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1.
Frontiers of Medicine ; (4): 339-351, 2023.
Artigo em Inglês | WPRIM | ID: wpr-982565

RESUMO

Ketone bodies have beneficial metabolic activities, and the induction of plasma ketone bodies is a health promotion strategy. Dietary supplementation of sodium butyrate (SB) is an effective approach in the induction of plasma ketone bodies. However, the cellular and molecular mechanisms are unknown. In this study, SB was found to enhance the catalytic activity of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2), a rate-limiting enzyme in ketogenesis, to promote ketone body production in hepatocytes. SB administrated by gavage or intraperitoneal injection significantly induced blood ß-hydroxybutyrate (BHB) in mice. BHB production was induced in the primary hepatocytes by SB. Protein succinylation was altered by SB in the liver tissues with down-regulation in 58 proteins and up-regulation in 26 proteins in the proteomics analysis. However, the alteration was mostly observed in mitochondrial proteins with 41% down- and 65% up-regulation, respectively. Succinylation status of HMGCS2 protein was altered by a reduction at two sites (K221 and K358) without a change in the protein level. The SB effect was significantly reduced by a SIRT5 inhibitor and in Sirt5-KO mice. The data suggests that SB activated HMGCS2 through SIRT5-mediated desuccinylation for ketone body production by the liver. The effect was not associated with an elevation in NAD+/NADH ratio according to our metabolomics analysis. The data provide a novel molecular mechanism for SB activity in the induction of ketone body production.


Assuntos
Camundongos , Animais , Ácido Butírico/metabolismo , Corpos Cetônicos/metabolismo , Fígado/metabolismo , Hidroxibutiratos/metabolismo , Regulação para Baixo , Sirtuínas/metabolismo , Hidroximetilglutaril-CoA Sintase/metabolismo
2.
Journal of Forensic Medicine ; (6): 212-216, 2022.
Artigo em Inglês | WPRIM | ID: wpr-984111

RESUMO

OBJECTIVES@#To find a method to distinguish exogenous gamma-hydroxybutyrate (GHB) from endogenous GHB by establishing ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) based on exosome for quantitative detection of GHB in the rat blood.@*METHODS@#Adult male SD rats were divided into 1 h, 5 h, 10 h administration group and control group. After 1 h, 5 h and 10 h of single precursor of GHB gamma-butyrolactone (GBL) intraperitoneal injection in administration groups, 5 mL blood was collected from the abdominal aorta. Meanwhile, the control group was given a same dose of normal saline, and 5 mL blood was collected at 1 h. Among the 5 mL blood, 0.5 mL was directly detected by HPLC-MS after pretreatment, and exosomes were extracted from the remaining blood by differential centrifugation and detected.@*RESULTS@#The concentration of GHB in the control group was (87.36±33.48) ng/mL, and the concentration with administration at 1 h, 5 h and 10 h was (110 400.00±1 766.35) ng/mL, (1 479.00±687.01) ng/mL and (133.60±12.17) ng/mL, respectively. The results of exosome detection showed that no peak GHB signal was detected in the control group and the 10 h administration group, and the concentrations of GHB at 1 h and 5 h administration groups were (91.47±33.44) ng/mL and (49.43±7.05) ng/mL, respectively.@*CONCLUSIONS@#GHB was detected in blood exosome by UPLC-MS, which indicated that exogenous GHB could be detected in plasma exosomes, while endogenous GHB could not be detected, suggesting that this method may be used as a basis to determine whether there is exogenous drug intake.


