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1.
Medicina (Kaunas) ; 58(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36295504

RESUMO

Background and Objectives: To assess the efficacy and safety of hepatic arterial infusion chemotherapy (HAIC) with oxaliplatin plus raltitrexed (HAICROX) as an alternative treatment option for advanced hepatocellular carcinoma (HCC) patients who are ineligible for, or failed, the transarterial chemoembolization (TACE) treatment. Materials and Methods: From July 2020 to November 2021, a total of 35 HCC patients were enrolled and received HAIC with oxaliplatin plus raltitrexed. The overall survival (OS) and time to progression (TTP) were primary and secondary endpoints, respectively. The tumor response was assessed by the modified response evaluation criteria in solid tumors (mRECIST), and the adverse events were investigated using the common terminology criteria for adverse events version 5.0 (CTCAE 5.0). Results: The median OS and TTP were 10 months (95% confidence interval (CI): 5.5-14.6) and 3.5 months (95% CI: 2.3-4.7), respectively. By means of multivariate analysis, anti-programmed cell death protein 1 (anti-PD-1) immunotherapy was found to be an independent prognostic factor for better survival. No patients experienced toxicity-related death. Thrombocytopenia, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) elevation were the most common toxicities. No grade 3 or higher adverse events related to HAICROX were observed. Conclusion: HAICROX showed valuable efficacy and tolerable toxicity in advanced HCC patients who progressed on TACE or were ineligible for TACE. HAICROX is a promising treatment for advanced-stage HCC patients with TACE failure or ineligibility.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Oxaliplatina/uso terapêutico , Quimioembolização Terapêutica/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Alanina Transaminase , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aspartato Aminotransferases , Resultado do Tratamento
2.
Medicina (Kaunas) ; 58(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36013483

RESUMO

Background and Objectives: The recurrence outcome in patients who underwent microwave ablation (MWA) with or without transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) within Milan criteria remains unclear. The aim of this retrospective study was to identify the predictive factors of recurrence in these patients. Materials and Methods: From May 2018 to April 2021, 66 patients with HCC within Milan criteria were enrolled. Local tumor progression (LTP) and recurrence-free survival (RFS) were evaluated. Univariate and multivariate analyses were used to evaluate the risk factors of recurrence. The propensity score analysis was conducted to reduce potential confounding bias. Results: During the median follow-up of 25.07 months (95% confidence interval [CI], 21.85, 28.28), the median time to LTP and RFS were 20.10 (95%CI, 14.67, 25.53) and 13.03 (95%CI, 6.36, 19.70) months. No group difference (MWA vs. MWA + TACE) was found in 1-year cumulative LTP (p = 0.575) and RFS (p = 0.515), but meaningful significant differences were found in two-year recurrence (LTP, p = 0.007 and RFS, p = 0.037). Univariate and multivariate analyses revealed that treatment received before ablation was an independent risk factor of LTP (hazard ratio [HR] 4.37, 95%CI, 1.44, 13.32) and RFS (HR 3.41, 95%CI, 1.49, 7.81). Conclusions: The LTP and RFS in the MWA group were similar to that in the MWA combined with TACE. For HCC within Milan criteria, both groups preferentially selected MWA. More endeavor and rigorous surveillance should be taken to relapse prevention, in patients who have received previous treatment.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento
3.
Cancers (Basel) ; 14(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35954373

RESUMO

Transarterial chemoembolization (TACE) combined with tyrosine kinase inhibitors (TKIs) is the mainstay treatment for unresectable hepatocellular carcinoma (uHCC). However, studies investigating different combinations of agents have shown inconsistent results. Here, we used network meta-analysis (NMA) to compare different agents across 41 studies (36 cohort studies and five RCTs) in 11,540 patients. Multiple RCTs and cohort studies were searched to evaluate TACE combined with different TKIs. Outcomes of interest included overall survival (OS), progression-free survival (PFS), and tumor response. NMA used a random-effects consistency model to pool evidence from direct and indirect comparisons. Hazard ratio (HR) and relative risks (RR) with 95% confidence intervals (CI) were analyzed. Further, heterogeneity and publication bias analyses were performed and agents were ranked. TACE plus lenvatinib provided the maximal OS (Rank probability: 0.7559), PFS (Rank probability: 0.8595), CR (Rank probability: 0.4179), and DCR (Rank probability: 0.3857). TACE plus anlotinib demonstrated the highest PR (p = 0.62649) and ORR (p = 0.51158). SD was more often associated with TACE plus sorafenib (Rank probability: 0.601685). TACE plus lenvatinib provides optimal treatment for uHCC based on the highest ranking of OS, PFS, and DCR rates. However, given the lack of statistically significant OS benefit, shared decision making should include other TKIs as acceptable alternatives.

