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1.
J Biochem Mol Toxicol ; 38(4): e23676, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561971

RESUMO

Although the treatment of ovarian cancer has made great progress, there are still many patients who are not timely detected and given targeted therapy due to unknown pathogenesis. Recent studies have found that hsa_circ_0015326 is upregulated in ovarian cancer and is involved in the proliferation, invasion, and migration of ovarian cancer cells. However, whether hsa_circ_0015326 can be used as a new target of ovarian cancer needs further investigation. Therefore, the effect of hsa_circ_0015326 on epithelial ovarian cancer was investigated in this study. At first, si-hsa_circ_0015326 lentivirus was transfected into epithelial ovarian cancer cells. Then real-time fluorescence quantitative PCR (qRT-PCR) was used to detect hsa_circ_0015326 level. The proliferation of ovarian cancer cells was detected by CCK-8 assay. The horizontal and vertical migration abilities of the cells were detected by wound-healing assay and Transwell assay, respectively. Transwell assay was also used to determine the invasion rate. As for the apoptosis rate, it was assessed by flow cytometry. As a result, the expression level of hsa_circ_0015326 in A2780 and SKOV3 was found to be higher than that in IOSE-80. However, after transfecting si-hsa_circ_0015326 and si-NC into the cells, the proliferation, migration, and invasion abilities of A2780 and SKOV3 cells in the si-hsa_circ_0015326 group were significantly reduced in comparison to those in the si-NC and mock groups, while their apoptosis rates were elevated. Collectively, silencing hsa_circ_0015326 bears the capability of inhibiting the proliferation, migration, and invasion of ovarian cancer cells while increasing apoptosis rate. It can be concluded that hsa_circ_0015326 promotes the malignant biological activities of epithelial ovarian cancer cells.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Feminino , RNA/metabolismo , Carcinoma Epitelial do Ovário/genética , RNA Circular/genética , RNA Circular/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proliferação de Células , Apoptose , MicroRNAs/metabolismo , Movimento Celular
2.
J Agric Food Chem ; 71(30): 11534-11543, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37463315

RESUMO

Bisabolene is a bioactive sesquiterpene with a wide range of applications in food, cosmetics, medicine, and aviation fuels. Microbial production offers a green, efficient, and sustainable alternative. In this study, we focused on improving the titers of α-bisabolene in Yarrowia lipolytica by applying two strategies, (i) optimizing the metabolic flux of α-bisabolene biosynthetic pathway and (ii) sequestering α-bisabolene in lipid droplet, thus alleviating its inherent toxicity to host cells. We showed that overexpression of DGA1 and OLE1 to increase lipid content and unsaturated fatty acid levels was essential for boosting the α-bisabolene synthesis when supplemented with auxiliary carbon sources. The final engineered strain Po1gαB10 produced 1954.3 mg/L α-bisabolene from the waste cooking oil under shake flask fermentation, which was 96-fold higher than the control strain Po1gαB0. At the time of writing, our study represents the highest reported α-bisabolene titer in the engineered Y. lipolytica cell factory. This work describes novel strategies to improve the bioproduction of α-bisabolene that potentially may be applicable for other high-value terpene products.


Assuntos
Sesquiterpenos , Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Engenharia Metabólica , Gotículas Lipídicas/metabolismo , Terpenos/metabolismo , Sesquiterpenos/metabolismo
3.
J Cancer Res Clin Oncol ; 149(12): 10771-10780, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37316692

