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1.
Mol Ther ; 32(6): 1805-1816, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38532628

RESUMO

The novel coronavirus disease 2019 has stimulated the rapid development of new biological therapeutics to inhibit SARS-CoV-2 infection; however, this remains a challenging task. In a previous study using structural analysis, we revealed that human cyclophilin A inhibits the entry of SARS-CoV-2 into host cells by interfering with the interaction of the receptor-binding domain of the spike protein with angiotensin-converting enzyme 2 on the host cell surface, highlighting its potential for antiviral therapy. For a comprehensive experimental validation, in this study, we verified the antiviral effects of human cyclophilin A against SARS-CoV-2, including its variants, using in vitro assays and experiments on an in vivo mouse model. Human cyclophilin A demonstrated a highly effective antiviral effect, with an 85% survival rate upon SARS-CoV-2 infection. It also reduced viral titers, inflammation in the lungs and brain, and cytokine release in the serum, suggesting a controlled immune response and potentially faster recovery. Overall, our study provides insights into the potential of human cyclophilin A as a therapeutic agent against SARS-CoV-2, which should guide future clinical trials that might provide an additional therapeutic option for patients.


Assuntos
Antivirais , COVID-19 , Ciclofilina A , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , SARS-CoV-2/efeitos dos fármacos , Humanos , Ciclofilina A/metabolismo , Camundongos , Antivirais/farmacologia , COVID-19/virologia , COVID-19/metabolismo , Ligação Proteica , Tratamento Farmacológico da COVID-19 , Enzima de Conversão de Angiotensina 2/metabolismo , Modelos Animais de Doenças , Células Vero , Chlorocebus aethiops , Feminino
2.
J Nanobiotechnology ; 22(1): 6, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167116

RESUMO

With the immense progress in drug delivery systems (DDS) and the rise of nanotechnology, challenges such as target specificity remain. The vesicle-vector system (VVS) is a delivery system that uses lipid-based vesicles as vectors for a targeted drug delivery. When modified with target-probing materials, these vesicles become powerful vectors for drug delivery with high target specificity. In this review, we discuss three general types of VVS based on different modification strategies: (1) vesicle-probes; (2) vesicle-vesicles; and (3) genetically engineered vesicles. The synthesis of each VVS type and their corresponding properties that are advantageous for targeted drug delivery, are also highlighted. The applications, challenges, and limitations of VVS are briefly examined. Finally, we share a number of insights and perspectives regarding the future of VVS as a targeted drug delivery system at the nanoscale.


Assuntos
Vesículas Extracelulares , Sistemas de Liberação de Medicamentos , Nanotecnologia
3.
J Cell Biochem ; 124(1): 59-71, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36302152

RESUMO

The vacuoles of the yeast Saccharomyces cerevisiae are closely related to mammalian lysosomes and play a role in macromolecular degradation due to the hydrolytic enzymes present inside. The vacuoles also regulate osmotic pressure and control cellular homeostasis. In previous results, vacuoles were shown to activate the immune response of macrophages by promoting the production of immune-mediated transporters nitric oxide (NO), reactive oxygen species (ROS), and pro-inflammatory cytokines. In this study, the effects of vacuoles on the phagocytosis activity of RAW264.7 cells and their potential as immune enhancers were evaluated, and receptors capable of recognizing vacuoles were examined. An investigation using the phagocytes assay showed that phagocytosis activity increased by the vacuole. Besides, after treatment with TLR2/4 inhibitor, the expression of pro-inflammatory cytokines by vacuoles was significantly reduced and the inducible nitric oxide synthase (iNOS) protein was also significantly reduced. However, treatment with a TLR2 inhibitor did not reduce the production of interleukin-6 (IL)-6, a pro-inflammatory cytokine. As a result of confirming the activation of TLR2/4 using Western blot and immunofluorescence (IF), the TLR2/4 protein expression and fluorescence intensity increased depending on the concentration of vacuoles. Yeast vacuoles significantly upregulate protein expression of p-p65/p-p38 MAPKs. In summary, the vacuoles isolated from S. cerevisiae in macrophages have increased phagocytic ability at a concentration of 20 (µg/ml) and can function as immune-enhancing agent suggesting that TLR2/4 mediated the p38 MAPK/nuclear factor kappa B signaling pathway.


