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1.
J Cell Mol Med ; 27(17): 2517-2532, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37448185

RESUMO

The tumour microenvironment (TME) and immunosuppression play an important role in colon cancer (CC) metastasis, which seriously affects the prognosis of CC. G protein subunit gamma 4 (GNG4) has been shown to participate in tumour progression and the tumour mutation burden (TMB) in colorectal cancer. However, the effect of GNG4 on the CC TME and immunology remains elusive. Weighted gene coexpression network analysis (WGCNA) was employed for screening aberrantly expressed genes associated with the immune score, and GNG4 was then selected through prognostic and immune correlation analysis. Based on RNA sequencing data obtained from the TCGA and GEO databases, the expression pattern and immune characteristics of GNG4 were comprehensively examined using a pan-cancer analysis. Upregulation of GNG4 was linked to an adverse prognosis and immune inhibitory phenotype in CC. Pan-cancer analysis demonstrated higher GNG4 expression in tumours than in paired normal tissue in human cancers. GNG4 expression was closely related to prognosis, TMB, immune checkpoints (ICPs), microsatellite instability (MSI) and neoantigens. GNG4 promoted CC cell proliferation, migration and invasion and participated in immune regulation in the TME. Significantly, GNG4 expression was found to negatively correlate with tumour-infiltrating immune cells, ICP, TMB and MSI in CC. GNG4 expression predicted the immunotherapy response in the IMvigor210 cohort, suggesting that GNG4 could be used as a potential biomarker in CC for prognostication and immunology. Moreover, the expression of GNG4 predicted the immunotherapy response of ICB in CC.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Humanos , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Proliferação de Células/genética , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/genética , Bases de Dados Factuais , Redes Reguladoras de Genes , Instabilidade de Microssatélites , Microambiente Tumoral/genética
2.
Cell Mol Biol (Noisy-le-grand) ; 69(5): 174-178, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37571883

RESUMO

C-Met receptor and its ligand hepatocyte growth factor (HGF) are overexpressed in a variety of osteosarcoma cell lines and osteosarcoma pathological samples. It is suggested that c-Met/HGF plays an important role in the development of osteosarcoma. This study aimed to explore the anticancer effect of the c-Met-targeted drug crizotinib on osteosarcoma (OS) cells. The effects of crizotinib on the proliferation of osteosarcoma cells (SaOS2, MG-63 and MNNG) at different concentrations were detected by CCK8. Human osteosarcoma cell line MG-63 was used as an in vitro model to evaluate the effects of 2.5 µM crizotinib, 5.0 µM crizotinib and DMSO on cell apoptosis, cell cycle, migration and invasion. The expression of the c-Met signaling pathway in osteosarcoma cells was detected by western blot. The results showed that crizotinib inhibited the proliferation of cell lines in a concentration-dependent manner. Crizotinib significantly increased the number of apoptotic cells compared with the control group. Compared with the control group, crizotinib increased G0/G1 phase cells and decreased S phase cells. Compared with the control group, crizotinib inhibited the migration and invasion of osteosarcoma cells and decreased the expression of c-Met/Gab1/STAT5. This study will provide a promising therapeutic target and theoretical basis for the clinical application of crizotinib in osteosarcoma.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Proliferação de Células , Linhagem Celular Tumoral , Transdução de Sinais , Osteossarcoma/metabolismo , Apoptose , Neoplasias Ósseas/tratamento farmacológico
3.
Water Sci Technol ; 87(1): 228-238, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36640034