RESUMO

PURPOSE: ASTRIS study aimed the largest to evaluate the effectiveness and safety of second- or higher-line osimertinib in patients with advanced/metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC) in the real-world setting. Here we report the results of Chinese patients in ASTRIS study. METHODS: Adults with EGFR T790M-positive advanced NSCLC pretreated with EGFR-tyrosine kinase inhibitor (EGFR-TKI), having a WHO performance status score of 0-2 and asymptomatic, stable central nervous system (CNS) metastases were included. All patients received once-daily osimertinib 80 mg orally. The outcomes included investigator-assessed clinical response, progression-free survival (PFS), time-to-treatment discontinuation (TTD), and safety. RESULTS: A total of 1350 patients were included. Response rate was 55.7% (95% confidence interval [CI] 0.53-0.58). The median PFS and the median TTD were 11.7 months (95% CI 11.1-12.5) and 13.9 months (95% CI 13.1-15.2), respectively. Overall, 389 patients (28.8%) had at least one protocol-specified adverse event (AE); AEs of interstitial lung diseases/pneumonitis-like events and QT prolongation were reported in 3 (0.2%) and 59 (4.4%) patients, respectively. CONCLUSION: Osimertinib was effective in Chinese patients with T790M-positive NSCLC who had progressed after first- or second-generation EGFR-TKI in real-word setting and the results were consistent with ASTRIS study overall population and AURA studies. No new safety signals or events were identified. CLINICAL TRIAL NUMBER: NCT02474355.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Humanos , Compostos de Anilina/efeitos adversos , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , População do Leste Asiático , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/efeitos adversos
4.
Food Microbiol ; 110: 104157, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36462813

RESUMO

Microbes have evolved multiple mechanisms to resist environmental stresses, which are regulated in complex and delicate ways. Though the role of cell membranes in acid resistance from the perspective of physicochemical properties and membrane proteins has been deeply studied, the function of eisosomes is still in its infancy. In this study, we firstly reported the dynamic changes of eisosomes under acid stress and the decreased acid tolerance of yeasts caused by eisosome disruption. Physiological indicators and non-targeted lipid profiling revealed that eisosome disruption caused changes in multiple lipids and imbalances in lipid homeostasis, which are responsible for membrane integrity damage. Thus the increased infiltration of carboxylic acids and the raised ROS levels were detected in strains with disrupted eisosome assembly, resulting in decreased cellular tolerance. The results here provide novel insights into the acid-resistant mechanism of yeasts from the perspective of the cell membrane subdomain, which has practical impacts on green biological manufacturing and food preservation.


Assuntos
Proteínas de Membrana , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Membrana Celular , Ácidos Carboxílicos , Lipídeos
5.
Signal Transduct Target Ther ; 6(1): 329, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34471087

RESUMO

It's a challenge for detecting the therapeutic targets of a polypharmacological drug from variations in the responsed networks in the differentiated populations with complex diseases, as stable coronary heart disease. Here, in an adaptive, 31-center, randomized, double-blind trial involving 920 patients with moderate symptomatic stable angina treated by 14-day Danhong injection(DHI), a kind of polypharmacological drug with high quality control, or placebo (0.9% saline), with 76-day following-up, we firstly confirmed that DHI could increase the proportion of patients with clinically significant changes on angina-frequency assessed by Seattle Angina Questionnaire (ΔSAQ-AF ≥ 20) (12.78% at Day 30, 95% confidence interval [CI] 5.86-19.71%, P = 0.0003, 13.82% at Day 60, 95% CI 6.82-20.82%, P = 0.0001 and 8.95% at Day 90, 95% CI 2.06-15.85%, P = 0.01). We also found that there were no significant differences in new-onset major vascular events (P = 0.8502) and serious adverse events (P = 0.9105) between DHI and placebo. After performing the RNA sequencing in 62 selected patients, we developed a systemic modular approach to identify differentially expressed modules (DEMs) of DHI with the Zsummary value less than 0 compared with the control group, calculated by weighted gene co-expression network analysis (WGCNA), and sketched out the basic framework on a modular map with 25 functional modules targeted by DHI. Furthermore, the effective therapeutic module (ETM), defined as the highest correlation value with the phenotype alteration (ΔSAQ-AF, the change in SAQ-AF at Day 30 from baseline) calculated by WGCNA, was identified in the population with the best effect (ΔSAQ-AF ≥ 40), which is related to anticoagulation and regulation of cholesterol metabolism. We assessed the modular flexibility of this ETM using the global topological D value based on Euclidean distance, which is correlated with phenotype alteration (r2: 0.8204, P = 0.019) by linear regression. Our study identified the anti-angina therapeutic module in the effective population treated by the multi-target drug. Modular methods facilitate the discovery of network pharmacological mechanisms and the advancement of precision medicine. (ClinicalTrials.gov identifier: NCT01681316).


