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1.
Rapid Commun Mass Spectrom ; 38(14): e9716, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38738638

RESUMO

RATIONALE: This study overcomes traditional biomass analysis limitations by introducing a pioneering matrix-free laser desorption/ionization (LDI) approach in mass spectrometry imaging (MSI) for efficient lignin evaluation in wood. The innovative acetic acid-peracetic acid (APA) treatment significantly enhances lignin detection, enabling high-throughput, on-site analysis. METHODS: Wood slices, softwood from a conifer tree (Japanese cypress) and hardwood from a broadleaf tree (Japanese beech), were analyzed using MSI with a Fourier transform ion cyclotron resonance mass spectrometer. The developed APA treatment demonstrated effectiveness for MSI analysis of biomass. RESULTS: Our imaging technique successfully distinguishes between earlywood and latewood and enables the distinct visualization of lignin in these and other wood tissues, such as the radial parenchyma. This approach reveals significant contrasts in MSI. It has identified intense ions from ß-O-4-type lignin, specifically in the radial parenchyma of hardwood, highlighting the method's precision and utility in wood tissue analysis. CONCLUSIONS: The benefits of matrix-free LDI include reduced peak overlap, consistent sample quality, preservation of natural sample properties, enhanced analytical accuracy, and reduced operational costs. This innovative approach is poised to become a standard method for rapid and precise biomass evaluation and has important applications in environmental research and sustainable resource management and is crucial for the effective management of diverse biomass, paving the way towards a sustainable, circular society.


Assuntos
Biomassa , Lignina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Madeira , Madeira/química , Lignina/análise , Lignina/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Fagus/química
2.
Int J Cancer ; 152(12): 2554-2566, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36727538

RESUMO

The efficacy of immune checkpoint inhibitors is limited in refractory solid tumors. T-cell receptor gene-modified T (TCR-T)-cell therapy has attracted attention as a new immunotherapy for refractory cold tumors. We first investigated the preclinical efficacy and mode of action of TCR-T cells combined with the pullulan nanogel:long peptide antigen (LPA) vaccine in a mouse sarcoma model that is resistant to immune checkpoint inhibition. Without lymphodepletion, the pullulan nanogel:LPA vaccine markedly increased the number of TCR-T cells in the draining lymph node and tumor tissue. This change was associated with enhanced CXCR3 expression in TCR-T cells in the draining lymph node. In the phase 1 trial, autologous New York esophageal squamous cell carcinoma 1 (NY-ESO-1)-specific TCR-T cells were infused twice into HLA-matched patients with NY-ESO-1+ soft tissue sarcoma (STS). The pullulan nanogel:LPA vaccine contains an epitope recognized by TCR-T cells, and it was subcutaneously injected 1 day before and 7 days after the infusion of TCR-T cells. Lymphodepletion was not performed. Three patients with refractory synovial sarcoma (SS) were treated. Two out of the three patients developed cytokine release syndrome (CRS) with low-to-moderate cytokine level elevation. We found obvious tumor shrinkage lasting for more than 2 years by tumor imaging and long-term persistence of TCR-T cells in one patient. In conclusion, NY-ESO-1-specific TCR-T-cell therapy plus vaccination with the pullulan nanogel carrying an LPA containing the NY-ESO-1 epitope without lymphodepletion is feasible and can induce promising long-lasting therapeutic effects in refractory SS (Registration ID: JMA-IIA00346).


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Sarcoma Sinovial , Neoplasias de Tecidos Moles , Vacinas , Animais , Camundongos , Nanogéis , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Antígenos de Neoplasias , Sarcoma Sinovial/terapia , Epitopos , Terapia Baseada em Transplante de Células e Tecidos
3.
Biomacromolecules ; 23(3): 789-797, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35034439

RESUMO

Antiviral lignin was produced by acidic microwave glycerolysis of sugarcane bagasse. The lignin exhibited antiviral activity against nonenveloped (encephalomyocarditis virus (EMCV) and Theiler's murine encephalomyelitis virus (TMEV)) and enveloped (vesicular stomatitis virus (VSV), Sindbis virus (SINV), and Newcastle disease virus (NDV)) viruses. A series of lignins with different antiviral activities were prepared by reacting bagasse at 140, 160, 180, and 200 °C to analyze the antiviral mechanism. No difference in ζ-potential was observed among the lignin preparations; however, the lignin prepared at 200 °C (FR200) showed the strongest anti-EMCV activity, smallest hydrodynamic diameter, highest hydrophilicity, and highest affinity for EMCV. FR200 inhibited viral propagation through contact with the virion at the attachment stage to host cells, and the EMCV RNA was intact after treatment. Therefore, the lignin inhibits viral entry to host cells through interactions with the capsid surface. The nonvolatile antiviral substance is potentially useful for preventing the spread of viruses in human living and livestock breeding environments.


