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Biodiesel production from rubber seed oil using poly (sodium acrylate) supporting NaOH as a water-resistant catalyst 总被引:1,自引:0,他引:1
Poly (sodium acrylate) supporting NaOH (NaOH/NaPAA) was prepared by in situ polymerization of aqueous solution of acrylic acid with an over-neutralization by adding excess of NaOH. NaOH/NaPAA presented a promising selectivity for water absorbency and good water retention with negligible swelling capacity in the organic solvents of methanol, glycerol, rubber seed oil methyl esters, and rubber seed oil. NaOH/NaPAA catalysts showed a basic strength of 15.0 < H_ < 18.4 and their basicity increased with the increase of the NaOH loading amount. NaOH/NaPAA catalysts exhibited almost the same catalytic activity in the transesterification of rubber seed oil with methanol under the optimized reaction conditions compared to conventional homogeneous NaOH catalyst. Furthermore, the functional absorbent/catalyst system presented a good water resistance in the transesterification which retained high catalytic activity when a water concentration in the reaction system was less than 2 wt.%. 相似文献
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Kais Z Barsky SH Mathsyaraja H Zha A Ransburgh DJ He G Pilarski RT Shapiro CL Huang K Parvin JD 《Molecular cancer research : MCR》2011,9(8):1091-1099
To find genes and proteins that collaborate with BRCA1 or BRCA2 in the pathogenesis of breast cancer, we used an informatics approach and found a candidate BRCA interactor, KIAA0101, to function like BRCA1 in exerting a powerful control over centrosome number. The effect of KIAA0101 on centrosomes is likely direct, as its depletion does not affect the cell cycle, KIAA0101 localizes to regions coincident with the centrosomes, and KIAA0101 binds to BRCA1. We analyzed whether KIAA0101 protein is overexpressed in breast cancer tumor samples in tissue microarrays, and we found that overexpression of KIAA0101 correlated with positive Ki67 staining, a biomarker associated with increased disease severity. Furthermore, overexpression of the KIAA0101 gene in breast tumors was found to be associated with significantly decreased survival time. This study identifies KIAA0101 as a protein important for breast tumorigenesis, and as this factor has been reported as a UV repair factor, it may link the UV damage response to centrosome control. 相似文献
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Ningyan Zhang Liming Liu Calin Dan Dumitru Nga Rewa Houston Cummings Michael Cukan Youwei Jiang Yuan Li Fang Li Teresa Mitchell Muralidhar R Mallem Yangsi Ou Rohan N Patel Kim Vo Hui Wang Irina Burnina Byung-Kwon Choi Hans Huber Terrance A Stadheim Dongxing Zha 《MABS-AUSTIN》2011,3(3):289-298
Mammalian cell culture systems are used predominantly for the production of therapeutic monoclonal antibody (mAb) products. A number of alternative platforms, such as Pichia engineered with a humanized N-linked glycosylation pathway, have recently been developed for the production of mAbs. The glycosylation profiles of mAbs produced in glycoengineered Pichia are similar to those of mAbs produced in mammalian systems. This report presents for the first time the comprehensive characterization of an anti-human epidermal growth factor receptor 2 (HER2) mAb produced in glycoengineered Pichia, and a study comparing the anti-HER2 from Pichia, which had an amino acid sequence identical to trastuzumab, with trastuzumab. The comparative study covered a full spectrum of preclinical evaluation, including bioanalytical characterization, in vitro biological functions, in vivo anti-tumor efficacy and pharmacokinetics in both mice and non-human primates. Cell signaling and proliferation assays showed that anti-HER2 from Pichia had antagonist activities comparable to trastuzumab. However, Pichia-produced material showed a 5-fold increase in binding affinity to FcγIIIA and significantly enhanced antibody dependent cell-mediated cytotoxicity (ADCC) activity, presumably due to the lack of fucose on N-glycans. In a breast cancer xenograft mouse model, anti-HER2 was comparable to trastuzumab in tumor growth inhibition. Furthermore, comparable pharmacokinetic profiles were observed for anti-HER2 and trastuzumab in both mice and cynomolgus monkeys. We conclude that glycoengineered Pichia provides an alternative production platform for therapeutic mAbs and may be of particular interest for production of antibodies for which ADCC is part of the clinical mechanism of action.Key words: glycoengineered Pichia, anti-HER2, trastuzumab, xenograft, PK, ADCC 相似文献