Assuntos
Angina Estável/tratamento farmacológico , Fármacos Cardiovasculares/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Adolescente , Adulto , Idoso , Angina Estável/genética , Angina Estável/patologia , Método Duplo-Cego , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
6.
Food Microbiol ; 95: 103713, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33397627

RESUMO

Higher alcohols are important flavor substance in alcoholic beverages. The content of α-amino nitrogen (α-AN) in the fermentation system affects the formation of higher alcohols by Saccharomyces cerevisiae. In this study, the effect of α-AN concentration on the higher alcohol productivity of yeast was explored, and the mechanism of this effect was investigated through metabolite and transcription sequence analyses. We screened 12 most likely genes and constructed the recombinant strain to evaluate the effect of each gene on high alcohol formation. Results showed that the AGP1, GDH1, and THR6 genes were important regulators of higher alcohol metabolism in S. cerevisiae. This study provided knowledge about the metabolic pathways of higher alcohols and gave an important reference for the breeding of S. cerevisiae with low-yield higher alcohols to deal with the fermentation system with different α-AN concentrations in the brewing industry.


Assuntos
Álcoois/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fermentação , Aromatizantes , Perfilação da Expressão Gênica , Genes Reguladores , Redes e Vias Metabólicas , Nitrogênio/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
Front Microbiol ; 11: 596306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324376

RESUMO

Baijiu is a traditional distilled beverage in China with a rich variety of aroma substances. 2,3,5,6-tetramethylpyrazine (TTMP) is an important component in Baijiu and has the function of promoting cardiovascular and cerebrovascular health. During the brewing of Baijiu, the microorganisms in jiuqu produce acetoin and then synthesize TTMP, but the yield of TTMP is very low. In this work, 2,3-butanediol dehydrogenase (BDH) coding gene BDH1 and another BDH2 gene were deleted or overexpressed to evaluate the effect on the content of acetoin and TTMP in Saccharomyces cerevisiae. The results showed that the acetoin synthesis of strain α5-D1B2 was significantly enhanced by disrupting BDH1 and overexpressing BDH2, leading to a 2.6-fold increase of TTMP production up to 10.55 mg/L. To further improve the production level of TTMP, the α-acetolactate synthase (ALS) of the pyruvate decomposition pathway was overexpressed to enhance the synthesis of diacetyl. However, replacing the promoter of the ILV2 gene with a strong promoter (PGK1p) to increase the expression level of the ILV2 gene did not result in further increased diacetyl, acetoin and TTMP production. Based on these evidences, we constructed the diploid strains AY-SB1 (ΔBDH1:loxP/ΔBDH1:loxP) and AY-SD1B2 (ΔBDH1:loxP-PGK1p-BDH2-PGK1t/ΔBDH1:loxP-PGK1p-BDH2-PGK1t) to ensure the fermentation performance of the strain is more stable in Baijiu brewing. The concentration of TTMP in AY-SB1 and AY-SD1B2 was 7.58 and 9.47 mg/L, respectively, which represented a 2.3- and 2.87-fold increase compared to the parental strain. This work provides an example for increasing TTMP production in S. cerevisiae by genetic engineering, and highlight a novel method to improve the quality and beneficial health attributes of Baijiu.

