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881.
Dominique T. Monteil Xiao Shen Giulia Tontodonati Lucia Baldi David L. Hacker Florian M. Wurm 《Analytical biochemistry》2016
Disposable orbitally shaken TubeSpin bioreactor 600 tubes (TS600s) were recently developed for the bench-scale cultivation of animal cells in suspension. Here we compared batch cultures of Sf9 insect cells in TS600s, spinner flasks, and shake flasks. Superior cell growth was observed in TS600s and shake flasks as compared with spinner flasks, and more favorable oxygen-enriched cell culture conditions were observed in TS600s as compared with either spinner or shake flasks. The results demonstrated the suitability of TS600s as a disposable vessel for the cultivation of Sf9 cells in suspension. 相似文献
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Inactivation of nitrate reductase alters metabolic branching of carbohydrate fermentation in the cyanobacterium Synechococcus sp. strain PCC 7002 下载免费PDF全文
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Genome‐scale RNA interference screen identifies antizyme 1 (OAZ1) as a target for improvement of recombinant protein production in mammalian cells 下载免费PDF全文
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Chaolei?Zhang Hongwei?Shen Xibin?Zhang Xue?Yu Han?Wang Shan?Xiao Jihui?Wang Zongbao?K.?ZhaoEmail author 《Biotechnology letters》2016,38(10):1733-1738
Objectives
To improve production of lipids and carotenoids by the oleaginous yeast Rhodosporidium toruloides by screening mutant strains.Results
Upon physical mutagenesis of the haploid strain R. toruloides np11 with an atmospheric and room temperature plasma method followed by chemical mutagenesis with nitrosoguanidine, a mutant strain, R. toruloides XR-2, formed dark-red colonies on a screening plate. When cultivated in nitrogen-limited media, XR-2 cells grew slower but accumulated 0.23 g lipids/g cell dry wt and 0.75 mg carotenoids/g CDW. To improve its production capacity, different amino acids and vitamins were supplemented. p-Aminobenzoic acid and tryptophan had beneficial effects on cell growth. When cultivated in nitrogen-limited media in the presence of selected vitamins, XR-2 accumulated 0.41 g lipids/g CDW and 0.69 mg carotenoids/g CDW.Conclusions
A mutant R. toruloides strain with improved production profiles for lipids and carotenoids was obtained, indicating its potential to use combined mutagenesis for a more productive phenotype.889.
Wei Li Yi Xue Jingjing Li Jing Yuan Xiaotang Wang Wei Fang Zemin Fang Yazhong Xiao 《Biotechnology letters》2016,38(2):345-349
Objectives
To express and characterize a putative α-glucosidase, Pagl, from Pseudoalteromonas sp. K8 obtained via genome mining approach.Results
Pagl was expressed and purified to homogeneity, with a molecular mass of 60 kDa. It was optimally active at pH 8.5 and 30 °C, and showed cold-adapted activity. Pagl exhibited specific activity towards substrates with α-1,4-linkage, with the highest specific activity of 19.4 U/mg for maltose, followed by pNPαG and maltodextrins, suggesting that Pagl belongs to the type II α-glucosidase. Interestingly, the activity of Pagl is significantly enhanced (2.7 times) in the presence of 200 mM glucose.Conclusion
The unique catalytic properties of Pagl make it an attractive candidate for several industrial applications.890.