Assuntos
Fagocitose , Saccharomyces cerevisiae , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Animais , Citocinas/metabolismo , Lipopolissacarídeos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Saccharomyces cerevisiae/metabolismo , Receptor 2 Toll-Like/metabolismo , Vacúolos/metabolismo , Camundongos , Células RAW 264.7 , Receptor 4 Toll-Like/metabolismo
4.
Biomacromolecules ; 24(11): 4915-4922, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37861681

RESUMO

In this study, we aimed to develop an efficient drug delivery system by reassembling vacuoles isolated from Saccharomyces cerevisiae. Initially, we assessed the impact of vacuolar enzymes on the efficacy of the loaded antibiotic polymyxin B (PMB), by conducting antibacterial activity tests using Shigella flexneri and Salmonella enteritidis. The results showed that vacuolar enzymes inhibited the effectiveness of PMB, highlighting the limitations of using natural vacuoles as drug carriers. To overcome this, we proposed a new drug delivery system called reassembled vacuoles (ReV). ReV particles were created by removing vacuolar enzymes and reassembling the vacuolar membrane through extrusion. ReV demonstrated improved structural stability, a more uniform size, and enhanced PMB release compared to natural vacuoles. Encapsulation efficiency tests revealed high loading efficiency for both normal vacuoles (NorV) and ReV, with over 80% efficiency at concentrations up to 600 µg/mL. The antibacterial activity of PMB-loaded ReV showed comparable results to PMB alone, indicating the potential of ReV as a drug delivery system. In conclusion, reassembled vacuoles offer a promising approach for drug delivery, addressing the limitations of natural vacuoles and providing opportunities for targeted and efficient drug release.


Assuntos
Portadores de Fármacos , Saccharomyces cerevisiae , Vacúolos/química , Antibacterianos/farmacologia , Polimixina B/farmacologia , Sistemas de Liberação de Medicamentos
5.
J Biochem Mol Toxicol ; 37(10): e23447, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37368822

RESUMO

Triclosan has been widely used as an antimicrobial agent. However, triclosan was found to cause toxicity, including muscle contraction disturbances, carcinogenesis, and endocrine disorders. In addition, it was found to affect central nervous system function adversely and even have ototoxic effects. Conventional methods for detecting such triclosan can be performed easily. However, the conventional detection methods are inadequate in precisely reflecting the impact of toxic substances on stressed organisms. Therefore, a test model for the toxic environment at the molecular level through the organism is needed. From that point of view, Daphnia magna is being used as a ubiquitous model. D. magna has the advantages of easy cultivation, a short lifespan and high reproductive capacity, and high sensitivity to chemicals. Therefore, the protein expression pattern of D. magna that appear in response to chemicals can be utilized as biomarkers for detecting specific chemicals. In this study, we characterized the proteomic response of D. magna following triclosan exposure via two-dimensional (2D) gel electrophoresis. As a result, we confirmed that triclosan exposure completely suppressed D. magna 2-domain hemoglobin protein and evaluated this protein as a biomarker for triclosan detection. We constructed the HeLa cells in which the GFP gene was controlled by D. magna 2-domain hemoglobin promoter, which under normal conditions, expressed GFP, but upon triclosan exposure, suppressed GFP expression. Consequently, we consider that the HeLa cells containing the pBABE-HBF3-GFP plasmid developed in this study can be used as novel biomarkers for triclosan detection.


Assuntos
Triclosan , Poluentes Químicos da Água , Animais , Humanos , Triclosan/toxicidade , Daphnia/genética , Daphnia/metabolismo , Células HeLa , Proteômica , Poluentes Químicos da Água/farmacologia , Hemoglobinas/metabolismo , Biomarcadores/metabolismo
6.
Ecotoxicol Environ Saf ; 254: 114735, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36907088

RESUMO

Salmonella is a well-known bacterium that causes waterborne diseases in humans and primates. The need for test models to detect such pathogens and study the responses of such organisms to induced toxic environments is vital. Daphnia magna has been ubiquitously used in aquatic life monitoring for decades because of outstanding properties, such as facile cultivation, short lifespan, and high reproductive capacity. In this study, the proteomic response of D. magna exposed to four Salmonella strains (Salmonella dublin, Salmonella enteritidis, Salmonella enterica, and Salmonella typhimurium) was characterized. As indicated by two-dimensional gel electrophoresis, vitellogenin fused with superoxide dismutase was completely suppressed under exposure to S. dublin. Thus, we evaluated the feasibility of using the vitellogenin 2 gene as a biomarker for S. dublin detection, particularly in providing rapid, visual detection through fluorescent signals. Accordingly, the applicability of the HeLa cells transfected with pBABE-Vtg2B-H2B-GFP as a biomarker for the detection of S. dublin was evaluated, and it was confirmed that the fluorescence signal decreased only when S. dublin was treated. Therefore, such HeLa cells can be utilized as a novel biomarker for detecting S. dublin.


