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1.
Talanta ; 258: 124455, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36933297

RESUMO

A genetic approach targeted toward improving athletic performance is called gene doping and is prohibited by the World Anti-Doping Agency. Currently, the clustered regularly interspaced short palindromic repeats-associated protein (Cas)-related assays have been utilized to detect genetic deficiencies or mutations. Among the Cas proteins, deadCas9 (dCas9), a nuclease-deficient mutant of Cas9, acts as a DNA binding protein with a target-specific single guide RNA. On the basis of the principles, we developed a dCas9-based high-throughput gene doping analysis for exogenous gene detection. The assay comprises two distinctive dCas9s, a magnetic bead immobilized capture dCas9 for exogenous gene isolation and a biotinylated dCas9 with streptavidin-polyHRP that enables rapid signal amplification. For efficient biotin labeling via maleimide-thiol chemistry, two cysteine residues of dCas9 were structurally validated, and the Cys574 residue was identified as an essential labeling site. As a result, we succeeded in detecting the target gene in a concentration as low as 12.3 fM (7.41 × 105 copies) and up to 10 nM (6.07 × 1011 copies) in a whole blood sample within 1 h with HiGDA. Assuming an exogenous gene transfer scenario, we added a direct blood amplification step to establish a rapid analytical procedure while detecting target genes with high sensitivity. Finally, we detected the exogenous human erythropoietin gene at concentrations as low as 2.5 copies within 90 min in 5 µL of the blood sample. Herein, we propose that HiGDA is a very fast, highly sensitive, and practical detection method for actual doping field in the future.


Assuntos
Sistemas CRISPR-Cas , Eritropoetina , Humanos , Eritropoetina/genética
2.
Biotechnol Lett ; 45(5-6): 589-600, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36971774

RESUMO

OBJECTIVES: S100A8 is highly expressed in several inflammatory and oncological conditions. To address the current lack of a reliable and sensitive detection method for S100A8, we generated a monoclonal antibody with a high binding affinity to human S100A8 to enable early disease diagnosis. RESULTS: A soluble recombinant S100A8 protein with a high yield and purity was produced using Escherichia coli. Next, mice were immunized with recombinant S100A8 to obtain anti-human S100A8 monoclonal antibodies using hybridoma technology. Lastly, the high binding activity of the antibody was confirmed and its sequence was identified. CONCLUSIONS: This method, including the production of antigens and antibodies, will be useful for the generation of hybridoma cell lines that produce anti-S100A8 monoclonal antibodies. Moreover, the sequence information of the antibody can be used to develop a recombinant antibody for use in various research and clinical applications.


Assuntos
Anticorpos Monoclonais , Calgranulina A , Animais , Camundongos , Anticorpos Monoclonais/química , Hibridomas , Linhagem Celular , Proteínas Recombinantes/genética , Biomarcadores
3.
Curr Opin Biotechnol ; 80: 102914, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36857963

RESUMO

Polyphenols are bioactive molecules that are used in therapeutics. Polyphenol hydroxylation and glycosylation have been shown to increase their bioavailability, solubility, bioactivity, and stability for use in various applications. Ortho-hydroxylation of polyphenols using tyrosinase allows high selectivity and yield without requiring a cofactor, while meta- and para-hydroxylation of polyphenols are mediated by site-specific hydroxylases and cytochrome P450s, although these processes are somewhat rare. O-glycosylation of polyphenols proceeds further after hydroxylation. The O-glycosylation reaction typically requires nucleotide diphosphate (NDP) sugar. However, amylosucrase (AS) has emerged as a promising enzyme for polyphenol glycosylation in large-scale production without requiring NDP-sugar. Overall, this review describes recent findings on the enzymatic mechanisms, enzyme engineering, and applications of enzymatic reactions.


