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Order Amarillovirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
Mason et al. (1989) expressed in E. coli antigenic fragments of the JEV protein E to define the boundaries of an antigenic domain that contained the binding sites for monoclonal antibodies. Two fragments of the protein E were expressed in E. coli by Chia et al. (2001). Wu et al. (2003) obtained a soluble recombinant protein when the EDIII domain of the protein E was fused to thioredoxin. Lin et al. (2008) got in E. coli the EDIII domain corresponding to the E protein aa residues 298–399 without any fusions.
Marine Fungi-Derived Secondary Metabolites: Potential as Future Drugs for Health Care
Published in Hafiz Ansar Rasul Suleria, Megh R. Goyal, Health Benefits of Secondary Phytocompounds from Plant and Marine Sources, 2021
Syed Shams Ul Hassan, Hui-Zi Jin, Abdur Rauf, Saud Bawazeer, Hafiz Ansar Rasul Suleria
Two meroterpenoids (Austalide S (image 56 in Figure 8.4) and Austalide U (image 57 in Figure 8.4)) were isolated from the endophytic fungus (Aspergillus aureolatus) that was obtained from unidentified sponge collected from Xiasha islands in China [46]. Two asteltoxin-containing dimers (diasteltoxins A (image 58 in Figure 8.4) and diasteltoxins B (image 59 in Figure 8.4)) were also isolated from the sponge-derived mutated strain of Emericella variecolor fungus by means of chemical elicitation. The Diethyl sulfate was used as a chemical elicitor to activate the sleeping genes of fungus strain. These diasteltoxins A and B were not observed in normal growth of the current strain but were activated as novel compounds by means of chemical elicitation. All four compounds were examined for anti-cancer potential. The diasteltoxins A and B exhibited weak inhibition against the growth of breast cancer (MCF) with IC50 values of 73 µM and 127 µM and cell lung cancer (H1299) cell lines with IC50 values of 188 µM, and 164 µM, respectively. Furthermore, all diasteltoxins A and B significantly inhibited thioredoxin reductase (TrxR) with IC50 values of 12.8 ±0.8 µM and 11.1 ± 0.2 µM, respectively.
New Chemical Scaffolds to Selectively Target the Trypanothione Metabolism
Published in Venkatesan Jayaprakash, Daniele Castagnolo, Yusuf Özkay, Medicinal Chemistry of Neglected and Tropical Diseases, 2019
LmTXNPx is a toroidal decamer formed by 5 dimers that are the active physiological units of the enzyme (Figure 6). As in TXN and in other proteins of the thioredoxin superfamily, the fold of LmTXNPx monomers consists of a seven-stranded twisted β-sheet, surrounded by four α-helices and two short 310-helices, with the peroxidatic cysteine Cys52 (Cp) located at the N-terminus of the α-helix (a1), in a position similar to that of Cys43 in TXN, while the resolving cysteine (Cys173, Cr’) and the whole C-terminal part of the protein are disordered and not visible in the structure of the protein in the reduced form (LU).
Cancer cell membrane camouflaging mesoporous nanoplatform interfering with cellular redox homeostasis to amplify photodynamic therapy on oral carcinoma
Published in Journal of Drug Targeting, 2023
Qing Wu, Haoran Ning, Huaiji Wang, Hongfei Hua, Wa Li, Bin Xu
With the development of nanotechnology, the selective accumulation of photosensitizers in the tumour has been further enhanced by liposomes, microcapsules, and other nanodrug delivery platforms [4–6]. However, the efficacy of PDT is still limited by the insufficient production and inefficient utilisation of ROS in tumours [7–9]. The existence of redox homeostasis makes cancer cells resistant to the produced ROS during PDT [10]. Thioredoxin reductase (TrxR) regulates the thiol/disulphide bond balance between proteins through disulphide reductase activity, and maintaining the dynamic balance between the reducing capacity and oxidative stress of cells is a key factor to ensure homeostasis [11]. Elevated levels of thioredoxin system proteins and decreased levels of thioredoxin-interacting protein (TNXIP) are involved in various cancers, including oral carcinoma [12]. Trx expression levels have been found to be significantly associated with the lower 5-year survival of patients with oral carcinoma patients [12,13]. Redox imbalance can sensitise cells to ROS effects, leading to inhibition of tumour cell proliferation [14]. Therefore, creating redox imbalance has been a key goal in cancer therapy.
YjbH mediates the oxidative stress response and infection by regulating SpxA1 and the phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS) in Listeria monocytogenes
Published in Gut Microbes, 2021
Changyong Cheng, Xiao Han, Jiali Xu, Jing Sun, Kang Li, Yue Han, Mianmian Chen, Houhui Song
Bacteria maintain the cytosolic redox status largely by using redox-regulating thiol molecules such as glutathione and the dicysteine proteins thioredoxin and glutaredoxin.13 At the expense of NADPH, glutathione is maintained in a reduced state by glutathione reductase, and thioredoxin is kept reduced by thioredoxin reductase.14 Many Gram-positive bacteria mainly employ low-molecular-weight thiols, thioredoxin, and alternative thioredoxin-based enzymes as antioxidant systems.15,16 The thioredoxin family contains a common structural fold (the Trx domain) and is involved in cellular defense against oxidative stress caused by reactive oxygen species (ROS).17 Thioredoxin is the major cellular disulfide reductase in cells, which can provide a highly reducing environment and then function as an effector to facilitate correct oxidative protein folding. In L. monocytogenes, PrfA, a cAMP receptor protein (Crp) family transcriptional regulator that is essential for virulence gene expression and pathogenesis,18 is exclusively activated in the cytosol of host cells. The glutathione generated by bacteria or derived from host cells is the essential small-molecule cofactor of PrfA. Glutathione allosterically binds to PrfA, thereby increasing its activity regarding inducing target genes.19,20
Untargeted proteomics reveals upregulation of stress response pathways during CHO-based monoclonal antibody manufacturing process leading to disulfide bond reduction
Published in mAbs, 2021
Seo-Young Park, Susan Egan, Anthony J. Cura, Kathryn L. Aron, Xuankuo Xu, Mengyuan Zheng, Michael Borys, Sanchayita Ghose, Zhengjian Li, Kyongbum Lee
A recombinant CHO cell line expressing an IgG molecule was used to investigate the effects of cell culture process on the susceptibility of mAb disulfide bond reduction in the HCCF. We previously observed15 that culturing the cells in the same vessel for N-1 seed and fed-batch production (‘rolled’ bioreactor condition) resulted in disulfide reduction-susceptible HCCF. In contrast, transferring the N-1 seed culture into a fresh vessel for fed-batch production (‘control’ bioreactor condition) resulted in reduction-free HCCF. In general, we observed that disulfide reduction-susceptibility correlated with the expression and activity of the thioredoxin system. The growth profiles and antibody titers of these two bioreactor conditions were indistinguishable. However, we observed significant differences in several metabolic indicators, including the ratio of extracellular lactate to pyruvate, GAPDH expression, 6-phosphogluconate dehydrogenase expression, and glucose-6-phosphate dehydrogenase activity, suggesting a metabolic shift to the pentose phosphate pathway in disulfide reduction-susceptible HCCF.15