8.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4257-4262, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872707

RESUMO

This study is to investigate the compatibility mechanism of Danshen-Chuanxiong drug pair on the pharmacokinetics of four phenolic acids. A UPLC-MS/MS method for quantitative determination of salvianolic acid B( Sal B),rosmarinic acid( RA),lithospermic acid( LA) and ferulic acid( FA) in plasma and heart tissue of rats was established. After single salvianolic acids and Chuanxiong-extract or combined intravenous infusion was given to rats,plasma samples and heart tissues in different time were collected. The chromatographic separation was performed on a BEH C18 column using 0. 15% formic acid-acetonitrile as mobile phase for gradient elution. A triple-quadrupole tandem mass spectrometry equipped with an electrospray ionization source was used as detector operating on multiple-reaction monitoring( MRM) scanning in negative ionization mode. Full validation of UPLC method including calibration curves,accuracy,precision,repeatability and matrix effect was investigated to comply with quantitative analysis requirements for biological samples. There were significant differences in the major pharmacokinetic parameters of Sal B,FA and RA for intravenous infusion of salvianolic acids and Chuanxiong-extract or combined in rat plasma. The AUC of Sal B and FA were increased above 40% and100%,respectively. Their Vd and CL were dropped evidently. t1/2 and Vd of RA increased above 130%. The concentration of four phenolic acids were all increased obviously in heart tissue comparing with single infusion. These results demonstrated that the compatibility mechanism of Danshen-Chuanxiong drug pair showed synergistic effect.


Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Coração/fisiologia , Salvia miltiorrhiza , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Hidroxibenzoatos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
9.
Dis Markers ; 2019: 1601072, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485274

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the prognostic role of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) expression level and the platelet lymphocyte ratio (PLR) level in esophageal squamous cell carcinoma (ESCC) patients. METHODS: 84 ESCC patients who received surgical treatment in our hospital were enrolled in the study. The correlation of each biomarker's level with ESCC patients' clinicopathological characteristics and overall survival (OS) was assessed. RESULTS: The elevated expression rate of T-CTLA-4 (tumor cell CTLA-4) and I-CTLA-4 (interstitial lymphocyte CTLA-4) was 48.8% and 44.0%, respectively. The number of enrolled patients with a higher PLR level (≥119) was 48. The prognostic value of T-CTLA-4, I-CTLA-4, and PLR in ESCC patients was not detected. However, patients with both a low T-CTLA-4 expression level and a low PLR level that had longer OS (p = 0.023) were found. The prognostic role of T-CTLA-4(-) +PLR (-) status in ESCC patients was also confirmed in multivariate analyses (p = 0.027). CONCLUSION: These results demonstrated the potential prognostic value of combined analysis of CTLA-4 and PLR in ESCC patients.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno CTLA-4/sangue , Carcinoma de Células Escamosas/sangue , Neoplasias Esofágicas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
10.
Iran J Biotechnol ; 17(2): e1990, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31457054

RESUMO

BACKGROUND: Enhancing the industrial yeast strains ethyl acetate yield through a precise and seamless genetic manipulation strategy without any extraneous DNA sequences is an essential requisite and significant demand. OBJECTIVES: For increasing the ethyl acetate yield of industrial brewer's yeast strain, all the ATF1 alleles were overexpressed through "self-cloning" integration strategy. MATERIAL AND METHODS: Escherichia coli strain DH5α was utilized for plasmid construction. ATF1 alleles were overexpressed through a precise and seamless insertion of the PGK1 promoter in industrial brewer's yeast strain S6. In addition, growth rates, ATF1 mRNA levels, AATase activity, the fermentation performance of the engineered strains, and gas chromatography (GC) analysis was conducted. RESULTS: The two engineered strains (S6-P-12 and S6-P-30) overexpressed all ATF1 alleles but unaffected normal growth. The ATF1 mRNA levels of the S6-P-12 and S6-P-30 were all 4-fold higher than that of S6. The AATase (Alcohol acetyl transferases, encoded by ATF1 gene) activity of the two engineered strains was all 3-fold higher than that of the parent strain. In the beer fermentation at 10 ℃, the concentrations of ethyl acetate produced by the engineered strains S6-P-12 and S6-P-30 was increased to 23.98 and 24.00 mg L-1, respectively, about 20.44% and 20.54% higher than that of S6. CONCLUSIONS: These results verify that the ethyl acetate yield could be enhanced by the overexpressed of ATF1 in the polyploid industrial brewer's yeast strains via "self-cloning" integration strategy. The present study provides a reference for target gene modification in the diploid or polyploid industrial yeast strains.

