenuates the formation of the alternative tuberigen activation complex (aTAC). We also observed StAST1 directly activates the expression of potato GA 20-oxidase gene (StGA20ox1) to regulate GA responses. These results demonstrate StAST1 functions as a tuberization repressor by regulating plant hormone levels; our findings also suggest a mechanism by which the widely conserved FT-FD genetic module is fine-tuned.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Tubérculos , Solanum tuberosum , Fatores de Transcrição , Solanum tuberosum/genética , Solanum tuberosum/metabolismo , Solanum tuberosum/fisiologia , Solanum tuberosum/crescimento & desenvolvimento , Tubérculos/genética , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Tubérculos/fisiologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
2.
Plant J ; 113(2): 402-415, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36562774

RESUMO

Photoperiod plays a critical role in controlling the formation of sexual or vegetative reproductive organs in potato. Although StPHYF-silenced plants overcome day-length limitations to tuberize through a systemic effect on tuberigen StSP6A expression in the stolon, the comprehensive regulatory network of StPHYF remains obscure. Therefore, the present study investigated the transcriptomes of StPHYF-silenced plants and observed that, in addition to known components of the photoperiodic tuberization pathway, florigen StSP3D and other flowering-related genes were activated in StPHYF-silenced plants, exhibiting an early flowering response. Additionally, grafting experiments uncovered the long-distance effect of StPHYF silencing on gene expression in the stolon, including the circadian clock components, flowering-associated MADSs, and tuberization-related regulatory genes. Similar to the AtFT-AtAP1 regulatory module in Arabidopsis, the present study established that the AP1-like StMADS1 functions downstream of the tuberigen activation complex (TAC) and that suppressing StMADS1 inhibits tuberization in vitro and delays tuberization in vivo. Moreover, the expression of StSP6A was downregulated in StMADS1-silenced plants, implying the expression of StSP6A may be feedback-regulated by StMADS1. Overall, these results reveal that the regulatory network of StPHYF controls flowering and tuberization and targets the crucial tuberization factor StMADS1 through TAC, thereby providing a better understanding of StPHYF-mediated day-length perception during potato reproduction.


Assuntos
Arabidopsis , Fitocromo , Solanum tuberosum , Fitocromo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Solanum tuberosum/metabolismo , Transcriptoma , Tubérculos/metabolismo , Folhas de Planta/metabolismo , Fotoperíodo , Arabidopsis/genética , Reprodução , Regulação da Expressão Gênica de Plantas/genética
3.
Opt Express ; 32(5): 7207-7219, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439408

RESUMO

Recent advances in ptychography have extended to anisotropic specimens, but vectorial reconstruction of probes owing to polarization aliasing remains a challenge. A polarization-sensitive ptychography that enables full optical property measurement of vector light is proposed. An optimized reconstruction strategy, first calibrating the propagation direction and then performing faithful retrieval, is established. This method avoids multiple image acquisitions with various polarizer configurations and significantly improves the measurement accuracy by correlating the intensity and position of different polarization components. The capability of the proposed method to quantify anisotropic parameters of optical materials and polarization properties of vector probe is demonstrated by experiment.

4.
Biomacromolecules ; 25(1): 238-247, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38116793

RESUMO

Chitinase plays a vital role in the efficient biotransformation of the chitin substrate. This study aimed to modify and elucidate the contribution of the relatively conserved residues in the active site architecture of a thermophilic chitinase SsChi18A from Streptomyces sp. F-3 in processive catalysis. The enzymatic activity on colloidal chitin increased to 151%, 135%, and 129% in variants Y286W, E287A, and K186A compared with the wild type (WT). Also, the apparent processive parameter G2/G1 was lower in the variants compared to the WT, indicating the essential role of Tyr-286, Glu-287, and Lys-186 in processive catalysis. Additionally, the enzymatic activity on the crystalline chitin of F48W and double mutants F48W/Y209F and F48W/Y286W increased by 35%, 16%, and 36% compared with that for WT. Molecular dynamics simulations revealed that the driving force of processive catalysis might be related to the changes in interaction energy. This study provided a rational design strategy targeting relatively conserved residues to enhance the catalytic activity of GH18 processive chitinases.