Assuntos
Cardiovirus , Saccharum , Animais , Antivirais/farmacologia , Celulose/farmacologia , Vírus da Encefalomiocardite/genética , Humanos , Lignina/farmacologia , Camundongos , Micro-Ondas
4.
Appl Microbiol Biotechnol ; 105(1): 197-210, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33230603

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are auxiliary enzymes catalyzing oxidative cleavages of cellulose chains in crystalline regions, resulting in their increasing accessibility to the hydrolytic enzyme counterparts and hence higher released sugars from biomass saccharification. In this study, a novel auxiliary protein family 9 LPMO (BgAA9) was identified from a metagenomic library derived from a thermophilic microbial community in bagasse collection site where diverse AA9 and AA10 putative sequences were annotated. The enzyme showed highest similarity to a glycoside hydrolase family 61 from Chaetomium thermophilum. Recombinant BgAA9 expressed in Pichia pastoris cleaved cellohexaose (DP6) into shorter cellooligosaccharides (DP2, DP3, and DP4). Supplementation BgAA9 to a commercial cellulase, Accellerase® 1500 showed strong synergistic effect on saccharification of Avicel® PH101, decrystallized cellulose, filter paper, and alkaline-pretreated sugarcane bagasse, resulting in 63-93% increase in the total reducing sugar yield after incubation at 50 °C for 72 h. Strong synergism was shown between BgAA9 and the cellulase with the highest total fermentable sugar yield obtained from 75:25% of Accellerase®1500:BgAA9 which released 39 mg glucose/FPU (filter paper unit) equivalent to 38.7% higher than Accellerase®1500 alone at the same total protein dosage of 5 mg/g substrate according to the mixture design study. The enzyme represented the first characterized LPMO from environmental metagenome and a potent auxiliary component for biomass saccharification. KEY POINTS: • BgAA9 represents the first characterized LPMO from metagenome. • 12 AA families were annotated in thermophilic bagasse fosmid library by NGS. • BgAA9 showed homology to Cel61 in Chaetomium thermophilum. • BgAA9 oxidized cellohexaose and PASC to DP2, DP4, and DP6. • BgAA9 showed strong synergism to Accellerase on bagasse hydrolysis.


Assuntos
Metagenoma , Oxigenases de Função Mista , Celulose , Chaetomium , Oxigenases de Função Mista/genética , Polissacarídeos , Saccharomycetales
5.
Biosci Biotechnol Biochem ; 83(8): 1547-1556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30714483

RESUMO

The basidiomycetous yeast Pseudozyma antarctica GB-4(0) esterase (PaE) is a promising candidate for accelerating degradation of used biodegradable plastics (BPs). To increase safety and reduce costs associated with the use of PaE, we constructed a self-cloning strain with high-PaE productivity. A Lys12 gene (PaLYS12)-deleted lysine auxotroph strain GB4-(0)-L1 was obtained from GB-4(0) by ultraviolet mutagenesis and nystatin enrichment. Subsequently, the PaE gene (PaCLE1) expression cassette consisting of GB-4(0)-derived PaCLE1, under the control of a xylose-inducible xylanase promoter with PaLYS12, was randomly introduced into the GB4-(0)-L1 genome. A PaE high-producing strain, PGB474, was selected from among the transformants by high throughput double-screening based on its ability to degrade emulsified polybutylene succinate-co-adipate. Quantitative PCR revealed that four copies of the PaE gene expression cassette were introduced into the PGB474 genome. PGB474 produced 2.0 g/L of PaE by xylose-fed-batch cultivation using a 3-L jar fermentor for 72 h.