Assuntos
Animais , Masculino , Ratos , 4-Butirolactona/química , Cromatografia Líquida , Exossomos/química , Hidroxibutiratos/química , Ratos Sprague-Dawley , Oxibato de Sódio/análise , Espectrometria de Massas em Tandem/métodos
3.
Electron J Biotechnol ; 49: 22-28, Jan. 2021. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1291938

RESUMO

BACKGROUND: Vibrio species display variable and plastic fitness strategies to survive and interact with multiple hosts, including marine aquaculture species that are severely affected by pathogenic Vibrios. The culturable Vibrio sp. strain ArtGut-C1, the focus of this study, provides new evidence of such phenotypic plasticity as it accumulates polyhydroxybutyrate (PHB), a biodegradable polymer with anti-pathogen activity, particularly in the marine larviculture phase. The strain was isolated from the gut of laboratory-reared Artemia individuals, the live diet and PHB carrier used in larviculture. Its main phenotypic properties, taxonomic status and genomic properties are reported based on the whole-genome sequencing. RESULTS: Vibrio sp. ArtGut-C1 yielded 72.6% PHB of cells' dry weight at 25 C. The genomic average nucleotide identity (ANI) shows it is closely related to V. diabolicus (ANI: 88.6%). Its genome contains 5,236,997- bp with 44.8% GC content, 3,710 protein-coding sequences, 96 RNA, 9 PHB genes functionally related to PHB metabolic pathways, and several genes linked to competing and colonizing abilities. CONCLUSIONS: This culturable PHB-accumulating Vibrio strain shows high genomic and phenotypic variability. It may be used as a natural pathogen biocontrol in the marine hatchery and as a potential cell factory for PHB production.


Assuntos
Animais , Artemia/microbiologia , Vibrio/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Hidroxibutiratos/metabolismo , Variação Genética , Vibrio/isolamento & purificação , Vibrio/classificação , Aquicultura , Probióticos , Crustáceos/microbiologia , Microbioma Gastrointestinal , Variação Biológica da População
4.
Chinese Journal of Biotechnology ; (12): 196-206, 2021.
Artigo em Chinês | WPRIM | ID: wpr-878554

RESUMO

Polyhydroxyalkanoates (PHAs) have obtained much attention in biomaterial fields due to their similar physicochemical properties to those of the petroleum-derived plastics. Poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] is one member of the PHAs family, and has better toughness and transparency compared to existing polylactic acid (PLA) and poly[(R)-3-hydroxybutyrate] [P(3HB)]. First, we confirmed the one-step biosynthesis of P(LA-co-3HB) with the lactate fraction of 23.8 mol% by introducing P(3HB-co-LA) production module into Escherichia coli MG1655. Then, the lactate fraction was increased to 37.2 mol% in the dld deficient strain WXJ01-03. The genes encoding the thioesterases, ydiI and yciA, were further knocked out, and the lactate fraction in the P(3HB-co-LA) was improved to 42.3 mol% and 41.1 mol% respectively. Strain WXJ03-03 with dld, ydiI and yciA deficient was used for the production of the LA-enriched polymer, and the lactate fraction was improved to 46.1 mol%. Notably, the lactate fraction in P(3HB-co-LA) from xylose was remarkably higher than from glucose, indicating xylose as a potent carbon source for P(3HB-co-LA) production. Therefore, the deficiency of thioesterase may be considered as an effective strategy to improve the lactate fraction in P(3HB-co-LA) in xylose fermentation.


Assuntos
Escherichia coli/genética , Hidroxibutiratos , Ácido Láctico , Poliésteres , Poli-Hidroxialcanoatos , Xilose
5.
Chinese Journal of Biotechnology ; (12): 4231-4242, 2021.
Artigo em Chinês | WPRIM | ID: wpr-921501

