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1.
J Nanosci Nanotechnol ; 20(3): 1709-1714, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492334

RESUMO

In this article, nano-NbC particles toughened Si3N4-based ceramics were prepared by injection moulding and their mechanical properties along with toughening mechanism were studied. An increase of nano-NbC content, gradually homogenizes microstructure of the Si3N4-based ceramics along with increase in its density. However, the fracture toughness and flexural strength first increases and then decreases. The Si3N4-based ceramics demonstrate good comprehensive properties at the 15 wt% nano-NbC content and sintering temperature of 1550 °C (where the density is 85.3%, the flexural strength is 845 MPa, and the fracture toughness is 9.3 MPa·m1/2), Backscattered electron imaging shows that nano-NbC particles can be well dispersed in the Si3N4 ceramic matrix by injection moulding and ceramics are toughened by crack deflection and microcracking effects. It was also found that increasing sintering temperature makes the ß-Si3N4 grain distribution more uniform by reducing the porosity.

2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1367-1373, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607285

RESUMO

OBJECTIVE: To study the effects of miR-221 on the biological activity of childhood acute lymphoblastic leukemia cells and its mechanism. METHODS: Bone marrow mononuclear cells (BMNC) were isolated from bone marrow samples of ALL children diagnosed in our hospital from May 2018 to November 2018. The cells were divided into control group, miR-221-NC group and miR-221 group. After transfection according to the instructions of Lipofectamine 2000 kit, the levels of miR-221 in each group were detected by RT-PCR. Flow cytometry was used to detect the effects of miR-221 on cell cycle and apoptosis. Transwell assay was used to detect cell migration and invasion. Western blot was used to detect the effects of miR-221 on proliferating cell nuclear antigen (PCNA), Caspase 3, Cyclin D1 and MMP-9 proteins in BMNC. Luciferase reporter gene assay was used to detect the targeting relationship between miR-221 and Wnt gene. RESULT: The expression level of miR-221 in the miR-221 group was significantly higher than that in the control group and the miR-221-NC group (P<0.05). MTT assay showed that, after transfection for 2, 3, 4 and 5 days, the cell proliferation level in miR-221 group was significantly lower than that in the control group and the miR-221-NC group (P<0.05). The cell ratio of G0/G1 phase was (73.25±8.1)% in the miR-221 group, which was significantly higher than that in the control group and the miR-221-NC group (P<0.05); moreover, the cell ratio of S phase in the miR-221 group was (12.37±1.6)%,which was significantly lower than that in the control group and the miR-221-NC group (P<0.05). The percentage of apoptotic cells in the miR-221 group was (24.68±3.87)%, which was significantly higher than that in the control group and the miR-221-NC group (P<0.05). Transwell cell invasion experiment showed that the number of invasive cells in the miR-221 group was 23.42±3.62, which was significantly lower than that in the control group and the miR-221-NC group (P<0.05). Transwell cell migration assay showed that the number of migrating cells in the miR-221 group was 34.86±5.32, which was significantly lower than that in the control group and the miR-221-NC group (P<0.05). The relative level of PCNA, Cyclin D1 and MMP-9 in the miR-221 group was 0.26±0.03, 0.17±3.61 and 0.14±0.02, respectively, which was significantly lower than those in the control group and the miR-221-NC group (P<0.05), while the relative level of Caspase-3 in the miR-221 group was 0.37±0.05, which was significantly higher than that in the control group and the miR-221-NC group (P<0.05). Luciferase reporter assay showed that the activity of luciferase in Wnt wild type plasmid was significantly inhibited by miR-221 (P<0.05). CONCLUSION: miR-221 can inhibit the proliferation, migration and invasion of BMNC, moreover can promote cell apoptosis, which may be related with the inhibition of Wnt/ß- catenin signaling pathway.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1449-1454, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607297