Assuntos
Biodegradação Ambiental , DNA Fúngico/genética , Enzimas/metabolismo , Plásticos/metabolismo , Ustilaginales/genética , Lisina/genética , Mutação , Reação em Cadeia da Polimerase/métodos , Ustilaginales/enzimologia
6.
Fungal Genet Biol ; 109: 7-15, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29030267

RESUMO

Peroxisomes are well-known organelles that are present in most eukaryotic organisms. Mutant phenotypes caused by the malfunction of peroxisomes have been shown in many fungi. However, these have never been investigated in Agaricomycetes, which include white-rot fungi that degrade wood lignin in nature almost exclusively and play an important role in the global carbon cycle. Based on the results of a forward genetics study to identify mutations causing defects in the ligninolytic activity of the white-rot Agaricomycete Pleurotus ostreatus, we report phenotypes of pex1 disruptants in P. ostreatus, which are defective in two major features of white-rot Agaricomycetes: lignin biodegradation and mushroom formation. Pex1 disruption was also shown to cause defects in the hyphal growth of P. ostreatus on certain sawdust and minimum media. We also demonstrated that pex1 is essential for fruiting initiation in the non-wood decaying Agaricomycete Coprinopsis cinerea. However, unlike P. ostreatus, significant defects in hyphal growth on the aforementioned agar medium were not observed in C. cinerea. This result, together with previous C. cinerea genetic studies, suggests that the regulation mechanisms for the utilization of carbon sources are altered during the evolution of Agaricomycetes or Agaricales.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Carbono/metabolismo , Coprinus/metabolismo , Proteínas Fúngicas/metabolismo , Lignina/metabolismo , Peroxissomos/metabolismo , Pleurotus/metabolismo , ATPases Associadas a Diversas Atividades Celulares/genética , Evolução Biológica , Biotransformação , Coprinus/genética , Coprinus/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Genes Fúngicos , Mutagênese , Peroxissomos/genética , Pleurotus/genética , Pleurotus/crescimento & desenvolvimento
7.
Am J Orthod Dentofacial Orthop ; 152(4): 483-488, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28962732

RESUMO

INTRODUCTION: Approximately 14% of orthodontic anchor screws (miniscrews) become dislodged regardless of the accuracy of placement. It is therefore important to investigate the factors causing dislodgement. We evaluated the stability of miniscrews after placement to identify factors influencing outcome in orthodontic treatment using miniscrews. METHODS: We investigated 120 miniscrews (Dual-top Auto Screw III; Jeil Medical, Seoul, Korea) (diameter, 1.4 mm; length, 6 mm) placed on the buccal or lingual side between the maxillary second premolar and the first molar in women. Patient age and rate and time of screw dislodgement were examined. Insertion torque values and Periotest (Tokyo Dental Industrial, Tokyo, Japan) measurements indicating horizontal and vertical mobility of the inserted screws were compared between groups with and without dislodgement (failure and success groups, respectively). RESULTS: Mean insertion torque values were 10.7 ± 1.9 N·cm and 8.5 ± 2.1 N·cm in the failure and success groups, respectively. Cortical bone thickness measurements (success group, 1.34 ± 0.35 mm; failure group, 0.99 ± 0.09 mm) were significantly higher, whereas Periotest values at placement (success group, horizontal, 4.9 ± 1.4; vertical, 4.7 ± 1.3; failure group, horizontal, 7.0 ± 0.8; vertical, 7.1 ± 0.9) were significantly lower in the success group than in the failure group. CONCLUSIONS: The Periotest value, together with insertion torque and cortical bone thickness, could serve as an index of initial stability for predicting the outcome of miniscrew placement.


Assuntos
Aparelhos Ortodônticos , Adulto , Parafusos Ósseos , Feminino , Humanos , Desenho de Aparelho Ortodôntico , Valor Preditivo dos Testes , Implantação de Prótese/métodos , Torque , Resultado do Tratamento
8.
Appl Microbiol Biotechnol ; 100(7): 3207-17, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26695155