Assuntos
Quitinases , Domínio Catalítico , Quitinases/genética , Quitinases/química , Quitinases/metabolismo , Quitina/química , Simulação de Dinâmica Molecular
5.
EMBO Rep ; 23(9): e54611, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35833522

RESUMO

Inflammasomes are cytosolic multiprotein complexes that initiate host defense against bacterial pathogens. The nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family caspase-associated recruitment domain-containing protein 4 (NLRC4) inflammasomes plays a critical role in the inflammatory response against intracellular bacterial infection. The NLR family apoptosis inhibitory proteins (NAIPs) detect Flagellin or type III secretion system (T3SS) microbial components to activate NLRC4 inflammasome. However, the underlying mechanism of NLRC4 inflammasome activation is not completely understood. Here, we show that the vitamin D receptor (VDR) is an essential immunological regulator of the NLRC4 inflammasome. Conditional VDR knockout mice (VDRflox/flox lyz2-Cre) exhibited impaired clearance of pathogens after acute Salmonella Typhimurium infection leading to poor survival. In macrophages, VDR deficiency reduced caspase-1 activation and IL-1ß secretion upon S. Typhimurium infection. For NAIPs act as upstream sensors for NLRC4 inflammasome assembly, the further study demonstrated that VDR promoted the NAIP-NLRC4 association and triggered NAIP-NLRC4 inflammasome activation, not NLRP3 activation. Moreover, Lys123 residue of VDR is identified as the critical amino acid for VDR-NLRC4 interaction, and the mutant VDR (K123A) effectively attenuates the NLRC4 inflammasome activation. Together, our findings suggest that VDR is a critical regulator of NAIPs-NLRC4 inflammasome activation, mediating innate immunity against bacterial infection.


Assuntos
Proteínas Reguladoras de Apoptose , Infecções Bacterianas , Proteínas de Ligação ao Cálcio , Inflamassomos , Receptores de Calcitriol , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Caspases/metabolismo , Inflamassomos/metabolismo , Camundongos , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo
6.
Mar Drugs ; 22(5)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38786621

RESUMO

Alginate oligosaccharides (AOS), products of alginate degradation by endotype alginate lyases, possess favorable biological activities and have broad applications. Although many have been reported, alginate lyases with homogeneous AOS products and secretory production by an engineered host are scarce. Herein, the alginate lyase AlyC7 from Vibrio sp. C42 was characterized as a trisaccharide-producing lyase exhibiting high activity and broad substrate specificity. With PelB as the signal peptide and 500 mM glycine as the additive, the extracellular production of AlyC7 in Escherichia coli reached 1122.8 U/mL after 27 h cultivation in Luria-Bertani medium. The yield of trisaccharides from sodium alginate degradation by the produced AlyC7 reached 758.6 mg/g, with a purity of 85.1%. The prepared AOS at 20 µg/mL increased the root length of lettuce, tomato, wheat, and maize by 27.5%, 25.7%, 9.7%, and 11.1%, respectively. This study establishes a robust foundation for the industrial and agricultural applications of AlyC7.