RESUMO

Bioaugmentation is an effective strategy used to speed up the bioremediation of marine oil spills. In the present study, a highly efficient petroleum degrading bacterium (Pseudomonas aeruginosa ZS1) was applied to the bioremediation of simulated crude oil pollution in different sampling sites in the South China Sea. The metabolic pathways of ZS1 to degrade crude oil, the temporal dynamics of the microbial community response to crude oil contamination, and the biofortification process were investigated. The results showed that the abundance and diversity of the microbial community decreased sharply after the occurrence of crude oil contamination. The best degradation rate of crude oil, which was achieved in the samples from the sampling site N3 after the addition of ZS1 bacteria, was 50.94% at 50 days. C13 alkanes were totally oxidized by ZS1 in the 50 days. The degradation rate of solid n-alkanes (C18-C20) was about 70%. Based on the whole genome sequencing and the metabolites analysis of ZS1, we found that ZS1 degraded n-alkanes through the terminal oxidation pathway and aromatic compounds through the catechol pathway. This study provides data support for further research on biodegradation pathways of crude oil and contributes to the subsequent development of more reasonable bioremediation strategies.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Poluição por Petróleo/análise , Alcanos/metabolismo , Petróleo/análise , Bactérias/genética , Bactérias/metabolismo , Redes e Vias Metabólicas , Hidrocarbonetos/metabolismo
4.
Metab Eng ; 73: 270-279, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35961600

RESUMO

L-Homoserine is a valuable amino acid as a platform chemical in the synthesis of various important compounds. Development of microbial strains for high-level L-homoserine production is an attractive research direction in recent years. Herein, we converted a wild-type Escherichia coli to a non-auxotrophic and plasmid-free hyperproducer of L-homoserine using systematically metabolic engineer strategies. First, an initial strain was obtained through regulating L-homoserine degradation pathway and enhancing synthetic flow. To facilitate L-homoserine production, flux-control genes were tuned by optimizing the copy numbers in chromosome, and transport system was modified to promote L-homoserine efflux. Subsequently, a strategy of cofactors synergistic utilization was proposed and successfully applied to achieve L-homoserine hyperproduction. The final engineered strain could efficiently produce 85.29 g/L L-homoserine, which was the highest production level ever reported from a plasmid-free, antibiotic-free, inducer-free and nonauxotrophic strain. These strategies used here can be considered for developing microbial cell factory of other L-aspartate derivatives.


Assuntos
Proteínas de Escherichia coli , Engenharia Metabólica , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Homosserina/genética , Homosserina/metabolismo , Plasmídeos/genética
5.
Cell Mol Biol (Noisy-le-grand) ; 68(3): 356-364, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35988182

RESUMO

At present, there is not enough research about the application of liraglutide nano preparations in perioperative neurocognitive dysfunction. Therefore, the purpose of this study is the mechanism of the effect of liraglutide nano preparations on perioperative neurocognitive dysfunction in aged mice. In this study, 140 male SD rats aged 6-8 weeks were used as the research object, and were divided into 4 groups (n=24) according to the random number table method, which were group C (control group), group S (model group), and treatment. Group (low-dose liraglutide pretreated control group) and DS2 group (high-dose liraglutide pretreated control group) were treated with liraglutide anesthesia to establish a cognitive dysfunction model. Morris water maze experiment was conducted 4 days after anesthesia to compare the escape latency and the number of crossings of the original platform in each group; after 4 days of anesthesia, 18 old mice were randomly selected from each group for fluorescence quantitative polymerase chain reaction (RealTimePCR) and protein Western blotting (Western.Blot) was used to determine the mRNA and protein levels of Caspase-3, Bax and Bcl-2 in the hippocampus; the remaining 6 old mice in each group were taken to observe the pathological changes of the hippocampus neurons by transmission electron microscopy . Compared with saline-treated group, the levels of NF-KB, TNF-a and IL-1ß protein in mice treated with liraglutide decreased and IkB increased significantly (p<0.05). Liraglutide intervention may alleviate non-alcoholic fatty liver in diabetic mice by reducing the expression of inflammatory genes in liver tissue, thereby improving neurocognitive dysfunction in mice.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental , Animais , Disfunção Cognitiva/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Hipocampo/metabolismo , Liraglutida/metabolismo , Liraglutida/farmacologia , Liraglutida/uso terapêutico , Masculino , Camundongos , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley
6.
Ecotoxicol Environ Saf ; 241: 113769, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35738097

