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Wei Bin,Wang Ya-Kun,Yu Jin-Biao,Wang Si-Jia,Yu Yan-Lei,Xu Xue-Wei,Wang Hong 한국미생물학회 2021 The journal of microbiology Vol.59 No.10
C-Glycosides are an important type of natural product with significant bioactivities, and the C-glycosidic bonds of C-glycosides can be cleaved by several intestinal bacteria, as exemplified by the human faeces-derived puerarin-degrading bacterium Dorea strain PUE. However, glycoside hydrolases in these bacteria, which may be involved in the C-glycosidic bond cleavage of C-glycosides, remain largely unknown. In this study, the genomes of the closest phylogenetic neighbours of five puerarin-degrading intestinal bacteria (including Dorea strain PUE) were retrieved, and the protein-coding genes in the genomes were subjected to sequence similarity network (SSN) analysis. Only four clusters of genes were annotated as glycoside hydrolases and observed in the genome of D. longicatena DSM 13814T (the closest phylogenetic neighbour of Dorea strain PUE); therefore, genes from D. longicatena DSM 13814T belonging to these clusters were selected to overexpress recombinant proteins (CG1, CG2, CG3, and CG4) in Escherichia coli BL21(DE3). In vitro assays indicated that CG4 efficiently cleaved the O-glycosidic bond of daidzin and showed moderate β-D-glucosidase and β-D-xylosidase activity. CG2 showed weak activity in hydrolyzing daidzin and pNP- β-D-fucopyranoside, while CG3 was identified as a highly selective and efficient α-glycosidase. Interestingly, CG3 and CG4 could be selectively inhibited by daidzein, explaining their different performance in kinetic studies. Molecular docking studies predicted the molecular determinants of CG2, CG3, and CG4 in substrate selectivity and inhibition propensity. The present study identified three novel and distinctive glycoside hydrolases, highlighting the potential of SSN in the discovery of novel enzymes from genomic data.
Wei Hong,Wen-jie Li,Hui-chao Huang,Xiao-wei Weng,Yi-qin Zhang,Xiao-hui Liu,Yan-hua Guo,Ya-bin Su 한양대학교 청정에너지연구소 2022 Journal of Ceramic Processing Research Vol.23 No.6
In this experiment, we selected "Tangshan bone china" 10.5-inch white porcelain flat plate produced by five differententerprises as experimental samples to study the erosion of bone porcelain enamel by different kinds of acidic reagents atdifferent temperatures. The specific experimental process was as follows: at different temperatures, 20% hydrochloric acid,30% sulfuric acid, 100 g/L citric acid and 10% acetic acid were used to continuously erode the sample glaze for 10h, and thewhiteness and 45º mirror direction gloss were measured every 2h. The results show that different acidic reagents at differenttemperatures have significant differences in the erosion characteristics and strength of bone porcelain glaze, and the corrosionresistance of products from different enterprises also have significant differences.
Ya-Feng Song,Xiong-Xiong Kong,Wei-Bin Tang,Zhong-Qiang Suo,Huan Zhang,Chen-Yang Li,Qian Jia,Cai-Xia Xue,Yan-Wu Lu,Chao-Pu Yang 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.11
We investigate the polarization effect in intersubband transitions in polar and nonpolar GaN-based multiple-quantum well (MQW) structures for terahertz (THz) emissions by using systematic comparisons and design a nonpolar GaN/Al$_{0.2}$Ga$_{0.8}$N two-well-based MQW structure with an emitting photon of 7.27 THz (30.07 meV). Its lower energy separation (92.7 meV) matches the resonant phonon depopulation condition for better population inversion. It shows a lower threshold current density $J\rm_{th}$ at all temperatures (1.548 kA/cm$^2$ at 90 K) and a higher output power of up to 86.1 mW at 5.8 K and 33.6 mW at 100 K. Our results for the polar GaN MQW are very close to the experimental data in the literature. We find that the $J\rm_{th}$ of the nonpolar GaN MQW increases more slowly than that of the polar GaN MQW as temperature increases, indicating the nonpolar GaN MQW may be a worth-trying direction for improving the operation temperature. These results can provide meaningful references for the design and fabrication of nonpolar GaN-based THz MQW or quantum cascade structures.