Assuntos
Sistema Enzimático do Citocromo P-450 , Polifenóis , Glicosilação , Hidroxilação , Carboidratos , Açúcares
4.
Biochem Pharmacol ; 209: 115415, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36657604

RESUMO

Chronic solar ultraviolet exposure is a major risk factor for cutaneous squamous cell carcinoma (cSCC), which is the second most common type of skin cancer. Our previous data showed that total protein and phosphorylation levels of T-LAK cell-originated protein kinase (TOPK) were enhanced in solar-simulated light (SSL)-induced skin carcinogenesis and overexpressed in actinic keratosis (AK) and cSCC human skin tissues compared to those in matched normal skin. Thus, targeting TOPK activity could be a helpful approach for treating cSCC. Our data showed that orobol directly binds to TOPK in an ATP-independent manner and inhibits TOPK kinase activity. Furthermore, orobol inhibited anchorage-independent colony formation by SCC12 cells in a dose-dependent manner. After discontinuing the treatment, patients commonly return to tumor-bearing conditions; therefore, therapy or intermittent dosing of drugs must be continued indefinitely. Thus, to examine the efficacy of orobol against the development and regrowth of cSCC, we established mouse models including prevention, and therapeutic models on the chronic SSL-irradiated SKH-1 hairless mice. Early treatment with orobol attenuates chronic SSL-induced cSCC development. Furthermore, orobol showed therapeutic efficacy after the formation of chronic SSL irradiation-induced tumor. In the mouse model with intermittent dosing of orobol, our data showed that re-application of orobol is effective for reducing tumor regrowth after discontinuation of treatment. Moreover, oncogenic protein levels were significantly attenuated by orobol treatment in the SSL-stimulated human skin. Thus, we suggest that orobol, as a promising TOPK inhibitor, could have an effective clinical approach to prevent and treat the development and regrowth of cSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Animais , Camundongos , Neoplasias Cutâneas/tratamento farmacológico , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/patologia , Raios Ultravioleta/efeitos adversos , Modelos Animais de Doenças
5.
Chem Commun (Camb) ; 59(1): 94-97, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36472163

RESUMO

Bridging biological tissues for immediate adhesion and long-term sustainability was accomplished using a combination of mesoporous silica nanoparticles (MSNs) and tyrosinase. Tyrosinase-loaded MSNs provided rapid physical adsorption, while tyrosinase within MSNs induced enzymatic chemical bond gluing of tissues. This synergistic strategy has robust potential in tissue adhesives for clinical settings.


Assuntos
Monofenol Mono-Oxigenase , Nanopartículas , Humanos , Dióxido de Silício/química , Aderências Teciduais , Nanopartículas/química , Adesivos , Porosidade
6.
Biochem Biophys Res Commun ; 636(Pt 1): 184-189, 2022 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-36334443

RESUMO

Matrix metalloproteinase 9 (MMP9) contributes to several aspects of inflammation and cancer pathology, including invasion, metastasis, and angiogenesis. In this study, we expressed a recombinant fragment antigen-binding (Fab)-type anti-MMP9 antibody in Escherichia coli with high purity within five days and confirmed the nanomolar order of antigen-binding efficiency of the recombinant Fab. Moreover, we optimized the experimental time for performing enzyme-linked immunosorbent assay (ELISA), and decreased the reaction time from the conventional 20.5 h to 3.5 h. The rapid and sensitive MMP9 detection system developed in this study can be applied to a range of applications, including the diagnosis of diseases with MMP9 overexpression including inflammatory and cancer-related diseases.


Assuntos
Escherichia coli , Fragmentos Fab das Imunoglobulinas , Fragmentos Fab das Imunoglobulinas/genética , Proteínas Recombinantes , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Metaloproteases
7.
Biotechnol Bioeng ; 119(10): 2938-2949, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35876239

RESUMO

6-Bromoindirubin (6BrIR), found in Murex sea snails, is a precursor of indirubin-derivatives anticancer drugs. However, its synthesis remains limited due to uncharacterized biosynthetic pathways and difficulties in site-specific bromination and oxidation at the indole ring. Here, we present an efficient 6BrIR production strategy in Escherichia coli by using four enzymes, that is, tryptophan 6-halogenase fused with flavin reductase Fre (Fre-L3-SttH), tryptophanase (TnaA), toluene 4-monooxygenase (PmT4MO), and flavin-containing monooxygenase (MaFMO). Although most indole oxygenases preferentially oxygenate the electronically active C3 position of indole, PmT4MO was newly characterized to perform C2 oxygenation of 6-bromoindole with 45% yield to produce 6-bromo-2-oxindole. In addition, 6BrIR was selectively generated without indigo and indirubin byproducts by controlling the reducing power of cysteine and oxygen supply during the MaFMO reaction. These approaches led to 34.1 mg/L 6BrIR productions, making it possible to produce the critical precursor of the anticancer drugs only from natural ingredients such as tryptophan, NaBr, and oxygen.