Assuntos
Escherichia coli , Polissacarídeo-Liases , Trissacarídeos , Vibrio , Polissacarídeo-Liases/metabolismo , Trissacarídeos/biossíntese , Vibrio/enzimologia , Especificidade por Substrato , Alginatos , Zea mays , Oligossacarídeos
7.
Biochem Genet ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300006

RESUMO

Severe Corona Virus Disease 2019 (COVID-19) patients may develop acute respiratory distress syndrome (ARDS). Modified Ginseng Baidu Powder (referred to as Baidu Powder) was used for respiratory system diseases caused by colds. To study the effect of Baidu Powder on protecting ARDS mice model and its underlying active ingredients and targets intervening in COVID-19. The optimal LPS concentration was selected for the induction of mouse ARDS model, and the protective effect of Baidu Powder prophylactic administration on LPS-induced ARDS mouse models was explored by mouse survival time analysis, lung wet/dry weight (W/D) ratio, pathological staining, and inflammatory factor detection. On the basis of pharmacodynamics, the network pharmacological analysis was used for target prediction for future mechanism study. 5 mg/kg LPS was selected for the construction of a mouse ARDS model, based on a mortality rate of 87% and the lung W/D ratio of 5.29 ± 0.23. Prophylactic administration of Baidu Powder at 125 g/L significantly reduced death, lung damage, inflammatory cell infiltration, and cytokine production (TNF-α, IL-6, and IL-10) caused by LPS-induced ARDS. The results of network pharmacological analysis showed that 42 target genes of Baidu Powder intervening in COVID-19 were involved in 30 biological processes related to COVID-19 and inflammation, and 11 signaling pathways related to lung diseases or inflammation. 5 mg/kg LPS can successfully establish a mice ARDS disease model; 125 g/L Baidu Powder prophylactic administration does not have toxicity and has a certain effect on protecting ARDS mouse models induced by LPS. Baidu Powder may intervene COVID-19-induced ARDS through multiple targets.

8.
Mikrochim Acta ; 191(5): 286, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652378

RESUMO

A perennial challenge in harnessing the rich biological activity of medicinal and edible plants is the accurate identification and sensitive detection of their active compounds. In this study, an innovative, ultra-sensitive detection platform for plant chemical profiling is created using surface-enhanced Raman spectroscopy (SERS) technology. The platform uses silver nanoparticles as the enhancing substrate, excess sodium borohydride prevents substrate oxidation, and methanol enables the tested molecules to be better adsorbed onto the silver nanoparticles. Subsequently, nanoparticle aggregation to form stable "hot spots" is induced by Ca2+, and the Raman signal of the target molecule is strongly enhanced. At the same time, deuterated methanol was used as the internal standard for quantitative determination. The method has excellent reproducibility, RSD ≤ 1.79%, and the enhancement factor of this method for the detection of active ingredients in the medicinal plant Coptis chinensis was 1.24 × 109, with detection limits as low as 3 fM. The platform successfully compared the alkaloid distribution in different parts of Coptis chinensis: root > leaf > stem, and the difference in content between different batches of Coptis chinensis decoction was successfully evaluated. The analytical technology adopted by the platform can speed up the determination of Coptis chinensis and reduce the cost of analysis, not only making better use of these valuable resources but also promoting development and innovation in the food and pharmaceutical industries. This study provides a new method for the development, evaluation, and comprehensive utilization of both medicinal and edible plants. It is expected that this method will be extended to the modern rapid detection of other medicinal and edible plants and will provide technical support for the vigorous development of the medicinal and edible plants industry.


Assuntos
Nanopartículas Metálicas , Plantas Comestíveis , Plantas Medicinais , Prata , Análise Espectral Raman , Análise Espectral Raman/métodos , Nanopartículas Metálicas/química , Plantas Medicinais/química , Prata/química , Plantas Comestíveis/química , Limite de Detecção , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Reprodutibilidade dos Testes , Alcaloides/análise
9.
Molecules ; 29(16)2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39203048

