المؤلفون: Yin, Hang, Cui, Shitong, Cao, Yufei, Ge, Jun^{Aff2, Aff3, IDs12010023046678_cor4}, Lou, Wenyong^{Aff1, IDs12010023046678_cor5}

المصدر: Applied Biochemistry and Biotechnology. 196(6):2977-2989

المؤلفون: Tekucheva, D. N.^{Aff1, IDS0026261723603913_cor1}, Karpov, M. V., Fokina, V. V., Timakova, T. A., Shutov, A. A., Donova, M. V.

المصدر: Microbiology. 93(2):134-138

المؤلفون: Duan, Xiaoyan, Pi, Qian, Tang, Lei^{Aff1, Aff2, IDs00449024029688_cor3}

المصدر: Bioprocess and Biosystems Engineering. 47(3):355-366

المؤلفون: Zetian Qiu, Xiaohui Liu, Jie Yu, Yushuo Zhao, Guang-Rong Zhao, Shengying Li, Kun Liu, Lei Du, Li Ma

المصدر: Synthetic and Systems Biotechnology, Vol 9, Iss 2, Pp 187-195 (2024)

مصطلحات موضوعية: Benzyl acids, Phenylpropanoid acids, Alcohol dehydrogenases, Aldehyde dehydrogenases, Whole-cell catalysis, Biotechnology, TP248.13-248.65, Biology (General), QH301-705.5

الوصف: Benzyl and phenylpropanoid acids are widely used in organic synthesis of fine chemicals, such as pharmaceuticals and condiments. However, biocatalysis of these acids has received less attention than chemical synthesis. One of the main challenges for biological production is the limited availability of alcohol dehydrogenases and aldehyde dehydrogenases. Environmental microorganisms are potential sources of these enzymes. In this study, 129 alcohol dehydrogenases and 42 aldehyde dehydrogenases from Corynebacterium glutamicum, Pseudomonas aeruginosa, and Bacillus subtilis were identified and explored with various benzyl and phenylpropanoid alcohol and aldehyde substrates, among which four alcohol dehydrogenases and four aldehyde dehydrogenases with broad substrate specificity and high catalytic activity were obtained. Moreover, a cascade whole-cell catalytic system including ADH-90, ALDH-40, and the NAD(P)H oxidase LreNox was established, which showed high efficiency in converting cinnamyl alcohol and p-methylbenzyl alcohol into the respective carboxylic acids. Remarkably, this biocatalytic system can be easily scaled up to gram-level production, facilitating preparation purposes.

وصف الملف: electronic resource

Relation: http://www.sciencedirect.com/science/article/pii/S2405805X24000085; https://doaj.org/toc/2405-805X

URL الوصول: https://doaj.org/article/ffaaa1e3ffe3499da709c632565bf05b

المؤلفون: Xin-Xin Liu, Yao Wang, Jian-Hui Zhang, Yun-Feng Lu, Zi-Xing Dong, Chao Yue, Xian-Qing Huang, Si-Pu Zhang, Dan-Dan Li, Lun-Guang Yao, Cun-Duo Tang

المصدر: Biotechnology for Biofuels and Bioproducts, Vol 17, Iss 1, Pp 1-15 (2024)

مصطلحات موضوعية: 2,5-dimethylpyrazine, Metabolic engineering, Microbial cell factories, Aminoacetone oxidase, Threonine transporter, Whole-cell catalysis, Biotechnology, TP248.13-248.65, Fuel, TP315-360

