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1دورية أكاديمية
المؤلفون: Ming-Xing Zhang, Kai-Li Zheng, Ai-Guo Tang, Xiao-Xia Hu, Xin-Xin Guo, Chao Wu, Yuan-Yuan Cheng
المصدر: Microorganisms, Vol 9, Iss 11, p 2316 (2021)
مصطلحات موضوعية: YgfY, Shewanella, toxin–antitoxin, succinate dehydrogenase, flavinylation, Biology (General), QH301-705.5
الوصف: YgfY(SdhE/CptB) is highly conserved while has controversial functions in bacteria. It works as an antitoxin and composes a type IV toxin–antitoxin system with YgfX(CptA) typically in Escherichia coli, while functions as an flavinylation factor of succinate dehydrogenase and fumarate reductase typically in Serratia sp. In this study, we report the contribution of YgfY in Shewanella oneidensis MR-1 to tolerance of low temperature and nitrite. YgfY deficiency causes several growth defects of S. oneidensis MR-1 at low temperature, while YgfX do not cause a growth defect or morphological change of S. oneidensis MR1-1 and E. coli. YgfY do not interact with FtsZ and MreB nor with YgfX examined by bacterial two-hybrid assay. YgfY effect on growth under low temperature is not attributed to succinate dehydrogenase (SDH) because a mutant without SDH grows comparably with the wild-type strain in the presence of succinate. The ygfY mutant shows impaired tolerance to nitrite. Transcription of nitrite reductase and most ribosome proteins is significantly decreased in the ygfY mutant, which is consistent with the phenotypes detected above. Effects of YgfY on growth and nitrite tolerance are closely related to the RGXXE motif in YgfY. In summary, this study demonstrates pleiotropic impacts of YgfY in S. oneidensis MR-1, and sheds a light on the physiological versatility of YgfY in bacteria.
وصف الملف: electronic resource
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المؤلفون: Yu Zhen Liu, Zheng Wang, Kai Li Zheng, Jie Min Cheng
المصدر: Materials Science Forum. 1060:169-176
مصطلحات موضوعية: Mechanics of Materials, Mechanical Engineering, General Materials Science, Condensed Matter Physics
الوصف: Black Carbon (BC) is a solid material obtainable from the remnants of incomplete burning of biological organisms or fossil fuels, which benefits pollution alleviation and soil amendment. In this study MBC was prepared using acidic potassium permanganate for inactivating heavy metal in soils. The specific surface area and pore volume of BC and MBC were measured by nitrogen adsorption and the space around the black carbon particles was observed by Scanning Electron Microscopy (SEM). The contents of carboxyl, ester and phenol hydroxyl group on their surface have been determined. The effect on availability of Cu in soils and soil enzyme activity of MBC was also investigated. Scanning electron microscopy analysis of MBC demonstrated large micropores with looser aggregate structure. MBC featured a higher surface area (956.88m2·g-1), larger average pore size and pore volume than BC, which can improve its excellent adsorption ability. Using as a soil heavy metal passivator, MBC reduced the available content of copper in three soils significantly and MBC has the best passivation effect on copper in cinnamon soil. Comparison of the enzyme activities in three soils amended with MBC under constant moisture conditions revealed that MBC increased the activities of catalase, urease in different degrees and inhibited the activities of dehydrogenase in three soils. These findings suggest that MBC has a strong passivation ability to Cu and would be applied to the remediation of copper contaminated soil.
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::d731bbcc7b37af488ac18e2a94a3ff95Test
https://doi.org/10.4028/p-p6558eTest
النص الكامل