Assuntos
Escherichia coli , Triptofano , Escherichia coli/metabolismo , Indóis , Oxigênio/metabolismo , Triptofano/metabolismo
8.
Nat Commun ; 13(1): 2540, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534484

RESUMO

Epitranscriptomic features, such as single-base RNA editing, are sources of transcript diversity in cancer, but little is understood in terms of their spatial context in the tumour microenvironment. Here, we introduce spatial-histopathological examination-linked epitranscriptomics converged to transcriptomics with sequencing (Select-seq), which isolates regions of interest from immunofluorescence-stained tissue and obtains transcriptomic and epitranscriptomic data. With Select-seq, we analyse the cancer stem cell-like microniches in relation to the tumour microenvironment of triple-negative breast cancer patients. We identify alternative splice variants, perform complementarity-determining region analysis of infiltrating T cells and B cells, and assess adenosine-to-inosine base editing in tumour tissue sections. Especially, in triple-negative breast cancer microniches, adenosine-to-inosine editome specific to different microniche groups is identified.


Assuntos
Adenosina Desaminase , Neoplasias de Mama Triplo Negativas , Adenosina/genética , Adenosina Desaminase/genética , Humanos , Inosina/genética , Células-Tronco Neoplásicas , Microambiente Tumoral/genética
9.
Front Bioeng Biotechnol ; 10: 830712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402392

RESUMO

Several regiospecific enantiomers of hydroxy-(S)-equol (HE) were enzymatically synthesized from daidzein and genistein using consecutive reduction (four daidzein-to-equol-converting reductases) and oxidation (4-hydroxyphenylacetate 3-monooxygenase, HpaBC). Despite the natural occurrence of several HEs, most of them had not been studied owing to the lack of their preparation methods. Herein, the one-pot synthesis pathway of 6-hydroxyequol (6HE) was developed using HpaBC (EcHpaB) from Escherichia coli and (S)-equol-producing E. coli, previously developed by our group. Based on docking analysis of the substrate or products, a potential active site and several key residues for substrate binding were predicted to interpret the (S)-equol hydroxylation regioselectivity of EcHpaB. Through investigating mutations on the key residues, the T292A variant was verified to display specific mono-ortho-hydroxylation activity at C6 without further 3'-hydroxylation. In the consecutive oxidoreductive bioconversion using T292A, 0.95 mM 6HE could be synthesized from 1 mM daidzein, while 5HE and 3'HE were also prepared from genistein and 3'-hydroxydaidzein (3'HD or 3'-ODI), respectively. In the following efficacy tests, 3'HE and 6HE showed about 30∼200-fold higher EC50 than (S)-equol in both ERα and ERß, and they did not have significant SERM efficacy except 6HE showing 10% lower ß/α ratio response than that of 17ß-estradiol. In DPPH radical scavenging assay, 3'HE showed the highest antioxidative activity among the examined isoflavone derivatives: more than 40% higher than the well-known 3'HD. In conclusion, we demonstrated that HEs could be produced efficiently and regioselectively through the one-pot bioconversion platform and evaluated estrogenic and antioxidative activities of each HE regio-isomer for the first time.

10.
BMC Biotechnol ; 22(1): 8, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35255869

RESUMO

BACKGROUND: Human matrix metalloproteinase 9 (hMMP9) is a biomarker in several diseases, including cancer, and the need for developing detectors and inhibitors of hMMP9 is increasing. As an antibody against hMMP9 can be selectively bound to hMMP9, the use of anti-MMP9 antibody presents new possibilities to address hMMP9-related diseases. In this study, we aimed to establish a stable Chinese hamster ovary (CHO) cell line for the stable production of antibodies against hMMP9. RESULTS: Weconstructed recombinant anti-hMMP9 antibody fragment-expressing genes and transfected these to CHO cells. We chose a single clone, and successfully produced a full-sized antibody against hMMP9 with high purity, sensitivity, and reproducibility. Subsequently, we confirmed the antigen-binding efficiency of the antibody. CONCLUSIONS: We developed a novel recombinant anti-hMMP9 antibody via a CHO cell-based mammalian expression system, which has a high potential to be used in a broad range of medical and industrial areas.