4.
Curr Oncol ; 29(2): 423-432, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35200538

RESUMO

The prognostic value of the tumor growth rate (TGR) in huge hepatocellular carcinoma (HHCC) patients treated with transcatheter arterial chemoembolization (TACE) as an initial treatment remains unclear. This two-center retrospective study was conducted in 97 patients suffering from HHCC. Demographic characteristics, oncology characteristics, and some serological markers were collected for analysis. The TGR was significantly linear and associated with the risk of death when applied to restricted cubic splines. The optimal cut-off value of TGR was -8.6%/month, and patients were divided into two groups according to TGR. Kaplan-Meier analysis showed that the high-TGR group had a poorer prognosis. TGR (hazard ratio (HR), 2.06; 95% confidence interval (CI), 1.23-3.43; p = 0.006), presence of portal vein tumor thrombus (PVTT) (HR, 1.93; 95% CI, 1.13-3.27; p = 0.016), and subsequent combination therapy (HR, 0.59; 95% CI, 0.35-0.99; p = 0.047) were independent predictors of OS in the multivariate analysis. The model with TGR was superior to the model without TGR in the DCA analysis. Patients who underwent subsequent combination therapy showed a longer survival in the high-TGR group. This study demonstrated that higher TGR was associated with a worse prognosis in patients with HHCC. These findings will distinguish patients who demand more personalized combination therapy and rigorous surveillance.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/terapia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
5.
Front Genet ; 12: 789296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925465

RESUMO

Pyroptosis is a novel kind of cellular necrosis and shown to be involved in cancer progression. However, the diverse expression, prognosis and associations with immune status of pyroptosis-related genes in Hepatocellular carcinoma (HCC) have yet to be analyzed. Herein, the expression profiles and corresponding clinical characteristics of HCC samples were collected from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Then a pyroptosis-related gene signature was built by applying the least absolute shrinkage and selection operator (LASSO) Cox regression model from the TCGA cohort, while the GEO datasets were applied for verification. Twenty-four pyroptosis-related genes were found to be differentially expressed between HCC and normal samples. A five pyroptosis-related gene signature (GSDME, CASP8, SCAF11, NOD2, CASP6) was constructed according to LASSO Cox regression model. Patients in the low-risk group had better survival rates than those in the high-risk group. The risk score was proved to be an independent prognostic factor for overall survival (OS). The risk score correlated with immune infiltrations and immunotherapy responses. GSEA indicated that endocytosis, ubiquitin mediated proteolysis and regulation of autophagy were enriched in the high-risk group, while drug metabolism cytochrome P450 and tryptophan metabolism were enriched in the low-risk group. In conclusion, our pyroptosis-related gene signature can be used for survival prediction and may also predict the response of immunotherapy.

6.
Front Oncol ; 11: 709278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540675

RESUMO

BACKGROUND: It is controversial whether adjuvant treatment could be recommended for hepatocellular carcinoma (HCC) after curative hepatectomy. Thus, we performed a network meta-analysis (NMA) to assess adjuvant treatment's benefit and determine the optimal adjuvant regimen. METHODS: We systematically searched PubMed, Embase, and Cochrane Library for randomized controlled trials comparing adjuvant therapy versus no active treatment after curative hepatectomy among patients with HCC. Pooled data on recurrence and overall survival (OS) were analyzed within pairwise meta-analysis and NMA. RESULTS: Twenty-three eligible trials (3,940 patients) reporting eight treatments were included. The direct meta-analysis showed that adjuvant therapy prevented the recurrence (OR = 0.65; 95% CI: 0.55, 0.77; P = 0.177; I2 = 21.7%) and contributed to OS (HR = 0.63; 95% CI: 0.54, 0.73; P = 0.087; I2 = 31.1%) in comparison to the observation. In the NMA, internal radiotherapy (IRT; OR = 0.55; 95% CI: 0.39, 0.77; SUCRA = 87.7%) followed by hepatic artery infusion chemotherapy (HAIC; OR = 0.6; 95% CI: 0.36, 0.97; SUCRA = 77.8%), and HAIC (HR = 0.44; 95% CI: 0.21, 0.87; SUCRA = 82.6%) followed by IRT (HR 0.54; 95% CI:0.36, 0.81; SUCRA = 69.7%) were ranked superior to other treatments in terms of preventing recurrence and providing survival benefit, respectively. CONCLUSIONS: The addition of adjuvant therapy lowers the risk of recurrence and provide survival benefit after surgical resection for HCC. HAIC and IRT are likely to be the two most effective adjuvant regimens. SYSTEMATIC REVIEW REGISTRATION: https://inplasy.com/inplasy-2020-11-0039/.

