Gene Cloning, Expression, and Characterization of a Novel β-Mannanase from Bacillus circulans CGMCC 1416

( Yan An Li ),( Pei Long Yang ),( Kun Meng ),( Ya Ru Wang ),( Hui Ying Luo ),( Ning Feng Wu ),( Yun Liu Fan ),( Bin Yao ) 한국미생물 · 생명공학회 2008 Journal of microbiology and biotechnology Vol.18 No.1

A DNA fragment containing 2,079 base pairs from Bacillus circulans CGMCC 1416 was cloned using degenerate PCR and inverse PCR. An open reading frame containing 981 bp was identified that encoding 326 amino acids residues, including a putative signal peptide of 31 residues. The deduced amino acid sequence showed the highest identity (68.1%) with endo-β-1,4-D-mannanase from Bacillus circulans strain K-1 of the glycoside hydrolase family 5 (GH5). The sequence encoding the mature protein was cloned into the pET-22b(+) vector and expressed in Escherichia coli as a recombinant fusion protein containing an N-terminal hexahistidine sequence. The fusion protein was purified by Ni2+ affinity chromatography and its hexahistidine tag cleaved to yield a 31-kDa β-mannanase having a specific activity of 481.55 U/mg. The optimal activity of the purified protein, MANB48, was at 58℃ and pH 7.6. The hydrolysis product on substrate locust bean gum included a monosaccharide and mainly oligosaccharides. The recombinant MANB48 may be of potential use in the feed industry.

Morphology-dependent Optical Properties of One-dimensional Nanostructure-arrayed Silicon

Shao-long Wu,Guo-an Cheng,Rui-ting Zheng,Xiao-ling Wu 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.6

The optical properties of one-dimensional nanostructure-arrayed silicon (1DNSASi), which wasfabricated by the metal assisted electroless chemical etching method under different conditions,were characterized in the wavelength range of 220 - 1000 nm. Whether the optical absorption ofthe 1DNSASi was enhanced relative to that of the polished Si was determined from the detailedmorphology of the 1D nanostructures. For the yellow 1DNSASi prepared at a high etchant concentrationand high temperatures, its optical absorption was relatively nice in the ultraviolet lightregion, while a gradual attenuation was shown in the visible and the near-infrared regions, and theoptical absorption was lower than that of the polished Si at wavelengths above 800 nm. When theeffects of zeroth-order reflectance and zero transmission were combined, the optical absorption ofthe black 1DNSASi prepared at a low etchant concentration and room temperature was very high(> 99%) in the wavelength range of 220 - 1030 nm and displayed a slight decrease at wavelengthsabove 1030 nm. Our results demonstrate that the optical absorption of the black 1DNSASi couldbe further improved by increasing the etching depth and exhibited its measurable maximum valuewhen the etching depth was large enough. These results indicate that the 1DNSASi may be apromising candidate for high-efficiency photovoltaic devices, high-sensitivity sensors and detectors.

Removal of NO with the hexamminecobalt(II) solution catalyzed by the activated carbon treated with acetic acid

Xiang-li Long,Bei-bei Duan,Hai-xia Cao,Ming-lei Jia,Long-an Wu 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.62 No.-

The simultaneous scrubbing of NO and SO2 can be finished with the Co(NH3)62+ ammonia solution. Activated carbon aids the regeneration of Co(NH3)62+ to retain the ability of absorbing NO. Acetic acid is tried to improve the catalytic capability of activated carbon. The best treatment condition is the carbon samples impregnated in 2.0 mol l−1 HAc solution for 20 h followed by being calcined at 600 °C for 4 h. The HAc modification increases surface area and acidic groups on the carbon surface. The experiments prove that the modified carbon can obtain a higher NO removal efficiency than the original carbon.