RESUMO

To synthesize an effective and versatile nano-platform serving as a promising carrier for controlled drug delivery, visible-light-induced diselenide-crosslinked polyurethane micelles were designed and prepared for ROS-triggered on-demand doxorubicin (DOX) release. A rationally designed amphiphilic block copolymer, poly(ethylene glycol)-b-poly(diselenolane diol-co-isophorone diisocyanate)-b-poly(ethylene glycol) (PEG-b-PUSe-b-PEG), which incorporates dangling diselenolane groups within the hydrophobic PU segments, was initially synthesized through the polycondensation reaction. In aqueous media, this type of amphiphilic block copolymer can self-assemble into micellar aggregates and encapsulate DOX within the micellar core, forming DOX-loaded micelles that are subsequently in situ core-crosslinked by diselenides via a visible-light-triggered metathesis reaction of Se-Se bonds. Compared with the non-crosslinked micelles (NCLMs), the as-prepared diselenide-crosslinked micelles (CLMs) exhibited a smaller particle size and improved colloidal stability. In vitro release studies have demonstrated suppressed drug release behavior for CLMs in physiological conditions, as compared to the NCLMs, whereas a burst release of DOX occurred upon exposure to an oxidation environment. Moreover, MTT assay results have revealed that the crosslinked polyurethane micelles displayed no significant cytotoxicity towards HeLa cells. Cellular uptake analyses have suggested the effective internalization of DOX-loaded crosslinked micelles and DOX release within cancer cells. These findings suggest that this kind of ROS-triggered reversibly crosslinked polyurethane micelles hold significant potential as a ROS-responsive drug delivery system.


Assuntos
Doxorrubicina , Luz , Micelas , Polímeros , Espécies Reativas de Oxigênio , Doxorrubicina/química , Doxorrubicina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Humanos , Polímeros/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Células HeLa , Polietilenoglicóis/química , Sobrevivência Celular/efeitos dos fármacos , Tamanho da Partícula
10.
Plant J ; 109(4): 952-964, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34837279

RESUMO

Phytohormones and their interactions play critical roles in Solanum tuberosum (potato) tuberization. The stimulatory role of jasmonic acid (JA) in tuber development is well established because of its significant promotion of tuber initiation and tuber bulking. However, the dynamics and potential function of JA signalling in potato tuberization remain largely unknown. The present study investigated the role of the JAZ1 subtype, a suppressor of JA signalling, in potato tuberization. Using 35S:StJAZ1-like-GUS as a reporter, we showed that JA signalling was attenuated from the bud end to the stem end shortly after tuber initiation. Overexpression of StJAZ1-like suppressed tuber initiation by restricting the competence for tuber formation in stolon tips, as demonstrated by grafting an untransformed potato cultivar to the stock of StJAZ1-like-overexpressing transgenic potato plants (StJAZ1-like ox). In addition, transcriptional profiling analysis revealed that StJAZ1-like modulates the expression of genes associated with transcriptional regulators, cell cycle, cytoskeleton and phytohormones. Furthermore, we showed that StJAZ1-like is destabilised upon treatment with abcisic acid (ABA), and the attenuated tuberization phenotype in StJAZ1-like ox plants can be partially rescued by ABA treatment. Altogether, these results revealed that StJAZ1-like-mediated JA signalling plays an essential role in potato tuberization.


Assuntos
Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Tubérculos/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Solanum tuberosum/metabolismo , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas , Plantas Geneticamente Modificadas/genética , Proteínas Repressoras/genética , Solanum tuberosum/genética , Fatores de Transcrição/metabolismo , Transcriptoma
11.
Plant Physiol ; 189(3): 1677-1693, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35258599