7.
Artigo em Chinês | MEDLINE | ID: mdl-32148224

RESUMO

OBJECTIVE: To investigate the molecule mechanism of nuclear translocation of hypoxia-inducible factor-1α (HIF-1α) in influenza A (H1N1) virus infected-alveolar epithelial cells. METHODS: Human lung adenocarcinoma epithelial cells (A549 cells) were cultured in vitro, and cells in logarithmic growth phase were selected for experiments. (1) Experiment 1: the A549 cell model with H1N1 virus infection was established by using H1N1 virus infected cells with multiplicity of infection (MOI) 1.0 for 24 hours (H1N1 virus infection group), and the blank control group was set up. Importin 4 and Importin 7 protein expressions were detected by Western Blot to investigate whether HIF-1α nuclear translocation depended on Importin 4 or Importin 7. (2) Experiment 2: the A549 cells were infected with H1N1 virus under different MOI (0, 0.1, 0.5, 1.0, 2.0, 4.0) for 24 hours. Then the A549 cells were infected with H1N1 virus (MOI 1.0) for different time (0, 3, 6, 12, 18, 24, 36 hours). The septin 9 isoform 1 (SEPT9_i1) mRNA expression was detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR) to investigate the effect of different MOI and infection time on the expression of SEPT9_i1. (3) Experiment 3: a cell model with SEPT9_i1 silencing was established by transfection of small interfering RNA (siRNA) for 24 hours (siRNA-SEPT9_i1 group), and the blank control group and blank vector control group (siControl group) were set up. Then the cells in the three groups were infected with H1N1 virus (MOI 1.0) for 24 hours after 24-hour transfection, and the SEPT9_i1 mRNA expression was detected by real-time fluorescence quantitative RT-PCR to investigate the interference efficiency of siRNA-SEPT9_i1. (4) Experiment 4: the cells were divided into siControl group and siRNA-SEPT9_i1 group. The transfection methods of two groups was as the same as experiment 3,and then the cells were infected with H1N1 virus (MOI 1.0) after 24-hour transfection. The distribution of HIF-1α was detected by immunofluorescence at 24 hours after infection. The M gene expression of virus was detected by real-time fluorescence quantitative RT-PCR at 6, 12, 24, 36, 48 hours after infection. The effects of SEPT9_i1 on HIF-1α translocation and virus replication were explored. (5) Experiment 5: the cells were divided into blank control group (complete medium), SP600125 group [100 µmol/L c-Jun N-terminal kinase (JNK) signaling pathway inhibitor SP600125 for 2 hours], H1N1 virus infection group (H1N1 virus of MOI 1.0 for 24 hours), H1N1 virus+SP600125 group (pretreated with 100 µmol/L SP600125 for 2 hours before 24-hour H1N1 virus infection). Real-time fluorescence quantitative RT-PCR was used to detect the expressions of SEPT_i1 mRNA and viral M gene to investigate the effect of JNK signaling pathway on SEPT9_i1 expression and virus replication. RESULTS: (1) Experiment 1: compared with the blank control group, the protein expressions of Importin 4 and Importin 7 in the H1N1 virus infection group had no significant changes [Importin 4 protein (Importin 4/GAPDH): 1.08±0.03 vs. 1.05±0.03, Importin 7 protein (Importin 7/GAPDH): 0.87±0.11 vs. 0.78±0.03, both P > 0.05]. These indicated that the HIF-1α nuclear translocation in A549 cells might not be independent of Importin 4 and Importin 7 during H1N1 virus infection. (2) Experiment 2: the SEPT9_i1 mRNA expression in A549 cells was increased with the increase in MOI and infection time of H1N1 virus, and peaked at MOI 2.0 or 18 hours after infection, and the differences were statistically significant as compared with MOI 0 or 0 hour after infection (2-ΔΔCT: 1.39±0.05 vs. 1.00±0.00 at MOI 2.0, 1.47±0.04 vs. 1.00±0.00 at 18 hours, both P < 0.01). This indicated that the SEPT9_i1 expression in A549 cells was related to the MOI and the infection time during H1N1 virus infection. (3) Experiment 3: compared with the blank control group, the SEPT9_i1 mRNA expression in A549 cells was significantly decreased in the siRNA-SEPT9_i1 group (2-ΔΔCT: 0.38±0.11 vs. 1.00±0.00, P < 0.01), and there was no significant difference between the siControl group and blank control group (2-ΔΔCT: 1.03±0.16 vs. 1.00±0.00, P > 0.05). This indicated that SEPT9_i1 silence could inhibit the expression of SEPT9_i1 mRNA in H1N1 virus-infected A549 cells. (4) Experiment 4: HIF-1α nuclear translocation in the H1N1 virus-infected A549 cells in the siRNA-SEPT9_i1 group was significantly reduced as compared with the siControl group. The virus M gene expression after H1N1 virus infection in the siControl group was gradually increased, and peaked at 48 hours. The expression of virus M gene in A549 cells in the siRNA-SEPT9_i1 group was significantly down-regulated, and showed a statistically significant difference at 48 hours as compared with the siControl group (2-ΔΔCT: 3.47±0.66 vs. 8.17±0.38, P < 0.05). This indicated that HIF-1α nuclear translocation and virus replication in H1N1 virus-infected A549 cells were inhibited after silencing SEPT9_i1. (5) Experiment 5: the expressions of SEPT9_i1 mRNA and virus M gene in A549 cells in the H1N1 virus infection group were significantly higher than those in the blank control group. However, the expressions of SEPT9_i1 mRNA and viral M gene in A549 cells in the H1N1 virus+SP600125 group were significantly lower than those in the H1N1 virus infection group (2-ΔΔCT: SEPT9_i1 mRNA was 0.12±0.10 vs. 1.53±0.14, viral M gene was 2.13±0.10 vs. 4.66±0.14, both P < 0.05). There was no significant difference in above indicators between the SP600125 group and the blank control group. This indicated that the JNK signaling pathway could regulate the expression of SEPT9_i1 in A549 cells during H1N1 virus infection, and the JNK signaling pathway inhibition could down-regulate the expression of SEPT9_i1 and inhibit virus replication. CONCLUSIONS: The H1N1 virus regulates the expression of SEPT9_i1 by activating the JNK signaling pathway, thus increase HIF-1α transport efficiency and H1N1 replication.