RESUMO

Yeast host-vector systems are useful tools for the production of recombinant proteins. Here, we report the construction of a new high-level expression plasmid pPAX1-neo for the basidiomycetous yeast, Pseudozyma antarctica. pPAX1-neo harbours a xylose-inducible expression cassette under control of the xylanase promoter and terminator of P. antarctica T-34, a selection cassette of neomycin/G418 with an Escherichia coli neomycin resistance gene under control of the homocitrate synthase promoter of strain T-34, and an autonomously replicating sequence fragment of Ustilago maydis (UARS). Biodegradable plastic (BP)-degrading enzymes of P. antarctica JCM10317 (PaE) and Paraphoma-related fungal strain B47-9 (PCLE) were used as reporter proteins and inserted into pPAX1-neo, resulting in pPAX1-neo::PaCLE1 and pPAX1-neo::PCLE, respectively. Homologous and heterologous BP-degrading enzyme production of transformants of P. antarctica T-34 were detected on agar plates containing xylose and emulsified BP. Recombinant PaE were also produced by transformants of other Pseudozyma strains including Pseudozyma aphidis, Pseudozyma rugulosa, and Pseudozyma tsukubaensis. To improve the stability of transformed genes in cells, the UARS fragment was removed from linearized pPAX1-neo::PaCLE1 and integrated into the chromosome of the P. antarctica strain, GB-4(0), which was selected as a PaE producer in xylose media. Two transformants, GB-4(0)-X14 and X49, had an 11-fold higher activity compared with the wild type strain in xylose-containing liquid media. By xylose fed-batch cultivation using a 3-L jar fermentor, GB-4(0)-X14 produced 73.5 U mL(-1) of PaE, which is 13.4-fold higher than that of the wild type strain GB-4(0), which produced 5.5 U mL(-1) of PaE.


Assuntos
Plásticos Biodegradáveis/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Proteínas Fúngicas/biossíntese , Oxo-Ácido-Liases/metabolismo , Ustilaginales/enzimologia , Xilose/metabolismo , Técnicas de Cultura Celular por Lotes , Biodegradação Ambiental , Reatores Biológicos , Cromossomos Fúngicos/química , Cromossomos Fúngicos/metabolismo , Endo-1,4-beta-Xilanases/genética , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas Fúngicas/genética , Expressão Gênica , Neomicina , Oxo-Ácido-Liases/genética , Plasmídeos/química , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Engenharia de Proteínas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Transgenes , Ustilaginales/genética
9.
Proc Natl Acad Sci U S A ; 109(14): 5458-63, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22434909

RESUMO

Efficient lignin depolymerization is unique to the wood decay basidiomycetes, collectively referred to as white rot fungi. Phanerochaete chrysosporium simultaneously degrades lignin and cellulose, whereas the closely related species, Ceriporiopsis subvermispora, also depolymerizes lignin but may do so with relatively little cellulose degradation. To investigate the basis for selective ligninolysis, we conducted comparative genome analysis of C. subvermispora and P. chrysosporium. Genes encoding manganese peroxidase numbered 13 and five in C. subvermispora and P. chrysosporium, respectively. In addition, the C. subvermispora genome contains at least seven genes predicted to encode laccases, whereas the P. chrysosporium genome contains none. We also observed expansion of the number of C. subvermispora desaturase-encoding genes putatively involved in lipid metabolism. Microarray-based transcriptome analysis showed substantial up-regulation of several desaturase and MnP genes in wood-containing medium. MS identified MnP proteins in C. subvermispora culture filtrates, but none in P. chrysosporium cultures. These results support the importance of MnP and a lignin degradation mechanism whereby cleavage of the dominant nonphenolic structures is mediated by lipid peroxidation products. Two C. subvermispora genes were predicted to encode peroxidases structurally similar to P. chrysosporium lignin peroxidase and, following heterologous expression in Escherichia coli, the enzymes were shown to oxidize high redox potential substrates, but not Mn(2+). Apart from oxidative lignin degradation, we also examined cellulolytic and hemicellulolytic systems in both fungi. In summary, the C. subvermispora genetic inventory and expression patterns exhibit increased oxidoreductase potential and diminished cellulolytic capability relative to P. chrysosporium.


Assuntos
Basidiomycota/genética , Genômica , Lignina/metabolismo , Basidiomycota/classificação , Hidrólise , Dados de Sequência Molecular , Oxirredução , Filogenia , Especificidade da Espécie
10.
Tohoku J Exp Med ; 237(2): 83-90, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26377351