Assuntos
Daphnia , Vitelogeninas , Animais , Humanos , Daphnia/genética , Vitelogeninas/genética , Células HeLa , Proteômica , Salmonella typhimurium/genética
7.
Ecotoxicol Environ Saf ; 264: 115446, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688866

RESUMO

Concerns over the spread of non-native species in aquatic environments have led to the need for effective methods to prevent and control their spread while protecting native species. This study investigated the potential of yeast vacuolar enzymes as a natural hatching inhibitor for controlling aquatic organisms. Hatching experiments with Daphnia magna eggs demonstrated that exposure to yeast vacuole enzymes inhibited hatching in a concentration-dependent manner, suggesting their potential as an effective inhibitor of egg hatching in aquatic organisms. Interestingly, the protease used for comparative purposes did not inhibit hatching, but instead increased the mortality of hatched D. magna. Additionally, chorionic changes were observed in non-hatched D. magna eggs and zebrafish eggs exposed to yeast vacuole enzymes, suggesting that the enzyme can alter the chorion and interfere with hatching. These findings suggest that yeast vacuolar enzymes may be a promising and natural management tool for controlling the spread of harmful aquatic organisms, and further research is warranted to explore their potential for species-specific control.


Assuntos
Saccharomyces cerevisiae , Peixe-Zebra , Animais , Daphnia , Organismos Aquáticos , Vacúolos
8.
J Nanobiotechnology ; 20(1): 204, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477501

RESUMO

BACKGROUND: Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, is a biomarker of hepatocellular carcinoma (HCC) progression. Aptamers specifically binding to target biomolecules have recently emerged as clinical disease diagnosis targets. Here, we describe 3D structure-based aptaprobe platforms for detecting GPC3, such as aptablotting, aptaprobe-based sandwich assay (ALISA), and aptaprobe-based imaging analysis. RESULTS: For preparing the aptaprobe-GPC3 platforms, we obtained 12 high affinity aptamer candidates (GPC3_1 to GPC3_12) that specifically bind to target GPC3 molecules. Structure-based molecular interactions identified distinct aptatopic residues responsible for binding to the paratopic nucleotide sequences (nt-paratope) of GPC3 aptaprobes. Sandwichable and overlapped aptaprobes were selected through structural analysis. The aptaprobe specificity for using in HCC diagnostics were verified through Aptablotting and ALISA. Moreover, aptaprobe-based imaging showed that the binding property of GPC3_3 and their GPC3 specificity were maintained in HCC xenograft models, which may indicate a new HCC imaging diagnosis. CONCLUSION: Aptaprobe has the potential to be used as an affinity reagent to detect the target in vivo and in vitro diagnosing system.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Glipicanas/metabolismo , Humanos , Neoplasias Hepáticas/patologia
9.
Appl Microbiol Biotechnol ; 105(23): 8715-8725, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34724081

RESUMO

All eukaryotes have lysosomes that contain hydrolytic enzymes, such as protease, that degrade waste materials and cellular fragments. As a cellular organelle, lysosomes function as the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself. In a previous study, melanin compounds were bleached using lysosome-related organelle extract (LOE) in which glutathione peroxidase (GPX) contributed decisively to melanin decolorization. In this study, Saccharomyces cerevisiae was engineered to overproduce GPX, which increases the melanin color reduction activity of LOE. In addition, the peroxidase activity of the recombinant yeast was measured for each compartment. In spite of the modification to overexpress the GPX protein, with the peroxidase activity of the lysosome fraction specifically higher, the overall peroxidase activity of the cells remained constant. The overexpression of GPX2 among the GPX present in S. cerevisiae increased both the melanin-decolorization activity and the peroxidase activity of LOE. These results indicate that the peroxidase activity is related to the melanin decomposition and antioxidant enzymes such as GPX. In an artificial skin tissue test, the LOE extracted from the recombinant yeast was efficient in reducing the melanin. These results confirmed the enzyme's ability to penetrate corneous tissue, and they suggest the possibility of further development as a new whitening cosmetic. KEY POINTS: • Modification of Saccharomyces cerevisiae to overexpress glutathione peroxidase (GPX). • The lysosome fraction of the recombinant strain enhanced the decolorizing function. • The LOE penetrates the skin barrier and works effectively on artificial skin tissue.