RESUMO

Potato (Solanum tuberosum L.) maturity involves several important traits, including the onset of tuberization, flowering, leaf senescence, and the length of the plant life cycle. The timing of flowering and tuberization in potato is mediated by seasonal fluctuations in photoperiod and is thought to be separately controlled by the FLOWERING LOCUS T-like (FT-like) genes SELF-PRUNING 3D (StSP3D) and SELF-PRUNING 6A (StSP6A). However, the biological relationship between these morphological transitions that occur almost synchronously remains unknown. Here, we show that StABI5-like 1 (StABL1), a transcription factor central to abscisic acid (ABA) signaling, is a binding partner of StSP3D and StSP6A, forming an alternative florigen activation complex and alternative tuberigen activation complex in a 14-3-3-dependent manner. Overexpression of StABL1 results in the early initiation of flowering and tuberization as well as a short life cycle. Using genome-wide chromatin immunoprecipitation sequencing and RNA-sequencing, we demonstrate that AGAMOUS-like and GA 2-oxidase 1 genes are regulated by StABL1. Phytohormone profiling indicates an altered gibberellic acid (GA) metabolism and that StABL1-overexpressing plants are insensitive to the inhibitory effect of GA with respect to tuberization. Collectively, our results suggest that StABL1 functions with FT-like genes to promote flowering and tuberization and consequently life cycle length in potato, providing insight into the pleiotropic functioning of the FT gene.


Assuntos
Solanum tuberosum , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ligação Proteica , Solanum tuberosum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Microb Cell Fact ; 22(1): 179, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689719

RESUMO

BACKGROUND: Alginate oligosaccharides (AOs) are the degradation products of alginate, a natural polysaccharide abundant in brown algae. AOs generated by enzymatic hydrolysis have diverse bioactivities and show broad application potentials. AOs production via enzymolysis is now generally with sodium alginate as the raw material, which is chemically extracted from brown algae. In contrast, AOs production by direct degradation of brown algae is more advantageous on account of its cost reduction and is more eco-friendly. However, there have been only a few attempts reported in AOs production from direct degradation of brown algae. RESULTS: In this study, an efficient Laminaria japonica-decomposing strain Pseudoalteromonas agarivorans A3 was screened. Based on the secretome and mass spectrum analyses, strain A3 showed the potential as a cell factory for AOs production by secreting alginate lyases to directly degrade L. japonica. By using the L. japonica roots, which are normally discarded in the food industry, as the raw material for both fermentation and enzymatic hydrolysis, AOs were produced by the fermentation broth supernatant of strain A3 after optimization of the alginate lyase production and hydrolysis parameters. The generated AOs mainly ranged from dimers to tetramers, among which trimers and tetramers were predominant. The degradation efficiency of the roots reached 54.58%, the AOs production was 33.11%, and the AOs purity was 85.03%. CONCLUSION: An efficient, cost-effective and green process for AOs production directly from the underutilized L. japonica roots by using strain A3 was set up, which differed from the reported processes in terms of the substrate and strain used for fermentation and the AOs composition. This study provides a promising platform for scalable production of AOs, which may have application potentials in industry and agriculture.


Assuntos
Alginatos , Laminaria , Análise Custo-Benefício , Oligossacarídeos
13.
Molecules ; 28(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38138516

RESUMO

Terpyridine (TPY) platinum(II) chloride with a triphenylamine (TPA) group was successfully synthesized. The strong intramolecular Donor(TPA)-Acceptor(TPY) interaction induced the low-energy absorption band, mixing the spin-allowed singlet dπ(Pt)→π*(TPY) metal-to-ligand charge transfer (MLCT) with the chloride ligand-to-metal charge transfer (LMCT) and chloride ligand-to-ligand (TPY) charge transfer (LLCT) transitions, to bathochromically shift to λmax = 449 nm with significant enhancement and broadening effects. Using the cyclic voltammetry method, its oxidative electropolymerization (EP) films on working Pt disk and ITO electrodes were produced with tunable thickness and diffusion controlled redox behavior, which were characterized by the SEM, EDS, FT-IR, and AC impedance methods. Upon applying +1.4 V voltage, the sandwich-type electrochromic device (ECD) with ca. 290 nm thickness of the EP film exhibits a distinct color transformation from red (CIE coordinates: L = 50.75, a = 18.58, b = 5.69) to dark blue (CIE coordinates: L = 45.65, a = -1.35, b = -12.49). Good electrochromic (EC) parameters, such as a large optical contrast (ΔT%) of 78%, quick coloration and bleaching response times of 2.9 s and 1.1 s, high coloration and bleaching efficiencies of 278.0 and 390.5 C-1·cm2, and good cycling stability (maintains 70% of the initial ΔT% value after 3200 voltage switching cycles), were obtained.