RESUMO

In March 2011, the Great East Japan Earthquake (GEJE), which was followed by a devastating tsunami, destroyed the societal and the public hygiene systems in Japanese coastal areas. Insomnia, the greatest issue among disaster victims, has detrimental effects on both physical and psychological health. Periodontitis causes chronic discomfort and inflammation, and little is known about its impact on insomnia. Three months after the earthquake, a health panel survey was conducted over four surveys, till September 2013, in which information regarding 8,015 adults was collected and used. In addition to the heath-related questionnaire, other variables including subjective symptoms of oral diseases were recorded, and the Athens Insomnia Scale was used to evaluate the severity of insomnia. The association between insomnia and periodontal disease was examined using multilevel logistic models on the panel data, after adjusting for sex, age, economic status, comorbidities, body mass index, post-traumatic stress reactions, habitual smoking and alcohol drinking, and the Kessler Psychological Distress Scale score. In addition to the higher prevalence of insomnia among GEJE victims, significant association was revealed between insomnia and gum problems (OR = 2.16, 95% CI = 1.43-3.26), and difficulty chewing (OR = 2.22, 95% CI = 1.40-3.51), after adjusting for all covariates. The present study revealed significant association between insomnia and periodontal disease among GEJE victims. This indicated that together, integrated oral health care for disaster victims would contribute not only to prevention of oral infectious diseases, but may also help alleviate other problems caused by these harmful events.


Assuntos
Terremotos , Doenças Periodontais/complicações , Distúrbios do Início e da Manutenção do Sono/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Inquéritos Epidemiológicos , Humanos , Japão/epidemiologia , Masculino , Mastigação , Pessoa de Meia-Idade , Doenças Periodontais/epidemiologia , Prevalência , Fatores de Risco , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Fatores Socioeconômicos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Inquéritos e Questionários , Doenças Dentárias/epidemiologia , Tsunamis , Adulto Jovem
11.
J Biol Chem ; 288(19): 13821-30, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23530038

RESUMO

BACKGROUND: Plant pathogens secrete enzymes that degrade plant cell walls to enhance infection and nutrient acquisition. RESULTS: A novel endotransglucosylase catalyzes cleavage and transfer of ß-glucans and decreases the physical strength of plant cell walls. CONCLUSION: Endotransglucosylation causes depolymerization and polymerization of ß-glucans, depending on substrate molecular size. SIGNIFICANCE: Enzymatic degradation of plant cell walls is required for wall loosening, which enhances pathogen invasion. A Magnaporthe oryzae enzyme, which was encoded by the Mocel7B gene, was predicted to act on 1,3-1,4-ß-glucan degradation and transglycosylation reaction of cellotriose after partial purification from a culture filtrate of M. oryzae cells, followed by liquid chromatography-tandem mass spectrometry. A recombinant MoCel7B prepared by overexpression in M. oryzae exhibited endo-typical depolymerization of polysaccharides containing ß-1,4-linkages, in which 1,3-1,4-ß-glucan was the best substrate. When cellooligosaccharides were used as the substrate, the recombinant enzyme generated reaction products with both shorter and longer chain lengths than the substrate. In addition, incorporation of glucose and various oligosaccharides including sulforhodamine-conjugated cellobiose, laminarioligosaccharides, gentiobiose, xylobiose, mannobiose, and xyloglucan nonasaccharide into ß-1,4-linked glucans were observed after incubation with the enzyme. These results indicate that the recombinant enzyme acts as an endotransglucosylase (ETG) that cleaves the glycosidic bond of ß-1,4-glucan as a donor substrate and transfers the cleaved glucan chain to another molecule functioning as an acceptor substrate. Furthermore, ETG treatment caused greater extension of heat-treated wheat coleoptiles. The result suggests that ETG functions to induce wall loosening by cleaving the 1,3-1,4-ß-glucan tethers of plant cell walls. On the other hand, use of cellohexaose as a substrate for ETG resulted in the production of cellulose II with a maximum length (degree of polymerization) of 26 glucose units. Thus, ETG functions to depolymerize and polymerize ß-glucans, depending on the size of the acceptor substrate.


Assuntos
Proteínas Fúngicas/química , Glicosídeo Hidrolases/química , Magnaporthe/enzimologia , beta-Glucanas/metabolismo , Configuração de Carboidratos , Parede Celular/química , Celulose/biossíntese , Clonagem Molecular , Cotilédone/química , Cotilédone/citologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Hidrólise , Oligossacarídeos/química , Oryza/microbiologia , Folhas de Planta/microbiologia , Especificidade por Substrato , Transcrição Gênica , Triticum/química , Triticum/citologia
12.
Appl Microbiol Biotechnol ; 98(14): 6419-29, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24706213