RESUMO

OBJECTIVE: To analyze and investigate the expression levels of HES1, C-MYC and NF-kB in peripheral blood of patients with T cell acute lymphoblastic leukemia (T-ALL) and their significance. METHODS: Sixty patients with T-ALL and 60 patients with acute myelogenous leukemia (AML) diagnosed in our hospital from June 2012 to March 2015 were enrolled in T-ALL group and AML group, respectively. Another 30 healthy people were enrolled in the control group. Peripheral blood was collected to detect the expression levels of HES1, C-MYC and NF-kB by RT-PCR. The general data and the expression of HES1, C-MYC and NF-kB in peripheral blood were compared among the patients with different type of leukemia, cytogenetical types and different prognosis. RESULTS: There was no significant difference in baseline data, such as age and sex among the 3 groups (P>0.05). The Hb level, WBC and Plt count, BM blast cell ratio in T-ALL and AML groups all were significantly higher than those in control group (P<0.01), but there were no statistical difference in above-mentioned indicators between T-ALL and AML groups (P>0.05). The expression levels of HES1, C-MYC and NF-kB in peripheral blood among 3 groups were significantly differenct (P<0.01), the expressions levels of HES1, C-MYC and NF-kB in T-ALL and AML groups were significantly higher than those in control were significantly group (P<0.01), moreover, the expression levels of above-mentional indicators in T-ALL groups were significantly higher than than those in AML group (P<0.01). The expression levels of HES1, C-MYC and NF-kB iin T-ALL patients with poor prognosis were significantly higher than those in T-ALL patients with favorable prognosis (P<0.01); the expression levels of HES1, C-MYC and NF-kB in peripheral blood of patients with different theraptic efficacy were follow: complete remission group<partial remission group<no remission group (P<0.01). CONCLUSION: The HES1, C-MYC and NF-kB are highly expressed in peripheral blood of the patients with T-ALL, moreover, the expression levels maybe different, because of the cytogenetic, and theraptic efficacy.

4.
Sci Rep ; 9(1): 13824, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554845

RESUMO

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections and hospital visits during infancy and childhood. Although risk factors for RSV infection have been identified, the role of microbial species in the respiratory tract is only partially known. We aimed to understand the impact of interactions between the nasal microbiome and host transcriptome on the severity and clinical outcomes of RSV infection. We used 16 S rRNA sequencing to characterize the nasal microbiome of infants with RSV infection. We used RNA sequencing to interrogate the transcriptome of CD4+ T cells obtained from the same set of infants. After dimension reduction through principal component (PC) analysis, we performed an integrative analysis to identify significant co-variation between microbial clade and gene expression PCs. We then employed LIONESS (Linear Interpolation to Obtain Network Estimates for Single Samples) to estimate the clade-gene association patterns for each infant. Our network-based integrative analysis identified several clade-gene associations significantly related to the severity of RSV infection. The microbial taxa with the highest loadings in the implicated clade PCs included Moraxella, Corynebacterium, Streptococcus, Haemophilus influenzae, and Staphylococcus. Interestingly, many of the genes with the highest loadings in the implicated gene PCs are encoded in mitochondrial DNA, while others are involved in the host immune response. This study on microbiome-transcriptome interactions provides insights into how the host immune system mounts a response against RSV and specific infectious agents in nasal microbiota.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31370177

RESUMO

Land subsidence was once a major geo-hazard in the city of Shanghai, China. From 1921 to 1965, the maximum cumulative land subsidence in the urban areas of China reached 2.6 m. This large subsidence has resulted in high economic losses for Shanghai. The Regulation of Prevention and Control of Land Subsidence of Shanghai Municipality was published in 2013 (simply cited as the 2013-regulation in the following context). The characteristics of the 2013-regulation included the combination of the subsidence monitoring network and the groundwater detection network due to both the effects of groundwater withdrawal and construction. In addition, the setting up of a supervision system was also incorporated in the 2013-regulation. To control the land subsidence, Shanghai demarcated three land subsidence control zones, where special measures have been implemented. From a strategic environmental assessment (SEA) point of view, the 2013-regulation attains a high total score, indicating that the control of groundwater withdrawal and recharge is effective. The observed land subsidence over the past six years also confirms the effectiveness of the 2013-regulation with the most consideration of SEA for sustainable environment protection in Shanghai. However, more effort should be made in the implementation of SEA in land subsidence control in the future.