RESUMO

In the process of marine oil spill remediation, adding highly efficient oil degrading microorganisms can effectively promote oil degradation. However, in practice, the effect is far less than expected due to the inadaptability of microorganisms to the environment and their disadvantage in the competition with indigenous bacteria for nutrients. In this article, four strains of oil degrading bacteria were isolated from seawater in Jiaozhou Bay, China, where a crude oil pipeline explosion occurred seven years ago. Results of high-throughput sequencing, diesel degradation tests and surface activity tests indicated that Peseudomonas aeruginosa ZS1 was a highly efficient petroleum degrading bacterium with the ability to produce surface active substances. A diesel oil-degrading bacterial consortium (named SA) was constructed by ZS1 and another oil degrading bacteria by diesel degradation test. Degradation products analysis indicated that SA has a good ability to degrade short chain alkanes, especially n-alkanes (C10-C18). Community structure analysis showed that OTUs of Alcanivorax, Peseudomona, Ruegeria, Pseudophaeobacter, Hyphomonas and Thalassospira on genus level increased after the oil spill and remained stable throughout the recovery period. Most of these enriched microorganisms were related to known alkane and hydrocarbon degraders by the previous study. However, it is the first time to report that Pseudophaeobacter was enriched by using diesel as the sole carbon source. The results also indicated that ZS1 may have a dominant position in competition with indigenous bacteria. Oil pollution has an obvious selective effect on marine microorganisms. Although the oil degradation was promoted after SA injection, the recovery of microbial community structure took a longer time.


Assuntos
Poluição por Petróleo , Petróleo , Alcanos/metabolismo , Bactérias , Biodegradação Ambiental , Hidrocarbonetos/análise , Petróleo/análise , Poluição por Petróleo/análise , Água do Mar/microbiologia
7.
J Neuroinflammation ; 17(1): 335, 2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33161894

RESUMO

BACKGROUND: Perioperative neurocognitive disorders (PNDs) occur frequently after surgery and worsen patient outcome. How C-X-C motif chemokine (CXCL) 13 and its sole receptor CXCR5 contribute to PNDs remains poorly understood. METHODS: A PND model was created in adult male C57BL/6J and CXCR5-/- mice by exploratory laparotomy. Mice were pretreated via intracerebroventricular injection with recombinant CXCL13, short hairpin RNA against CXCL13 or a scrambled control RNA, or ERK inhibitor PD98059. Then surgery was performed to induce PNDs, and animals were assessed in the Barnes maze trial followed by a fear-conditioning test. Expression of CXCL13, CXCR5, and ERK in hippocampus was examined using Western blot, quantitative PCR, and immunohistochemistry. Levels of interleukin-1 beta (IL-1ß) and tumor necrosis factor alpha (TNF-α) in hippocampus were assessed by Western blot. RESULTS: Surgery impaired learning and memory, and it increased expression of CXCL13 and CXCR5 in the hippocampus. CXCL13 knockdown partially reversed the effects of surgery on CXCR5 and cognitive dysfunction. CXCR5 knockout led to similar cognitive outcomes as CXCL13 knockdown, and it repressed surgery-induced activation of ERK and production of IL-1ß and TNF-α in hippocampus. Recombinant CXCL13 induced cognitive deficits and increased the expression of phospho-ERK as well as IL-1ß and TNF-α in hippocampus of wild-type mice, but not CXCR5-/- mice. PD98059 partially blocked CXCL13-induced cognitive dysfunction as well as production of IL-1ß and TNF-α. CONCLUSIONS: CXCL13-induced activation of CXCR5 may contribute to PNDs by triggering ERK-mediated production of pro-inflammatory cytokines in hippocampus.


Assuntos
Quimiocina CXCL13/biossíntese , Hipocampo/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Transtornos Neurocognitivos/metabolismo , Complicações Pós-Operatórias/metabolismo , Receptores CXCR5/biossíntese , Animais , Laparotomia/efeitos adversos , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transtornos Neurocognitivos/etiologia , Complicações Pós-Operatórias/etiologia
8.
J Neuroinflammation ; 17(1): 320, 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33100215