Assuntos
Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Vírus da Influenza A Subtipo H1N1 , Células A549 , Transporte Ativo do Núcleo Celular , Humanos , Influenza Humana , Carioferinas/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Membrana Transportadoras/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Septinas/metabolismo
8.
J Cell Mol Med ; 21(12): 3529-3539, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28699703

RESUMO

Irreversible pulmonary fibrosis induced by paraquat (PQ) poisoning is the major cause of death in patients with PQ poisoning. The epithelial-mesenchymal transition (EMT) is postulated to be one of the main mechanisms of pulmonary fibrosis. Here, we investigated the role of miR-210 in PQ-induced EMT and its relationship with hypoxia-inducible factor-1α (HIF-1α). Western blotting, immunofluorescence, immunoprecipitation and other methods were used in this study. We found that miR-210 expression was significantly increased after PQ poisoning, and it may be regulated by HIF-1α. Overexpression of miR-210 further increased the HIF-1α protein level and promoted EMT. Moreover, miR-210 knock-down reduced the HIF-1α protein level and decreased the degree of EMT. Runt-related transcription factor-3 (RUNX3), a direct target of miR-210, was inhibited by miR-210 in response to PQ poisoning. RUNX3 increased the hydroxylation ability of prolyl hydroxylase domain-containing protein 2 (PHD2), a key enzyme that promotes HIF-1α degradation. PHD2 immunoprecipitated with RUNX3 and its level changed similarly to that of RUNX3. The expression of the HIF-1α protein was significantly reduced when RUNX3 was overexpressed. HIF-1α protein levels were markedly increased when RUNX3 was silenced. Based on these results, a positive feedback loop may exist between miR-210 and HIF-1α. The mechanism may function through miR-210-mediated repression of RUNX3, which further decreases the hydroxylation activity of PHD2, enhances the stability of HIF-1α, and promotes PQ-induced EMT, aggravating the progression of pulmonary fibrosis. This study further elucidates the mechanism of PQ-induced pulmonary fibrosis and may provide a new perspective for the future development of therapies.


Assuntos
Subunidade alfa 3 de Fator de Ligação ao Core/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Retroalimentação Fisiológica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/genética , Paraquat/intoxicação , Fibrose Pulmonar/genética , Células A549 , Animais , Linhagem Celular , Subunidade alfa 3 de Fator de Ligação ao Core/antagonistas & inibidores , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia , Masculino , MicroRNAs/metabolismo , Pró-Colágeno-Prolina Dioxigenase/genética , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Estabilidade Proteica , Proteólise , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
9.
Emerg Microbes Infect ; 6(5): e39, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28536432