Assuntos
Glutationa Peroxidase/biossíntese , Melaninas , Saccharomyces cerevisiae , Glutationa , Glutationa Peroxidase/genética , Lisossomos , Melaninas/metabolismo , Microrganismos Geneticamente Modificados , Saccharomyces cerevisiae/genética
10.
Biotechnol Appl Biochem ; 68(1): 173-184, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32198781

RESUMO

Human health is recently affected by several factors in which food contamination is one of the most dangerous elements that damage directly on our bodies. In this study, we provided a novel approach for the rapid detection of Salmonella sp. at the molecular level using the response of Saccharomyces cerevisiae's vacuoles. First, an augmentation of vacuoles intensity was observed by confocal microscopy after treating Salmonella strains with yeast cells. Second, the vacuolar enzymes were isolated and then analyzed by two-dimensional electrophoresis for the screening of specific biomarkers. After that, various recombinant yeasts containing exclusive biomarkers were constructed by fusing these biomarkers with several fluorescent proteins. Finally, the recombinant strains showed the ability to detect Salmonella strains specifically by appropriate fluorescent signals from 20 CFU/mL after 15 Min of exposure.


Assuntos
Técnicas de Tipagem Bacteriana , Bioensaio , Proteínas Fúngicas , Saccharomyces cerevisiae , Salmonella , Vacúolos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vacúolos/genética , Vacúolos/metabolismo , Vacúolos/microbiologia
11.
Mikrochim Acta ; 188(10): 333, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34498149

RESUMO

Nucleic acid amplification tests (NAATs) are powerful tools for the Japanese encephalitis virus (JEV). We demonstrated highly sensitive, specific, and rapid detection of JEV by colorimetric reverse-transcription loop-mediated isothermal amplification (cRT-LAMP). Under optimized conditions, the RT-LAMP assay results showed that the limit of detection was approximately equivalent to 1 RNA genome copy/µL with an assay time of 30 min. The assay was highly specific to JEV when tested with other mosquito-borne virus panels (Zika virus and dengue virus types 2-4). The ability to detect JEV directly from crude human sample matrices (serum and urine) demonstrated the suitability of our JEV RT-LAMP for widespread clinical application. The JEV RT-LAMP provides combination of  rapid colorimetric determination of true-positive JEV RT-LAMP amplicons with our recently developed JEV-nanobarcodes, measured at absorbance wavelenght of 530 (A530) and 650 (A650), which have a limit of detection of 23.3 ng/µL. The AuNP:polyA10-JEV RT-LAMP nanobarcodes exhibited superior capability for stabilizing the true-positive JEV RT-LAMP amplicons against salt-induced AuNP aggregation, which improved the evaluation of true/false positive signals in the assay. These advances enable to expand the use of RT-LAMP for point-of-care tests, which will greatly bolster JEV clinical programs. The JEV RT-LAMP nanobarcode assay targeting the envelope (E) gene and MgSO4 induced AuNP aggregation, indicated by an instant pink-to-violet colorimetric read-out.


Assuntos
Colorimetria/métodos , Vírus da Encefalite Japonesa (Espécie)/química , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/análise , Animais , Sequência de Bases , Sangue/virologia , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Limite de Detecção , Nanopartículas Metálicas/química , Poli A/química , RNA Viral/sangue , RNA Viral/urina , Suínos , Urina/virologia
12.
Anal Biochem ; 606: 113856, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32755600

RESUMO

Cell blocking (CB) technique has been widely applied in many studies since the last century. In our research, this technique was mostly used to study the enhancement of the vacuolar response-based system that could detect Shigella sp. and Salmonella sp. investigated in previous studies. The recombinant yeast cells were blocked by mixing with agarose gel on a 96-wells plate, then storing this plate in -80 °C before using. The optimal conditions for the new system, such as agarose concentration, maximum storage time, were also established. Finally, the efficiency of the vacuolar response-based system was improved, and this system could be used as a portable detector for the foodborne pathogen.


