共查询到8条相似文献,搜索用时 0 毫秒
1.
The article reviews applications of flow cytometry sorting in manufacturing of pharmaceuticals. Flow cytometry sorting is an extremely powerful tool for monitoring, screening and separating single cells based on any property that can be measured by flow cytometry. Different applications of flow cytometry sorting are classified into groups and discussed in separate sections as follows: (a) isolation of cell types, (b) high throughput screening, (c) cell surface display, (d) droplet fluorescent-activated cell sorting (FACS). Future opportunities are identified including: (a) sorting of particular fractions of the cell population based on a property of interest for generating inoculum that will result in improved outcomes of cell cultures and (b) the use of population balance models in combination with FACS to design and optimize cell cultures. 相似文献
2.
Advanced resources for plant genomics: a BAC library specific for the short arm of wheat chromosome 1B 总被引:1,自引:0,他引:1
Janda J Safár J Kubaláková M Bartos J Kovárová P Suchánková P Pateyron S Cíhalíková J Sourdille P Simková H Faivre-Rampant P Hribová E Bernard M Lukaszewski A Dolezel J Chalhoub B 《The Plant journal : for cell and molecular biology》2006,47(6):977-986
Common wheat (Triticum aestivum L., 2n = 6x = 42) is a polyploid species possessing one of the largest genomes among the cultivated crops (1C is approximately 17 000 Mb). The presence of three homoeologous genomes (A, B and D), and the prevalence of repetitive DNA make sequencing the wheat genome a daunting task. We have developed a novel 'chromosome arm-based' strategy for wheat genome sequencing to simplify this task; this relies on sub-genomic libraries of large DNA inserts. In this paper, we used a di-telosomic line of wheat to isolate six million copies of the short arm of chromosome 1B (1BS) by flow sorting. Chromosomal DNA was partially digested with HindIII and used to construct an arm-specific BAC library. The library consists of 65 280 clones with an average insert size of 82 kb. Almost half of the library (45%) has inserts larger than 100 kb, while 18% of the inserts range in size between 75 and 100 kb, and 37% are shorter than 75 kb. We estimated the chromosome arm coverage to be 14.5-fold, giving a 99.9% probability of identifying a clone corresponding to any sequence on the short arm of 1B. Each chromosome arm in wheat can be flow sorted from an appropriate cytogenetic stock, and we envisage that the availability of chromosome arm-specific BAC resources in wheat will greatly facilitate the development of ready-to-sequence physical maps and map-based gene cloning. 相似文献
3.
Foster G Hopkins GF Gunn GJ Ternent HE Thomson-Carter F Knight HI Graham DJ Edge V Synge BA 《Journal of applied microbiology》2003,95(1):155-159
AIMS: To compare the sensitivity of two pre-enrichment broth media prior to immunomagnetic separation for the isolation of Escherichia coli O157 from cattle faeces. METHODS AND RESULTS: One-gram portions of 721 cattle faeces collected from 43 farms were pre-enriched in buffered peptone water containing vancomycin, cefixime and cefsulodin (BPW-VCC) and buffered peptone water without additives (BPW-WOA), respectively. A total of 137 samples were positive for E. coli O157: 127 pre-enriched with BPW-WOA and 89 pre-enriched in BPW-VCC. Representative isolates were tested for phage type, verotoxin and eae (E. coli attaching and effacing) gene sequences, resulting in the recognition of eight different types. All the E. coli O157 types recognized were isolated by both methods except for three different strains, each of which were isolated only on a single occasion: two by BPW-WOA and another by BPW-VCC. CONCLUSIONS: The results clearly demonstrate, under the conditions of this study, that BPW without antibiotics was the superior pre-enrichment medium for the isolation of E. coli O157 from cattle faeces. SIGNIFICANCE AND IMPACT OF THE STUDY: The use of BPW-WOA in preference to BPW-VCC for the isolation of E. coli O157 from cattle faeces in future research and outbreak studies should lead to a higher number of positive isolates. 相似文献
4.