RESUMO

The biological function of mannosylerythritol lipids (MELs) towards their producer, Pseudozyma antarctica, on plant surfaces was investigated. MEL-producing wild-type strain and its MEL production-defective mutant strain (ΔPaEMT1) were compared in terms of their phenotypic traits on the surface of plastic plates, onion peels, and fresh leaves of rice and wheat. While wild-type cells adhering on plastic surfaces and onion peels changed morphologically from single cells to elongated ones for a short period of about 4 h and 1 day, respectively, ΔPaEMT1 cells did not. Microscopic observation of both strains grown on plant leaf surfaces verified that the wild type colonized a significantly bigger area than that of ΔPaEMT1. However, when MELs were exogenously added to the mutant cells on plant surfaces, their colonized area became enlarged. High-performance liquid chromatography analysis revealed a secretion of higher amount of MELs in the cell suspension incubated with wheat leaf cuttings compared to that in the suspension without cuttings. Transcriptional analysis by real-time reverse transcriptase PCR verified that the expression of erythritol/mannose transferase gene and MELs transporter gene of P. antarctica increased in the cells inoculated onto wheat leaves at 4, 6, and 8 days of incubation, indicating a potential of P. antarctica to produce MELs on the leaves. These findings demonstrate that MELs produced by P. antarctica on plant surfaces could be expected to play a significant role in fungal morphological development and propagation on plant surfaces.


Assuntos
Glicolipídeos/metabolismo , Folhas de Planta/microbiologia , Ustilaginales/crescimento & desenvolvimento , Ustilaginales/metabolismo , Adesão Celular , Perfilação da Expressão Gênica , Glucosiltransferases/análise , Proteínas de Membrana Transportadoras/metabolismo , Microscopia , Cebolas , Oryza , Plásticos , Fatores de Tempo , Triticum , Ustilaginales/citologia , Ustilaginales/fisiologia
13.
Environ Microbiol Rep ; 16(1): e13210, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37950419

RESUMO

The MBES04 strain of Novosphingobium accumulates phenylpropanone monomers as end-products of the etherase system, which specifically and reductively cleaves the ß-O-4 ether bond (a major bond in lignin molecules). However, it does not utilise phenylpropanone monomers as an energy source. Here, we studied the response to the lignin-related perturbation to clarify the physiological significance of its etherase system. Transcriptome analysis revealed two gene clusters, each consisting of four tandemly linked genes, specifically induced by a lignin preparation extracted from hardwood (Eucalyptus globulus) and a ß-O-4-type lignin model biaryl compound, but not by vanillin. The most strongly induced gene was a 2,4'-dihydroxyacetophenone dioxygenase-like protein, which leads to energy production through oxidative degradation. The other cluster was related to multidrug resistance. The former cluster was transcriptionally regulated by a common promoter, where a phenylpropanone monomer acted as one of the effectors responsible for gene induction. These results indicate that the physiological significance of the etherase system of the strain lies in its function as a sensor for lignin fragments. This may be a survival strategy to detect nutrients and gain tolerance to recalcitrant toxic compounds, while the strain preferentially utilises easily degradable aromatic compounds with lower energy demands for catabolism.


Assuntos
Hidrocarbonetos Fluorados , Lignina , Sphingomonadaceae , Lignina/química , Proteínas de Bactérias/genética , Oxirredução , Éteres/química , Éteres/metabolismo , Sphingomonadaceae/genética , Sphingomonadaceae/metabolismo
14.
J Agric Food Chem ; 72(5): 2657-2666, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38288662

RESUMO

Rice straw (RS), an agricultural residue rich in carbohydrates, has substantial potential for bioethanol production. However, the presence of lignin impedes access to these carbohydrates, hindering efficient carbohydrate-to-bioethanol conversion. Here, we expressed versatile peroxidase (VP), a lignin-degrading enzyme, in Pichia pastoris and used it to delignify RS at 30 °C using a membrane bioreactor that continuously discarded the degraded lignin. Klason lignin analysis revealed that VP-treatment led to 35% delignification of RS. We then investigated the delignified RS by SEC, FTIR, and SEM. The results revealed the changes of RS caused by VP-mediated delignification. Additionally, we compared the saccharification and fermentation yields between RSs treated with and without VP, VP-RS, and Ctrl-RS, respectively. This examination unveiled an improvement in glucose and bioethanol production, VP-RS exhibiting up to 1.5-fold and 1.4-fold production, respectively. These findings underscore the potential of VP for delignifying RS and enhancing bioethanol production through an eco-friendly approach.


