排序方式: 共有199条查询结果,搜索用时 437 毫秒
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Sujit Sadashiv Jagtap Saurabh Sudha Dhiman Tae-Su Kim In-Won Kim Jung-Kul Lee 《Applied microbiology and biotechnology》2014,98(2):661-669
A novel endo-β-1,4-glucanase (EG)-producing strain was isolated and identified as Armillaria gemina KJS114 based on its morphology and internal transcribed spacer rDNA gene sequence. A. gemina EG (AgEG) was purified using a single-step purification by gel filtration. The relative molecular mass of AgEG by sodium dodecyl sulfate polyacrylamide gel electrophoresis was 65 kDa and by size exclusion chromatography was 66 kDa, indicating that the enzyme is a monomer in solution. The pH and temperature optima for hydrolysis were 5.0 and 60 °C, respectively. Purified AgEG had the highest catalytic efficiency with carboxymethylcellulose (k cat/K m?=?3,590 mg mL?1 s?1) unlike that reported for any fungal EG, highlighting the significance of the current study. The amino acid sequence of AgEG showed homology with hydrolases from the glycoside hydrolase family 61. The addition of AgEG to a Populus nigra hydrolysate reaction containing a commercial cellulase mixture (Celluclast 1.5L and Novozyme 188) showed a stimulatory effect on reducing sugar production. AgEG is a good candidate for applications that convert lignocellulosic biomass to biofuels and chemicals. 相似文献
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Priyadharshini Ramachandran Zongpei Zhao Raushan Singh Saurabh Sudha Dhiman Joon-Ho Choi Dongwook Kim Jung-Rim Haw Jung-Kul Lee 《Bioprocess and biosystems engineering》2014,37(9):1817-1824
A highly efficient β-1,4-mannanase-secreting strain, Pholiota adiposa SKU0714, was isolated and identified on the basis of its morphological features and sequence analysis of internal transcribed spacer rDNA. P. adiposa β-1,4-mannanase was purified to homogeneity from P. adiposa culture supernatants by one-step chromatography on a Sephacryl gel filtration column. P. adiposa β-1,4-mannanase showed the highest activity toward locust bean gum (V max = 1,990 U/mg protein, K m = 0.12 mg/mL) ever reported. Its internal amino acid sequence showed homology with hydrolases from the glycoside hydrolase family 5 (GH5), indicating that the enzyme is a member of the GH5 family. The saccharification of commercial mannanase and P. adiposa β-1,4-mannanase-pretreated rice straw by Celluclast 1.5L (Novozymes) was compared. In comparison with the commercial Novo Mannaway® (113 mg/g-substrate), P. adiposa β-1,4-mannanase-pretreated rice straw released more reducing sugars (141 mg/g-substrate). These properties make P. adiposa β-1,4-mannanase a good candidate as a new commercial β-1,4-mannanase to improve biomass pretreatment. 相似文献
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Background
The potential to use data on family history of premature disease to assess disease risk is increasingly recognised, particularly in scoring risk for coronary heart disease (CHD). However the quality of family health information in primary care records is unclear.Aim
To assess the availability and quality of family history of CHD documented in electronic primary care recordsDesign
Cross-sectional studySetting
537 UK family practices contributing to The Health Improvement Network database.Method
Data were obtained from patients aged 20 years or more, registered with their current practice between 1st January 1998 and 31st December 2008, for at least one year. The availability and quality of recorded CHD family history was assessed using multilevel logistic and ordinal logistic regression respectively.Results
In a cross-section of 1,504,535 patients, 19% had a positive or negative family history of CHD recorded. Multilevel logistic regression showed patients aged 50–59 had higher odds of having their family history recorded compared to those aged 20–29 (OR:1.23 (1.21 to 1.25)), however most deprived patients had lower odds compared to those least deprived (OR: 0.86 (0.85 to 0.88)). Of the 140,058 patients with a positive family history recorded (9% of total cohort), age of onset was available in 45%; with data specifying both age of onset and relative affected available in only 11% of records. Multilevel ordinal logistic regression confirmed no statistical association between the quality of family history recording and age, gender, deprivation and year of registration.Conclusion
Family history of CHD is documented in a small proportion of primary care records; and where positive family history is documented the details are insufficient to assess familial risk or populate cardiovascular risk assessment tools. Data capture needs to be improved particularly for more disadvantaged patients who may be most likely to benefit from CHD risk assessment. 相似文献35.