RESUMO

Infection with the influenza A (H1N1) virus is a major challenge for public health because it can cause severe morbidity and even mortality in humans. The over-secretion of inflammatory cytokines (cytokine storm) is considered to be a key contributor to the severe pneumonia caused by H1N1 infection. It has been reported that hypoxia-inducible factor 1-alpha (HIF-1α) is associated with the production of proinflammatory molecules, but whether HIF-1α participates in the acute inflammatory responses against H1N1 infection is still unclear. To investigate the role of HIF-1α in H1N1 infection, the expression and nuclear translocation of HIF-1α in A549 and THP-1 cell lines infected with H1N1 virus were observed. The results showed that without altering the intracellular mRNA or protein expression of HIF-1α, H1N1 infection only induced nuclear translocation of HIF-1α under normal oxygen concentrations. The use of 2-methoxyestradiol (2ME2), a HIF-1α inhibitor that blocks HIF-1α nuclear accumulation, in H1N1-infected cells decreased the mRNA and protein expression of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 and increased the levels of IL-10. In contrast, H1N1-infected cells under hypoxic conditions had increased HIF-1α nuclear accumulation, increased expression of TNF-α and IL-6 and decreased levels of IL-10. In conclusion, our data implied that in vitro H1N1 infection induced nuclear translocation of HIF-1α without altering the expression of HIF-1α, which may promote the secretion of proinflammatory cytokines during H1N1 infection.


Assuntos
Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Citocinas/biossíntese , Citocinas/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Vírus da Influenza A Subtipo H1N1/imunologia , 2-Metoxiestradiol , Células A549 , Hipóxia Celular , Estradiol/análogos & derivados , Estradiol/farmacologia , Regulação da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Inflamação , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Monócitos/imunologia , Monócitos/virologia , Oxigênio/metabolismo , RNA Mensageiro , Células THP-1 , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
10.
Biotechnol Appl Biochem ; 60(6): 557-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23586646

RESUMO

2,3-Butanediol (2,3-BD) is a major by-product of 1,3-propanediol (1,3-PDO) fermentation by Klebsiella pneumoniae ZG25. It not only consumes large amounts of its carbon source and nicotinamide adenine dinucleotide to diminish synthesis of 1,3-PDO, but also serves as an obstacle to high-purity 1,3-PDO in downstream processes. To decrease the formation of 2,3-BD and make an intrinsic improvement in 1,3-PDO production, the budC gene in K. pneumoniae, coding 2,3-BD dehydrogenase, which is a key gene of the 2,3-BD pathway, was successfully knocked out using the Red recombination system described in this paper. The results of the mutant fed-batch fermentation showed that the 1,3-PDO concentration, productivity per cell dry weight, and conversion rate increased to 880 mmol L(-1) , 22.0 mmol L(-1) h(-1) , and 0.700 mol mol(-1) , respectively, increasing by 10%, 15%, and 11% compared with the parent strain. Meanwhile, 2,3-BD was still found in fermentation broth with the 2,3-BD metabolic pathway blocked, which implies that K. pneumoniae possesses a pathway of the 2,3-BD cycle as a replenishment pathway.


Assuntos
Proteínas de Bactérias/genética , Técnicas de Inativação de Genes , Glicerol/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Propilenoglicóis/metabolismo , Técnicas de Cultura Celular por Lotes , Biotransformação , Fermentação , Klebsiella pneumoniae/citologia , Mutação
11.
Sheng Wu Gong Cheng Xue Bao ; 29(9): 1290-300, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24409692

RESUMO

2,3-butanediol (2,3-BD) is a major byproduct of 1,3-propandediol (1,3-PDO) fermentation by Klebsiella pneumoniae. To decrease the formation of 2,3-BD, the budC and budA gene, coding two key enzymes of 2,3-BD synthetic pathway in K. pneumoniae, were knocked out using Red recombination technology. The growth of the two mutants were suppressed in different level. The budC deficient strain fermentation results showed that 1,3-PDO concentration increased to 110% and 2,3-butanediol concentration dropped to 70% of the parent strain. However, the budA deficient strain did not produce 1,3-PDO and 2,3-BD, and the final titer of lactic acid, succinic acid, ethanol and acetic acid increased remarkably compared with the parent strain. Further analysis of budC deficient strain fermentation inferred that K. pneumoniae possessed the 2,3-BD cycle as a replenishment pathway. The consequence provided a new evidence for reforming low-byproduct K. pneumoniae.


Assuntos
Butileno Glicóis/metabolismo , Carboxiliases/genética , Técnicas de Inativação de Genes , Klebsiella pneumoniae/genética , Propilenoglicóis/metabolismo , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Proteínas de Bactérias/genética , Glicerol/metabolismo , Klebsiella pneumoniae/metabolismo , Mutação
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