Assuntos
Fluorometria/métodos , Saccharomyces cerevisiae/metabolismo , Salmonella/isolamento & purificação , Shigella/isolamento & purificação , Corantes Fluorescentes/análise , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Salmonella/química , Shigella/química , Vacúolos/química , Vacúolos/microbiologia
13.
Ecotoxicology ; 29(7): 892-899, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32728873

RESUMO

Daphnia has been widely used as an indicator species in aquatic biomonitoring for decades. Traditional toxicity assays based on lethality take a long time to assess, and the effect mode of contaminants is not clear. Because of the translucency of the Daphnia body and the application of fluorescent probes in cell staining, different intoxicated parts can be visualized. In this study, a double-staining method using two fluorescent dyes, Calcein AM (cell-permeant dye) and Propidium Iodide (cell-impermeant dye), was carried out on Daphnia magna exposed to six pathogens: Salmonella spp. (four strains) and Shigella spp. (two strains). The results showed that those bacteria caused different infections on daphnia depending on the age of this organism and bacterial concentrations. In detail, S. dublin and S. sonnei are the most harmful to Daphnia when they cause damage at smaller concentrations at the younger stage (3 weeks old). Interestingly, older Daphnia can give responses to nearly 10 CFU/ml to less than 100 CFU/ml of some bacteria strains. In another experiment, S. sonnei disturbed Daphnia after just 10 min of exposure, and Daphnia adapted to S. choleraesuis, S. typhi, and S. flexneri at the early stage (3 weeks old) after 1 h of exposure. Moreover, the damaged areas of the daphnia body were directly observed via a microscope, contributing to the understanding and the prediction of toxicity mechanisms.


Assuntos
Daphnia/microbiologia , Salmonella/química , Shigella/química , Testes de Toxicidade/métodos , Animais , Corantes Fluorescentes/análise , Coloração e Rotulagem
14.
J Basic Microbiol ; 60(4): 341-350, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32043631

RESUMO

Vacuoles are useful materials with antimicrobial and anticancerous properties. Vacuolar proteins can discompose macromolecules from the outside of yeast cells. The objective of this study was to determine the function of a protein transported into a vacuole. Specifically, cytosolic protein aldehyde dehydrogenase 6 (ALD6) was used for the delivery to the vacuole. To transport cytosolic protein to the vacuole in this study, a transfer vector including a signal peptide sequence isolated from vacuolar protein proteinase A was designed. A signal peptide is an amino acid sequence in front of the transported protein. Signal peptides have various delivery pathways according to the kind of signal sequence they contain. They play important roles in transporting proteins to organelles, in cellular mechanisms, and the transfer of protein outside and inside eukaryotes. Thus, we focused on the design of a transfer vector containing a signal peptide sequence isolated from the DNA sequence of proteinase A (PEP4). In addition, this study evaluated the expression level of cytosolic ALD6 after being transported into the yeast vacuole. Our results showed that the developed transfer vector was useful for delivering proteins to vacuole by using signal peptide sequence. Therefore, this transfer vector might be used as a tool to deliver target proteins to organelles of interest in eukaryotes.


Assuntos
Aldeído Oxirredutases/metabolismo , Ácido Aspártico Endopeptidases/genética , Citosol/metabolismo , Sinais Direcionadores de Proteínas , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimologia , Vacúolos/metabolismo , Aldeído Oxirredutases/genética , Transporte Proteico
15.
Int J Mol Sci ; 20(16)2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31430857