11.
J Food Biochem ; 43(7): e12846, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31353733

RESUMO

Cyclic adenosine monophosphate (cAMP) plays an important role in modulating the activity of microbe cell. In this study, PKA (protein kinase A) activity was weakened through truncation of TPK2 promoter (-150 bp and -300 bp) and gene deletion of BCY1 (encodes the regulatory subunit of PKA), TPK1 and TPK3, generating strains BY9a-T2-150 and BY9a-T2-300, respectively. High-performance liquid chromatography analysis showed cAMP levels in BY9a-T2-150 and BY9a-T2-300 were increased by 5- and 18-fold, respectively, compared with that of parent strain, BY9a. The expression levels of TPK2 gene in two engineered strains were decreased by 95% and 97% compared with that of BY9a, respectively. The PKA activity reflected by heat resistance of engineered strains enhanced compared with parent strain BY9a. This study show a new method to increase the intracellular cAMP concentration in industrial yeast by fine-tuning of PKA activity, without influence in growth and fermentation properties. PRACTICAL APPLICATIONS: cAMP as the "second messenger," is essential for plant, animal, and microorganisms and human life. But its synthesis is still limited by expensive cost and time-consuming method. We constructed the industrial baker's yeast with high level of cAMP and desired to be used to produce functional food for relaxing smooth muscle, expanding blood vessels, improving liver function, and promoting nerve regeneration and as a food additive for treating hyperthyreosis and hepatopathy. The methods of two step homologous recombination and backcross operated in this study eliminate the exogenous gene in engineered strains, made it safety to be used in food production. Fine-tuning of PKA activity in engineered strains ensure produce high level of cAMP and exhibit normal growth performance in engineering strains. Therefore, this work is significant in functional foods product and has the potential to be used in practical application.


Assuntos
AMP Cíclico/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Bioengenharia , Proteínas Quinases Dependentes de AMP Cíclico/genética , Deleção de Genes , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
12.
Free Radic Biol Med ; 129: 446-453, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30339882

RESUMO

Radiation-induced lung fibrosis (RILF) is a complication of radiotherapy in thoracic cancer patients. Thalidomide (THD) has a therapeutic effect on fibrotic and inflammatory disorders. The purpose of the current study was to investigate the therapeutic effect of THD on RILF in mice and better understand the underlying regulatory mechanisms of the therapeutic effect. We found that THD mitigated the fibrosis caused by irradiation in mice. The action of THD on RILF was related to the elevation of low levels reactive oxygen species (ROS), which inhibited the transforming growth factor­ß (TGF­ß)/Smad3 signaling pathway through activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). Analysis of the therapeutic effect of THD using Nrf2-/- mouse model confirmed the role of Nrf2 in vivo. In addition, no radioprotective effect of THD on thoracic cancer cell lines was observed. In conclusion, these data showed that THD attenuated RILF in mice, which was mediated by Nrf2-dependent down-regulation of the TGF-ß/Smad3 pathway, suggesting THD as a potential novel agent for RILF prevention.


Assuntos
Fibrose Pulmonar/prevenção & controle , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Proteína Smad3/metabolismo , Talidomida/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Raios X/efeitos adversos , Células A549 , Animais , Linhagem Celular Tumoral , Células Epiteliais , Feminino , Regulação da Expressão Gênica , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Pulmão/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Lesões Experimentais por Radiação/etiologia , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/genética , Células THP-1 , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/genética
13.
J Agric Food Chem ; 66(32): 8556-8565, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30027745

