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421.
B-Cell activating factor (BAFF) is critical for B cell survival and maturation; excessive expression of it corrupts B-cell
tolerance and may lead to autoimmunity. The gene, scFv-Fc, coding for the antibody of BAFF was inserted into the eukaryotic
expression vector, pPICZαA, and transformed into Pichia pastoris. A high-level expression strain was obtained using a ‘yeastern blotting’ method. The scFv-Fc antibody was purified and 56 mg
was obtained from 1 l of culture supernatant. It retained high binding activity to both soluble BAFF and membrane-bound BAFF. 相似文献
422.
The neural cell adhesion molecule (NCAM) plays a pivotal role in the development and maintenance of the nervous system via homophilic (NCAM–NCAM) and heterophilic (NCAM-other molecules) interactions. Many synthetic peptides have been engineered to mimic these interactions and induce NCAM-downstream signaling pathways. Such NCAM mimetics have displayed neuritogenic and neuroprotective properties, as well as synaptic modulation in vitro and in vivo. Furthermore, they have been used successfully in preclinical studies to treat neurological disorders including stroke, traumatic brain injury and Alzheimer’s disease. This review focuses on recent progress in the development of NCAM mimetic peptides, in particular, on establishing C3, plannexin, and FGL as therapeutic candidates for neurological disorders. 相似文献
423.
Identification of suitable endogenous control genes for microRNA gene expression analysis in human breast cancer 总被引:2,自引:0,他引:2
Pamela A Davoren Roisin E McNeill Aoife J Lowery Michael J Kerin Nicola Miller 《BMC molecular biology》2008,9(1):76
The discovery of microRNAs (miRNAs) added an extra level of intricacy to the already complex system regulating gene expression.
These single-stranded RNA molecules, 18–25 nucleotides in length, negatively regulate gene expression through translational
inhibition or mRNA cleavage. The discovery that aberrant expression of specific miRNAs contributes to human disease has fueled
much interest in profiling the expression of these molecules. Real-time quantitative PCR (RQ-PCR) is a sensitive and reproducible
gene expression quantitation technique which is now being used to profile miRNA expression in cells and tissues. To correct
for systematic variables such as amount of starting template, RNA quality and enzymatic efficiencies, RQ-PCR data is commonly
normalised to an endogenous control (EC) gene, which ideally, is stably-expressed across the test sample set. A universal
endogenous control suitable for every tissue type, treatment and disease stage has not been identified and is unlikely to
exist, so, to avoid introducing further error in the quantification of expression data it is necessary that candidate ECs
be validated in the samples of interest. While ECs have been validated for quantification of mRNA expression in various experimental
settings, to date there is no report of the validation of miRNA ECs for expression profiling in breast tissue. In this study,
the expression of five miRNA genes (let-7a, miR-10b, miR-16, miR-21 and miR-26b) and three small nucleolar RNA genes (RNU19, RNU48 and Z30) was examined across malignant, benign and normal breast tissues to determine the most appropriate normalisation strategy.
This is the first study to identify reliable ECs for analysis of miRNA by RQ-PCR in human breast tissue. 相似文献
424.
Arthur R. Gorter de Vries Philip A. de Groot Marcel van den Broek Jean-Marc G. Daran 《Microbial cell factories》2017,16(1):222
Background
The ease of use of CRISPR-Cas9 reprogramming, its high efficacy, and its multiplexing capabilities have brought this technology at the forefront of genome editing techniques. Saccharomyces pastorianus is an aneuploid interspecific hybrid of Saccharomyces cerevisiae and Saccharomyces eubayanus that has been domesticated for centuries and is used for the industrial fermentation of lager beer. For yet uncharacterised reasons, this hybrid yeast is far more resilient to genetic alteration than its ancestor S. cerevisiae.Results
This study reports a new CRISPR-Cas9 method for accurate gene deletion in S. pastorianus. This method combined the Streptococcus pyogenes cas9 gene expressed from either a chromosomal locus or from a mobile genetic element in combination with a plasmid-borne gRNA expression cassette. While the well-established gRNA expression system using the RNA polymerase III dependent SNR52 promoter failed, expression of a gRNA flanked with Hammerhead and Hepatitis Delta Virus ribozymes using the RNA polymerase II dependent TDH3 promoter successfully led to accurate deletion of all four alleles of the SeILV6 gene in strain CBS1483. Furthermore the expression of two ribozyme-flanked gRNAs separated by a 10-bp linker in a polycistronic array successfully led to the simultaneous deletion of SeATF1 and SeATF2, genes located on two separate chromosomes. The expression of this array resulted in the precise deletion of all five and four alleles mediated by homologous recombination in the strains CBS1483 and Weihenstephan 34/70 respectively, demonstrating the multiplexing abilities of this gRNA expression design.Conclusions
These results firmly established that CRISPR-Cas9 significantly facilitates and accelerates genome editing in S. pastorianus.425.
