BIOTECHNOLOGY LETTERS
·
2016
·Vol. 38
·期 6
·1009-1013
·
IF 1.639
Kang Le,Bai Yajun,Cai Yujie,Zheng Xiaohui
Objectives To characterize a novel feruloyl esterase from Escherichia coli BL21 DE3. Results The gene encoding BioH was cloned and overexpressed in E. coli . The protein was purified and its catalytic activity was assessed. BioH exhibited feruloyl esterase activity toward a broad range of substrates, and the corresponding kinetic constants for the methyl ferulate, ethyl ferulate, and methyl p -coumarate substrates were: K
m
values of 0.48, 6.3, and 1.9 mM, respectively, and k
cat
/ K
m
values of 9.3, 3.8, and 3.8 mM −1 s −1 , respectively. Conclusions Feruloyl esterase from E. coli was expressed for the first time. BioH was confirmed to be a feruloyl esterase.
研究领域:
生物化学
·
微生物学
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2022
·
IF 4.885
Wenhao Qu,Yajun Bai,Tai-Ping Fan,Xiaohui Zheng,Yujie Cai
Lactobacillus reuteri DSM20016 has several aldo-keto reductases (AKRs), and they were heterologously expressed in E. coli BL21 (DE3) in this study. Subsequently, these AKRs were purified, and their enzymatic properties were investigated. It was found that these enzymes used NADPH as coenzyme and did not depend on metal ions. The optimum pH of these AKRs was a slightly acidic (AKR-1 and AKR-6: 5.5; AKR-3 and AKR-8: 6; AKR-2 and AKR-4: 6.5). These enzymes had a broad substrate spectrum and could convert a variety of aldehydes to alcohols; however, they did not catalyze the reverse reactions. All results showed that Lactobacillus reuteri had the ability to produce various volatile compounds, which allowed Lactobacillus reuteri to impart complex aroma to something.
研究领域:
微生物学
·
生物化学
·
酶学
·
食品科学
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DOI
高影响因子
TEXTILE RESEARCH JOURNAL
·
2017
·
IF 1.443
Ruijun Wang,Zhengchu Liu,Lifeng Cheng,Shengwen Duan,Xiangyuan Feng,Ke Zheng,Yi Cheng,Jie Zeng
Xylanase plays an important role in the hydrolysis of hemicellulose and has gained much attention in the field of biological degumming. The research for xylanases with cellulase-free and high activity for biological degumming has intensified in recent years. In the present research, heterologous expression of a novel endo-β-1,4-xylanase (GH30) from Dickeya dadantii DCE-01 in Escherichia coli BL21 (DE3) was reported. Biochemical characterization of the enzyme and a potential application in ramie biological degumming was discussed. The results showed that the xylanase gene consists of 1251 nucleotides, belonging to glycoside hydrolase family 30 (GH30). The optimal activity of the xylanase was observed at 50℃ and a pH value of 6.4. The Km and Vmax values for beechwood xylan were 14.25 mg/mL and 296.6 μmol/mg, respectively. The catalytic activity was enhanced by addition of 1 mM Cu2+, Ca2+, Mg2+, and K+. The recombinant enzyme was specific for xylan substrates. The enzyme exhibited hydrolytic activity toward ramie hemicellulose. The recombinant xylanase could be effectively applied to ramie degumming.
研究领域:
生物化学
·
生物技术
·
酶学
·
纺织科学
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DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Zehao Li,Wanying Wang,Guoguo Wang,Yingjie Feng,Yan Chen,Zhijian Li,Lulu Zhang,Jinchu Yang
Carvone has been widely used in pharmaceutical, food, cosmetic, and chemical industries due to its pleasant odor with high economic value and pharmacological activities. Carveol dehydrogenase is an enzyme that catalyzes the oxidation of carveol into carvone in the presence of NAD(P) + . In this study, two dehydrogenase genes from Klebsiella sp. O852 ( KlebADH1 and KlebADH2 ) were cloned and expressed in Escherichia coli BL21(DE3), and the purified enzymes were characterized for their biocatalytic properties. KlebADH1 and KlebADH2 displayed optimal catalytic activity at 40 °C and 30 °C, respectively, at pH 9. In addition to carveol, KlebADH1 had the potential to catalyze the oxidation of perillyl alcohol, nerol and geraniol, while borneol and geraniol could serve as potential substrates for KlebADH2. The substrate kinetic parameters of enzymes were performed by changing the concentration of carveol, and the results indicated that KlebADH2 exhibited a high affinity for carveol. Additionally, KlebADH1 and KlebADH2 were confirmed to possess carveol dehydrogenase activity through a double-enzyme-coupled (DEC) biotransformation system. The investigation of the biocatalytic properties of KlebADH1 and KlebADH2 laid a solid foundation for further study of carvone sustainable synthesis.