RESUMO

BACKGROUND: Aberrant hippocampal neurogenesis is an important pathological feature of sepsis-associated encephalopathy. In the current study, we examined the potential role of the long noncoding RNA (lncRNA) sex-determining region Y-box 2 (SOX2) overlapping transcript (SOX2OT), a known regulator of adult neurogenesis in sepsis-induced deficits in hippocampal neurogenesis and cognitive function. METHODS: Sepsis was induced in adult C57BL/6 J male mice by cecal ligation and perforation (CLP) surgery. Randomly selected CLP mice were transfected with short interfering RNAs (siRNAs) against SOX2OT or SOX2, or with scrambled control siRNA. Cognitive behavior was tested 8-12 days post-surgery using a Morris water maze. Western blotting and RT-qPCR were used to determine expression of SOX2, Ki67, doublecortin (DCX), nestin, brain lipid-binding protein, and glial fibrillary acidic protein (GFAP) in the hippocampus. The number of bromodeoxyuridine (BrdU)+/DCX+ cells, BrdU+/neuronal nuclei (NeuN)+ neurons, and BrdU+/GFAP+ glial cells in the dentate gyrus were assessed by immunofluorescence. RESULTS: CLP mice showed progressive increases in SOX2OT and SOX2 mRNA levels on days 3, 7, and 14 after CLP surgery, accompanied by impaired cognitive function. Sepsis led to decrease in all neuronal markers in the hippocampus, except GFAP. Immunofluorescence confirmed the decreased numbers of BrdU+/DCX+ cells and BrdU+/NeuN+ neurons, and increased numbers of BrdU+/GFAP+ cells. SOX2OT knockdown partially inhibited the effects of CLP on levels of SOX2 and neuronal markers, neuronal populations in the hippocampus, and cognitive function. SOX2 deficiency recapitulated the effects of SOX2OT knockdown. CONCLUSION: SOX2OT knockdown improves sepsis-induced deficits in hippocampal neurogenesis and cognitive function by downregulating SOX2 in mice. Inhibiting SOX2OT/SOX2 signaling may be effective for treating or preventing neurodegeneration in sepsis-associated encephalopathy.


Assuntos
Cognição/fisiologia , Regulação para Baixo/fisiologia , Hipocampo/metabolismo , Neurogênese/fisiologia , RNA Longo não Codificante/metabolismo , Encefalopatia Associada a Sepse/metabolismo , Animais , Modelos Animais de Doenças , Proteína Duplacortina , Técnicas de Silenciamento de Genes/métodos , Hipocampo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , Encefalopatia Associada a Sepse/genética , Encefalopatia Associada a Sepse/prevenção & controle
9.
Bioresour Technol ; 394: 130200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103752

RESUMO

L-theanine is a natural non-protein amino acid with wide applications. Thus, a high yield of L-theanine production is required on an industrial scale. Herein, an efficient L-theanine-producing strain of Corynebacterium glutamicum was constructed by combining protein and metabolic engineering. Firstly, a γ-glutamylmethylamide synthetase from Paracoccus aminovorans (PaGMAS) was isolated and engineered by computer-aided design, the resulting mutant E179K/N105R improved L-theanine yield by 36.61 %. Subsequently, to increase carbon flux towards L-theanine production, the gene ggt which degrades L-theanine, the gene alaT which participated in L-alanine synthesis, and the gene NCgl1221 which encodes glutamate-exporting protein were deleted. Finally, ppk gene was overexpressed to enhance intracellular ATP production. The reprogramed strain produced 44.12 g/L L-theanine with a yield of 57.11 % and productivity of 1.16 g/L/h, which is the highest L-theanine titer reported by Corynebacterium glutamicum. This study provides an efficient and economical biosynthetic pathway for the industrial production of L-theanine.