RESUMO

2-Hydroxybutyric acid (2-HBA) is an important intermediate for synthesizing biodegradable materials and various medicines. Chemically synthesized racemized 2-HBA requires deracemization to obtain optically pure enantiomers for industrial application. In this study, we designed a cascade biosynthesis system in Escherichia coli BL21 by coexpressing L-threonine deaminase (TD), NAD-dependent L-lactate dehydrogenase (LDH) and formate dehydrogenase (FDH) for production of optically pure (S)-2-HBA from bulk chemical L-threonine (L-Thr). To coordinate the production rate and the consumption rate of the intermediate 2-oxobutyric acid in the multi-enzyme cascade catalytic reactions, we explored promoter engineering to regulate the expression levels of TD and FDH, and developed a recombinant strain P21285FDH-T7V7827 with a tunable system to achieve a coordinated multi-enzyme expression. The recombinant strain P21285FDH-T7V7827 was able to efficiently produce (S)-2-HBA with the highest titer of 143 g/L and a molar yield of 97% achieved within 16 hours. This titer was approximately 1.83 times than that of the highest yield reported to date, showing great potential for industrial application. Our results indicated that constructing a multi-enzyme-coordinated expression system in a single cell significantly contributed to the biosynthesis of hydroxyl acids.


Assuntos
Escherichia coli/genética , Formiato Desidrogenases , Hidroxibutiratos , Treonina Desidratase
6.
Electron. j. biotechnol ; 48: 36-45, nov. 2020. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1254948

RESUMO

Azotobacter vinelandii is a gram-negative soil bacterium that produces two biopolymers of biotechnological interest, alginate and poly(3-hydroxybutyrate), and it has been widely studied because of its capability to fix nitrogen even in the presence of oxygen. This bacterium is characterized by its high respiration rates, which are almost 10-fold higher than those of Escherichia coli and are a disadvantage for fermentation processes. On the other hand, several works have demonstrated that adequate control of the oxygen supply in A. vinelandii cultivations determines the yields and physicochemical characteristics of alginate and poly(3-hydroxybutyrate). Here, we summarize a review of the characteristics of A. vinelandii related to its respiration systems, as well as some of the most important findings on the oxygen consumption rates as a function of the cultivation parameters and biopolymer production.


Assuntos
Respiração , Biopolímeros/biossíntese , Azotobacter vinelandii/fisiologia , Poliésteres , Alginatos , Bactérias Gram-Negativas/fisiologia , Hidroxibutiratos , Fixação de Nitrogênio
7.
Electron. j. biotechnol ; 46: 8-13, jul. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1223212

RESUMO

BACKGROUND: Poly-3-hydroxybutyrate (PHB) can be efficiently produced in recombinant Escherichia coli by the overexpression of an operon (NphaCAB) encoding PHB synthetase. Strain improvement is considered to be one of critical factors to lower the production cost of PHB in recombinant system. In this study, one of key regulators that affect the cell growth and PHB content was confirmed and analyzed. RESULT: S17-3, a mutant E. coli strain derived from S17-1, was found to be able to achieve high cell density when expressing NphaCAB with the plasmid pBhya-CAB. Whole genome sequencing of S17-3 revealed genetic alternations on the upstream regions of csrA, encoding a global regulator cross-talking between stress response, catabolite repression and other metabolic activities. Deletion of csrA or expression of mutant csrA resulted in improved cell density and PHB content. CONCLUSION: The impact of gene deletion of csrA was determined, dysfunction of the regulators improved the cell density of recombinant E. coli and PHB production, however, the detail mechanism needs to be further clarified.


Assuntos
Escherichia coli/metabolismo , Hidroxibutiratos/metabolismo , Proteínas Repressoras/genética , Biopolímeros/genética , Proteínas Recombinantes , Proteínas de Ligação a RNA/genética , Deleção de Genes , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Engenharia Metabólica , Ligases/metabolismo
8.
Acta cir. bras ; 35(3): e202000303, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1130621

RESUMO

Abstract Purpose: To evaluate the in vivo response of photobiomodulation therapy associated with norbixin-based poly(hydroxybutyrate) membrane (PHB) in tenotomized calcaneal tendon. Methods: Thirty rats were randomly allocated to six groups (n=5 each): LED groups (L1, L2 and L3) and membrane + LED groups (ML1, ML2 and ML3). The right calcaneal tendons of all animals were sectioned transversely and were irradiated with LED daily, one hour after surgery every 24 hours, until the day of euthanasia. At the end of the experiments the tendons were removed for histological analysis. Results: The histological analysis showed a significant reduction in inflammatory cells in the ML1, ML2 and ML3 groups (p=0.0056, p=0.0018 and p<0.0001, respectively) compared to those in the LED group. There was greater proliferation of fibroblasts in the ML1 (p<0.0001) and L3 (p<0.0001) groups. A higher concentration of type I collagen was also observed in the ML1 group (p=0.0043) replacing type III collagen. Conclusion: Photobiomodulation in association with norbixin-based PHB membrane led to control of the inflammatory process. However, it did not favor fibroblast proliferation and did not optimize type I collagen formation in the expected stage of the repair process.