Assuntos
Metaloproteinase 9 da Matriz , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Metaloproteinase 9 da Matriz/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reprodutibilidade dos Testes
11.
Microorganisms ; 9(9)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34576760

RESUMO

Tyrosinase is generally known as a melanin-forming enzyme, facilitating monooxygenation of phenols, oxidation of catechols into quinones, and finally generating biological melanin. As a homologous form of tyrosinase in plants, plant polyphenol oxidases perform the same oxidation reactions specifically toward plant polyphenols. Recent studies reported synthetic strategies for large scale preparation of hydroxylated plant polyphenols, using bacterial tyrosinases rather than plant polyphenol oxidase or other monooxygenases, by leveraging its robust monophenolase activity and broad substrate specificity. Herein, we report a novel synthesis of functional plant polyphenols, especially quercetin and myricetin from kaempferol, using screened bacterial tyrosinases. The critical bottleneck of the biocatalysis was identified as instability of the catechol and gallol under neutral and basic conditions. To overcome such instability of the products, the tyrosinase reaction proceeded under acidic conditions. Under mild acidic conditions supplemented with reducing agents, a bacterial tyrosinase from Bacillus megaterium (BmTy) displayed efficient consecutive two-step monophenolase activities producing quercetin and myricetin from kaempferol. Furthermore, the broad substrate specificity of BmTy toward diverse polyphenols enabled us to achieve the first biosynthesis of tricetin and 3'-hydroxyeriodictyol from apigenin and naringenin, respectively. These results suggest that microbial tyrosinase is a useful biocatalyst to prepare plant polyphenolic catechols and gallols with high productivity, which were hardly achieved by using other monooxygenases such as cytochrome P450s.

12.
Biotechnol Bioeng ; 118(4): 1612-1623, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421096

RESUMO

The commensal gut bacterium Akkermansia muciniphila is well known as a promising probiotic candidate that improves host health and prevents diseases. However, the biological interaction of A. muciniphila with human gut epithelial cells has rarely been explored for use in biotherapeutics. Here, we developed an in vitro device that simulates the gut epithelium to elucidate the biological effects of living A. muciniphila via multiomics analysis: the Mimetic Intestinal Host-Microbe Interaction Coculture System (MIMICS). We demonstrated that both human intestinal epithelial cells (Caco-2) and the anaerobic bacterium A. muciniphila can remain viable for 12 h after coculture in the MIMICS. The transcriptomic and proteomic changes (cell-cell junctions, immune responses, and mucin secretion) in gut epithelial cells treated with A. muciniphila closely correspond with those reported in previous in vivo studies. In addition, our proteomic and metabolomic results revealed that A. muciniphila activates glucose and lipid metabolism in gut epithelial cells, leading to an increase in ATP production. This study suggests that A. muciniphila improves metabolism for ATP production in gut epithelial cells and that the MIMICS may be an effective general tool for evaluating the effects of anaerobic bacteria on gut epithelial cells.


Assuntos
Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Akkermansia/crescimento & desenvolvimento , Células CACO-2 , Técnicas de Cocultura , Humanos
13.
Biomaterials ; 242: 119905, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32145505