RESUMO

Diacetyl generates an aromatic off-flavor in wine at a high level. The present study expressed α-acetolactate decarboxylase (ALDB) from Lactobacillus plantarum and/or inactivated acetohydroxyacid synthase (Ilv6) in Saccharomyces uvarum, and the effects on diacetyl production and wine flavor in mutants were investigated through sequential fermentation and cofermentation in mixed cultures of S. uvarum and L. plantarum. The diacetyl content of WYDΔ6 (disrupted one ILV6 allele), WYSΔ6 ( ILV6 complete deletion), WYADΔ6 (disrupted one ILV6 allele with aldB expression), and WYASΔ6 ( ILV6 complete deletion with aldB expression) decreased by 25.71%, 41.30%, 47.77%, and 50.00%, respectively, after sequential fermentation and decreased by 15.15%, 26.72%, 35.26%, and 43.80%, respectively, after cofermentation, compared with that of the parental strain. In addition, Ilv6 inactivation not only decreased the acetic acid content but also balanced the flavor profile in wine effectively. This work provided a valuable insight into the metabolic pathway of diacetyl and wine flavor in S. uvarum.


Assuntos
Acetolactato Sintase/genética , Proteínas de Bactérias/metabolismo , Diacetil/metabolismo , Proteínas Fúngicas/genética , Lactobacillus plantarum/genética , Saccharomyces/enzimologia , Vinho/análise , Ácido Acético/análise , Ácido Acético/metabolismo , Acetolactato Sintase/metabolismo , Proteínas de Bactérias/genética , Carboxiliases/genética , Carboxiliases/metabolismo , Diacetil/análise , Fermentação , Proteínas Fúngicas/metabolismo , Deleção de Genes , Redes e Vias Metabólicas , Saccharomyces/genética , Saccharomyces/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Vinho/microbiologia
14.
J Agric Food Chem ; 66(28): 7417-7427, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29939025

RESUMO

Appropriate concentrations and proportion of acetate esters and higher alcohols improve the quality of Chinese Baijiu. To regulate the concentrations of acetate esters in Chinese Baijiu, we constructed a PGK1 promoter library through error-prone PCR. Then, we used an enhanced green fluorescent protein as a reporter to characterize the activities of PGK1p mutants. The PGK1p library contained 28 PGK1p mutants and spanned an activity that ranged between 0.1% and 141% of wild-type PGK1p. Seven PGK1p mutants were characterized by an additional reporter ß-galactosidase and then used for the overexpression of ATF1 with BAT2 deletion in Saccharomyces cerevisiae a45. The production of ethyl acetate in strains A8, A17, A18, A27, A22, A25, A28, and AWT were 1.66-, 3.09-, 10.59-, 13.07-, 15.99-, 22.67-, 24.06-, and 27.22-fold higher than that of the parental strain. The results on alcohol acetyltransferase (AATase) activity showed that the PGK1p library precisely controlled ATF1 expression and regulated the acetate esters production.


Assuntos
Ácido Acético/metabolismo , Ésteres/metabolismo , Fosfoglicerato Quinase/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Vinho/microbiologia , Ácido Acético/análise , Ésteres/análise , Etanol/análise , Etanol/metabolismo , Fermentação , Biblioteca Gênica , Fosfoglicerato Quinase/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Vinho/análise
15.
J Ind Microbiol Biotechnol ; 45(9): 827-838, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29936578

RESUMO

Maltose metabolism of baker's yeast (Saccharomyces cerevisiae) in lean dough is suppressed by the glucose effect, which negatively affects dough fermentation. In this study, differences and interactions among SNF4 (encoding for the regulatory subunit of Snf1 kinase) overexpression and REG1 and REG2 (which encodes for the regulatory subunits of the type I protein phosphatase) deletions in maltose metabolism of baker's yeast were investigated using various mutants. Results revealed that SNF4 overexpression and REG1 and REG2 deletions effectively alleviated glucose repression at different levels, thereby enhancing maltose metabolism and leavening ability to varying degrees. SNF4 overexpression combined with REG1/REG2 deletions further enhanced the increases in glucose derepression and maltose metabolism. The overexpressed SNF4 with deleted REG1 and REG2 mutant ΔREG1ΔREG2 + SNF4 displayed the highest maltose metabolism and strongest leavening ability under the test conditions. Such baker's yeast strains had excellent potential applications.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Proteínas de Transporte/genética , Deleção de Genes , Maltose/metabolismo , Proteína Fosfatase 1/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Fermentação , Regulação Fúngica da Expressão Gênica , Glucose/metabolismo , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Simportadores/genética , Simportadores/metabolismo , Fatores de Transcrição/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
17.
Appl Microbiol Biotechnol ; 102(4): 1783-1795, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29305698