Luciferase Assay to Screen Tumour-specific Promoters in Lung Cancer

Xu, Rong,Guo, Long-Jiang,Xin, Jun,Li, Wen-Mao,Gao, Yan,Zheng, You-Xian,Guo, You-Hong,Lin, Yang-Jun,Xie, Yong-Hua,Wu, Ya-Qing,Xu, Rui-An Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Objective: Specific promoters could improve efficiency and ensure the safety of gene therapy. The aim of our study was to screen examples for lung cancer. Methods: The firefly luciferase gene was used as a reporter, and promoters based on serum markers of lung cancer were cloned. The activity and specificity of seven promoters, comprising CEACAM5 (carcinoembryonic antigen, CEA), GRP (Gastrin-Releasing Peptide), KRT19 (cytokeratin 19, KRT), SFTPB (surfactant protein B, SP-B), SERPINB3 (Squamous Cell Carcinoma Antigen, SCCA), SELP (Selectin P, Granule Membrane Protein 140kDa, Antigen CD62, GMP) and DKK1 (Dickkopf-1) promoters were compared in lung cancer cells to obtain cancer-specific examples with strong activity. Results: The CEACAM5, DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB promoters were cloned. Furthermore, we successfully constructed recombinant vector pGL-CEACAM5 (DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB) contained the target gene. After cells were transfectedwith recombinant plasmids, we found that the order of promoter activity from high to low was SERPINB3, DKK1, SFTPB, KRT19, CEACAM5, SELP and GRP and the order for promoters regarding specificity and high potential were SERPINB3, DKK1, SELP, SFTPB, CEACAM5, KRT19 and GRP. Conclusion: The approach adopted is feasible to screen for new tumour specific promoters with biomarkers. In addition, the screened lung-specific promoters might have potential for use in lung cancer targeted gene therapy research.

Fabrication and Electron Field Emission of Silicon Nanowires Synthesized by Chemical Etching

Fei Zhao,Dan-dan Zhao,Shao-long Wu,Guo-an Cheng,Rui-ting Zheng 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Vertically aligned silicon nanowire arrays, which were synthesized by using a Ag catalyst deposited with magnetron sputtering and an electrochemical etching process were investigated. The thickness of the Ag catalyst affects the microstructure of aligned silicon nanowire array. Vertically aligned silicon nanowire arrays with more uniform morphology structures were synthesized with a catalyst thickness of 40 nm on a single crystal silicon wafer at room temperature. The electron field emission data showed a lower turn-on field for silicon nanowire arrays fabricated with the electrochemical etching process. The field enhancement factor of the silicon nanowire arrays is as high as 1637. These data indicate that electrochemical etching technology is a cheap and good method for fabricating vertically aligned silicon nanowire arrays for applications in field emission devices. Vertically aligned silicon nanowire arrays, which were synthesized by using a Ag catalyst deposited with magnetron sputtering and an electrochemical etching process were investigated. The thickness of the Ag catalyst affects the microstructure of aligned silicon nanowire array. Vertically aligned silicon nanowire arrays with more uniform morphology structures were synthesized with a catalyst thickness of 40 nm on a single crystal silicon wafer at room temperature. The electron field emission data showed a lower turn-on field for silicon nanowire arrays fabricated with the electrochemical etching process. The field enhancement factor of the silicon nanowire arrays is as high as 1637. These data indicate that electrochemical etching technology is a cheap and good method for fabricating vertically aligned silicon nanowire arrays for applications in field emission devices.

Aberrant microRNAs Expression in CD133+/CD326+ Human Lung Adenocarcinoma Initiating Cells from A549

Sheng Lin,Zheng-tang Chen,Jian-guo Sun,Jing-bo Wu,Hai-xia Long,Cong-hui Zhu,Tong Xiang,Hu Ma,Zhong-quan Zhao,Quan Yao,An-mei Zhang,Bo Zhu 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.3

Increasing evidence demonstrates that miRNAs are in-volved in the dysregulation of tumor initiating cells (TICs) in various tumors. Due to a lack of definitive markers, cell sorting is not an ideal separation method for lung adeno-carcinoma initiating cells. In this study, we combined pa-clitaxel with serum-free medium cultivation (inverse-induc-tion) to enrich TICs from A549 cells, marked by CD133/ CD326, defined features of stemness. We next investigated aberrant microRNAs in this subpopulation compared to normal cells with miRNA microarray and found that 50 miRNAs exhibited a greater than 2-fold change in expres-sion. As further validation, 10 miRNAs were chosen to perform quantitative RT-PCR on the A549 cell line and primary samples. The results suggest that aberrant ex-pression of miRNAs such as miR-29ab, miR-183, miR-17-5p and miR-127-3P may play an important role in regulat-ing the bio-behavior of TICs.