14.
Pharmacol Res ; 178: 106155, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35248699

RESUMO

The XELOX chemotherapy protocol that includes capecitabine and oxaliplatin is the routine treatment for colorectal cancer (CRC), but it can cause chemotherapy-related adverse events such as thrombocytopenia (TCP). To identify predictive biomarkers and clarify the mechanism of TCP susceptibility, we conducted integrative analysis using normal colorectal tissue (CRT), plasma, and urine samples collected before CRC patients received adjuvant XELOX chemotherapy. RNA-sequencing and DNA methylation arrays were performed on CRT samples, while liquid chromatography-mass spectrometry was performed on CRT, plasma, and urine samples. Differentially expressed features (DEFs) from each uni-omics analysis were then subjected to integrative analysis using Multi-Omics Factor Analysis (MOFA). Choline-deficiency in plasma and CRT was found as the most critical TCP-related feature. Based on bioinformatic analysis and literature research, we further concluded that choline-deficiency was the possible reason for most of the other TCP-related multi-omics DEFs, including metabolites representing reduced sphingolipid de novo synthesis and elevated solute carrier-mediated transmembrane transportation in CRT and plasma, DNA hypermethylation and elevated expression of genes involved in neuronal system genes. In terms of thrombocytopoiesis, these TCP-related DEFs may cause atypical maintenance and differentiation of megakaryocyte, resulting a suppressed ability of thrombocytopoiesis, making patients more susceptible to chemotherapy-induced TCP. At last, prediction models were developed and validated with reasonably good discrimination. The area under curves (AUCs) of training sets were all > 0.9, while validation sets had AUCs between 0.778 and 0.926. In conclusion, our results produced reliable marker systems for predicting TCP and promising target for developing precision treatment to prevent TCP.


Assuntos
Antineoplásicos , Deficiência de Colina , Neoplasias Colorretais , Leucopenia , Trombocitopenia , Antineoplásicos/efeitos adversos , Colina , Deficiência de Colina/induzido quimicamente , Deficiência de Colina/tratamento farmacológico , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Fluoruracila/uso terapêutico , Humanos , Leucopenia/induzido quimicamente , Trombocitopenia/induzido quimicamente
15.
Appl Opt ; 61(24): 7231-7236, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256344

RESUMO

The clamping stress of large-aperture optical elements has a significant influence on the optical quality of the system. In this study, a comprehensive measurement system combined with ptychographical iterative engine (PIE) wavefront sensors and polarization components is developed to determine the stress distribution of the optical elements and its effect on the transmitted and reflected wavefronts. This system avoids the use of multiple measuring instruments and has low cost and strong anti-interference ability. The experimental results demonstrate that the stress distributions measured at different resolutions are consistent with the finite element analysis, and the wavefront measurement accuracy is 0.1λ. This test configuration is very flexible and provides a useful means for online installation and quality control of large-aperture optical systems.

16.
Biotechnol Lett ; 44(3): 429-438, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35199255

RESUMO

OBJECTIVES: To develop a method for in vitro assembly of recombinant proteins expressed in E. coli into chimeric virus-like particles (cVLPs). RESULTS: A fusion protein (Bepi-Cap-A) between capsid protein (Cap) of PCV2b and B cell epitope (Bepi) of IBDV was expressed in E. Coli, and purified. For assembling them into cVLPs (Bepi-Cap-VLP), the Bepi-Cap-A was suspended in buffer C [0.03% ("%" stands for "v/v" unless otherwise indicated) polyethylene glycol, 0.4 M Tris, 10 mM ß-mercaptoethanol, 5% glycerol, 0.02% (w/v) gellan gum, 0.1 M glycine, 0.03% Tween 80, 500 mM NaCl], and incubated. After centrifugation, the pellet was resuspended in buffer D [50 mM Na2HPO4, 50 mM NaH2PO4, 0.01% (w/v) gellan gum, 0.05 mM EDTA, 500 mM NaCl, 0.03% Tween 80, pH 6.5], and then dialyzed against dialysis buffer (50 mM Na2HPO4, 50 mM NaH2PO4, 500 mM NaCl, 0.03% Tween 80, pH 6.5). The procedure resulted in typical and immunogenic Bepi-Cap-VLP. CONCLUSIONS: The data provide a method which is feasible for in vitro assembly of recombinant proteins into chimeric virus-like particles.