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将猪繁殖与呼吸综合征病毒 (PRRSV)BJ 4毒株N基因克隆至原核表达载体pET2 8a中 ,得到重组表达载体pET2 8 N ,转化EscherichiacoliBL2 1(DE3)细胞 ,获得可溶性表达 ,表达量占菌体蛋白的 2 8%。经ProbandNi2 亲和层析获得重组蛋白P2 8 N ,圆二色谱 (CD)测定结果表明 ,P2 8 N重组蛋白螺旋占 2 6 1% ,折叠占 2 3 7% ,转角 19 8% ,卷曲占 30 3%。并进一步绘制出PRRSVN蛋白的二级结构图 相似文献
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Identification and characterization of piggyBac-like elements in the genome of domesticated silkworm, Bombyx mori 总被引:4,自引:0,他引:4
Xu HF Xia QY Liu C Cheng TC Zhao P Duan J Zha XF Liu SP 《Molecular genetics and genomics : MGG》2006,276(1):31-40
piggyBac is a short inverted terminal repeat (ITR) transposable element originally discovered in Trichoplusia ni. It is currently the preferred vector of choice for enhancer trapping, gene discovery and identifying gene function in insects and mammals. Many piggyBac-like sequences have been found in the genomes of phylogenetically species from fungi to mammals. We have identified 98 piggyBac-like sequences (BmPBLE1-98) from the genome data of domesticated silkworm (Bombyx mori) and 17 fragments from expressed sequence tags (ESTs). Most of the BmPBLE1-98 probably exist as fossils. A total of 21 BmPBLEs are flanked by ITRs and TTAA host dinucleotides, of which 5 contain a single ORF, implying that they may still be active. Interestingly, 16 BmPBLEs have CAC/GTG not CCC/GGG as the characteristic residues of ITRs, which is a surprising phenomenon first observed in the piggyBac families. Phylogenetic analysis indicates that many BmPBLEs have a close relation to mammals, especially to Homo sapiens, only a few being grouped with the T. ni piggyBac element. In addition, horizontal transfer was probably involved in the evolution of the piggyBac-like elements between B. mori and Daphnia pulicaria. The analysis of the BmPBLEs will contribute to our understanding of the characteristic of the piggyBac family and application of piggyBac in a wide range of insect species. 相似文献
50.
Can Wang Zengxia Li Zhaohua Yang Hongbo Zhao Yong Yang Kangli Chen Xiumei Cai Liying Wang Yinghong Shi Shuangjian Qiu Jia Fan Xiliang Zha 《Journal of cellular biochemistry》2010,109(1):113-123
N‐acetylglucosaminyltransferase V (GnT‐V) has been reported to be positively associated with tumor progression, but its mechanism still remains unknown. In the present study, we found that GnT‐V overexpression not only changed the glycosylation of receptor protein tyrosine phosphatase kappa (RPTPκ) but also decreased its protein level. Moreover, GnT‐V overexpression decreased cell calcium‐independent adhesion and increased the tyrosine phosphorylation level of β‐catenin, in which RPTPκ played an important role. Since RPTPκ has an RXKR motif, which is a favored cleavage site for furin, we used furin inhibitor to further explore the effect of RPTPκ on the change of cell adhesion and β‐catenin signaling induced by GnT‐V. Our results showed that preventing RPTPκ cleavage rescued the above effects of GnT‐V, suggesting that furin cleavage could be one of the factors for RPTPκ to regulate cell adhesion and β‐catenin signaling in GnT‐V overexpression cell lines. In addition, the increased tyrosine phosphorylation level of β‐catenin was associated with the increased nuclear level of β‐catenin and downstream signaling molecules such as c‐myc and cyclin D1 that were associated with cell proliferation. Our results suggest that GnT‐V could decrease human hepatoma SMMC‐7721 cell adhesion and promote cell proliferation partially through RPTPκ. J. Cell. Biochem. 109: 113–123, 2010. © 2009 Wiley‐Liss, Inc. 相似文献