RESUMO

Osteoporosis is a common disorder of bone remodeling, caused by the imbalance between bone resorption by osteoclasts and bone formation by osteoblasts. Recently, we reported that matrix metalloproteinase-9 (MMP-9)-dependent histone H3 proteolysis is a key event for proficient osteoclast formation. Although it has been reported that several MMP-9 inhibitors, such as tetracycline and its derivatives, show an inhibitory effect on osteoclastogenesis, the molecular mechanisms for this are not fully understood. Here we show that tetracycline analogs, especially tigecycline and minocycline, inhibit osteoclast formation by blocking MMP-9-mediated histone H3 tail cleavage. Our molecular docking approach found that tigecycline and minocycline are the most potent inhibitors of MMP-9. We also observed that both inhibitors significantly inhibited H3 tail cleavage by MMP-9 in vitro. These compounds inhibited receptor activator of nuclear factor kappaB ligand (RANKL)-induced osteoclast formation by blocking the NFATc1 signaling pathway. Furthermore, MMP-9-mediated H3 tail cleavage during osteoclast differentiation was selectively blocked by these compounds. Treatment with both tigecycline and minocycline rescued the osteoporotic phenotype induced by prednisolone in a zebrafish osteoporosis model. Our findings demonstrate that the tetracycline analogs suppress osteoclastogenesis via MMP-9-mediated H3 tail cleavage, and suggest that MMP-9 inhibition could offer a new strategy for the treatment of glucocorticoid-induced osteoporosis.


Assuntos
Histonas/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Minociclina/farmacologia , Osteogênese/efeitos dos fármacos , Tigeciclina/farmacologia , Animais , Células Cultivadas , Feminino , Humanos , Masculino , Modelos Moleculares , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Peixe-Zebra
16.
Int J Syst Evol Microbiol ; 68(7): 2258-2264, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29809120

RESUMO

Strain GI5T was isolated from a surface seawater sample collected from Garorim Bay (West Sea, Republic of Korea). The isolated strain was aerobic, Gram-stain-negative, rod-shaped, motile by means of a polar flagellum, negative for catalase and weakly positive for oxidase. The optimum growth pH, salinity and temperature were determined to be pH 7.5-8.0, 3 % NaCl (w/v) and 25 °C, respectively; the growth ranges were pH 6.0-9.0, 1-7 % NaCl (w/v) and 18-40 °C. The results of phylogenetic analysis of 16S rRNA gene sequences indicated that GI5T clustered within the family Alcanivoracaceae, and most closely with Alcanivorax dieseloleiB-5T and Alcanivorax marinusR8-12T (91.9 % and 91.6 % similarity, respectively). The major cellular fatty acids in GI5T were C18 : 1ω7c/C18 : 1ω6c (44.45 %), C16 : 1ω6c/C16 : 1ω7c (14.17 %) and C16 : 0 (10.19 %); this profile was distinct from those of the closely related species. The major respiratory quinone of GI5T was Q-8. The main polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Two putative alkane hydroxylase (alkB) genes were identified in GI5T. The G+C content of the genomic DNA of GI5T was determined to be 51.2 mol%. On the basis of the results of phenotypic, chemotaxonomic and phylogenetic studies, strain GI5T represents a novel species of a novel genus of the family Alcanivoracaceae, for which we propose the name Ketobacter alkanivorans gen. nov., sp. nov.; the type strain is GI5T (=KCTC 52659T=JCM 31835T).


Assuntos
Alcanivoraceae/classificação , Alcanos/metabolismo , Filogenia , Água do Mar/microbiologia , Alcanivoraceae/genética , Alcanivoraceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
17.
J Nanosci Nanotechnol ; 18(6): 3936-3943, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442729

RESUMO

Sphingobium chungbukense DJ77 is a Gram-negative bacterium has metabolic capability of producing exopolysaccharide (EPS) as a potential reducing and stabilizing agent for metallic nanoparticle synthesis. In this study, we investigated the genomic and proteomic analysis to verify metabolic pathway and involved genes and enzymes related to EPS biosynthesis in S. chungbukense DJ77. End-sequencing results of randomly selected fosmid library, which were prepared from high molecular weight DNA of S. chungbukense DJ77, showed identity to sequences from genes related the EPS biosynthesis pathways in several bacteria. We also observed that proteomic responses in S. chungbukense DJ77 by heterogeneously expressing gelA and gelN involved in gellan biosynthesis in Sphingomonas elodea. Comparative two-dimensional gel electrophoresis revealed that both GelA and GelN altered internal expression levels of proteins involved in EPS biosynthesis in S. chungbukense DJ77. The results might provide the genomic and proteomic evidences for presence of EPS biosynthesis pathways in S. chungbukense DJ77.