Assuntos
Circovirus , Vírus da Doença Infecciosa da Bursa , Animais , Anticorpos Antivirais/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Circovirus/genética , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/metabolismo , Polissorbatos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Cloreto de Sódio/metabolismo , Suínos
17.
Mar Drugs ; 20(12)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36547893

RESUMO

Alginate is abundant in the cell walls of brown algae. Alginate lyases can degrade alginate, and thus play an important role in the marine carbon cycle and industrial production. Currently, most reported alginate lyases contain only one functional alginate lyase domain. AlyC8 is a putative alginate lyase with two alginate lyase domains (CD1 and CD2) from the marine alginate-degrading strain Vibrio sp. C42. To characterize AlyC8 and its two catalytic domains, AlyC8 and its two catalytic domain-deleted mutants, AlyC8-CD1 and AlyC8-CD2, were expressed in Escherichia coli. All three proteins have noticeable activity toward sodium alginate and exhibit optimal activities at pH 8.0-9.0 and at 30-40 °C, demonstrating that both CD1 and CD2 are functional. However, CD1 and CD2 showed opposite substrate specificity. The differences in substrate specificity and degradation products of alginate between the mutants and AlyC8 demonstrate that CD1 and CD2 can act synergistically to enable AlyC8 to degrade various alginate substrates into smaller oligomeric products. Moreover, kinetic analysis indicated that AlyC8-CD1 plays a major role in the degradation of alginate by AlyC8. These results demonstrate that AlyC8 is a novel alginate lyase with two functional catalytic domains that are synergistic in alginate degradation, which is helpful for a better understanding of alginate lyases and alginate degradation.


Assuntos
Proteínas de Bactérias , Polissacarídeo-Liases , Vibrio , Alginatos/química , Concentração de Íons de Hidrogênio , Cinética , Polissacarídeo-Liases/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/isolamento & purificação , Especificidade por Substrato , Vibrio/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Mutação , Domínio Catalítico
18.
Mar Drugs ; 20(3)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35323458

RESUMO

Alginate oligosaccharides (AOS) have many biological activities and significant applications in prebiotics, nutritional supplements, and plant growth development. Alginate lyases have unique advantages in the preparation of AOS. However, only a limited number of alginate lyases have been so far reported to have potentials in the preparation of AOS with specific degrees of polymerization. Here, an alginate-degrading strain Pseudoalteromonasarctica M9 was isolated from Sargassum, and five alginate lyases were predicted in its genome. These putative alginate lyases were expressed and their degradation products towards sodium alginate were analyzed. Among them, AlyM2 mainly generated trisaccharides, which accounted for 79.9% in the products. AlyM2 is a PL6 lyase with low sequence identity (≤28.3%) to the characterized alginate lyases and may adopt a distinct catalytic mechanism from the other PL6 alginate lyases based on sequence alignment. AlyM2 is a bifunctional endotype lyase, exhibiting the highest activity at 30 °C, pH 8.0, and 0.5 M NaCl. AlyM2 predominantly produces trisaccharides from homopolymeric M block (PM), homopolymeric G block (PG), or sodium alginate, with a trisaccharide production of 588.4 mg/g from sodium alginate, indicating its promising potential in preparing trisaccharides from these polysaccharides.