Assuntos
Animais , Masculino , Ratos , Tendão do Calcâneo/efeitos da radiação , Carotenoides/farmacologia , Terapia com Luz de Baixa Intensidade/métodos , Tendinopatia/radioterapia , Tenotomia/métodos , Hidroxibutiratos/farmacologia , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Distribuição Aleatória , Colágeno/farmacologia , Ratos Wistar , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/efeitos dos fármacos , Fibroblastos/química , Proibitinas
9.
Acta cir. bras ; 35(7): e202000706, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1130664

RESUMO

Abstract Purpose To synthesize and characterize poly(hydroxybutyrate) (PHB) and norbixin membranes to evaluate them for genotoxicity in rats and wound healing in mice by histological staining. Methods For the evaluation of genotoxicity, male rats ( Rattus novegicus ) were divided into three groups (n= 5): 5% PHB/Norbixin membrane introduced into the peritoneum by laparotomy; B - negative control; C - positive control (intraperitoneal dose of cyclophosphamide 50 mg/kg). For the evaluation of biocompatibilty, a cutaneous wound was induced on the back of males mice ( Mus musculus ) divided into two experimental treatment groups: control and membrane that underwent euthanasia after 7 and 14 days treatment. Statistical analysis ware made by One Way Anova post hoc Tukey Test (p<0.05). Results Regarding the incidence of polychromatic erythrocytes, there was no difference between negative control and 5% PHB/Norbixin membrane; however, when compared to the positive control represented by cyclophosphamide, there was a significant difference (p <0.001). As for DNA damage, the changes induced in the first 4h were repaired in 24h. In addition, the membrane was effective in abbreviating the inflammatory process and served as a scaffold due to the stimulus to reepithelialization mainly on the 7 days of treatment. Conclusion The non-genotoxic PHB/Norbixin 5% membrane presented promising results that suggest its effectiveness as a guide for tissue regeneration given its biocompatibility.


Assuntos
Carotenoides/toxicidade , Hidroxibutiratos/toxicidade , Poliésteres , Cicatrização , Dano ao DNA , Proibitinas
10.
Acta cir. bras ; 34(11): e201901101, Nov. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054681

RESUMO

Abstract Purpose: To determine the efficacy of norbixin-based poly(hydroxybutyrate) (PHB) membranes for Achilles tendon repair. Methods: Thirty rats were submitted to total tenotomy surgery of the right Achilles tendon and divided into two groups (control and membrane; n = 15 each), which were further subdivided into three subgroups (days 7, 14, and 21; n = 5 each). Samples were analyzed histologically. Results: Histological analysis showed a significant reduction in inflammatory infiltrates on days 7, 14 (p < 0.0001 for both), and 21 (p = 0.0004) in the membrane group compared to that in the control group. There was also a significant decrease in the number of fibroblasts in the control group on days 7, 14 (p < 0.0001), and 21 (p = 0.0032). Further, an increase in type I collagen deposition was observed in the membrane group compared to that in the control group on days 7 (p = 0.0133) and 14 (p = 0.0107). Conclusion: Treatment with norbixin-based PHB membranes reduces the inflammatory response, increases fibroblast proliferation, and improves collagen production in the tendon repair region, especially between days 7 and 14.