Assuntos
Corynebacterium glutamicum , Glutamatos , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Engenharia Metabólica/métodos , Fermentação , Ácido Glutâmico/metabolismo
10.
J Surg Res ; 183(2): 752-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23522481

RESUMO

BACKGROUND: The purpose of this study was to elucidate the possible beneficial effects of adiponectin (APN) on acute lung injury in a rat model of sepsis. METHODS: We subjected male Sprague-Dawley rats to cecal ligation and puncture (CLP) to establish sepsis models. We randomly animals divided into four groups: control (C), model (CLP), preemptive APN administration (APN plus CLP), and delayed APN administration (CLP plus APN). We killed the animals 24 h after CLP and collected blood samples to determine PaO2 and PaCO2. Lung samples were taken for histologic assessment and measurement of myeloperoxidase activity. We measured neutrophil and macrophage count and cytokine production (tumor necrosis factor-α and macrophage inflammatory protein-2) in bronchoalveolar lavage fluid. RESULTS: Histology findings and lung injury score analysis revealed acute lung injury in rats in the CLP group, whereas those in the APN-treated group had mild lung injury. The effects of sepsis on the increasing cell number in bronchoalveolar lavage fluid as well as the wet/dry weight ratio, neutrophil infiltration, and myeloperoxidase activity of lung tissue were significantly attenuated by APN administration. Adiponectin also significantly alleviated hypoxemia and hypercapnia resulting from the development of lung injury. In addition, in APN-treated rats, the levels of pulmonary inflammatory molecule (macrophage inflammatory protein-2) and cytokine (tumor necrosis factor-α) were down-regulated compared with the CLP group. CONCLUSIONS: Adiponectin administration ameliorates acute lung injury in a rat model of sepsis induced by CLP, no matter whether it is administrated before or after the onset of sepsis.


Assuntos
Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/prevenção & controle , Adiponectina/uso terapêutico , Ceco/lesões , Sepse/complicações , Lesão Pulmonar Aguda/metabolismo , Adiponectina/farmacologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Ligadura/efeitos adversos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/patologia , Masculino , Neutrófilos/patologia , Peroxidase/metabolismo , Punções/efeitos adversos , Ratos , Ratos Sprague-Dawley , Sepse/etiologia
11.
J Proteomics ; 270: 104736, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36174953

RESUMO

Seed longevity is important for the maintenance of seed nutritional quality, vigor, and germination potential during storage. Sacred lotus is known as one of the longest living seeds in the world and their ability to maintain longevity has been widely investigated. In this study, a suitable controlled deterioration treatment (CDT) method was first established to evaluate the vigor loss of lotus plumule (LP), and then the Tandem Mass Tags (TMT)-based proteomic analysis was performed on LP from the CDT-treated seed to quantitatively and qualitatively analyze the protein profile dynamic. In total, 4002 proteins were successfully quantified, of them, 558 differently accumulated proteins (DAPs) were identified. Protein processing and RNA-related proteins were found more easily to be affected by CDT, which may directly result in seed vigor loss. Meanwhile, CDT resulted in remarkable up-regulation of numerous proteins related to antioxidation, photosynthesis, RNA and DNA stability, starch and sucrose mobilization, and cell membrane and wall stability, which potentially played key roles in maintaining the lotus seed vigor under CDT. Histological and physiological analyses were also performed to verify some proteome results. This study provided both fundamental data and new insights to further uncover the secret of lotus seed longevity. SIGNIFICANCE: Seed aging affects the seed quality and can result in direct economic losses. The exceptional longevity of sacred lotus seed has attracted extensive attention. In this study, an optimized CDT method was used to mimic the natural aging process of sacred lotus seed, and based on TMT-based quantitative proteomic analysis on the LP profile of CDT-treated seeds, a series of differentially accumulation of specific proteins (DEPs) were revealed related to CDT resistance. Correspondingly, the physiological state and histological structure of the LP along with the CDT were detected to verify the proteome data. This study provided comprehensive information for the molecular basis of lotus seed aging analysis and facilitate to screen seed longevity related proteins for other plant species.


