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101.
The tumor suppressor PTEN is necessary for human Sprouty 2-mediated inhibition of cell proliferation
Edwin F Singh R Endersby R Baker SJ Patel TB 《The Journal of biological chemistry》2006,281(8):4816-4822
Sprouty family proteins are novel regulators of growth factor actions. Human Sprouty 2 (hSPRY2) inhibits the proliferation of a number of different cell types. However, the mechanisms involved in the anti-proliferative actions of hSPRY2 remain to be elucidated. Here we have demonstrated that hSPRY2 increases the amount of the tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and decreases its phosphorylation. The resultant increase in PTEN activity is reflected in decreased activation of Akt by epidermal growth factor and serum. Consistent with increased PTEN activity, in hSPRY2-expressing cells, the progression of cells from the G1 to S phase is decreased. By using PTEN null primary mouse embryonic fibroblasts and their isogenic controls as well as small interfering RNA against PTEN, we demonstrated that PTEN is necessary for hSPRY2 to inhibit Akt activation by epidermal growth factor as well as cell proliferation. Overall, we concluded that hSPRY2 mediates its anti-proliferative actions by altering PTEN content and activity. 相似文献
102.
Xuankuo Xu David M. Didio Kirk J. Leister Sanchayita Ghose 《Biotechnology progress》2010,26(3):717-726
The use of chaotropic agents to recover functional monomeric material was investigated for the downstream purification of an Fc‐fusion protein containing high levels of high‐molecular weight (HMW) species. In batch studies, chaotropic agents irreversibly disaggregated a majority of the aggregated protein. An integrated processing mode, termed as on‐column disaggregation, was developed in which the protein was captured on Protein A chromatography and then a chaotropic agent was used to simultaneously elute the bound protein and disaggregate the HMW species. On‐column disaggregation process resulted in protein recoveries of >95% and aggregation reduction of ~50%. Analytical results are presented showing that the recovered monomeric material was comparable to the reference protein in biochemical, biophysical, and pharmacokinetic properties. The kinetic and molecular mechanisms governing protein aggregation and disaggregation will also be elucidated. For the Fc‐fusion protein studied here, incorporation of the disaggregation strategy in both batch and on‐column modes led to an increase of >10% in overall downstream yield. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 相似文献
103.
QSAR studies on series of pyrrolo[2,3-d]pyrimidine nucleoside analogues were performed for their adenosine kinase (AK) inhibitory activity using the Hansch approach. Significant correlations were obtained with hydrophobic parameter at position 'X'. Electronic and steric parameters on pyrimidine and pyrrole rings found to play an important role in the ligand-receptor interactions with the active sites of the enzyme. Presence of bulkier groups at 'X' and 'Y' positions seems to protect the title compounds from biodegradation, as is evident from their positive sterimol steric parameter B1 at these positions. 相似文献
104.
Two new studies have shown how regulation of microtubule dynamics by members of the kinesin superfamily may guard against errors in spindle assembly and chromosome segregation. 相似文献
105.
Vertical Profile of Phosphatase Activity in the Sundarban Mangrove Forest,North East Coast of Bay of Bengal,India 总被引:2,自引:0,他引:2
Impact of phosphate solubilizing bacteria along with soil phosphatase activity on phosphorous cycle was found to be quiet interesting in the Sundarban mangrove ecosystem. Soil phosphatase activity showed a decreasing pattern with increase in depth [soil phosphatase activity (μg pnp produced g?1 dry wt of soil) = 906.85 – 5.6316 Depth (cm)] from the deep forest region of the Sundarban forest ecosystem. Soil salinity showed a very little effect on soil phosphatase activity whereas soil temperature and pH was found to show significant impact on the soil phosphatase activity. This ensured that the microbes associated with phosphate mineralization present in the Sundarban forest ecosystem are more tolerant to fluctuation in salinity than that of temperature and pH. A direct correlation was perceptible between the number of phosphate solubilizing bacteria and phosphatase activity in the soil during the study period from 2007 to 2012. Soil phosphate concentration was found to be directly governed by the soil phosphatase activity [The regression equation is: avg PO4?3-P (μg g?1 dry wt of soil) = 0.0311 + 0.000606 soil phosphatase activity (μg pnp produced g?1 dry wt of soil); R2 = 63.2%, p < 0.001, n = 62]. 相似文献
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Significant increase in extracellular cellulase and hemicellulase activities was observed in the biosynthesis of cellulase enzyme in mixed culture fermentation of Trichoderma reesei D 1-6 and Aspergillus wentii Pt 2804 when the A. wentii inoculation was phased by 15 h. The optimal conditions of fermentation by the mixed culture have been established. Presence of mannanase has been found to affect the release as well as activity of cellulase enzyme produced in mixed culture. 相似文献
110.
Birendra Prasad Gupta Andrea Haselbeck Jerome H. Kim Florian Marks Tarun Saluja 《Annals of clinical microbiology and antimicrobials》2018,17(1):32