Assuntos
Humanos , Animais , Masculino , Poliésteres/farmacologia , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/efeitos dos fármacos , Carotenoides/farmacologia , Tenotomia/métodos , Hidroxibutiratos/farmacologia , Valores de Referência , Regeneração/efeitos dos fármacos , Tendão do Calcâneo/patologia , Reprodutibilidade dos Testes , Ratos Wistar , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos
11.
Braz. j. med. biol. res ; 50(1): e5492, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-839240

RESUMO

The conventional method for quantification of polyhydroxyalkanoates based on whole-cell methanolysis and gas chromatography (GC) is laborious and time-consuming. In this work, a method based on flow cytometry of Nile red stained bacterial cells was established to quantify poly-3-hydroxybutyrate (PHB) production by the diazotrophic and plant-associated bacteria, Herbaspirillum seropedicae and Azospirillum brasilense. The method consists of three steps: i) cell permeabilization, ii) Nile red staining, and iii) analysis by flow cytometry. The method was optimized step-by-step and can be carried out in less than 5 min. The final results indicated a high correlation coefficient (R2=0.99) compared to a standard method based on methanolysis and GC. This method was successfully applied to the quantification of PHB in epiphytic bacteria isolated from rice roots.


Assuntos
Azospirillum brasilense/metabolismo , Citometria de Fluxo/métodos , Herbaspirillum/metabolismo , Hidroxibutiratos/metabolismo , Raízes de Plantas/microbiologia , Poliésteres/metabolismo , Microscopia de Fluorescência
12.
Chinese Journal of Biotechnology ; (12): 738-747, 2016.
Artigo em Chinês | WPRIM | ID: wpr-337426

RESUMO

In this review, we presented the industrial status of biomanufactured polyhydroxyalkanoates (PHA), including poly (3-hydroxybutyrate) (PHB), poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P3/4HB)), and poly (3-hydroxybutyrate-3-hydroxycaproate) (PHBH). A lot of modification studies, aimed at solving problems of poor thermal stability, narrow processing window and other drawbacks of PHA, are discussed. The properties of PHA can be optimized by using proper modification method, in order to expand its applications.


Assuntos
Ácido 3-Hidroxibutírico , Biotecnologia , Hidroxibutiratos , Poliésteres , Poli-Hidroxialcanoatos , Química
13.
Chinese Journal of Biotechnology ; (12): 659-669, 2015.
Artigo em Chinês | WPRIM | ID: wpr-240611

RESUMO

Halohydrin dehalogenase is of great significance for biodegradation of the chlorinated pollutants, and also serves as an important biocatalyst in the synthesis of chiral pharmaceutical intermediates. A putative halohydrin dehalogenase (HheTM) gene from Tistrella mobilis KA081020-065 was cloned and over-expressed in Escherichia coli BL21 (DE3). The recombinant enzyme was purified by Ni-NTA column and characterized. Gel filtration and SDS-PAGE analysis showed that the native form of HheTM was a tetramer. It exhibited the highest activity at 50 degrees C. The nature and pH of the buffer had a great effect on its activity. The enzyme maintained high stability under the alkaline conditions and below 30 degrees C. HheTM catalyzed the transformation of ethyl(S)-4-chloro-3-hydroxybutyrate in the presence of cyanide, to give ethyl (R)-4-cyano-3-hydroxybutyrate, a key intermediate for the synthesis of atorvastatin.


Assuntos
Ácido 3-Hidroxibutírico , Química , Proteínas de Bactérias , Genética , Metabolismo , Clonagem Molecular , Escherichia coli , Hidrolases , Genética , Metabolismo , Hidroxibutiratos , Química , Proteínas Recombinantes , Genética , Metabolismo , Rhodospirillaceae , Genética
14.
Chinese Journal of Integrated Traditional and Western Medicine ; (12): 1427-1432, 2015.
Artigo em Chinês | WPRIM | ID: wpr-286367