6.
Zhen Ci Yan Jiu ; 44(6): 405-11, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31368262

RESUMO

OBJECTIVE: To observe the influence of scalp acupuncture on cerebral infarct size and expression of IL-10, IL-6, and IL-1ß in the para-hippocampal gyrus in acute ischemic cerebrovascular disease(AICD) rats, so as to investigate its mechanisms underlying improvement of AICD. METHODS: Forty-eight male SD rats were randomly allocated to normal control (control), AICD model, medication, and scalp acupuncture groups (n=12 per group). The AICD model was established by occlusion of the middle cerebral artery (MCAO). Rats of the medication group received intraperitoneal injection of Ammonium 1-Pyrrolidinedithiocarbamate (APDC, 100 mg•kg-1•d-1), once daily for 7 days. Scalp acupuncture stimulation was applied to bilateral "Dingnieqianxiexian" (MS6) once daily for 7 days. Before and after intervention, the neurologic deficit score (NDS) and the neurological score (NS) were evaluated according to Longa's and Schäbitz's methods, respectively. At the end of the intervention, the para-hippocampal gyrus and whole brain were collected respectively. The expression levels of IL-10, IL-6 and IL-1ß in the para-hippocampal gyrus tissue were detected by immunohistochemistry, and the cerebral infarct volume of the brain was detected by triphenyltetrazollium chloride (TTC) staining after sectioning. RESULTS: Following modeling, the NDS, NS and the expression of IL-10, IL-6 and IL-1ß in para-hippocampal gyrus were significantly increased in the model group compared with the control group (P<0.01). After the intervention, the NDS, NS and infarct volume, and the expression levels of IL-6 and IL-1ß in the para-hippocampal gyrus were significantly decreased in both medication and scalp acupuncture groups compared with the model group (P<0.05), and the expression of IL-10 was further obviously up-regulated in the scalp acupuncture group (P<0.05) rather than in the medication group (P>0.05). The effect of scalp acupuncture was obviously superior to that of medication in up-regulating IL-10 expression level (P<0.05). No significant differences were found between the medication and scalp acupuncture groups in the levels of NDS, NS, infarct volume, IL-6 and IL-1ß proteins (P>0.05). CONCLUSION: Scalp acupuncture can improve neurological function and reduce infarct volume in AICD rats, which may be associated with its function in up-regulating the expression of IL-10 and in inhibiting the expression of IL-6 and IL-1ß to reduce inflammation reaction.


Assuntos
Terapia por Acupuntura , Isquemia Encefálica , Animais , Interleucina-10 , Interleucina-1beta , Interleucina-6 , Masculino , Giro Para-Hipocampal , Ratos , Ratos Sprague-Dawley , Couro Cabeludo
7.
J Agric Food Chem ; 67(37): 10458-10469, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31469568

RESUMO

Mud crab (Scylla paramamosain) is a commonly consumed seafood as a result of its high nutritional value; however, it is associated with food allergy. The current understanding of crab allergens remains insufficient. In the present study, an 18 kDa protein was purified from crab muscle and confirmed to be myosin light chain 1 (MLC1) by matrix-assisted laser desorption/ionization-tandem time-of-flight mass spectrometry. Total RNA was isolated and amplified to obtain a MLC1 open reading frame of 462 bp, encoding 154 amino acids. A structural analysis revealed that recombinant MLC1 (rMLC1) expressed in Escherichia coli contained α-helix and random coil. Moreover, rMLC1 displayed strong immunoactivity by dot blot and a basophil activation test. Furthermore, seven allergenic epitopes of MLC1 were predicted, and five critical epitope regions were identified by an inhibition enzyme-linked immunosorbent assay and human mast cell degranulation assay. This comprehensive research of an allergen helps to conduct component-resolved diagnoses and immunotherapies related to crab allergies.