RESUMO

Higher alcohols significantly influence the quality and flavor profiles of Chinese Baijiu. ILV1-encoded threonine deaminase, LEU1-encoded α-isopropylmalate dehydrogenase, and LEU2-encoded ß-isopropylmalate dehydrogenase are involved in the production of higher alcohols. In this work, ILV1, LEU1, and LEU2 deletions in α-type haploid, a-type haploid, and diploid Saccharomyces cerevisiae strains and ILV1, LEU1, and LEU2 single-allele deletions in diploid strains were constructed to examine the effects of these alterations on the metabolism of higher alcohols. Results showed that different genetic engineering strategies influence carbon flux and higher alcohol metabolism in different manners. Compared with the parental diploid strain, the ILV1 double-allele-deletion diploid mutant produced lower concentrations of n-propanol, active amyl alcohol, and 2-phenylethanol by 30.33, 35.58, and 11.71%, respectively. Moreover, the production of isobutanol and isoamyl alcohol increased by 326.39 and 57.6%, respectively. The LEU1 double-allele-deletion diploid mutant exhibited 14.09% increased n-propanol, 33.74% decreased isoamyl alcohol, and 13.21% decreased 2-phenylethanol production, which were similar to those of the LEU2 mutant. Furthermore, the LEU1 and LEU2 double-allele-deletion diploid mutants exhibited 41.72 and 52.18% increased isobutanol production, respectively. The effects of ILV1, LEU1, and LEU2 deletions on the production of higher alcohols by α-type and a-type haploid strains were similar to those of double-allele deletion in diploid strains. Moreover, the isobutanol production of the ILV1 single-allele-deletion diploid strain increased by 27.76%. Variations in higher alcohol production by the mutants are due to the carbon flux changes in yeast metabolism. This study could provide a valuable reference for further research on higher alcohol metabolism and future optimization of yeast strains for alcoholic beverages.


Assuntos
Bebidas Alcoólicas/microbiologia , Ciclo do Carbono/genética , Etanol/metabolismo , Microbiologia de Alimentos/métodos , Hidroliases/genética , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Treonina Desidratase/genética , 3-Isopropilmalato Desidrogenase/genética , 3-Isopropilmalato Desidrogenase/metabolismo , China , Fermentação , Deleção de Genes , Humanos , Hidroliases/metabolismo , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Treonina Desidratase/metabolismo
18.
Biotechnol Prog ; 34(2): 328-336, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29314788

RESUMO

As content and proportion of ethyl acetate is critical to the flavor and quality of beverages, the concise regulation of the ethyl acetate metabolism is a major issue in beverage fermentations. In this study, for ethyl acetate yield regulation, we finely modulated the expression of ATF1 through precise and seamless insertion of serially truncated PGK1 promoter from the 3' end by 100bp steps in the Chinese liquor yeast, CLy12a. The three engineered promoters carrying 100-, 200-, and 300-bp truncations exhibited reduced promoter strength but unaffected growth. These three promoters were integrated into the CLy12a strain, generating strains CLy12a-P-100, CLy12a-P-200, and CLy12a-P-300, respectively. The transcription levels of CLy12a-P-100, CLy12a-P-200, and CLy12a-P-300 were 20%, 17%, and 10% of that of CLy12a-P, respectively. The AATase (alcohol acetyl transferases, encoded by the ATF1 gene) activity of three engineered strains were 36%, 56%, and 62% of that of CLy12a-P. In the liquid fermentation of corn hydrolysate at 30°C, the concentration of ethyl acetate in CLy12a-P-100, CLy12a-P-200, and CLy12a-P-300 were reduced by 28%, 30%, and 42%, respectively, compared to CLy12a-P. These results verifying that the ethyl acetate yield could be gradually enhanced by finely modulating the expression of ATF1. The engineered strain CLy12a-P-200 produced the ethyl acetate concentration with the best sensorial quality compared to the other engineered yeast strains. The method proposed in this work supplies a practical proposal for breeding Chinese liquor yeast strains with finely modulated ethyl acetate yield. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:328-336, 2018.


