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Objective To explore the effects of prohibitin 2(PHB2) on sensitivity of non-small cell lung cancer cell line A549 to erlotinib (Erl) and its potential mechanisms. Methods RACK1-specific small interfering RNA was transfected in A549 cells for knocking-down of PHB2. The effects of PHB2 inhibition on cell proliferation and apoptosis induced by Erl were observed. The colocalization of microtuble-associated protein light chain 3 alpha (LC3) and mitochondria was visualized by MitoTracker staining and green fluorescent protein-microtuble-associated protein light chain 3 alpha (GFP-LC3) transfection. Cell proliferation was detected by 5-ethynyl-2′-deoxyuridine (EdU) staining. Cell colony formation was evaluated by colony forming assay. Apoptotic index of A549 cells was evaluated by TUNEL. Western blot was used to measure the expressions of PHB2 and LC3Ⅱ. Mitochondrial transmembrane potential, cytochrome c and respiratory chain complex Ⅰ/Ⅱ/Ⅴ activity were analyzed by the commercially available kits. Results Compared with the siPHB2 and siCtrl+Erl group, the EdU-positive A549 cells and the number of cell colonies decreased significantly (P＜0.05), while the TUNEL-positive A549 cells increased significantly(P＜0.05) in the siPHB2+Erl group. In addition, compared with the siPHB2 and siCtrl+Erl group, mitochondrial transmembrane potential and respiratory chain complex Ⅰ/Ⅱ/Ⅴ activity decreased significantly (all P＜0.05) and the levels of cytochrome c increased in mitochondrial fractions (P＜0.05) and decreased in cytosolic fractions(P＜0.05) in the siPHB2+Erl group. Conclusions PHB2 inhibition significantly improves sensitivity of A549 cells to Erl,which may be explained by inhibition of PHB2-mediated mitochondrial autophagy.

The purpose of this study was to investigate the mechanism of EMP1 action in high glucose (HG)‐induced H9c2 cardiac cell pyroptosis and oxidative injury. Rat cardiomyocytes H9c2 were exposed to 33 mM glucose for 24, 48, or 72 h to induce cytotoxicity. EMP1‐siRNA, NLRP3 agonist Nigericin, and pcNDA‐RAS were used to treat H9c2 cells under HG conditions. Cell Counting Kit (CCK)‐8 assay showed that cell proliferation was decreased following HG induction, which was rescued by EMP1 knockdown. Our results also suggested that EMP1 siRNA transfection significantly decreased the apoptosis and pyroptosis of HG‐induced cells, as indicated by the reduction of NLRP3 IL‐1β, ASC, GSDMD, cleaved‐caspase1 and cleaved‐caspase3 levels in HG‐induced H9c2 cells. In addition, EMP1 knockdown alleviated HG‐induced mitochondrial damage and oxidative stress in H9c2 cells. NLRP3 activation reversed the inhibitory effects of EMP1 knockdown on pyroptosis and oxidative stress in HG‐induced H9c2 cells. Mechanistically, we found that EMP1 knockdown suppressed the RAS/RAF/MAPK signaling pathway in HG‐induced H9c2 cells. RAS overexpression blocked the protective effect of EMP1 knockdown on HG‐induced H9c2 cell apoptosis, pyroptosis, and oxidative injury. Our findings suggest that EMP1 knockdown treatment might provide a novel therapy for diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Higher alcohols (phenylethyl alcohol and isoamyl alcohol), as the crucial aroma compounds, have been found to associate with the sensory properties of various alcoholic products. The Ehrlich and Harris pathways are the main pathways for yeast to produce phenylethyl alcohol and isoamyl alcohol during the brewing process of alcoholic products, whereas the specific changes of the Ehrlich and Harris pathways in Wickerhamomyces anomalus under ethanol stress are still unclear. In this study, W. anomalus NCU003 with a high capacity for aroma compound production was treated with ethanol stress at different concentrations (3%, v/v, 6%, v/v and 9%, v/v) to study the effects on the expression levels of genes and metabolite content in the Ehrlich and Harris pathways. The results found that ethanol stress inhibited the production of phenylethyl alcohol and isoamyl alcohol, and the content decreased with the increase of ethanol concentrations. In the meantime, the up‐regulation of ARO1, CS, ARO8, Leu1, BAT2 and ilvs family genes in the Ehrlich and Harris pathways could lead to an increase in the synthesis of important precursor substances during the synthesis of phenylethyl alcohol and isoamyl alcohol. However, the significant down‐regulation of ARO10, PDC, ADH1 and AHD2 genes was the main reason for the low production of phenylethyl alcohol and isoamyl alcohol. These results could provide a theoretical reference for the construction of genetic engineering strains of W. anomalus in the future so as to reasonably control the content of higher alcohols during the brewing process of alcoholic products. [ABSTRACT FROM AUTHOR]