Assuntos
Alginatos/química , Proteínas de Bactérias , Polissacarídeo-Liases , Pseudoalteromonas/enzimologia , Sargassum/microbiologia , Trissacarídeos/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Polissacarídeo-Liases/química , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo , Pseudoalteromonas/genética , Pseudoalteromonas/isolamento & purificação , RNA Ribossômico 16S
19.
J Dairy Sci ; 105(7): 5587-5599, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35599033

RESUMO

A quantitative proteomic technique based on data-independent acquisition (DIA) was used to analyze differentially expressed caseins of Saanen goat milk samples collected from 3 regions in China (Guangdong, GD; Inner Mongolia, IM; Shaanxi, SX). A total of 345 proteins were quantified in each sample. Gene Ontology (GO) analysis showed that proteins were mainly involved in cellular process and cell and binding functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that proteins were mainly involved in metabolic pathways. Differentially expressed proteins (DEP) between goat milk from 3 comparison groups composed of paired regions were compared and analyzed. The number of DEP was 114, 69, and 79 for GD versus IM, GD versus SX, and IM versus SX, respectively. The GO enrichment analysis of the 3 comparison groups showed that differences were mainly related to the regulation of biological quality, biological regulation, and response to stimulus in terms of biological process; extracellular region for cellular component; and binding function for molecular function. Pathways in which DEP of GD versus IM, GD versus SX, and IM versus SX were mostly protein processing in endoplasmic reticulum for the first 2 groups and metabolic pathways for the last. Protein-protein interaction network analysis demonstrated that the most prominent DEP was heat shock protein 90 ß family member 1 for both the GD versus IM and the GD versus SX groups, and haptoglobin for the IM versus SX group. Data from this study may offer useful information for further investigation of the protein composition of Saanen goat milk and its application in the dairy industry.


Assuntos
Caseínas , Leite , Animais , Caseínas/análise , Ontologia Genética , Cabras/metabolismo , Leite/química , Proteômica/métodos
20.
J Dairy Sci ; 105(5): 3758-3769, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35248379

RESUMO

Monk fruit extract (MFE) is widely used as a sweetener in foods. In this study, the effects of the consumption of MFE-sweetened synbiotic yogurt on the lipid biomarkers and metabolism in the livers of type 2 diabetic rats were evaluated. The results revealed that the MFE-sweetened symbiotic yogurt affected the phosphatidylcholines, phosphatidylethanolamines, phosphatidylglycerol, lysophosphatidic acids, lysophosphatidylcholines, lysophosphatidylethanolamines, lysophosphatidylglycerols, lysophosphatidylinositols, lysophosphatidylserines, and fatty acid-hydroxy fatty acids biomarkers in the livers of type 2 diabetic rats. In addition, the consumption of the MFE-sweetened synbiotic yogurt significantly altered 12 hepatic metabolites, which are involved in phenylalanine metabolism, sphingolipid metabolism, bile secretion, and glyoxylate and dicarboxylate metabolism in the liver. Furthermore, a multiomics (metabolomic and transcriptomic) association study revealed that there was a significant correlation between the MFE-sweetened synbiotic yogurt and the metabolites and genes involved in fatty acid biosynthesis, bile secretion, and glyoxylate and dicarboxylate metabolism. The findings of this study will provide new insights on exploring the function of sweeteners for improving type 2 diabetes mellitus liver lipid biomarkers.


Assuntos
Cucurbitaceae , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Doenças dos Roedores , Simbióticos , Animais , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/veterinária , Ácidos Graxos/metabolismo , Frutas/química , Glioxilatos/metabolismo , Glioxilatos/farmacologia , Metabolismo dos Lipídeos , Lipídeos/farmacologia , Fígado/metabolismo , Extratos Vegetais/farmacologia , Ratos , Doenças dos Roedores/metabolismo , Edulcorantes/análise , Iogurte/análise
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