Assuntos
Alérgenos/imunologia , Proteínas de Artrópodes/imunologia , Braquiúros/genética , Clonagem Molecular , Epitopos/imunologia , Cadeias Leves de Miosina/imunologia , Alérgenos/química , Alérgenos/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Braquiúros/química , Braquiúros/imunologia , Degranulação Celular , Epitopos/química , Epitopos/genética , Humanos , Mastócitos/imunologia , Cadeias Leves de Miosina/química , Cadeias Leves de Miosina/genética , Fases de Leitura Aberta , Alinhamento de Sequência
8.
Chem Asian J ; 14(17): 2966-2978, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31286657

RESUMO

A series of Fe-Ni mixed-oxide catalysts were synthesized by using the sol-gel method for the reduction of NO by CO. These Fe-Ni mixed-oxide catalysts exhibited tremendously enhanced catalytic performance compared to monometallic catalysts that were prepared by using the same method. The effects of Fe/Ni molar ratio and calcination temperature on the catalytic activity were examined and the physicochemical properties of the catalysts were characterized by using XRD, Raman spectroscopy, N2 -adsorption/-desorption isotherms, temperature-programmed reduction with hydrogen (H2 -TPR), temperature-programmed desorption of nitric oxide (NO-TPD), and X-ray photoelectron spectroscopy (XPS). The results indicated that the reduction behavior, surface oxygen species, and surface chemical valence states of iron and nickel in the catalysts were the key factors in the NO elimination. Fe0.5 Ni0.5 Ox that was calcined at 250 °C exhibited excellent catalytic activity of 100 % NO conversion at 130 °C and a lifetime of more than 40 hours. A plausible mechanism for the reduction of NO by CO over the Fe-Ni mixed-oxide catalysts is proposed, based on XPS and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analyses.

9.
Nat Commun ; 10(1): 3192, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324803

RESUMO

Hepatitis B virus (HBV) X protein, HBx, interacts with anti-apoptotic Bcl-2 and Bcl-xL proteins through its BH3-like motif to promote HBV replication and cytotoxicity. Here we report the crystal structure of HBx BH3-like motif in complex with Bcl-xL where the BH3-like motif adopts a short α-helix to snuggle into a hydrophobic pocket in Bcl-xL via its noncanonical Trp120 residue and conserved Leu123 residue. This binding pocket is ~2 Å away from the canonical BH3-only binding pocket in structures of Bcl-xL with proapoptotic BH3-only proteins. Mutations altering Trp120 and Leu123 in HBx impair its binding to Bcl-xL in vitro and HBV replication in vivo, confirming the importance of this motif to HBV. A HBx BH3-like peptide, HBx-aa113-135, restores HBV replication from a HBx-null HBV replicon, while a shorter peptide, HBx-aa118-127, inhibits HBV replication. These results provide crucial structural and functional insights into drug designs for inhibiting HBV replication and treating HBV patients.

10.
Bioresour Technol ; 289: 121674, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31247527

RESUMO

The objective of this study is to investigate the pyrolysis and kinetic characteristics of three varieties of the bamboo subfamily via thermogravimetry/Fourier transform infrared spectrometry (TG-FTIR) coupling technologies. The pyrolysis process can be divided into three stages of dehydration, volatilization, and carbonization. TG-FTIR analysis revealed that evolved gas is constituted by CO2, CO, CH4, H2O, NO, NO2, formic acid, HCN, and CO functional groups as major pyrolysis products. The kinetic parameters of pyrolysis were calculated using model-free methods of distributed activation energy (DAEM). With an increase in conversion, the activation energy of each bamboo subfamily exhibited distinct variations. The average values of activation energy for moso bamboo, bambusa multiplex, and black bamboo determined by DAEM were 201.59, 220.49, and 224.47 kJ/mol, respectively. Results of thermodynamic and kinetic analysis indicate that the bamboo subfamily shows great potential as an alternative fuel by pyrolysis.


