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951.
Propranolol is a nonselective beta-blocker of the beta-adrenergic receptors, and the S-enantiomer is more active compared with the R-enantiomer. Clinically, it has been shown to be effective in hypermetabolic burn patients by decreasing cardiac work, protein catabolism, and lipolysis. While gene expression profiles have recently been reported in children receiving propranolol treatment, variations from one individual to another may have influenced the data analysis. Using iTRAQ-coupled 2D LC-MS/MS analysis, we report here the first study of protein profile in vascular smooth muscle cells incubated separately with the two enantiomers of propranolol. Four types of cellular proteins including metabolic enzymes, signaling molecules, cytoskeletal proteins, and those involved in DNA synthesis/protein translation displayed changes. The higher protein level of a number of enzymes involved in cellular anabolism and antioxidant activity in cells incubated with the S-enantiomer, as revealed by LC-MS/MS, was further supported by real-time PCR and Western blot analyses. Significantly, the increase in the anabolic activity associated with the higher level of metabolic enzymes was also supported by the higher intracellular concentration of the metabolic cofactor NAD+ which was a result of an increased oxidation of NADH. Our findings therefore provide molecular evidence on metabolic effect associated with propranolol treatment. The metabolic enzymes identified in our study may in turn be useful targets for future pharmaceutical interventions to reduce clinical side effects following propranolol treatment. 相似文献
952.
Qian Ma Li Xia Heyun Wu Mingyang Zhuo Mengya Yang Ying Zhang Miao Tan Kexin Zhao Quanwei Sun Qingyang Xu Ning Chen Xixian Xie 《Biotechnology and bioengineering》2022,119(1):89-101
Compatible solutes are key for the ability of halophilic bacteria to resist high osmotic stress. They have received wide attention from researchers for their excellent osmotic protection properties. Hydroxyectoine is a particularly important compatible solute, but its production by microbes faces several challenges, including low titer/yield, the presence of the byproduct ectoine, and the requirement of high salinity. Here, we aimed to metabolically engineer Escherichia coli to efficiently produce hydroxyectoine in the absence of osmotic stress without accumulating the byproduct ectoine. First, combinatorial optimization of the expression strength of key genes in the ectoine synthesis module and hydroxyectoine synthesis module was conducted. After optimization of the expression of these genes, 12.12 g/L hydroxyectoine and 0.24 g/L ectoine were obtained at 36 h in shake-flask fermentation with the addition of the co-substrate α-ketoglutarate. Further optimization of the addition of α-ketoglutarate achieved the sole production of hydroxyectoine (i.e., no ectoine accumulation), indicating that the supply of α-ketoglutarate is critically important for sole hydroxyectoine production. Finally, quorum sensing-based auto-regulation of intracellular α-ketoglutarate pool was implemented as an alternative to α-ketoglutarate addition by coupling the expression of sucA with the esaI/esaR circuit, which led to 14.93 g/L hydroxyectoine with a unit cell yield of 1.678 g/g and no ectoine accumulation in the absence of osmotic stress. This is the highest reported titer of sole hydroxyectoine production under salinity-free fermentation to date. 相似文献
953.
Dakheel Khulood Hamid Abdul Rahim Raha Al-Obaidi Jameel R. Neela Vasantha Kumari Hun Tan Geok Mat Isa Mohd Noor Razali Nurhanani Yusoff Khatijah 《Biotechnology letters》2022,44(3):513-522
Biotechnology Letters - The degradation activity of two bacteriophages UPMK_1 and UPMK_2 against methicillin-resistant Staphylococcus aureus phages were examined using gel... 相似文献
954.
Randrianarison Rose Marie Lutz Meredith Torti Valeria Tan Chia Bonadonna Giovanna Randrianambinina Blanchard Rasoloharijaona Solofonirina Rabarison Harison Miaretsoa Longondraza Rarojoson Nianja Jemisa De Gregorio Chiara Valente Daria Gamba Marco Ratsimbazafy Jonah Giacoma Cristina 《International journal of primatology》2022,43(4):584-610
International Journal of Primatology - Deforestation around the world is a major threat to primates. Understanding primate species’ habitat and dietary requirements is critical in creating... 相似文献
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Zhu Kai Guo Song Han Guoyi Qiang Xiancheng Ma Mengmeng Xu Qinglei Tang Wenjie Tan Jun 《Molecular biology reports》2022,49(5):3783-3792
Molecular Biology Reports - Oxidative stress in the intervertebral disc leads to nucleus pulposus (NP) degeneration by inducing cell apoptosis. However, the molecular mechanisms underlying this... 相似文献
957.
Cheng Zhuru Zhu Xiaonian Zeng Dan Feng Qiao Tian Baodong Zheng Haiqing Tan Shengkui Zhu Chunjiang 《Molecular biology reports》2022,49(7):6199-6205
Molecular Biology Reports - The hematological phenotype and genotype analysis of hemoglobin New York (Hb New York) combined with α or β thalassemia has been rarely reported, and whether... 相似文献
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