Assuntos
Acetatos/metabolismo , Engenharia Genética/métodos , Proteínas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Bebidas Alcoólicas/microbiologia , Escherichia coli/genética , Fermentação , Regulação Fúngica da Expressão Gênica , Microrganismos Geneticamente Modificados , Fosfoglicerato Quinase/genética , Regiões Promotoras Genéticas , Proteínas/metabolismo , Zea mays
19.
Oncotarget ; 8(46): 81387-81393, 2017 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-29113398

RESUMO

The purpose was to evaluate the predictive value of baseline neutrophil to lymphocyte ratio (NLR) level in the incidence of grade 3 or higher radiation induced lung injury (RILI) for lung cancer patients. A retrospectively analysis with 166 lung cancer patients was performed. All of the enrolled patients received chemoradiotherapy at our hospital between April 2014 and May 2016. The Cox proportional hazard model was used to identify the potential risk factors for RILI. In this cohort, the incidence of grade 3 or higher RILI was 23.8%. Univariate analysis showed that radiation dose, volume at least received 20Gy (V20), mean lung dose and NLR were significantly associated with the incidence of grade 3 or higher RILI (P = 0.012, 0.008, 0.012, and 0.039, respectively). Multivariate analysis revealed that total dose ≥ 60 Gy, V20 ≥ 20%, mean lung dose ≥ 12 Gy, and NLR ≥ 2.2 were still independent predictive factors for RILI (P = 0.010, 0.043, 0.028, and 0.015, respectively). A predictive model of RILI based on the identified risk factors was established using receiver operator characteristic curves. The results demonstrated that the combination analysis of V20, mean lung dose and NLR was superior to either of the variables alone. Additionally, we found that the constraint of V20 and mean lung dose were meaningful for patients with higher baseline NLR level. If the value of V20 and mean lung dose lower than the threshold value, the incidence of grade 3 or higher RILI for the high NLR level patients could be decreased from 63.3% to 8.7%. Our study showed that radiation dose, V20, mean lung dose and NLR were independent predictors for RILI. Combination analysis of V20, mean lung dose and NLR may provide a more accurate model for RILI prediction.

20.
Microb Cell Fact ; 16(1): 194, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29121937

RESUMO

BACKGROUND: Tup1 is a general transcriptional repressor of diverse gene families coordinately controlled by glucose repression, mating type, and other mechanisms in Saccharomyces cerevisiae. Several functional domains of Tup1 have been identified, each of which has differing effects on transcriptional repression. In this study, we aim to investigate the role of Tup1 and its domains in maltose metabolism of industrial baker's yeast. To this end, a battery of in-frame truncations in the TUP1 gene coding region were performed in the industrial baker's yeasts with different genetic background, and the maltose metabolism, leavening ability, MAL gene expression levels, and growth characteristics were investigated. RESULTS: The results suggest that the TUP1 gene is essential to maltose metabolism in industrial baker's yeast. Importantly, different domains of Tup1 play different roles in glucose repression and maltose metabolism of industrial baker's yeast cells. The Ssn6 interaction, N-terminal repression and C-terminal repression domains might play roles in the regulation of MAL transcription by Tup1 for maltose metabolism of baker's yeast. The WD region lacking the first repeat could influence the regulation of maltose metabolism directly, rather than indirectly through glucose repression. CONCLUSIONS: These findings lay a foundation for the optimization of industrial baker's yeast strains for accelerated maltose metabolism and facilitate future research on glucose repression in other sugar metabolism.


Assuntos
Maltose/metabolismo , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Metabolismo dos Carboidratos , Fermentação , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Proteínas Nucleares/metabolismo , Domínios e Motivos de Interação entre Proteínas/genética , Proteínas Repressoras/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
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