Assuntos
Nelumbo , Nelumbo/genética , Nelumbo/metabolismo , Proteômica/métodos , Proteoma/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , RNA
12.
Biotechnol Adv ; 69: 108260, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37739275

RESUMO

L-methionine is an essential amino acid with versatile applications in food, feed, cosmetics and pharmaceuticals. At present, the production of L-methionine mainly relies on chemical synthesis, which conflicts with the concern over serious environmental problems and sustainable development goals. In recent years, microbial production of natural products has been amply rewarded with the emergence and rapid development of system metabolic engineering. However, efficient L-methionine production by microbial fermentation remains a great challenge due to its complicated biosynthetic pathway and strict regulatory mechanism. Additionally, the engineered production of L-methionine precursors, L-homoserine, O-succinyl-L-homoserine (OSH) and O-acetyl-L-homoserine (OAH), has also received widespread attention because they can be catalyzed to L-methionine via a high-efficiently enzymatic reaction in vitro, which is also a promising alternative to chemical route. This review provides a comprehensive overview on the recent advances in the microbial production of L-methionine and its precursors, highlighting the challenges and potential solutions for developing L-methionine microbial cell factories from the perspective of systems metabolic engineering, aiming to offer guidance for future engineering.


Assuntos
Engenharia Metabólica , Metionina , Metionina/metabolismo , Homosserina/metabolismo , Vias Biossintéticas , Fermentação
13.
J Fungi (Basel) ; 9(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37504723

RESUMO

Cysteine-rich secretory proteins (C), antigen 5 (A), and pathogenesis-related 1 proteins (P) comprise widespread CAP superfamily proteins, which have been proven to be novel virulence factors of mammalian pathogenic fungi and some plant pathogens. Despite this, the identification and function of CAP proteins in more species of plant pathogens still need to be studied. This work presents the identification and functional analysis of CAP superfamily proteins from Puccinia striiformis f. sp. tritici (Pst), an important fungal pathogen that causes wheat stripe rust on wheat worldwide. A total of six CAP genes were identified in the Pst genome, designated as PsCAP1-PsCAP6. Five PsCAP proteins, including PsCAP1, PsCAP2, PsCAP3, PsCAP4, and PsCAP5, have N-terminal signal peptides secreted with the yeast signal sequence trap assay. Single-nucleotide polymorphism (SNP) analysis indicated that they showed a low level of intraspecies polymorphism. The expression abundance of PsCAP genes at different Pst infection stages was detected by RT-qPCR, and most of them were highly expressed during Pst infection on wheat and also Pst sexual reproduction on barberry (Berberis shensiana). Noticeably, the silencing of these six PsCAP genes by BSMV-mediated HIGS indicated that PsCAP1, PsCAP4, and PsCAP5 contribute significantly to Pst infection in wheat. These results indicate that PsCAP proteins may act as virulence factors during Pst infection, which also provides insights into Pst pathogenicity.

14.
Bioresour Technol ; 389: 129828, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806363

RESUMO

L-Homoserine is an important amino acid as a precursor in synthesizing many valuable products. However, the low productivity caused by slow L-homoserine production during active cell growth in fermentation hinders its potential applications. In this study, strategies of engineering the synthetic pathway combined with regulating cell division were employed in an L-homoserine-producing Escherichia coli strain for efficiently biomanufacturing L-homoserine. First, the flux-control genes in the L-homoserine degradation pathway were omitted to redistribute carbon flux. To drive more carbon flux into L-homoserine production, the phosphoenolpyruvate-pyruvate-oxaloacetate loop was redrawn. Subsequently, the cell division was engineered by using the self-regulated promoters to coordinate cell growth and L-homoserine production. The ultimate strain HOM23 produced 101.31 g/L L-homoserine with a productivity of 1.91 g/L/h, which presented the highest L-homoserine titer and productivity to date from plasmid-free strains. The strategies used in this study could be applied to constructing cell factories for producing other L-aspartate derivatives.


Assuntos
Escherichia coli , Homosserina , Escherichia coli/genética , Escherichia coli/metabolismo , Homosserina/genética , Homosserina/metabolismo , Engenharia Metabólica , Fermentação , Divisão Celular
15.
Macromol Rapid Commun ; 33(8): 693-7, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22354753

RESUMO

A water-soluble polycarbonate with dimethylamino pendant groups, poly(2-dimethylaminotrimethylene carbonate) (PDMATC), is synthesized and characterized. First, the six-membered carbonate monomer, 2-dimethylaminotrimethylene carbonate (DMATC), is prepared via the cyclization reaction of 2-(dimethylamino)propane-1,3-diol with triphosgene in the presence of triethylamine. Although the attempted ring-opening polymerization (ROP) of DMATC with Sn(Oct)(2) as a catalyst fails, the ROP of DMATC is successfully carried out with Novozym-435 as a catalyst to give water-soluble aliphatic polycarbonate PDMATC with low cytotoxicity and good degradability.