Bin He,Ya-Li Mao,Ya Zhang,WEI YIN,CHANGJUN HOU,DANQUN HUO,Huanbao Fa 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.4
A highly sensitive and selective biomimetic sensor based on zinc porphyrin molecularly imprinted Polymer microspheres (MIPMs), gold nanoparticles (AuNPs) and carboxyl graphene (CG) nanomaterials was successfully developed for direct electrochemical detection of methyl parathion (MP). The novel strategy emphasized the fabrication of a porphyrin zinc-based sensor via attaching MIPMs on AuNPs/CG nanocomposites. MIPMs was prepared by free radical polymerization using MP as the template, Zinc porphyrin as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linking reagent and azobisisobutyronitrile (AIBN) as the initiator. The introduction of AuNPs/CG significantly increased the effective electrode area, and amplified the sensor signal. The modified electrode was characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The parameters of the detection process were also optimized. The biomimetic sensor exhibits a much wider linear dynamic range between 1.0 x 10 -6 mol L-1 and 8.0 x 10 -9 mol L-1 and the limit of detection (LOD) down to 3.16 x 10 -10 mol L-1 based on S/N = 3. The sensor had good reproducibility, stability and selectivity for MP detection. The developed sensor was successfully employed for the detection of MP in real samples.
Mesenchymal-to-epithelial transition of osteoblasts induced by Fam20c knockout
Geng Ya-Wei,Zhang Zhen,Jin Han,Da Jun-Long,Zhang Kai,Wang Jian-Qun,Guo Yu-Yao,Zhang Bin,Li Ying 한국유전학회 2022 Genes & Genomics Vol.44 No.2
Background: Fam20c is intimately related to tissue development and diseases. At present, it has been reported that Fam20c regulates the mineralization of osteoblasts, but there are few reports on other effects. Objective: To study the effect of Fam20c on osteoblasts by knocking out the Fam20c gene. Methods: Fam20c knockout osteoblasts were constructed by transfecting mouse osteoblasts with lentivirus. The proliferation, migration and mineralization of Fam20c knockout cells were detected by CCK-8, scratch test and alizarin red staining assays. The subcellular structure was observed by transmission electron microscopy. RT-PCR was used to detect the differential expression of mesenchymal-to-epithelial transition (MET)-related marker genes and core transcription factors. The differential expression of MET-related proteins was detected by immunofluorescence or Western blot. Transcriptome analysis of Fam20c knockout osteoblasts was performed, and real-time PCR was used to verify transcriptome analysis related to MET. Results: The proliferation ability of osteoblasts was not significantly changed after Fam20c deletion, but the migration ability and mineralization ability were significantly weakened. There were tight junctions between Fam20c knockout cells. The expression of mesenchymal cell marker genes and core transcription factors was significantly decreased, and the expression of epithelial cell marker genes was significantly increased. The expression of mesenchymal cell marker proteins was significantly decreased, and the expression of epithelial cell marker proteins was significantly increased. Multiple signalling molecules and pathways involved in MET have changed. Conclusions: Knockdown of Fam20c resulted in MET. Fam20c affects the transcription of key factors in osteoblast MET.