Assuntos
Lignina , Oryza , Lignina/química , Oryza/química , Peroxidase/metabolismo , Carboidratos/química , Peroxidases/metabolismo , Fermentação , Hidrólise
15.
Appl Microbiol Biotechnol ; 97(17): 7679-88, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23224497

RESUMO

Two yeast strains, which have the ability to degrade biodegradable plastic films, were isolated from the larval midgut of a stag beetle, Aegus laevicollis. Both of them are most closely related to Cryptococcus magnus and could degrade biodegradable plastic (BP) films made of poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA) effectively. A BP-degrading enzyme was purified from the culture broth of one of the isolated strains employing a newly developed affinity purification method based on the binding action of the enzyme to the substrate (emulsified PBSA) and its subsequent degradative action toward the substrate. Partial amino acid sequences of this enzyme suggested that it belongs to the cutinase family, and thus, the enzyme was named CmCut1. It has a molecular mass of 21 kDa and a degradative activity for emulsified PBSA which was significantly enhanced by the simultaneous presence of Ca(2+) or Mg(2+) at a concentration of about 2.5 mM. Its optimal pH was 7.5, and the optimal temperature was 40 °C. It showed a broad substrate specificity for p-nitrophenyl (pNP)-fatty acid esters ranging from pNP-acetate (C2) to pNP-stearate (C18) and films of PBSA, PBS, poly(ε-caprolactone), and poly(lactic acid).


Assuntos
Plásticos Biodegradáveis/metabolismo , Besouros/microbiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Leveduras/enzimologia , Leveduras/isolamento & purificação , Adipatos/metabolismo , Sequência de Aminoácidos , Animais , Butileno Glicóis/metabolismo , Cromatografia de Afinidade , Besouros/crescimento & desenvolvimento , Estabilidade Enzimática , Proteínas Fúngicas/genética , Trato Gastrointestinal/microbiologia , Larva/microbiologia , Dados de Sequência Molecular , Peso Molecular , Polímeros/metabolismo , Alinhamento de Sequência , Especificidade por Substrato , Succinatos/metabolismo , Leveduras/química , Leveduras/metabolismo
16.
Appl Microbiol Biotechnol ; 97(19): 8591-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23339012

RESUMO

Enzymatic degradation of polyester films by a cutinase-like enzyme from Pseudozyma antarctica JCM10317 (PaE) was analyzed by surface plasmon resonance (SPR). The adsorption of PaE and the degradation rate for polyester films were quantitatively monitored by a positive and negative SPR signal shifts, respectively. The decrease in SPR signal and the erosion depth of amorphous poly(L-lactide) (a-PLLA) film measured by atomic force microscopy (AFM) had a linear relationship, and the weight loss was estimated from the AFM data combined with a density of a-PLLA film. Furthermore, SPR sensorgrams for various polyester films showed that degradation rate of poly(ε-caprolactone) and poly(butylene succinate-co-adipate) which contain C6 units was higher than that of other polyesters such as poly(butylene succinate) and a-PLLA. These results suggest that C6 is the preferred chain length as substrates for PaE.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Poliésteres/metabolismo , Ustilaginales/enzimologia , Microscopia de Força Atômica , Especificidade por Substrato , Ressonância de Plasmônio de Superfície
17.
Appl Microbiol Biotechnol ; 97(7): 2951-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22678026

RESUMO

Pseudozyma antarctica JCM 10317 exhibits a strong degradation activity for biodegradable plastics (BPs) such as agricultural mulch films composed of poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA). An enzyme named PaE was isolated and the gene encoding PaE was cloned from the strain by functional complementation in Saccharomyces cerevisiae. The deduced amino acid sequence of PaE contains 198 amino acids with a predicted molecular weight of 20,362.41. High identity was observed between this sequence and that of cutinase-like enzymes (CLEs) (61-68%); therefore, the gene encoding PaE was named PaCLE1. The specific activity of PaE against emulsified PBSA was 54.8±6.3 U/mg. In addition to emulsified BPs, PaE degraded solid films of PBS, PBSA, poly(ε-caprolactone), and poly(lactic acid).


