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排序方式: 共有954条查询结果,搜索用时 46 毫秒
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Justyna Sulej Monika Osińska-Jaroszuk Magdalena Jaszek Marcin Grąz Jolanta Kutkowska Anna Pawlik Agata Chudzik Renata Bancerz 《Fungal biology》2019,123(12):875-886
Cellobiose dehydrogenase (CDH, EC 1.1.99.18) is a glycoprotein having many biotechnological applications. In the present study, CDHs isolated from Phlebia lindtneri (PlCDH), Phanerochaete chrysosporium (PchCDH), Cerrena unicolor (CuCDH), and Pycnoporus sanguineus (PsCDH) were studied the first time for their ability to generate antioxidant and antimicrobial agents. The aim of the research was to evaluate the antioxidant and antimicrobial activity of systems composed of four CDHs and lactose or cellobiose as a reaction substrate. The free radical scavenging effect of free and immobilised enzymes was evaluated using the DPPH method. The lowest values of EC50 (10.04 ± 0.75 /ml) was noted for PlCDH/lactose and for PlCDH/cellobiose (12.06 ± 1.35 /ml). The EC50value reached 12.6 ± 1.51 /ml in the case of PsCDH/lactose and 15.96 ± 1.35 for PsCDH. The CDH preparations were also effectively immobilised in alginate (the immobilisation efficiency expressed as a protein yield ranged from 61.6 to 100 %). The operational stability expressed as a scavenging effect showed the possibility of using the alginate beads 4 times. Both the free and immobilised CDHs as well as the CDH/substrate were tested against Gram-negative Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Gram-positive Staphylococcus aureus ATCC 25923 bacteria. All samples, except PlCDH, were potentially effective in suppression of bacterial growth. The highest percentage of inhibition (100 %) was obtained for S. aureus bacteria using PsCDH and PchCDH with lactose as a substrate, whereas a slightly lesser effect was observed for E. coli and P. aeruginosa bacterial cells, i.e. 64.1 % and 86.5 % (PsCDH) and 94.1 % and 41.4 % (PchCDH), respectively. Furthermore, the concentrations of the reaction products (aldonic acids and hydrogen peroxide) were quantified and the surface morphology of the alginate beads was analysed using SEM visualisation. 相似文献
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V. V. Shumyantseva T. V. Bulko Yu. O. Rudakov G. P. Kuznetsova N. F. Samenkova A. V. Lisitsa I. I. Karuzina A. I. Archakov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2007,1(4):327-333
Direct electron transfer has been demonstrated between cytochrome P450 2B4 (CYP2B4), P450 1A2 (CYP1A2), sterol 14α-demethylase (CYP51MT) and screen printed graphite electrodes, modified by gold nanoparticles and didodecyldimethyl ammonium bromide (DDAB). The proposed method for preparation of enzymatic nanostructured electrodes may be used for electrodetection of this hemoprotein provided that 2–200 pmol P450 per electrode has been adsorbed. Electron transfer, direct electrochemical reduction and interaction with P450 substrates (oxygen, benzphetamine, lanosterol) and inhibitor ketoconazole were analyzed using cyclic voltammetry (CV), square wave (SWV) or differential pulse (DPV) voltammetry, and amperometry. 相似文献
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《遗传学报》2022,49(7):645-653
Li-Fraumeni syndrome (LFS), a rare autosomal-dominant inheritance condition, is associated with a family cancer history as well as pathogenic/likely-pathogenic TP53 germline variants (P/LP TP53 GV). The current clinical methods for detecting LFS are limited. Here, we retrospectively investigate P/LP TP53 GV among Chinese cancer patients by next-generation sequencing and evaluate its relationship with a family cancer history. A total of 270 out of 19,226 cancer patients have TP53 GV, including 53 patients with P/LP TP53 GV. Patients with P/LP TP53 GV are mainly found in male with glioma, lung cancer or sarcoma. The median age of diagnosis for P/LP TP53 GV patients is significantly lower than that of non-P/LP TP53 GV patients (31-years vs. 53-years; P < 0.01). One LFS patient and 3 Li-Fraumeni-like syndrome (LFL) patients are among the 26 followed-up P/LP TP53 GV patients. Among 25 types of P/LP TP53 GV, the highest variant frequencies occurred at codon 175 and 248. p.M237I, p.R158H, p.C238Y and p.C275R, are firstly identified among the Chinese LFS/LFL patients. This study reports the (P/LP) TP53 GV characteristics of Chinese pan-cancer patients. These findings suggest analyzing the P/LP TP53 GV in cancer patients is an effective strategy for identifying cancer predisposition syndrome. 相似文献
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Xu Z Escamilla-Treviño L Zeng L Lalgondar M Bevan D Winkel B Mohamed A Cheng CL Shih MC Poulton J Esen A 《Plant molecular biology》2004,55(3):343-367
In plants, Glycoside Hydrolase (GH) Family 1 -glycosidases are believed to play important roles in many diverse processes including chemical defense against herbivory, lignification, hydrolysis of cell wall-derived oligosaccharides during germination, and control of active phytohormone levels. Completion of the Arabidopsis thalianagenome sequencing project has enabled us, for the first time, to determine the total number of Family 1 members in a higher plant. Reiterative database searches revealed a multigene family of 48 members that includes eight probable pseudogenes. Manual reannotation and analysis of the entire family were undertaken to rectify existing misannotations and identify phylogenetic relationships among family members. Forty-seven members (designated BGLU1 through BGLU47) share a common evolutionary origin and were subdivided into approximately 10 subfamilies based on phylogenetic analysis and consideration of intron–exon organizations. The forty-eighth member of this family (At3g06510; sfr2) is a -glucosidase-like gene that belongs to a distinct lineage. Information pertaining to expression patterns and potential functions of Arabidopsis GH Family 1 members is presented. To determine the biological function of all family members, we intend to investigate the substrate specificity of each mature hydrolase after its heterologous expression in the Pichia pastoris expression system. To test the validity of this approach, the BGLU44-encoded hydrolase was expressed in P. pastoris and purified to homogeneity. When tested against a wide range of natural and synthetic substrates, this enzyme showed a preference for -mannosides including 1,4--D-mannooligosaccharides, suggesting that it may be involved in A. thaliana in degradation of mannans, galactomannans, or glucogalactomannans. Supporting this notion, BGLU44 shared high sequence identity and similar gene organization with tomato endosperm -mannosidase and barley seed -glucosidase/-mannosidase BGQ60. 相似文献