Virulent tubercle bacilli inhibit apoptosis to establish a safe environment within the host cells. Here, we report that NF-kappaB dependent antiapoptotic protein bfl-1/A1 plays an important role in this process. Both virulent and avirulent mycobacteria bearing THP-1 cells expressed considerable amount of bfl-1/A1 after 4 h of infection. However, after 48 h of infection, bfl-1/A1 expression was evident only in Mycobacterium tuberculosis H37Rv but not in M. tuberculosis H37Ra infected cells. When parallel experiments were performed with Human monocyte-derived macrophages (MDMs), differential expression of bfl-1/A1 mRNA was observed in case of M. tuberculosis H37Rv and M. tuberculosis H37Ra infection. siRNA mediated inhibition of bfl-1/A1 induced apoptosis in M. tuberculosis H37Rv infected THP-1 and MDMs. Reduction in intracellular mycobacterial growth was observed in bfl-1/A1 siRNA transfected, M. tuberculosis H37Rv infected THP-1 cells. Enhancement of phagosome-lysosome fusion was observed in bfl-1/A1 siRNA treated and M. tuberculosis H37Rv infected THP-1 cells. These results clearly indicated that differential expression of bfl-1/A1 in M. tuberculosis H37Rv and M. tuberculosis H37Ra infected THP-1 cells probably account for the difference in infection outcome. 相似文献
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Balraj Singh Anna Shamsnia Milan R. Raythatha Ryan D. Milligan Amanda M. Cady Simran Madan Anthony Lucci 《PloS one》2014,9(10)
A major obstacle in developing effective therapies against solid tumors stems from an inability to adequately model the rare subpopulation of panresistant cancer cells that may often drive the disease. We describe a strategy for optimally modeling highly abnormal and highly adaptable human triple-negative breast cancer cells, and evaluating therapies for their ability to eradicate such cells. To overcome the shortcomings often associated with cell culture models, we incorporated several features in our model including a selection of highly adaptable cancer cells based on their ability to survive a metabolic challenge. We have previously shown that metabolically adaptable cancer cells efficiently metastasize to multiple organs in nude mice. Here we show that the cancer cells modeled in our system feature an embryo-like gene expression and amplification of the fat mass and obesity associated gene FTO. We also provide evidence of upregulation of ZEB1 and downregulation of GRHL2 indicating increased epithelial to mesenchymal transition in metabolically adaptable cancer cells. Our results obtained with a variety of anticancer agents support the validity of the model of realistic panresistance and suggest that it could be used for developing anticancer agents that would overcome panresistance. 相似文献
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Recent trends and advancements in microbial tannase-catalyzed biotransformation of tannins: a review
The outburst of green biotechnology has facilitated a substantial upsurge in the usage of enzymes in a plethora of industrial bioconversion processes. The tremendous biocatalytic potential of industrial enzymes provides an upper edge over chemical technologies in terms of safety, reusability, and better process control. Tannase is one such enzyme loaded with huge potential for bioconversion of hydrolysable tannins to gallic acid. Tannins invariably occur in pteridophytes, gymnosperms, and angiosperms and predominately cumulate in plant parts like fruits, bark, roots, and leaves. Furthermore, toxic tannery effluents from various tanneries are loaded with significant levels of tannins in the form of tannic acid. Tannase can be principally employed for debasing the tannins that predominately occur in the toxic tannery effluents thus providing a relatively much cheaper measure for their biodegradation. Over the years, microbial tannase-catalyzed tannin degradation has gained momentum. The plentious availability of tannin-containing agro- and industrial waste paves a way for efficient utilization of microbial tannase for tannin degradation eventually resulting into gallic acid production. Gallic acid has received a great deal of attention as a molecule of enormous therapeutic and indusrial potential. The current worldwide demand of gallic acid is 8000 t per annum. As a matter of fact, bioconversion of tannins into gallic acid through fermentation has not been exploited completely. This necessitates further studies for development of more efficient, economical, productive processes and improved strains for gallic acid production so as to meet its current demand. 相似文献
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Nadeem Siddiqui Simran Asawa Bhaskar Birru Ramaraju Baadhe Sreenivasa Rao 《Molecular biotechnology》2018,60(7):506-532
Biomaterial-based scaffolds are important cues in tissue engineering (TE) applications. Recent advances in TE have led to the development of suitable scaffold architecture for various tissue defects. In this narrative review on polycaprolactone (PCL), we have discussed in detail about the synthesis of PCL, various properties and most recent advances of using PCL and PCL blended with either natural or synthetic polymers and ceramic materials for TE applications. Further, various forms of PCL scaffolds such as porous, films and fibrous have been discussed along with the stem cells and their sources employed in various tissue repair strategies. Overall, the present review affords an insight into the properties and applications of PCL in various tissue engineering applications. 相似文献