Yu Qing,Wu Li-bin,Zhang Fan,Wei Xiao-tong,Chen Pian-pian,Wang Shuai-ya,Cai Mei-yi,Shu Qi,Li Liao-yuan,Wu Zi-jian,Cai Rong-lin,Hu Ling 사단법인약침학회 2021 Journal of Acupuncture & Meridian Studies Vol.14 No.6
Background: Myocardial ischemia reperfusion injury (MIRI) is an important mechanism of post-myocardial infarction injury and a main cause of death in patients with ischemic heart disease. Electroacupuncture (EA) pretreatment is effective for the prevention and treatment of MIRI, but mechanisms mediating the effects of cardiovascular disease EA treatments remain unclear. Objectives: To determine whether the lateral hypothalamus (LHA) and the cerebellar fastigial nucleus (FN) are involved in the protective effects of EA stimulation on MIRI. Methods: EA pretreatment was performed for 7 days before the establishment of the MIRI model. ST-segment changes on electrocardiograms were recorded and the Curtis–Walker arrhythmia score was used to evaluate changes in reperfusion injury. Hematoxylin–eosin staining was applied to evaluate the pathological and morphological changes in myocardial tissue. c-fos expression in the LHA and FN was determined by immunofluorescence staining. Glutamic (Glu) and γ-Aminobutyric acid (GABA) levels were measured using a high-performance liquid chromatography-electrochemical method. Results: EA pretreatment reduced ST-segment elevation, arrhythmia scores, and morphological changes in MIRI myocardial cells in rats, and decreased the c-fos protein expression in LHA/FN nuclei. MIRI was associated with an imbalance between GABA and Glu levels, whereas EA pretreatment increased GABA levels and decreased Glu levels in the LHA/FN. Conclusion: FN and LHA are involved in the EA-mediated attenuation of MIRI. Pretreatment with EA plays a protective role in the myocardium by regulating Glu and GABA release in the LHA and FN.
Xiao-Bo Liu,Qiu-Ya Gu,Xiao-Bin Yu,Wei Luo 한국미생물학회 2012 The journal of microbiology Vol.50 No.6
As a promising alternative biofuel, biobutanol can be produced through acetone/butanol/ethanol (ABE) fermentation. Currently, ABE fermentation is still a small-scale industry due to its low production and high input cost. Moreover, butanol toxicity to the Clostridium fermentation host limits the accumulation of butanol in the fermentation broth. The wild-type Clostridium acetobutylicum D64 can only produce about 13 g butanol/L and tolerates less than 2% (v/v) butanol. To improve the tolerance of C. acetobutylicum D64 for enhancing the production of butanol, nitrogen ion beam implantation was employed and finally five mutants with enhanced butanol tolerance were obtained. Among these, the most butanol tolerant mutant C. acetobutylicum NT642 can tolerate above 3% (v/v) butanol while the wide-type strain can only withstand 2% (v/v). In batch fermentation, the production of butanol and ABE yield of C. acetobutylicum NT642 was 15.4 g/L and 22.3 g/L, respectively, which were both higher than those of its parental strain and the other mutants using corn or cassava as substrate. Enhancing butanol tolerance is a great precondition for obtaining a hyperyield producer. Nitrogen ion beam implantation could be a promising biotechnology to improve butanol tolerance and production of the host strain C. acetobutylicum.
Jiang-Ning Hu,Bin Shan,Ze-Yuan Deng,Jing Li,Ya-Wei Fan,Rong Liu,Zheng Ruan 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.6
A high-speed counter-current chromatography (HSCCC) method was developed for isolation of 5alkaloids from lotus (Nelumbo nucifera Gaertn.) leaves. The 2-phase solvent system of HSCCC composed of light petroleum-ethyl acetate-methanol-water was set up in 2-step separation process in the proportion of 3:5:3:5 for isolation of N-nornuciferine and armepavine, and in the proportion of 1:5:1:5 for that of anonaine, pronuciferine,and nuciferine. The purity of anonaine (14.6mg), pronuciferine (29.7 mg), N-nornuciferine (31.4 mg), nuciferine (22.1 mg),and armepavine (23.3 mg) isolated from 150 mg crude extract of lotus leaves were examined as 95.6, 88.2, 92.5,94.3, and 92.1%, respectively.