Assuntos
Lipase/metabolismo , Cimento de Policarboxilato/química , Poliésteres/síntese química , Água/química , Animais , Biocatálise , Células COS , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Ciclização , Células HeLa , Humanos , Poliésteres/química , Poliésteres/toxicidade , Polimerização , Propanolaminas , Propilenoglicóis/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-36231381

RESUMO

Land resources are foundational for human survival and development. In contrast, land use/land cover (LULC) dynamics drive considerable changes in ecosystem services. Recently, China witnessed a new stage of rapid urbanization. Therefore, investigating the relationships between ecosystem services value (ESV) and LULC in these areas is highly relevant. Based on the data of land use and socioeconomic development in Shanghai from 2000 to 2020, we adopted a land use/land cover dynamics analysis method and established the ESV per unit area at the city scale, discussed the impact of LULC on ESV spatially and quantitatively, and tested the research process based on the sensitivity analysis of the ESV coefficient. The results show that from 2000 to 2020, the LULC pattern in Shanghai rapidly changed. In particular, the area of cultivated land has shrunk by 123.96 thousand hm2, while the construction land has expanded by 141.26 thousand hm2, which has led to a decline in ESV of the entire city (especially regarding hydrological adjustment and biodiversity). Nevertheless, although the area of trench and lakes only occupies 1.67-3.16% of the total area of land, its ecological value accounts for an astonishing 23.80-50.70% of the total ESV. At the district level, the primary decline in eco-system services value was noted in the Chongming District in the north and Pudong New Area in the east of Shanghai. However, due to the overall planning of the city and the advantages of its resource endowment, Qingpu District and its surrounding areas in western Shanghai have witnessed improvements in terms of the values of hydrological adjustment, water supply, and environmental purification. This study presents a deeper and more comprehensive understanding of issues regarding ESV in rapidly urbanized areas, thereby providing an important reference for decision-makers regarding the rational layout of cities, sustainable use of land, and management of natural ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Cidades , Humanos , Urbanização
17.
Bioresour Technol ; 364: 128054, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36184013

RESUMO

l-arginine is a semi-essential amino acid that is broadly used as food additives and pharmaceutical intermediates. The synthesis of l-arginine is restricted by complex metabolic mechanisms and suboptimal fermentation conditions. Initially, a mutant strain that accumulated 19.4 g/L l-arginine was generated by random mutagenesis. Subsequently, a mutation of the repressor protein (argRG159D) in the l-arginine operon and glutamate synthase (gltD) with 532-fold upregulation were identified to be vital for l-arginine production by multi-omic analysis. Systematic metabolic engineering was used to modify the strain, which included interfering with α-ketoglutarate dehydrogenase complex (ODHC) activity by knocking out serine/threonine-protein kinase (pknG), enhancing the expression of multiple key enzymes in the l-arginine synthesis pathway, and increasing the availability of intracellular cofactor (NADPH) and energy (ATP). Finally, C. glutamicum ARG12 produced 71.3 g/L l-arginine, with a yield of 0.43 g/g glucose by fermentation optimization. This study provides new ideas to boost l-arginine production.

18.
Front Oncol ; 12: 829798, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35578660

RESUMO

Breast cancer complicated with diabetes mellitus (DM) is a common disease. To evaluate the effect of preexisting DM on breast cancer progression without drug interference, we used a streptozotocin (STZ)-induced type 2 diabetes mellitus BALB/c mouse model. We found that 4T1 breast cancer complicated with DM decreased the mouse survival time compared with 4T1-bearing mice. The diversity of gut microbiome was affected by DM. The infiltration of mucosal-associated invariant T cell (MAIT), CD8+ T cell, and CD4+ T cell in the tumor was significantly decreased in the DM-4T1 group compared with the 4T1 group. The transcriptome data of tumor tissues indicated that the expressions of inflammatory C-C chemokine- and metabolism-related genes were greatly changed. The abnormal expression of these genes may be related with the decreased T-cell infiltration in DM-4T1. In conclusion, the gut microbiome and tumor microenvironment of diabetic breast cancer patients have unique features. The effect of diabetes on breast cancer should be considered in the treatment for diabetic breast cancer patients.