RESUMO

Epigallocatechin gallates (EGCGs), isolated from green tea, have intrinsic properties such as anti-oxidant, anti-inflammation, and radical scavenger effects. In this study, we report a tissue adhesive and anti-inflammatory hydrogel formed by high-affinity enzymatic crosslinking of polyphenolic EGCGs. A mixture of EGCG conjugated hyaluronic acids (HA_E) and tyramine conjugated hyaluronic acids (HA_T) was reacted with tyrosinase isolated from Streptomyces avermitillis (SA_Ty) to form that displayed fast enzyme kinetic to form a crosslinked adhesive hydrogel. A 1,2,3-trihydroxyphenyl group in EGCG displayed a high affinity to SA_Ty that allowed HA_E to be quickly oxidized and crosslinked with HA_T to form HA_T and HA_E mixed hydrogel (HA_TE). We then compared the HA_TE hydrogel with commercially available tissue adhesives, such as cyanoacrylate and fibrin glue. We report that the HA_TE exhibited the highest tissue adhesiveness both in wet and dry conditions. Furthermore, HA_TE successfully closed a skin wound and displayed insignificant host tissue responses. This demonstrates that polyphenol-incorporated anti-inflammatory hydrogel may provide a robust tissue adhesive platform for clinical applications.

14.
Theranostics ; 9(15): 4255-4264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285760

RESUMO

The ability of brain tissue to regenerate is limited; therefore, brain diseases (i.e., trauma, stroke, tumors) often lead to irreversible motor and cognitive impairments. Therapeutic interventions using various types of injectable biomaterials have been investigated to promote endogenous neural differentiation. Despite promising results in pre-clinical studies, the translation of regenerative medicine to the clinic has many challenges due to the lack of reliable imaging systems to achieve accurate evaluation of the treatment efficacy. Methods: In this study, we developed a dual-channel fluorescence imaging technique to simultaneously monitor tissue ingrowth and scaffold disintegration. Enzymatically crosslinked gelatin-hyaluronic acid hydrogel was labeled with 800 nm fluorophore, ZW800-3a, while the regenerated tissue was highlighted with 700 nm brain-specific contrast agent, Ox1. Results: Using the multichannel fluorescence imaging system, tissue growth and degradation of the NIR hydrogel were simultaneously imaged in the brain of mice. Images were further analyzed and reconstructed to show both visual and quantitative information of each stage of a therapeutic period. Conclusion: Dual-channel in vivo imaging systems can provide highly accurate visual and quantitative information of the brain tissue ingrowth for the evaluation of the therapeutic effect of NIR hydrogel through a simple and fast operating procedure.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem Óptica/métodos , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Fluorescência , Gelatina/química , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/química , Hidrogéis/química , Camundongos , Camundongos Endogâmicos C57BL , Imagem Óptica/instrumentação , Regeneração , Alicerces Teciduais
15.
Biotechnol Bioeng ; 116(1): 19-27, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30011063

RESUMO

Tyrosinase is a type 3 copper oxygenase that catalyzes a phenol moiety into ortho-diphenol, and subsequently to ortho-quinone. Diverse tyrosinases have been observed across the kingdom including Animalia, Bacteria, Plantae, and Fungi. Among the tyrosinases, bacterial, and mushroom tyrosinases have been extensively exploited to prepare melanin, ortho-hydroxy-polyphenols, or novel plant secondary metabolites during the past decade. And their use as a biocatalyst to prepare various functional biocompounds have drawn great attention worldwide. Herein, we tailored a bacterial tyrosinase from Bacillus megaterium (BmTy) using circular permutation (CP) engineering technique which is a novel enzyme engineering technique to covalently link original N and C termini and create new termini on the middle of its polypeptide. To construct a smart rationally-designed CP library, we introduced 18 new termini at the edge of each nine loops that link α-helical secondary structure in BmTy. Among the small library, seven functional CP variants were successfully identified and they represented dramatic change in their enzyme characteristics including kinetic properties and substrate specificity. Especially, cp48, 102, and 245 showed dramatically decreased tyrosine hydroxylase activity, behaving like a catechol oxidase. Exploiting the dramatic increased polyphenol oxidation activity of cp48, orobol (3'-hydroxy-genistein) was quantitatively synthesized with 1.48 g/L, which was a 6-fold higher yield of truncated wild-type. We examined their kinetic characters through structural speculation, and suggest a strategy to solubilize the insoluble artificial variants effectively.


