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121.
122.
Muhammad S. Nadeem Mohammed Razeeth Hani M. Z. Choudhry Firoz Anwar Mazin A. Zamzami Bibi N. Murtaza Fahad A. M. Al-Abbasi Mohammad I. Khan Abdul R. Shakoori 《Journal of cellular biochemistry》2020,121(1):125-134
Escherichia coli is frequently exploited for genetic manipulations and heterologous gene expression studies. We have evaluated the metabolic profile of E. coli strain BL21 (DE3) RIL CodonPlus after genetic modifications and subjecting to the production of recombinant protein. Three genetically variable E. coli cell types were studied, normal cells (susceptible to antibiotics) cultured in simple LB medium, cells harboring ampicillin-resistant plasmid pET21a (+), grown under antibiotic stress, and cells having recombinant plasmid pET21a (+) ligated with bacterial lactate dehydrogenase gene grown under ampicillin and standard isopropyl thiogalactoside (IPTG)-induced gene expression conditions. A total of 592 metabolites were identified through liquid chromatography-mass spectrometry/mass spectrometry analysis, feature and peak detection using XCMS and CAMERA followed by precursor identification by METLIN-based procedures. Overall, 107 metabolites were found differentially regulated among genetically modified cells. Quantitative analysis has shown a significant modulation in DHNA-CoA, p-aminobenzoic acid, and citrulline levels, indicating an alteration in vitamin K, folic acid biosynthesis, and urea cycle of E. coli cells during heterologous gene expression. Modulations in energy metabolites including NADH, AMP, ADP, ATP, carbohydrate, terpenoids, fatty acid metabolites, diadenosine tetraphosphate (Ap4A), and l -carnitine advocate major metabolic rearrangements. Our study provides a broader insight into the metabolic adaptations of bacterial cells during gene manipulation experiments that can be prolonged to improve the yield of heterologous gene products and concomitant production of valuable biomolecules. 相似文献
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Shan Pan Jun Leng Xinzhou Deng Honggang Ruan Lu Zhou Muhammad Jamal Ruijing Xiao Jie Xiong Qian Yin Yingjie Wu Meng Wang Wen Yuan Liang Shao Qiuping Zhang 《Journal of cellular biochemistry》2020,121(1):574-586
The NAD-dependent deacetylase Sirtuin 1 (SIRT1) plays a vital role in leukemogenesis. Nicotinamide (NAM) is the principal NAD+ precursor and a noncompetitive inhibitor of SIRT1. In our study, we showed that NAM enhanced the sensitivity of chronic myeloid leukemia (CML) to doxorubicin (DOX) via SIRT1. We found that SIRT1 high expression in CML patients was associated with disease progression and drug resistance. Exogenous NAM efficiently repressed the deacetylation activity of SIRT1 and induced the apoptosis of DOX-resistant K562 cells (K562R) in a dose-dependent manner. Notably, the combination of NAM and DOX significantly inhibited tumor cell proliferation and induced cell apoptosis. The knockdown of SIRT1 in K562R cells enhanced NAM+DOX-induced apoptosis. SIRT1 rescue in K562R reduced the NAM+DOX-induced apoptosis. Mechanistically, the combinatory treatment significantly increased the cleavage of caspase-3 and PARP in K562R in vitro and in vivo. These results suggest the potential role of NAM in increasing the sensitivity of CML to DOX via the inhibition of SIRT1. 相似文献
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Characterization of antifungal metabolites produced by Lactobacillus plantarum and Lactobacillus coryniformis isolated from rice rinsed water 总被引:1,自引:0,他引:1
Bukhari Shazia Anwer Salman Mahwish Numan Muhammad Javed Muhammad Rizwan Zubair Muhammad Mustafa Ghulam 《Molecular biology reports》2020,47(3):1871-1881
Molecular Biology Reports - A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore,... 相似文献
127.
Abid Suleman Kaliraj Lalitha Arif Muhammad Huzaifa Hurh Joon Ahn Jong Chan Yang Deok Chun Jung Seok-Kyu 《Molecular biology reports》2020,47(10):7699-7708
Molecular Biology Reports - Chrysanthemum indicum L. is a traditional oriental medicinal herb prepared as a tea from flowers that have been used in China and South Korea since ancient times. It has... 相似文献
128.
Saima Muzammil Mohsin Khurshid Iqra Nawaz Muhammad Hussnain Siddique Muhammad Zubair Muhammad Atif Nisar 《Biofouling》2020,36(4):492-504
AbstractAcinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production. 相似文献
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Daniel C. B. Jeffery Brandon A. Wyse Muhammad Attiq Rehman Geoffrey W. Brown Zhiying You Roxanne Oshidari Hisao Masai Krassimir Y. Yankulov 《Nucleic acids research》2013,41(18):8475-8488
Position-effect variegation (PEV) phenotypes are characterized by the robust multigenerational repression of a gene located at a certain locus (often called gene silencing) and occasional conversions to fully active state. Consequently, the active state then persists with occasional conversions to the repressed state. These effects are mediated by the establishment and maintenance of heterochromatin or euchromatin structures, respectively. In this study, we have addressed an important but often neglected aspect of PEV: the frequency of conversions at such loci. We have developed a model and have projected various PEV scenarios based on various rates of conversions. We have also enhanced two existing assays for gene silencing in Saccharomyces cerevisiae to measure the rate of switches from repressed to active state and vice versa. We tested the validity of our methodology in Δsir1 cells and in several mutants with defects in gene silencing. The assays have revealed that the histone chaperone Chromatin Assembly Factor I is involved in the control of epigenetic conversions. Together, our model and assays provide a comprehensive methodology for further investigation of epigenetic stability and position effects. 相似文献