http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Construction and analysis of Sip1Aa insecticidal protein random recombination library
Ding Yue-ming,Wang Jing,Wang Lin,Gao Ji-Guo,Liu Rong-Mei,Li Hai-Tao 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.2
The Sip1Aa protein from Bacillus thuringiensis is highly toxic to Colaphellus bowringi Baly. In order to obtain mutant proteins with higher insecticidal activity, a random recombinant library of Sip1Aa protein was con structed using error-prone PCR. A total number of 100 positive transformants were randomly selected for sequence determination, and 25 mutants (M1 to M25) were selected and expressed the respective Sip1Aa mu tants. These Sip1Aa variants had a total of 29 base mutations, with an average of 1.2 base mutations per mutant. Compared with that of the wild-type Sip1Aa protein, the insecticidal activity of the mutants M1 (A31G, Y118C, D227E), M5 (K168R) and M21 (I307T) was significantly decreased, with and LC 50 values 4 to 6 times higher than the Sip1Aa protein. The mutant M8 (R174S) showed increase in the insecticidal activity against the Colaphellus bowringi Baly was obtained, with an LC 50 value 4-fold less than the Sip1Aa protein. The results of this study provide reference for the molecular modification of Sip1Aa protein and the study of key sites of its insecticidal activity.
( Bo Xu ),( Li Ming Dai ),( Jun Jun Li ),( Meng Deng ),( Hua Biao Miao ),( Jun Pei Zhou ),( Yue Lin Mu ),( Qian Wu ),( Xiang Hua Tang ),( Yun Juan Yang ),( Jun Mei Ding ),( Nan Yu Han ),( Zun Xi Huang 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.1
Xylanases sourced from different bacteria have significantly different enzymatic properties. Therefore, studying xylanases from different bacteria is important to their applications in different fields. A potential xylanase degradation gene in Massilia was recently discovered through genomic sequencing. However, its xylanase activity remains unexplored. This paper is the first to report a xylanase (XynRBM26) belonging to the glycosyl hydrolase family (GH10) from the genus Massilia. The gene encodes a 383-residue polypeptide (XynRBM26) with the highest identity of 62% with the endoxylanase from uncultured bacterium BLR13. The XynRBM26 expressed in Escherichia coli BL21 is a monomer with a molecular mass of 45.0 kDa. According to enzymatic characteristic analysis, pH 5.5 is the most appropriate for XynRBM26, which could maintain more than 90% activity between pH 5.0 and 8.0. Moreover, XynRBM26 is stable at 37°C and could maintain at least 96% activity after being placed at 37°C for 1 h. This paper is the first to report that GH10 xylanase in an animal gastrointestinal tract (GIT) has salt tolerance, which could maintain 86% activity in 5 M NaCl. Under the optimum conditions, Km, Vmax, and kcat of XynRBM26 to beechwood xylan are 9.49 mg/ml, 65.79 μmol/min/mg, and 47.34 /sec, respectively. Considering that XynRBM26 comes from an animal GIT, this xylanase has potential application in feedstuff. Moreover, XynRBM26 is applicable to high-salt food and seafood processing, as well as other high-salt environmental biotechnological fields, because of its high catalytic activity in high-concentration NaCl.
Biotransformation of natural polyacetylene in red ginseng by Chaetomium globosum
Wang, Bang-Yan,Yang, Xue-Qiong,Hu, Ming,Shi, Li-Jiao,Yin, Hai-Yue,Wu, Ya-Mei,Yang, Ya-Bin,Zhou, Hao,Ding, Zhong-Tao The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6
Background: Fermentation has been shown to improve the biological properties of plants and herbs. Specifically, fermentation causes decomposition and/or biotransformation of active metabolites into high-value products. Polyacetylenes are a class of polyketides with a pleiotropic profile of bioactivity. Methods: Column chromatography was used to isolate compounds, and extensive NMR experiments were used to determine their structures. The transformation of polyacetylene in red ginseng (RG) and the production of cazaldehyde B induced by the extract of RG were identified by TLC and HPLC analyses. Results: A new metabolite was isolated from RG fermented by Chaetomium globosum, and this new metabolite can be obtained by the biotransformation of polyacetylene in RG. Panaxytriol was found to exhibit the highest antifungal activity against C. globosum compared with other major ingredients in RG. The fungus C. globosum cultured in RG extract can metabolize panaxytriol to Metabolite A to survive, with no antifungal activity against itself. Metabolites A and B showed obvious inhibition against NO production, with ratios of 42.75 ± 1.60 and 63.95 ± 1.45% at 50 µM, respectively. A higher inhibitory rate on NO production was observed for Metabolite B than for a positive drug. Conclusion: Metabolite A is a rare example of natural polyacetylene biotransformation by microbial fermentation. This biotransformation only occurred in fermented RG. The extract of RG also stimulated the production of a new natural product, cazaldehyde B, from C. globosum. The lactone in Metabolite A can decrease the cytotoxicity, which was deemed to be the intrinsic activity of polyacetylene in ginseng.
Research on Control Strategy of Hybrid Energy Storage System with Optical Storage Microgrid
Zhu Zuo-Bin,Sun Shu-Min,Ding Yue-Ming,Huang Shao-Ping 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4
With the aim of improving the robustness of the hybrid energy storage system(HESS) and avoiding overcharging and reasonably managing state of charge (SOC), this paper proposed a HESS control strategy employing integral backstepping (IBS) method based on SOC. Firstly, on the basis of the hybrid energy storage control strategy of conventional filtering technology (FT), the current inner loop PI controller was changed into an controller employing IBS method to improve the robustness shown by the energy storage system (ESS) against system parameter perturbation or external disturbance. The current controller of the HESS employing inner loop integral backstepping method was designed and the Lyapunov stability was proven. Secondly, to avoid overcharging and over-discharging of the HESS and to reasonably manage SOC, an energy management strategy based on SOC was proposed to generate the current reference value of the inner loop controller employing integral backstepping method, and the energy management strategy based on SOC was designed as well. Finally, the simulation model of the HESS employing integrated backstepping method based on SOC was established, and the feasibility of this method was verified through simulation. It was shown by the results obtained from the simulation that the HESS control strategy employing integrated backstepping method based on SOC had greater anti-interference ability and improved the robustness of the system, in comparison with the control strategy of FT (PI) and FT (IBS) hybrid energy storage. In the meanwhile, the upper and lower limits of SOC of the ESS are supposed to be managed to avoid overcharging and over-discharging and to extend the life of the ESS.