Assuntos
Bacillus megaterium/enzimologia , Flavonoides/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Proteínas Mutantes/metabolismo , Polifenóis/metabolismo , Engenharia de Proteínas/métodos , Cinética , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/genética , Proteínas Mutantes/química , Proteínas Mutantes/genética , Oxirredução , Conformação Proteica
16.
Sci Rep ; 8(1): 11088, 2018 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-30038332

RESUMO

Although several biomarkers can be used to distinguish cholangiocarcinoma (CCA) from healthy controls, differentiating the disease from benign biliary disease (BBD) or pancreatic cancer (PC) is a challenge. CCA biomarkers are associated with low specificity or have not been validated in relation to the biological effects of CCA. In this study, we quantitatively analyzed 15 biliary bile acids in CCA (n = 30), BBD (n = 57) and PC (n = 17) patients and discovered glycocholic acid (GCA) and taurochenodeoxycholic acid (TCDCA) as specific CCA biomarkers. Firstly, we showed that the average concentration of total biliary bile acids in CCA patients was quantitatively less than in other patient groups. In addition, the average composition ratio of primary bile acids and conjugated bile acids in CCA patients was the highest in all patient groups. The average composition ratio of GCA (35.6%) in CCA patients was significantly higher than in other patient groups. Conversely, the average composition ratio of TCDCA (13.8%) in CCA patients was significantly lower in all patient groups. To verify the biological effects of GCA and TCDCA, we analyzed the gene expression of bile acid receptors associated with the development of CCA in a CCA cell line. The gene expression of transmembrane G protein coupled receptor (TGR5) and sphingosine 1-phosphate receptor 2 (S1PR2) in CCA cells treated with GCA was 8.6-fold and 3.4-fold higher compared with control (untreated with bile acids), respectively. Gene expression of TGR5 and S1PR2 in TCDCA-treated cells was not significantly different from the control. Taken together, our study identified GCA and TCDCA as phenotype-specific biomarkers for CCA.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Biomarcadores Tumorais/metabolismo , Colangiocarcinoma/metabolismo , Ácido Glicocólico/metabolismo , Ácido Tauroquenodesoxicólico/metabolismo , Neoplasias dos Ductos Biliares/genética , Linhagem Celular Tumoral , Colangiocarcinoma/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Fenótipo
17.
Appl Microbiol Biotechnol ; 102(16): 6915-6921, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948112

RESUMO

A potent phytoestrogen, (S)-equol, is a promising isoflavone derivative drawing our great attention owing to its various biological and clinical benefits. Through selective activation of the estrogen receptor ERß or androgen receptor, (S)-equol reduces menopausal symptoms, osteoporosis, skin aging, hair loss, and incidence of prostate or ovarian cancers without adverse effects. Traditional biosynthesis of (S)-equol exploited non-productive natural equol-producing anaerobic bacteria that mainly belong to Coriobacteriaceae isolated from human intestine. Recently, we developed a recombinant Escherichia coli strain which could convert daidzein into (S)-equol effectively under an aerobic condition. However, the yield was limited up to about the 200 mg/L level due to unknown reasons. In this study, we identified that the bottleneck of the limited production was the low solubility of isoflavone (i.e., 2.4 mg/L) in the reaction medium. In order to solve the solubility problem without harmful effect to the whole-cell catalyst, we applied commercial hydrophilic polymers (HPs) and a polar aprotic co-solvent in the reaction medium. Among the examined water-soluble polymers, polyvinylpyrrolidone (PVP)-40k was verified as the most promising supplement which increased daidzein solubility by 40 times and (S)-equol yield up to 1.22 g/L, the highest ever reported and the first g/L level biotransformation. Furthermore, PVP-40k was verified to significantly increase the solubilities of other water-insoluble natural polyphenols in aqueous solution. We suggest that addition of both HP and polar aprotic solvent in the reaction mixture is a powerful alternative to enhance production of polyphenolic chemicals rather than screening appropriate organic solvents for whole-cell catalysis of polyphenols.