Assuntos
Poaceae/química , Gases/química , Cinética , Pirólise , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Termogravimetria , Volatilização
11.
Curr Top Med Chem ; 19(15): 1289-1304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31210108

RESUMO

Microtubules are essential for the mitotic division of cells and have been an attractive target for antitumour drugs due to the increased incidence of cancer and significant mitosis rate of tumour cells. In the past few years, tubulin-colchicine binding site, as one of the three binding pockets including taxol-, vinblastine- and colchicine-binding sites, has been focused on to design tubulin-destabilizing agents including inhibitors, antibody-drug conjugates and degradation agents. The present review is the first to cover a systemic and recent synopsis of tubulin-colchicine binding site agents. We believe that it would provide an increase in our understanding of receptor-ligand interaction pattern and consciousness of a series of challenges about tubulin target druggability.


Assuntos
Antineoplásicos/farmacologia , Colchicina/farmacologia , Imunoconjugados/farmacologia , Neoplasias/tratamento farmacológico , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Sítios de Ligação/efeitos dos fármacos , Colchicina/química , Colchicina/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imunoconjugados/química , Imunoconjugados/metabolismo , Mitose/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/patologia , Tubulina (Proteína)/química , Moduladores de Tubulina/química , Moduladores de Tubulina/metabolismo
12.
J Mol Med (Berl) ; 97(8): 1213-1214, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203376

RESUMO

In Figure 7f the panel for c-myc of MDA-MB-468 was erroneously duplicated. The corrected version of the figure is shown in this paper. This correction does not influence the conclusion of the study and we sincerely apologize for this oversight.

15.
Zhen Ci Yan Jiu ; 44(3): 183-8, 2019 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-30945500

RESUMO

OBJECTIVE: To observe the effect of scalp-acupuncture intervention on the expression of Interleukin (IL)-10 mRNA, IL-6 mRNA and tumor necrosis factor (TNF) - α in the parahippocampal gyrus of cerebral ischemia (CI) rats, so as to explore its molecular mechanisms underlying improvement of CI. METHODS: A total of 64 male SD rats were randomized into normal control, model, medication and scalp-acupuncture groups (n=16 rats in each group). The focal CI model was established by middle cerebral artery occlusion. Intraperitoneal injection of Ammonium Pyrrolidine Dithiocarbamate (100 mg•kg-1•d-1) was administrated for rats in the medication group, once a day for 7 days. For rats of the scalp-acupuncture group, the acupuncture needles were rapidly inserted into bilateral Dingnieqianxiexian (MS6), followed by twirling the needles at 100 cycles/min for 1 min, once again every 10 min during 20 min' needle retention. The treatment was conducted once a day for 7 days. The neurologic deficit score (0-4 points, impaired consciousness, death, etc.) and neurological function score (motor, sensory and sensory tests, 0-10 points) were assessed according to Longa's (1989) and Schabitz's (2004) methods, respectively. The expression levels of IL-10 mRNA and IL-6 mRNA were detected by fluorescence quantitative PCR, and the expression of TNF-α was detected by immunohistochemistry. RESULTS: After modeling, the neurologic deficit and neurological function scores and the expression levels of IL-10 mRNA, IL-6 mRNA and TNF-α protein in the parahippocampus were significantly increased in the model group than in the normal control group (P<0.01). Following the intervention, the neurologic deficit and neurological function scores as well as IL-6 mRNA and TNF-α protein expression were significantly down-regulated in both scalp-acupuncture and medication groups (P<0.05), and the expression of IL-10 mRNA was obviously increased (P<0.05) relevant to the model group. CONCLUSION: Scalp-acupuncture can improve neurologic function in CI rats, which is related to its effects in up-regulating the expression of IL-10, then down-regulating the expression of IL-6 and TNF-α (reducing inflammatory response) in the parahippocampal gyrus.