RESUMO

<p><b>OBJECTIVE</b>To observe metabolomic changes in urine of chronic superficial gastritis (CSG) patients with Pi-qi deficiency syndrome (PQDS) or Pi-Wei dampness-heat syndrome (PWDHS), thereby providing scientific evidence for syndrome typing of them.</p><p><b>METHODS</b>Urine samples were collected from CSG patients with PQDS/PWDHS and healthy volunteers, 10 in each group. Proton nuclear magnetic resonance spectroscopy (1H-NMR) based metabonomic analysis was performed on urine samples. Contents of related biomarkers were analyzed by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA), and urivariate statistical analysis.</p><p><b>RESULTS</b>PLS-DA analysis showed that metabolites among CSG patients with PQDS/PWDHS and healthy volunteers could be mutually distinguished. Seven differentially identified metabolites were screened from urines of CSG patients with PQDS and healthy volunteers included glutamate, methionine, α-oxoglutarate, dimethylglycine, creatinine, taurine, and glucose. Four differentially identified metabolites were screened from urines of CSG patients with PWDHS and healthy volunteers included 2-hydroxybutyric acid, trimethylamine oxide, taurine, and hippuric acid. Eleven differentially identified metabolites were screened from urines of CSG patients with PQDS and PWDHS included fucose, β-hydroxybutyric acid, alanine, glutamate, methionine, succinic acid, citric acid, creatinine, glucose, hippuric acid, and lactic acid.</p><p><b>CONCLUSION</b>The metabolic differences of CSG patients PQDS and PWDHS mainly manifested in glycometabolism, lipid metabolism, and amino acids catabolism, and 1H-NMR based metabonomics may be used in classified study of Chinese medical syndrome typing.</p>


Assuntos
Humanos , Biomarcadores , Urina , Análise Discriminante , Gastrite , Urina , Temperatura Alta , Hidroxibutiratos , Ácidos Cetoglutáricos , Análise dos Mínimos Quadrados , Medicina Tradicional Chinesa , Metaboloma , Fisiologia , Metabolômica , Análise de Componente Principal , Espectroscopia de Prótons por Ressonância Magnética , Qi , Síndrome
15.
Journal of Forensic Medicine ; (6): 200-203, 2015.
Artigo em Chinês | WPRIM | ID: wpr-983988

RESUMO

OBJECTIVE@#To establish the method to analyze γ-hydroxybutyric acid (GHB) and its precursors 1,4-butanediol (1,4-BD) and gamma-butyrolactone (GBL) in urine through LC-MS/MS and provide evidence for related cases.@*METHODS@#GHB-d6 and MOR-d3 were used as the internal standard. The urine sample was separated by LC after protein precipitation with methanol. The electrospray ion source was for ionization. Each compound was detected through multiple-reaction monitoring (MRM) mode.@*RESULTS@#The limits of detection of GHB and its precursors 1,4-BD and GBL were 0.1, 0.1 and 2 μg/mL. The accuracy was 87.6%-98.1%. The intra-day and inter-day precisions were less than 15% and matrix effects were higher than 80%.@*CONCLUSION@#The method is high sensitive, simple, rapid, specific and with high reliability. This study has provided technical support and basic data for forensic cases involving GHB.


Assuntos
Humanos , 4-Butirolactona/urina , Butileno Glicóis/urina , Cromatografia Líquida , Ciências Forenses , Hidroxibutiratos/urina , Espectrometria de Massas , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
16.
Chinese Journal of Biotechnology ; (12): 1504-1514, 2013.
Artigo em Chinês | WPRIM | ID: wpr-242461