Assuntos
Equol/biossíntese , Microbiologia Industrial/métodos , Solventes/química , Escherichia coli/genética , Isoflavonas/química , Água/química
18.
Anal Biochem ; 550: 27-33, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29649473

RESUMO

Ribozyme (Rz) is a very attractive RNA molecule in metabolic engineering and synthetic biology fields where RNA processing is required as a control unit or ON/OFF signal for its cleavage reaction. In order to use Rz for such RNA processing, Rz must have highly active and specific catalytic activity. However, current methods for assessing the intracellular activity of Rz have limitations such as difficulty in handling and inaccuracies in the evaluation of correct cleavage activity. In this paper, we proposed a simple method to accurately measure the "intracellular cleavage efficiency" of Rz. This method deactivates unwanted activity of Rz which may consistently occur after cell lysis using DNA quenching method, and calculates the cleavage efficiency by analyzing the cleaved fraction of mRNA by Rz from the total amount of mRNA containing Rz via quantitative real-time PCR (qPCR). The proposed method was applied to measure "intracellular cleavage efficiency" of sTRSV, a representative Rz, and its mutant, and their intracellular cleavage efficiencies were calculated as 89% and 93%, respectively.


Assuntos
Nepovirus/enzimologia , RNA Catalítico/química , RNA Mensageiro/química , RNA Viral/química , Reação em Cadeia da Polimerase em Tempo Real/métodos
19.
Biomacromolecules ; 19(5): 1602-1613, 2018 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-29589900

RESUMO

Prevention of biofouling and microbial contamination of implanted biomedical devices is essential to maintain their functionality and biocompatibility. For this purpose, polypept(o)ide block copolymers have been developed, in which a protein-resistant polysarcosine (pSar) block is combined with a dopamine-modified poly(glutamic acid) block for surface coating and silver nanoparticles (Ag NPs) formation. In the development of a novel, versatile, and biocompatible antibacterial surface coating, block lengths pSar were varied to derive structure-property relationships. Notably, the catechol moiety performs two important tasks in parallel; primarily it acts as an efficient anchoring group to metal oxide surfaces, while it furthermore induces the formation of Ag NPs. Attributing to the dual function of catechol moieties, antifouling pSar brush and antimicrobial Ag NPs can not only adhere stably on metal oxide surfaces, but also display passive antifouling and active antimicrobial activity, showing good biocompatibility simultaneously. The developed strategy seems to provide a promising platform for functional modification of biomaterials surface to preserve their performance while reducing the risk of bacterial infections.


Assuntos
Anti-Infecciosos/química , Catecóis/química , Dopamina/análogos & derivados , Nanopartículas/química , Ácido Poliglutâmico/análogos & derivados , Óxidos/química , Prata/química
20.
J Biotechnol ; 267: 50-54, 2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29307836

RESUMO

Streptomyces peucetius ATCC 27952 is a filamentous soil bacterium with potential to produce anthracyclines such as doxorubicin (DXR) and daunorubicin (DNR), which are potent chemotherapeutic agents for the treatment of cancer. Here we present the complete genome sequence of S. peucetius ATCC 27952, which consists of 8,023,114 bp with a linear chromosome, 7187 protein-coding genes, 18 rRNA operons and 66 tRNAs. Bioinformatic analysis of the genome sequence revealed ∼68 putative gene clusters involved in the biosynthesis of secondary metabolites, including diverse classes of natural products. Diverse secondary metabolites of PKS (polyketide synthase) type II (doxorubicin and daunorubicin), NRPS (non-ribosomal peptide synthase) (T1-pks), terpene (hopene) etc. have already been reported for this strain. In addition, in silico analysis suggests the potential to produce diverse compound classes such as lantipeptides, lassopeptides, NRPS and polyketides. Furthermore, many catalytically-efficient enzymes involved in hydroxylation, methylation etc. have been characterized in this strain. The availability of genomic information provides valuable insight for devising rational strategies for the production and isolation of diverse bioactive compounds as well as for the industrial application of efficient enzymes.


Assuntos
Antraciclinas/metabolismo , Genoma Bacteriano/genética , Streptomyces/genética , Sequenciamento Completo do Genoma , Antraciclinas/uso terapêutico , Daunorrubicina/biossíntese , Daunorrubicina/química , Doxorrubicina/biossíntese , Doxorrubicina/química , Humanos , Anotação de Sequência Molecular , Policetídeo Sintases/biossíntese , Policetídeo Sintases/química , Metabolismo Secundário/genética , Streptomyces/química , Streptomyces/metabolismo
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