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111.

Background  

NEP1-like proteins (NLPs) are a novel family of microbial elicitors of plant necrosis. Some NLPs induce a hypersensitive-like response in dicot plants though the basis for this response remains unclear. In addition, the spatial structure and the role of these highly conserved proteins are not known.  相似文献   
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Background: A plant powder called “Maras powder” is widely used instead of cigarette smoking in the South-Eastern region of Turkey. It has been confirmed that this powder comprises tobacco Nicotiana rustica L. Methods: The aim of this study was to assess the effect of Maras powder and cigarette smoking on the P16 promotor hypermethylation. Twenty-two Maras powder users (Group I), 12 cigarette smokers (Group II), and 16 healthy controls who neither smoked nor used Maras powder (Group III) were included in the study. Hypermethylation of the P16 gene was examined using methylation-specific PCR (MSP) method in the blood of the three groups. Results: Aberrant P16 methylation was found in 7 of the 22 (31.8%) in Group I, in 3 of 12 (25%) in Group II, and in 1 of 16 (6.25%) in Group III. Conclusion: Maras powder may be as harmful as cigarette smoking, leading to hypermethylation in P16 and warrants detailed studies on this subject.  相似文献   
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In this study, pepsin from turkey proventriculus was purified, and its biochemical properties examined. Initially, the turkey proventriculus (stomach) was mixed with 10% NaCl (1∶2, w/v) and extracted by centrifugation to produce a crude extract. The partial purification of the extract was carried out using Sephadex G-50 resin in gel filtration column chromatography. The fractions obtained by gel filtration were analyzed for milk clotting activity (MCA), protein content, proteolytic activity (PA), purification factor (PF), and SDS-PAGE electrophoresis was also performed. The enzyme was purified 207-fold with a recovery of 36%. The first 4 fractions did not have any activities; fractions 7, 8, and 9 exhibited the highest levels of milk clotting and proteolytic activity. The electrophoretic patterns revealed that further purification steps should be applied for better results.  相似文献   
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Heterocyclic compounds are found in a variety of drug molecules, and bioactive natural products. 4-Thiazolidinones (4-TZDs), which represent an important class of heterocyclic compounds, are of great interest today with their diverse bioactivities. In this study, ten novel 4-TZD derivatives ( C1 – C10 ) were synthesized, characterized by spectroscopic techniques, and their genotoxic, and antigenotoxic properties were investigated in vitro using the Ames Salmonella/microsome mutagenicity assay in the concentration range of 0.2–1.0 mM/plate. The results revealed that none of the compounds were mutagenic on the three different Salmonella typhimurium strains up to the highest concentration tested. Furthermore, in our study, C1 , C4 , C6 , and C9 showed significant, ranging from moderate to strong, antigenotoxic effects against mutagen-induced DNA damage at relatively higher doses. Among these, C4 had the best potential to inhibit the number of revertant colonies induced by 9-aminoacridine (9-AA), with a maximum inhibition rate of 47.9 % for 1.0 mM/plate. As a result, preliminary knowledge about the safety of the use of ten novel synthesized 4-TZD compounds likely to exhibit many bioactivities was obtained in this study. In addition, the significant in vitro antimutagenic activity of some derivatives increases the importance of studies for the development of new pharmacological agents for cancer prevention.  相似文献   
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Industrial biotechnology employs the controlled use of microorganisms for the production of synthetic chemicals or simple biomass that can further be used in a diverse array of applications that span the pharmaceutical, chemical and nutraceutical industries. Recent advances in metagenomics and in the incorporation of entire biosynthetic pathways into Saccharomyces cerevisiae have greatly expanded both the fitness and the repertoire of biochemicals that can be synthesized from this popular microorganism. Further, the availability of the S. cerevisiae entire genome sequence allows the application of systems biology approaches for improving its enormous biosynthetic potential. In this review, we will describe some of the efforts on using S. cerevisiae as a cell factory for the biosynthesis of high-value natural products that belong to the families of isoprenoids, flavonoids and long chain polyunsaturated fatty acids. As natural products are increasingly becoming the center of attention of the pharmaceutical and nutraceutical industries, the use of S. cerevisiae for their production is only expected to expand in the future, further allowing the biosynthesis of novel molecular structures with unique properties.  相似文献   
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The main objectives of the study were to produce inulinase from carob extract by Aspergillus niger A42 (ATCC 204447) and to model the inulinase fermentation in the optimum carob extract-based medium. In the study, carob extract was used as a novel and renewable carbon source in the production of A. niger inulinase. For medium optimization, eight different variables including initial sugar concentration (°Bx), (NH4)2HPO4, MgSO4.7H2O, KH2PO4, NH4NO3, yeast extract, peptone, and ZnSO4.7H2O were employed. After fermentations, optimum medium composition contained 1% yeast extract in 5°Bx carob extract. As a result of the fermentation, the maximum inulinase activity, maximum invertase-type activity, I/S ratio, maximum inulinase- and invertase-type activity rates, maximum sugar consumption rate, and sugar utilization yield were 1507.03 U/ml, 1552.86 U/ml, 0.97, 175.82 and 323.76 U/ml/day, 13.26 g/L/day, and 98.52%, respectively. Regarding mathematical modeling, the actual inulinase production and sugar consumption data were successfully predicted by Baranyi and Cone models based on the model evaluation and validation results and the predicted kinetic values, respectively. Consequently, this was the first report in which carob extract was used in the production of inulinase as a carbon source. Additionally, the best-selected models can serve as universal equations in modeling the inulinase production and sugar consumption in shake flask fermentation with carob extract medium.  相似文献   
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