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191.
为了提高丙酮丁醇梭菌(Clostridium acetobutylicum)的丁醇耐受能力和培养基总糖产丁醇的转化率,通过原生质体融合的方法,研究了溶菌酶浓度及其作用时间、再生培养基种类、55℃条件下菌体致死时间、不同PEG分子量以及作用时间、Ca^2+和Mg^2+不同的添加量对丙酮丁醇梭菌原生质体制备、融合、再生的影响,得到了一套比较系统的丙酮丁醇梭菌的原生质体融合条件,同时通过气相色谱检测了融合菌的产溶剂能力并计算总糖转化率。结果显示,最终得到的215I菌株的总糖转化率比原始菌株提高了34.7%,产丁醇能力比原始菌株提高了32.2%,并且发现1株融合菌能产生新物质。原生质体融合方法在丙酸丁醇梭菌育种方面有广泛的应用潜力,通过融合得到的菌株为丁醇生产奠定了基础。 相似文献
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193.
Background: Triple-negative breast cancer (TNBC) is a refractory subtype of breast cancer, 25–30% of which have dysregulation in the PI3K/AKT pathway. The present study investigated the anticancer effect of erianin on TNBC cell line and its underlying mechanism.Methods: After treatment with erianin, MTT assay was employed to determine the MDA-MB-231 and EFM-192A cell proliferation, the nucleus morphological changes were observed by DAPI staining. The cell cycle and apoptotic proportion were detected by flow cytometry. Western blot was performed to determine the cell cycle and apoptosis-related protein expression and PI3K pathways. Finally, the antiproliferative activity of erianin was further confirmed by adding or not adding PI3K agonists SC79.Results: Erianin inhibited the proliferation of MDA-MB-231 and EFM-192A cells in a dose-dependent manner, the IC50 were 70.96 and 78.58 nM, respectively. Erianin could cause cell cycle arrest at the G2/M phase, and the expressions of p21 and p27 were up-regulated, while the expressions of CDK1 and Cyclin B1 were down-regulated. Erianin also induced apoptosis via the mitochondrial pathway, with the up-regulation of the expression of Cyto C, PARP, Bax, active form of Caspase-3, and Caspase-9. Furthermore, p-PI3K and p-Akt expression were down-regulated by erianin. After co-incubation with SC79, the cell inhibition rate of erianin was decreased, which further confirmed that the attenuated PI3K/Akt pathway was relevant to the pro-apoptotic effect of erianin.Conclusions: Erianin can inhibit the proliferation of TNBC cells and induce cell cycle arrest and apoptosis, which may ascribe to the abolish the activation of the PI3K/Akt pathway. 相似文献
194.
Chen Chong-Juan Liu Xue-Yan Wang Xian-Wei Hu Chao-Chen Xu Shi-Qi Mao Rong Bu Zhao-Jun Fang Yun-Ting Koba Keisuke 《Plant and Soil》2021,467(1-2):345-357
Plant and Soil - Plant carbon (C), nitrogen (N), phosphorus (P) levels and their stoichiometry and N uptake strategies are important aspects influencing vegetation composition and C dynamics in... 相似文献
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197.
Zhang Wenwen Xue Fang Xie Shangdan Chen Cheng Li Jingwei Zhu Xueqiong 《Molecular and cellular biochemistry》2021,476(1):45-55
Molecular and Cellular Biochemistry - This study investigated the effect of isoflurane on the proliferation of squamous cervical cancer cells, with focus on histone deacetylase 6 that is closely... 相似文献
198.
Fang Yu Jiangbo Wei Xiaolong Cui Chunjie Yu Wei Ni Jrg Bungert Lizi Wu Chuan He Zhijian Qian 《Nucleic acids research》2021,49(10):5779
Faithful genome integrity maintenance plays an essential role in cell survival. Here, we identify the RNA demethylase ALKBH5 as a key regulator that protects cells from DNA damage and apoptosis during reactive oxygen species (ROS)-induced stress. We find that ROS significantly induces global mRNA N6-methyladenosine (m6A) levels by modulating ALKBH5 post-translational modifications (PTMs), leading to the rapid and efficient induction of thousands of genes involved in a variety of biological processes including DNA damage repair. Mechanistically, ROS promotes ALKBH5 SUMOylation through activating ERK/JNK signaling, leading to inhibition of ALKBH5 m6A demethylase activity by blocking substrate accessibility. Moreover, ERK/JNK/ALKBH5-PTMs/m6A axis is activated by ROS in hematopoietic stem/progenitor cells (HSPCs) in vivo in mice, suggesting a physiological role of this molecular pathway in the maintenance of genome stability in HSPCs. Together, our study uncovers a molecular mechanism involving ALKBH5 PTMs and increased mRNA m6A levels that protect genomic integrity of cells in response to ROS. 相似文献
199.
Das Aparimita Ganesan Harsha Sriramulu Sushmitha Marotta Francesco Kanna N. R. Rajesh Banerjee Antara He Fang Duttaroy Asim K. Pathak Surajit 《Molecular and cellular biochemistry》2021,476(11):4117-4131
Molecular and Cellular Biochemistry - Oxidative stress has been known to be the underlying cause in many instances of cancer development. The new aspect of cancer genesis that has caught the... 相似文献
200.
Fang Yong E Cailing Wu Shixing Meng Zudong Qin Guifang Wang Rongying 《Cytotechnology》2021,73(6):775-785
Cytotechnology - Psoriasis is a skin disorder that is classed as an autoimmune disease. It is characterized by excessive proliferation, abnormal migration and differentiation of keratinocytes, as... 相似文献