研究领域:
生物技术
·
酶学
·
化学工程
·
药学
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产品关联
DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2021
·
IF 6.291
Zhijian Ke,Qian Zhu,Wankui Jiang,Yidong Zhou,Mingliang Zhang,Mingli Jiang,Qing Hong
Carbaryl is the representative of carbamate insecticide. As an acetylcholinesterase inhibitor, it poses potential threat to humans and other non-target organisms. Agrobacterium sp. XWY-2, which could grow with carbaryl as the sole carbon source, was isolated and characterized. The carH gene, encoding a carbaryl hydrolase, was cloned from strain XWY-2 and expressed in Escherichia coli BL21 (DE3). CarH was able to hydrolyze carbamate pesticides including carbaryl, carbofuran, isoprocarb, propoxur and fenobucarb efficiently, while it hydrolyzed oxamyl and aldicarb poorly. The optimal pH of CarH was 8.0 and the optimal temperature was 30 ℃. The apparent K m and k cat values of CarH for carbaryl were 38.01 ± 2.81 μM and 0.33 ± 0.01 s −1 , respectively. The point mutation experiment demonstrated that His341, His343, His346, His416 and D437 are the key sites for CarH to hydrolyze carbaryl.
研究领域:
环境科学
·
微生物学
·
生物化学
·
酶学
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产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Wei Luo,Jiagui Hu,Jiapeng Lu,Huili Zhang,Xiaoping Wang,Yuantao Liu,Liqing Dong,Xiaobin Yu
ω-transaminase can mediate the asymmetric synthesis of chiral amines from aldehydes and ketones , which has important value in the synthesis of pharmaceutical intermediates. A novel ω-transaminase derived from Paracoccus pantotrophus ( Pp TA) was obtained and cloned in E. coli BL21(DE3) for expression. The enzyme has high activity for 2-ketobutyric acid and benzylamine , as well as for aromatic compounds with side chains longer than ethyl aliphatic hydrocarbons . Molecular simulation showed that the S-pocket in the active center is larger than those of other ω-transaminases. Thereafter, a whole-cell catalytic system was designed to prepare l -2-aminobutyric acid by cascading Pp TA and other enzymes. By using several strategies (regulation of RBS intensity, by-product decomposition and cofactor self-sufficiency), whole-cell cascade biocatalysis showed a high ee value (> 99%) and high yield (71%) in one pot reaction . This study therefore proposes an efficient biocatalyst for the synthesis of unnatural amino acids with the participation of ω-transaminase.
研究领域:
生物催化
·
酶工程
·
药物化学
·
分子生物学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2025
·
IF 8.5
Alei Zhang,Runke Wang,Xi Zhou,Quanzhen Liu,Xin Zhang,Feifei Chen,Kequan Chen
In this work, a GH18 chitinase (Chi1) with highly hydrolytic activity was identified from Chitinibacter sp. GC72 and successfully cloned and expressed in Escherichia coli BL21(DE3). The recombinant Chi1 exhibited specific activities of 362.6 U/mg against colloidal chitin and 56.7 U/mg against raw α-chitin. Analysis of hydrolysis pattern showed that Chi1 is a multifunctional chitinase, which mainly exhibited processive exo-acting activity with some endo-acting and N -acetyl glucosaminidase activities. Structural analysis and molecular docking were conducted to explore the potential mechanism underlying the highly and multiple activities. Furthermore, Chi1 was utilized to convert raw α-chitin into reducing sugar affording 48.6% ( w / w ) yield of total sugar with a 1:4 molar ratio of NAG to NAG 2 , while also displaying hydrolysis activity to chitinous biomass with 4.1% sugar yield. This study provides a potent chitinase to hydrolyze chitinous resource with unusual product pattern, showing great potential for further industrial applications.
研究领域:
微生物学
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分子生物学
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生物技术
·
酶学
·
生物信息学
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环境生物技术
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工业生物技术
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结构生物学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）