Linda H Münger Mar Garcia-Aloy Rosa Vázquez-Fresno Doreen Gille Albert Remus R Rosana Anna Passerini María-Trinidad Soria-Florido Grégory Pimentel Tanvir Sajed David S Wishart Cristina Andres Lacueva Guy Vergères Giulia Praticò 《Genes & nutrition》2018,13(1):26
Dairy and egg products constitute an important part of Western diets as they represent an excellent source of high-quality proteins, vitamins, minerals and fats. Dairy and egg products are highly diverse and their associations with a range of nutritional and health outcomes are therefore heterogeneous. Such associations are also often weak or debated due to the difficulty in establishing correct assessments of dietary intake. Therefore, in order to better characterize associations between the consumption of these foods and health outcomes, it is important to identify reliable biomarkers of their intake. Biomarkers of food intake (BFIs) provide an accurate measure of intake, which is independent of the memory and sincerity of the subjects as well as of their knowledge about the consumed foods. We have, therefore, conducted a systematic search of the scientific literature to evaluate the current status of potential BFIs for dairy products and BFIs for egg products commonly consumed in Europe. Strikingly, only a limited number of compounds have been reported as markers for the intake of these products and none of them have been sufficiently validated. A series of challenges hinders the identification and validation of BFI for dairy and egg products, in particular, the heterogeneous composition of these foods and the lack of specificity of the markers identified so far. Further studies are, therefore, necessary to validate these compounds and to discover new candidate BFIs. Untargeted metabolomic strategies may allow the identification of novel biomarkers, which, when taken separately or in combination, could be used to assess the intake of dairy and egg products. 相似文献
426.
Kun‐Jun Han William D. Pitman Misook Kim Donal F. Day Montgomery W. Alison Michael E. McCormick Giovanna Aita 《Global Change Biology Bioenergy》2013,5(4):358-366
Sweet sorghum (Sorghum bicolor (L.) Moench) is widely recognized as a highly promising biomass energy crop with particular potential to complement sugarcane production in diversified cropping systems. Agronomic assessments have led to identification of four cultivars well suited for such sugarcane‐based production systems in southern Louisiana. Sweet sorghum biofuel production systems are currently being developed, and research producing large sample numbers requiring ethanol yield assessment is anticipated. Fiber analysis approaches developed for forage evaluation appear to be useful for screening such large numbers of samples for relative ethanol yield. Chemical composition, forage fiber characteristics, digestibility, and ethanol production of sweet sorghum bagasse from the four cultivars were assessed. Measures of detergent fiber, lignin, and digestibility were highly correlated with ethanol production (P < 0.01). The best linear regression models accounted for about 80% of the variation among cultivars in ethanol production. Bagasse from the cultivar Dale produced more ethanol per gram of material than any of the other cultivars. This superior ethanol production was apparently associated with less lignin in stems of Dale. Forage evaluation measures including detergent fiber analyses, in vitro digestibility, and an in vitro gas production technique successfully identified the cultivar superior in ethanol yield indicating their usefulness for screening sweet sorghum samples for potential ethanol production in research programs generating large sample numbers from evaluations of germ plasm or agronomic treatments. These screening procedures reduce time and expense of alternatives such as hexose sugar assessment for calculating theoretical ethanol yield. 相似文献
427.