RESUMO

1,3-propanediol production with the byproduct of biodiesel production is important to increase the economic benefit of biodiesel industry. Accumulation of 3-hydroxypropionaldehyde is one of the key problems in the 1,3-propanediol fermentation process, leading to the cell death and the fermentation abnormal ceasing. Different from the traditional way of reducing the accumulation of the 3-hydroxypropionaldehyde, we introduced the polyhydroxybutyrate pathway into the Klebsiella pneumoniae for the first time to enhance the tolerance of K. pneumoniae to 3-hydroxypropionaldehyde, at the same time, to improve the 1,3-propanediol production. Plasmid pDK containing phbC, phbA, phbB gene was constructed and transformed into K. pneumoniae successfully. PHB was detected in the engineered K. pneumoniae after IPTG induction and its content enhanced with the IPTG concentration increasing. The optimized IPTG concentration was 0.5 mmol/L. The constructed K. pneumoniae could produce 1,3-propanediol normally, at the same time accumulate polyhydroxybutyrate. With the constructed strain, the fermentation proceeds normally with the initial glucose was 70 g/L which the wild type strain stopped growing and the fermentation was ceasing; 1,3-propanediol concentration and yield reached 31.3 g/L and 43.9% at 72 h. Our work is helpful for the deep understanding of 1,3-propanediol metabolic mechanism of Klebsiella pneumoniae, and also provides a new way for strain optimization of Klebsiella pneumoniae.


Assuntos
Engenharia Genética , Métodos , Hidroxibutiratos , Metabolismo , Microbiologia Industrial , Métodos , Klebsiella pneumoniae , Genética , Metabolismo , Polímeros , Metabolismo , Propilenoglicóis , Metabolismo
17.
Artigo em Espanhol | LILACS | ID: lil-728070

RESUMO

El presente texto hace un breve recorrido sobre los usos terapéuticos que han tenido la LSD, MDMA, THC, GHB, DMT, Psilocybina y Mescalina en la historia, así como también refiere algunos de los beneficios para la salud física y mental que se considera tienen en la actualidad. Esta información científica se contrapone a la normativa internacional en materia de drogas, que las clasifica como sustancias prohibidas en la Lista I, debido a su falta de uso médico aceptado por Estados Unidos y a su alto potencial de abuso. En este trayecto también se intenta comprender a qué hace referencia dicho potencial, así como las motivaciones que podrían existir detrás de la prohibición del uso terapéutico de estas drogas. En este marco, se consideran consecuencias para la salud de la población, las que atentan contra los Derechos Humanos de las personas que podrían requerir alguna de estas sustancias.


This paper makes a brief of the therapeutic uses have had the LSD, MDMA, THC, GHB, DMT, Psilocybin and Mescaline in history, as well as some of the benefits referred to physical and mental health that are considered today. This scientific information seems contrary to international legislation on drugs, which classifies as prohibited substances in Schedule I, due to its lack of acceptance medical use by the United States and its high potential for abuse. In this way also try to understand what makes this potential reference, and the reasons that could be behind the ban on therapeutic use of these drugs. In this framework, we consider health consequences of the population, which violate the human rights of people who may require some of these substances.


Assuntos
Humanos , Alucinógenos/uso terapêutico , Psicotrópicos/uso terapêutico , Drogas Ilícitas , Dietilamida do Ácido Lisérgico/uso terapêutico , Dronabinol/uso terapêutico , Direitos Humanos , Hidroxibutiratos/uso terapêutico , Mescalina/uso terapêutico , N,N-Dimetiltriptamina/uso terapêutico , /uso terapêutico , Psilocibina/uso terapêutico
18.
Chinese Journal of Biotechnology ; (12): 48-55, 2012.
Artigo em Chinês | WPRIM | ID: wpr-304514

RESUMO

4-Hydroxybutyric acid (4HB) is a psychotropic drug used for polymer synthesis such as poly (4-hydroxybutyric acid) (P4HB) and poly (3-hydroxybutyric acid-co-4-hydroxybutyric acid) (P3HB-co-4HB). 1,4-butanediol (BD) can be converted to 4-hydroxybutyric acid by alcohol dehydrogenase (DhaT) and aldehyde dehydrogenase (AldD). In this study, high efficiency promoters including T7 promoter and P(Re) promoter were cloned to increase expression of dhaT and aldD, and thus accelerate the conversion from BD to 4HB. A. hydrophila 4AK4 (pZQ01), the recombinant strain under the control of T7 promoter, produced 6.00 g/L 4HB from 10 g/L BD with the productivity increased by 43.20%. While A. hydrophila 4AK4 (pZQ04), the strain under the control of T7 promoter, produced 4.87 g/L 4HB from 10 g/L BD, and the productivity was increased by 16.23%. Thus, the gene expression was increased by T7 and P(Re) promoters, leading to an accelerated biosynthesis of 4HB.