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Plásticos/metabolismo , Ustilaginales/enzimologia , Adipatos/metabolismo , Sequência de Aminoácidos , Biotransformação , Butileno Glicóis/metabolismo , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/genética , Clonagem Molecular , DNA Fúngico/química , DNA Fúngico/genética , Dados de Sequência Molecular , Peso Molecular , Polímeros/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Succinatos/metabolismo , Ustilaginales/genética
18.
J Prosthet Dent ; 110(6): 435-41, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24267586

RESUMO

Orthodontic extrusion of nonrestorable teeth has been used for almost 20 years as an alternative to bone grafting in preparation for implant placement. Although this technique predictably creates bone and soft tissue, and improves the socket diameter and depth, most of the bone apposition occurs in the marginal alveolar and periapical areas of the extruded tooth. To create more labial bone, the standard orthodontic extrusion technique was modified to apply pressure on the hopeless tooth both coronally and palatally, which allowed bone at the site to develop apically and labially. Gingival thickness on the labial aspect was also increased, and the tissue biotype was improved. A clinical treatment is presented that illustrates the use of this technique.


Assuntos
Processo Alveolar/crescimento & desenvolvimento , Implantes Dentários , Estética Dentária , Gengiva/crescimento & desenvolvimento , Extrusão Ortodôntica/métodos , Alvéolo Dental/crescimento & desenvolvimento , Adulto , Perda do Osso Alveolar/terapia , Remodelação Óssea/fisiologia , Implantação Dentária Endóssea/métodos , Seguimentos , Retração Gengival/terapia , Regeneração Tecidual Guiada Periodontal/métodos , Humanos , Incisivo/patologia , Incisivo/cirurgia , Masculino , Desenho de Aparelho Ortodôntico , Extrusão Ortodôntica/instrumentação , Fios Ortodônticos , Extração Dentária/métodos
19.
J Neurosurg Case Lessons ; 6(10)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37728240

RESUMO

BACKGROUND: Ameloblastic carcinoma (AC) is a rare odontogenic carcinoma with histological features resembling ameloblastoma. Metastasis to distant organs and direct expansion into the skull base structures are associated with a poor clinical outcome. This rare case of AC metastasis to the pituitary gland presented without local recurrence at the primary focus of the maxilla. OBSERVATIONS: A 47-year-old man had a 2-year history of AC in the right maxilla. Computed tomography for his regular checkup incidentally demonstrated pituitary tumor, rapidly growing over 2 months. He presented with the recent onset of panhypopituitarism and visual field defect. Magnetic resonance imaging showed a large, irregularly shaped intrasellar and suprasellar lesion with chiasmal compression. Endoscopic endonasal transsphenoidal surgery was performed for decompression of the optic apparatus to avoid intracranial spread. Histopathology confirmed metastatic AC, and a genetic panel test confirmed BRAF V600E mutation. Stereotactic radiotherapy (SRT) with the CyberKnife system was administered to the residual tumor. Remarkable tumor shrinkage was obtained, and panhypopituitarism was resolved 12 months later. LESSONS: A multidisciplinary treatment strategy including maximal safe resection to avoid dissemination in combination with SRT may be crucial for local control with the preservation of pituitary and visual functions in patients with solitary pituitary metastatic AC.

20.
Sci Rep ; 13(1): 2386, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36765090

RESUMO

Biodegradable plastics can solve the problem of unwanted plastics accumulating in the environment if they can be given the contradictory properties of durability in use and rapid degradation after use. Commercially available agricultural biodegradable mulch films are made from formulations containing polybutylene adipate-co-terephthalate (PBAT) to provide mechanical and UV resistance during the growing season. Although used films are ploughed into the soil using a tiller to promote decomposition, it is difficult if they remain durable. We showed that an enzyme produced by the leaf surface yeast Pseudozyma antarctica (PaE) degrades PBAT-containing films. In laboratory studies, PaE randomly cleaved the PBAT polymer chain and induced erosion of the film surface. In the field, commercial biodegradable films containing PBAT placed on ridges were weakened in both the warm and cold seasons by spraying the culture filtrate of P. antarctica. After the field was ploughed the next day, the size and total weight of residual film fragments decreased significantly (p < 0.05). Durable biodegradable plastics used in the field are degraded using PaE treatment and are broken down into small fragments by the plough. The resultant degradation products can then be more readily assimilated by many soil microorganisms.


Assuntos
Plásticos Biodegradáveis , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Polímeros/metabolismo , Solo , Agricultura
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