Assuntos
Terapia por Acupuntura , Animais , Interleucina-10 , Interleucina-6 , Masculino , Giro Para-Hipocampal , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Couro Cabeludo , Fator de Necrose Tumoral alfa
18.
Int J Mol Sci ; 20(5)2019 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-30857324

RESUMO

This study aimed to characterize the full-length cDNA of MARK4 in Sus scrofa, and evaluated its potential role in the regulation of lipid accumulation in pig placental trophoblasts and analyzed signaling pathways involved, thereby providing insights into mechanisms for placental lipotoxicity induced by excessive back-fat during pregnancy of sows. The cDNA obtained with 5' and 3' RACE amplification covered 3216 bp with an open reading frame of 2259 bp encoding 752 amino acids. Multiple alignments and phylogenetic analysis revealed MARK4 protein of Sus scrofa had a high homology (95%⁻99%) to that of other higher vertebrates. After transfection, enhanced MARK4 significantly promoted lipogenesis in pig trophoblasts, as evidenced by accelerated lipid accumulation and consistently increased mRNA expressions of lipogenic genes DGAT1, LPIN1, LPIN3, LPL, PPARδ and SREBP-1c. Meanwhile, PPARγ remarkably inhibited the stimulating effect of MARK4 on non-receptor-mediated lipid accumulation in trophoblasts. Further analyses revealed WNT signaling enhanced lipid accumulation and activation of MARK4 in pig trophoblast cells. Finally, we demonstrated that WNT/ß-catenin signal pathway is involved in MARK4 activated lipogenesis. These results suggest that MARK4 promotes lipid accumulation in porcine placental trophoblasts and can be considered as a potential regulator of lipotoxicity associated with maternal obesity in the pig placenta.


Assuntos
Lipogênese , Proteínas Serina-Treonina Quinases/metabolismo , Sus scrofa/fisiologia , Trofoblastos/metabolismo , Animais , Células Cultivadas , Ativação Enzimática , Feminino , Modelos Moleculares , Filogenia , Placenta/citologia , Placenta/metabolismo , Gravidez , Conformação Proteica , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Sus scrofa/genética , Trofoblastos/citologia , Via de Sinalização Wnt
19.
Molecules ; 24(3)2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30709040

RESUMO

In order to obtain acetone sensor with excellent sensitivity, selectivity, and rapid response/recovery speed, graphene-like ZnO/graphene oxide (GO) nanosheets were synthesized using the wet-chemical method with an additional calcining treatment. The GO was utilized as both the template to form the two-dimensional (2-D) nanosheets and the sensitizer to enhance the sensing properties. Sensing performances of ZnO/GO nanocomposites were studied with acetone as a target gas. The response value could reach 94 to 100 ppm acetone vapor and the recovery time could reach 4 s. The excellent sensing properties were ascribed to the synergistic effects between ZnO nanosheets and GO, which included a unique 2-D structure, large specific surface area, suitable particle size, and abundant in-plane mesopores, which contributed to the advance of novel acetone vapor sensors and could provide some references to the synthesis of 2-D graphene-like metals oxide nanosheets.


Assuntos
Acetona/química , Grafite/química , Óxidos/química , Óxido de Zinco/química , Estrutura Molecular , Nanocompostos/química , Tamanho da Partícula , Porosidade , Análise Espectral
20.
Sci Rep ; 9(1): 1736, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30741948

RESUMO

Clostridium thermocellum is a good candidate organism for producing cellulosic biofuels due to its native ability to ferment cellulose, however its maximum biofuel titer is limited by tolerance. Wild type C. thermocellum is inhibited by 5 g/L n-butanol. Using growth adaptation in a chemostat, we increased n-butanol tolerance to 15 g/L. We discovered that several tolerant strains had acquired a D494G mutation in the adhE gene. Re-introducing this mutation recapitulated the n-butanol tolerance phenotype. In addition, it increased tolerance to several other primary alcohols including isobutanol and ethanol. To confirm that adhE is the cause of inhibition by primary alcohols, we showed that deleting adhE also increases tolerance to several primary alcohols.

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