Assuntos
Aeromonas hydrophila , Genética , Metabolismo , Engenharia Genética , Hidroxibutiratos , Metabolismo , Regiões Promotoras Genéticas , Genética , Recombinação Genética
19.
Chinese Journal of Biotechnology ; (12): 998-1004, 2011.
Artigo em Chinês | WPRIM | ID: wpr-324510

RESUMO

Cyanobacteria have become attractive hosts for renewable chemicals production. The low productivity, however, prevents it from industrial application. Reductant NAD(P)H availability is a chief hurdle for the production of reductive metabolites in microbes. To increase NADPH content in Synechocystis sp. PCC 6803, PHB synthase encoding gene phaC and phaE in Synechocystis was inactivated by replacing phaC&E genes with chloromycetin resistance cassette via homologous recombination. PCR analysis showed that mutant S.delta phaC&E with complete genome segregation was generated. The comparison between growth curves of S.wt and S.delta phaC&E indicated the knockout of phaC & phaE genes did not affect obviously the cell growth. Gas chromatography analysis showed that the accumulation of PHB in wild type was about 2.3% of the dry cell weight, whereas no PHB was detected in the mutant S.delta phaC&E. The data indicated that inactivation of PHB synthase gene phaC and phaE interrupted the synthesis of PHB. Further comparative study of wild type and mutant demonstrated that NADPH content in S.delta phaC&E was obviously increased. On the third day, the NADPH content in S.delta phaC&E was up to 1.85 fold higher than that in wild type. These results indicated that deleting PHB synthase gene phaC and phaE not only can block the synthesis of PHB, but also can save NADPH to contribute reductant sink in cyanobacteria. Hence, the engineered cyanobacterial strain S.delta phaC&E, in which carbon flux was redirected and NADPH was increased, will be a potential host strain for chemicals production in cyanobacteria.


Assuntos
Escherichia coli , Genética , Metabolismo , Técnicas de Inativação de Genes , Hidroxibutiratos , Metabolismo , Engenharia Metabólica , Mutação , NADP , Metabolismo , Poliésteres , Metabolismo , Proteínas Recombinantes , Genética , Metabolismo , Substâncias Redutoras , Metabolismo , Synechocystis , Genética , Metabolismo
20.
Chinese Journal of Biotechnology ; (12): 1749-1754, 2011.
Artigo em Chinês | WPRIM | ID: wpr-304525

RESUMO

Besides medical application, 4-hydroxybutyrate (4-HB) is a precursor of P3HB4HB, a bioplastic showing excellent physical properties and degradability. Escherichia coli S17-1 (pZL-dhaT-aldD) can transform 1, 4-butanediol (1,4-BD) into 4HB with participation of cofactor NAD. To enhance productivity, nicotinic acid phosphoribosyltransferase (PncB) and nicotinamide adenine dinucleotide synthetase (NadE) were overexpressed to increase intracellular nicotinamide adenine dinucleotide concentration and promote reaction process. The shake flask fermentation result showed that the conversion rate increased by 13.03% with help of PncB-NadE, leading to 4.87 g/L 4HB from 10 g/L 1,4-BD, and productivity was increased by 40.91% to 1.86 g/g. These results demonstrated that expression of PncB and NadE is beneficial for conversion of 1,4-BD to 4HB.


Assuntos
Amida Sintases , Metabolismo , Butileno Glicóis , Química , Metabolismo , Escherichia coli , Metabolismo , Fermentação , Hidroxibutiratos , Química , Metabolismo , Pentosiltransferases , Metabolismo
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