Saccharomyces cerevisiae plays a decisive role in the brewing of alcohol products, and the ideal growth and fermentation characteristics can give the pure flavor of alcohol products. However, S. cerevisiae can be affected profoundly by environmental factors during the brewing process, which have negative effects on the growth and fermentation characteristics of S. cerevisiae, and seriously hindered the development of brewing industry. Therefore, we summarized the environmental stress factors (ethanol, organic acids, temperature and osmotic pressure) that affect S. cerevisiae during the brewing process. Their impact mechanisms and the metabolic adaption of S. cerevisiae in response to these stress factors. Of note, S. cerevisiae can increase the ability to resist stress factors by changing the cell membrane components, expressing transcriptional regulatory factors, activating the anti-stress metabolic pathway and enhancing ROS scavenging ability. Meantime, the strategies and methods to improve the stress- tolerant ability of S. cerevisiae during the brewing process were also introduced. Compared with the addition of exogenous anti-stress substances, mutation breeding and protoplast fusion, it appears that adaptive evolution and genetic engineering are able to generate ideal environmental stress tolerance strains of S. cerevisiae and are more in line with the needs of the current brewing industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bio‐augmented Daqu is used to improve the microbial community and physicochemical parameters of fermented grains, thus affecting the flavor and quality of baijiu. This study investigated the effects of bio‐augmented Daqu inoculated with Aspergillus niger NCUF413.1 and Saccharomyces cerevisiae NCUF304.1 on the microbial community, aroma compounds, and physicochemical parameters of fermented grains during special‐flavor baijiu brewing. RESULTS: Compared with the control group (CG), the utilization of starch and production of ethanol in the inoculated group (IG) increased by 3.55% and 12.59%, respectively. The use of bio‐augmented Daqu changed the bacterial communities. For example, Kroppenstedsia was the dominant bacterial genus (the relative abundance was about 22%) in the CG while Lactobacillus was the main dominant genus (the relative abundance was more than 30%) in the IG on days 20–30. Lactobacillus showed a significant positive correlation with the aroma compounds. The use of bio‐augmented Daqu increased the aroma compound content – such as the ethyl heptanoate and ethyl hexanoate content. CONCLUSION: The addition of bio‐augmented Daqu with A. niger and S. cerevisiae could change microbial communities, resulting in an increase in the yield of ethanol and the aroma compound content of fermented grains, thus improving the quality of baijiu. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Tannase is an enzyme produced by microbial fermentation and is widely used in the food industry; however, the molecular mechanism of tannase production by Aspergillus has not yet been studied. This study was conducted to reveal the differences in Aspergillus carbonarius tannase enzymatic characterization, secondary structures and molecular mechanisms after treatment of the strain with atmospheric and room temperature plasma (ARTP). RESULTS: The results showed that the specific activity of tannase was improved by ARTP treatment, and it showed higher thermostability and tolerance to metal ions and additives. The enzymatic characterization and molecular docking results indicated that tannase had a higher affinity and catalytic rate with tannic acid as a substrate after ARTP treatment. In addition, the docking results indicated that Aspergillus tannases may catalyze tannic acid by forming two hydrogen‐bonding networks with neighboring residues. RNA‐seq analysis indicated that changes in steroid biosynthesis, glutathione metabolism, glycerolipid metabolism, oxidative phosphorylation pathway and mitogen‐activated protein kinase signaling pathways might be crucial reasons for the high production of tannase. CONCLUSION: ARTP enhanced the yield and properties of A. carbonarius tannase by changing the enzyme structure and cell metabolism. This study provides a theoretical basis for elucidating the molecular mechanism underlying high production of Aspergillus tannases. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]