The reserves of fossil-based fuels, which currently seem sufficient to meet the global demands, is inevitably on the verge of exhaustion. Contemporary raw material for alternate fuel like biodiesel is usually edible plant commodity oils, whose increasing public consumption rate raises the need of finding a non-edible and fungible alternate oil source. In this quest, single cell oils (SCO) from oleaginous yeasts and fungi can provide a sustainable alternate of not only functional but also valuable (polyunsaturated fatty acids (PUFA)-rich) lipids. Researches are been increasingly driven towards increasing the SCO yield in order to realize its commercial importance. However, bulk requirement of expensive synthetic carbon substrate, which inflates the overall SCO production cost, is the major limitation towards complete acceptance of this technology. Even though substrate cost minimization could make the SCO production profitable is uncertain, it is still essential to identify suitable cheap and abundant substrates in an attempt to potentially reduce the overall process economy. One of the most sought-after in-expensive carbon reservoirs, agro-industrial wastes, can be an attractive replacement to expensive synthetic carbon substrates in this regard. The present review assess these possibilities referring to the current experimental investigations on oleaginous yeasts, and fungi reported for conversion of agro-industrial feedstocks into triacylglycerols (TAGs) and PUFA-rich lipids. Multiple associated factors regulating lipid accumulation utilizing such substrates and impeding challenges has been analyzed. The review infers that production of bulk oil in combination to high-value fatty acids, co-production strategies for SCO and different microbial metabolites, and reutilization and value addition to spent wastes could possibly leverage the high operating costs and help in commencing a successful biorefinery. Rigorous research is nevertheless required whether it is PUFA-rich oil production (for competing with algal omega oils) or neutral bulk oil production (for overcoming yield limitations and managing process economy) to establish this potential source as future resource. 相似文献
428.
Phytoplankton morphological response to the underwater light conditions in a vegetated wetland 总被引:2,自引:3,他引:2
This study analyses the influence of the underwater light climate on the morphometric characteristics of the phytoplankton
at the population and community levels. The differences in light conditions across the floodplain were mainly defined by the
patchiness of floating macrophytes and humic acids concentration. A morphometric response at the community level to the underwater
PAR was registered. Sites with strong light constraints were characterised by non-flagellated organisms or with a small proportion
of unicellular flagellates. Short organisms (<10 μm) with a unit volume of less than 1,000 μm3 and a high surface:volume ratio (S/V >2) were the morphotypes related to poorly illuminated environments. Moreover, the organisms
showed forms more slender under these limiting conditions. This pattern was different to that registered in well-illuminated
sites where longer and larger organisms, with a smaller S/V and frequently flagellated, coexisted with the previously mentioned
organisms. The autotrophic picoplankton, the smallest phytoplankton fraction, revealed lower abundances at sites with higher
humic substances. Short term morphological changes were additionally studied for the dominant species by means of mesocosm
experiments simulating different light climates. Intraspecific morphological plasticity was observed with respect to the filament
length and the vacuolization of cells.
Electronic Supplementary Material Supplementary material is available for this article at and is available to authorized users. 相似文献
429.
Gluconic acid (GA) is a multifunctional carbonic acid regarded as a bulk chemical in the food, feed, beverage, textile, pharmaceutical,
and construction industries. The favored production process is submerged fermentation by Aspergillus niger utilizing glucose as a major carbohydrate source, which accompanied product yield of 98%. However, use of GA and its derivatives
is currently restricted because of high prices: about US$ 1.20–8.50/kg. Advancements in biotechnology such as screening of
microorganisms, immobilization techniques, and modifications in fermentation process for continuous fermentation, including
genetic engineering programmes, could lead to cost-effective production of GA. Among alternative carbohydrate sources, sugarcane
molasses, grape must show highest GA yield of 95.8%, and banana must may assist reducing the overall cost of GA production.
These methodologies would open new markets and increase applications of GA.
Authors’ contributions OVS and RK are the sole contributors of this original review article. This review is based upon the published research in
the area of gluconic acid fermentation. 相似文献
430.
Han Hu Kshitij Khatri Joshua Klein Nancy Leymarie Joseph Zaia 《Glycoconjugate journal》2016,33(3):285-296
Despite the publication of several software tools for analysis of glycopeptide tandem mass spectra, there remains a lack of consensus regarding the most effective and appropriate methods. In part, this reflects problems with applying standard methods for proteomics database searching and false discovery rate calculation. While the analysis of small post-translational modifications (PTMs) may be regarded as an extension of proteomics database searching, glycosylation requires specialized approaches. This is because glycans are large and heterogeneous by nature, causing glycopeptides to exist as multiple glycosylated variants. Thus, the mass of the peptide cannot be calculated directly from that of the intact glycopeptide. In addition, the chemical nature of the glycan strongly influences product ion patterns observed for glycopeptides. As a result, glycopeptidomics requires specialized bioinformatics methods. We summarize the recent progress towards a consensus for effective glycopeptide tandem mass spectrometric analysis. 相似文献