19.
Front Pharmacol ; 13: 889181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694271

RESUMO

Purpose: This study aimed to investigate the relationship between gut microbiota (GM) and serum metabolism using antineoplastic Fufangchangtai (FFCT) as the model prescription in the treatment of colorectal cancer (CRC). Methods: Tumor-bearing mice and normal mice were administered different doses of FFCT. The tumor volume of tumor-bearing mice was observed. The levels of CD4+ and CD8+ T cells in the blood, spleen, and tumor of mice were determined using a flow cytometer. The bacterial microbiota in stool samples from mice and the serum metabolomics of FFCT-treated mice and fecal microbiota transplantation mice were detected using 16s RNA sequencing and liquid chromatography-mass spectrometry (LC/MS), respectively. Results: The tumor volume of mice showed no significant decrease after FFCT intervention. The levels of CD4+ and CD8+T lymphocytes showed a significant increase under the intervention of FFCT. GM of colorectal tumor-bearing mice and healthy mice were determined, and the diversity and abundance of Firmicutes, Deferribacteres, Bacteroidetes, and Proteobacteria were significantly different between the two groups. Furthermore, we found that the levels of matrine, isogingerenone B, and armillaripin were significantly decreased in tumor-bearing mice after FFCT intervention, indicating that the tumor-induced dysbiosis of gut bacteria may affect the absorption and metabolism of FFCT. Under the intervention of FFCT, serum metabolism of mice transplanted with feces from CRC patients showed less metabolites related to FFCT than that from healthy people, indicating that GM could be a single factor affecting the metabolism of FFCT. Furthermore, we found that different doses of FFCT-treated mice had higher abundance of Roseburia, Turicibacter, and Flexispira than that in the non-intervention control group. Firmicutes and Bacteroidetes in FFCT-treated groups showed a similar trend compared to the healthy group, indicating that FFCT might correct the intestinal microenvironment by modulating gut microbiota in colorectal tumor-bearing mice. Conclusion: The dysbiosis of GM in tumor-bearing mice reduced the serum metabolites related to FFCT, and FFCT could correct the disordered GM of colorectal tumor-bearing mice to exert efficacy.

20.
Biomaterials ; 284: 121523, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35462306

RESUMO

Tumor cells intensively engage in metabolic reprogramming for enhancing the availability of glycolytic metabolites and support cell proliferation. As the most important rate-limiting enzyme in aerobic glycolysis, activating the pyruvate kinase muscle isoform 2 (PKM2) from dimers to tetramers has become a key tumor chemotherapy method to control glucose metabolism. Herein, we developed a glycopeptide-based PKM2 nano-activator, which could induce the tetramerization of PKM2 based on serine bonding to Domain C of PKM2. The bound and trapped PKM2 tetramers significantly hindered glycolytic intermediates, prevented the nucleus translocation of dimeric PKM2, and ultimately inhibited the proliferation, chemoresistance and metastasis of tumor. The glycopeptide assembled into nanoparticles under aqueous conditions and in the circulation, which in situ transformed into PKM2 nano-activator with nanofibrillar structure after specifically activated by O-GlcNAcase recognition upregulated in a wide range of human tumors. Moreover, the glycopeptide-based PKM2 nano-activator successfully accumulated at the tumor sites and boosted the chemo-drug sensitivity against prostate and breast cancers. Attributed to these intriguing results, the newly developed glycopeptide-based PKM2 nano-activator can be envisioned a promising candidate for the treatment of tumors by switching catabolic pathways.


Assuntos
Neoplasias da Mama , Piruvato Quinase , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Glicólise , Glicopeptídeos/metabolismo , Humanos , Masculino , Músculos/metabolismo , Isoformas de Proteínas/metabolismo , Piruvato Quinase/metabolismo
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