Assuntos
Polissacarídeos/metabolismo , Proteômica , Sphingomonadaceae/metabolismo , Polissacarídeos Bacterianos , Sphingomonas
18.
J Nanosci Nanotechnol ; 18(4): 2979-2985, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442983

RESUMO

Formaldehyde is a toxic compound due to its ability to react with proteins, nucleic acids and lipids and is the primary cause of nasopharyngeal cancer and sick building syndrome (SBS). Aldehyde dehydrogenases (ALDHs) are able to oxidize aldehyde substrates and maintain cellular homeostasis by metabolic reactions in prokaryotic and eukaryotic cells. ALDHs catalyze the conversions of various aldehydes to carboxylic acids using NAD or NADP as a cofactor. In this study, we designed a method for using aldehyde dehydrogenase 6 (ALD6) from recombinant Saccharomyces cerevisiae to reduce formaldehyde. The ALD6 gene was cloned under the GAL1 promoter in pYES2 and attached to green fluorescent protein (GFP). To reduce the activity of ALD6, a dominant mutant was constructed with deleted catalytic residues. These strains were successfully transformed in Saccharomyces cerevisiae as confirmed by fluorescence microscopy. The produced enzymes isolated from each strain were used to treat formaldehyde. Formaldehyde reduction was determined via measured luminescence in Vibrio fischeri. Formaldehyde levels were lowest in enzymes from cells overexpressing ALD6. Furthermore, when the strains were exposed to formaldehyde stress, NADH levels increased for strains overexpressing ALD6 and decreased for dominant negative strains. Therefore, our results suggest that ALD6 plays a key role in formaldehyde treatment. We expect that ALD6 could be used in applications related to the removal of formaldehyde.


Assuntos
Aldeído Oxirredutases/metabolismo , Formaldeído/química , Saccharomyces cerevisiae/enzimologia , Aldeído Desidrogenase , Expressão Gênica , Oxirredução
19.
J Nanosci Nanotechnol ; 18(5): 3095-3101, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442808

RESUMO

Shigella sonnei isolate invasion plasmid antigen protein, IpaH, was successfully expressed in recombinant overexpression bacterial system. The soluble expression IpaH was enhanced with molecular chaperon co-expressed environment. Specific aptamer IpaH17 was isolated through the SELEX process and showed fM binding affinity. IpaH17-SPR biosensor platform was involved to verify the binding sensitivity and specificity. The IpaH concentration dependent IpaH17-SPR sensor response was highly linear with a linear regression constant of 99.4% in the range between 0 and 100 ng/mL. In addition, S. sonnei revealed the specific RU value and detected in a real-time manner within 1 hour. Our study indicated that IpaH17-SPR sensor can allow for rapid, sensitive and specific determination of Shigella sonnei virulent factor.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Shigella sonnei/patogenicidade , Ressonância de Plasmônio de Superfície , Sensibilidade e Especificidade , Virulência
20.
J Nanosci Nanotechnol ; 18(3): 1599-1605, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448635

RESUMO

In this paper, whole-bacteria SELEX (WB-SELEX) strategy was adopted to isolate specific aptamers against Vibrio parahaemolyticus. Round selection for V. parahaemolyticus was conducted 11 rounds, including two negative selection rounds. It was determined through real-time PCR amplification and post-SELEX experiment. The selected aptmers had high binding property and specificity to V. parahaemolyticus. Of 28 aptamers tested, VPCA-apta#1 had the highest binding affinity compared to other aptamer candidates obtained. To detect V. parahaemolyticus, aptamer based SPR biosensor platform was constructed and pathogenic bacteria sensing was conducted in two steps. The first step was to construct 5'-biotinylated VPCA-apta#1 binding probe. The second step was to incubate V. parahaemolyticus and test microbes in functionalized SA sensor chip in parallel. Our platform showed significant activity for detecting and discriminating V. parahaemolyticus from other enteric species such as Escherichia coli, Listeria monocytogenes, Sigella sonnei, and Vibrio fischeri. This is the first report on the use of whole-SELEX to isolate DNA aptamers specific for V. parahaemolyticus. We demonstrated the feasibility of using aptamer platform for the detection of V. parahaemolyticus in various food supplies. It might be used in multiple points of care for diagnosing Vibriosis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnica de Seleção de Aptâmeros , Ressonância de Plasmônio de Superfície , Vibrio parahaemolyticus , Reação em Cadeia da Polimerase
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