Böhm E Voglauer R Steinfellner W Kunert R Borth N Katinger H 《Biotechnology and bioengineering》2004,88(6):699-706
One of the major problems in the biotechnology industry is the selection of cell lines well suited for production of biopharmaceutical proteins. Usually, the most important selection criterion is the cell specific production rate. Nevertheless, a good producer cell line should have a number of additional advantageous properties, which allow the cell line to perform well in the type of bioreactor chosen for the process. However, the time and work required to select for high production rates as well as the lack of methods to specifically select for other cellular properties, usually prevents researchers from including such criteria into their screening program.With the Single Cell Secretion Assay it is possible to measure the specific production rates of individual cells by catching secreted product in an artificial matrix applied to the cell surface. Flow cytometric cell sorting then allows selection of rare cells with high production rates, which occur at frequencies as low as 10(-6). By combining this method with culture conditions that bring out a desired cellular property, we were able to isolate subclones with similar production rates, but improved performance from a recombinant Chinese hamster ovary cell line producing a human monoclonal antibody. The two desired cellular properties screened for were a non-growth associated production kinetic and improved stability in the absence of selective pressure. 相似文献
5.
Wansong Zong Rutao Liu Feng Sun Meijie Wang Pengjun Zhang Yihong Liu Yanmin Tian 《Protein science : a publication of the Protein Society》2010,19(2):263-268
Research on protein oxidative damage may give insight into the nature of protein functions and pathological conditions. In this work, the oxidative damage of bovine insulin on Au electrode was investigated by cyclic voltammetry (CV). The experimental results show that there are two anodic peaks for the oxidative damage of bovine insulin, which arise from the oxidation of the exposed disulfide bond S? SCYS7A,CYS7B, forming sulfenic acid RSOH (1.20 V, vs. SCE), sulfinic acid RSO2H and sulfonic acid RSO3H (1.35 V, vs. SCE). These in vitro findings not only demonstrate the applicability of CV in simulating/evaluating the oxidative damage of nonredox proteins but also find two promising candidates (two anodic peaks) for measuring insulin. 相似文献
6.
Hisateru Mitsuda Toshio Mitsunaga 《Bioscience, biotechnology, and biochemistry》2013,77(11):2265-2266
At least, four kinds of amylase inhibitors are found in culture of Streptomyces sp. No.280.1) A large amount of amylase inhibitors were produced by Streptomyces sp. No. 280 when cultivated on 3% oatmeal medium and it was found that the molecular weight of the inhibitors were transformed to smaller molecules during the cultivation time. The transformation of the amylase inhibitor was found to result from degradation of its carbohydrate moiety by α-amylase in the culture broth. The amylase inhibitor was hydrolyzed partially by the action of taka-amylase A or hog pancreatic α-amylase. With hydrolyzation of amylase inhibitor by α-amylase, neutral sugars (mainly maltose) were liberated from the amylase inhibitor and a modified inhibitor was newly formed, but amylase inhibitory activity against glucoamylase was not changed. The inhibitory activity against muscle Phosphorylase a, however, was almost completely lost. 相似文献
7.
Joseph R. England 《Journal of molecular biology》2010,398(4):518-529
The binding of RCC1 (regulator of chromosome condensation 1) to chromatin is critical for cellular processes such as mitosis, nucleocytoplasmic transport, and nuclear envelope formation because RCC1 recruits the small GTPase Ran (Ras-related nuclear protein) to chromatin and sets up a Ran-GTP gradient around the chromosomes. However, the molecular mechanism by which RCC1 binds to nucleosomes, the repeating unit of chromatin, is not known. We have used biochemical approaches to test structural models for how the RCC1 β-propeller protein could bind to the nucleosome. In contrast to the prevailing model, RCC1 does not appear to use the β-propeller face opposite to its Ran-binding face to interact with nucleosomes. Instead, we find that RCC1 uses a conformationally flexible loop region we have termed the switchback loop in addition to its N-terminal tail to bind to the nucleosome. The juxtaposition of the RCC1 switchback loop to its Ran binding surface suggests a novel mechanism for how nucleosome-bound RCC1 recruits Ran to chromatin. Furthermore, this model accounts for previously unexplained observations for how Ran can interact with the nucleosome both dependent and independent of RCC1 and how binding of the nucleosome can enhance RCC1's Ran nucleotide exchange activity. 相似文献
8.
In the early stages of infection, gaining control of the cellular protein synthesis machinery including its ribosomes is the ultimate combat objective for a virus. To successfully replicate, viruses unequivocally need to usurp and redeploy this machinery for translation of their own mRNA. In response, the host triggers global shutdown of translation while paradoxically allowing swift synthesis of antiviral proteins as a strategy to limit collateral damage. This fundamental conflict at the level of translational control defines the outcome of infection. As part of this special issue on molecular mechanisms of early virus–host cell interactions, we review the current state of knowledge regarding translational control during viral infection with specific emphasis on protein kinase RNA-activated and mammalian target of rapamycin-mediated mechanisms. We also describe recent technological advances that will allow unprecedented insight into how viruses and host cells battle for ribosomes. 相似文献