الوصف: Abstract 2,5-Dimethylpyrazine (2,5-DMP) is important pharmaceutical raw material and food flavoring agent. Recently, engineering microbes to produce 2,5-DMP has become an attractive alternative to chemical synthesis approach. In this study, metabolic engineering strategies were used to optimize the modified Escherichia coli BL21 (DE3) strain for efficient synthesis of 2,5-DMP using L-threonine dehydrogenase (EcTDH) from Escherichia coli BL21, NADH oxidase (EhNOX) from Enterococcus hirae, aminoacetone oxidase (ScAAO) from Streptococcus cristatus and L-threonine transporter protein (EcSstT) from Escherichia coli BL21, respectively. We further optimized the reaction conditions for synthesizing 2,5-DMP. In optimized conditions, the modified strain can convert L-threonine to obtain 2,5-DMP with a yield of 2897.30 mg/L. Therefore, the strategies used in this study contribute to the development of high-level cell factories for 2,5-DMP. Graphical Abstract

وصف الملف: electronic resource

Relation: https://doaj.org/toc/2731-3654

URL الوصول: https://doaj.org/article/267bb24cc90941ecab3450356ab41a9a

المؤلفون: Gamache, Mira T., Charaf, Rima, Kurth, Larissa, Filmon, Dawit T., Senger, Moritz, Plumere, Nicolas, Hammarström, Leif, 1964, Berggren, Gustav

المصدر: ACS Catalysis. 13(14):9476-9486

مصطلحات موضوعية: hydrogenase, whole-cell catalysis, semi-artificialphotosynthesis, hydrogen, transient absorption, redox mediator, sacrificial electron donor

الوصف: Both photo- and biocatalysis are well-established andintensivelystudied. The combination of these two approaches is also an emergingresearch field, commonly referred to as semi-artificial photosynthesis.Semi-artificial photosynthesis aims at combining highly efficientsynthetic light harvesters with the self-healing and potent catalyticproperties of biocatalysis. In this study, a semi-artificial photocatalyticsystem featuring Escherichia coli bacteria,which heterologously express the [FeFe] hydrogenase enzyme HydA1 fromgreen algae, is employed as a hydrogen gas production catalyst. Toprobe the influence of photochemistry on overall system performance,the E. coli whole-cell catalyst iscombined with two different photosensitizers and redox mediators.The addition of a redox mediator greatly improves the rates and longevityof the photocatalytic system, as reflected in increases of both theturn-over number (0.777 vs 10.9 & mu;mol H-2 mL(-1) OD600 (-1)) and the turn-over frequency(175 vs 334 & mu;mol H-2 mL(-1) h(-1) OD600 (-1)). The redoxmediator is found to both protect from photobleaching and enable electrontransport to the hydrogenase from an extracellular photosensitizer.However, E. coli cells are stronglyaffected by the photocatalytic system, leading to a decrease in cellintegrity and cell viability, possibly due to toxic decompositionproducts formed during the photocatalytic process. We furthermoreemployed steady-state and transient absorption spectroscopy to investigatesolution potentials and the kinetics of electron transfer processesbetween the sacrificial electron donor, photosensitizer, redox mediator,and the [FeFe] hydrogenase as the final electron acceptor. These resultsallowed us to rationalize the different activities observed in photocatalyticassays and offer a better understanding of the factors that influencethe photocatalytic performance of E. coli-based whole-cell systems.

وصف الملف: electronic

URL الوصول: https://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-510973
https://doi.org/10.1021/acscatal.3c01347
https://uu.diva-portal.org/smash/get/diva2:1794714/FULLTEXT01.pdf

المؤلفون: Gu, Jinhui, Li, Qisi, Cao, Mengting, Zhang, Xiaojia, Ding, Xinpei, Chen, Haiyan, Wang, Nan, Zhang, Zhijun^{Aff1, Aff2, Aff3, IDs41664023002604_cor8}

المصدر: Journal of Analysis and Testing. 7(3):237-244

المؤلفون: Duan, Zhiwen^{Aff1, Aff2}, Wang, Yaowu^{Aff1, Aff2}, Ouyang, Bin^{Aff1, Aff2}, Wang, Pu^{Aff1, Aff2, IDs0044902302897y_cor4}

المصدر: Bioprocess and Biosystems Engineering. 46(9):1293-1302

المؤلفون: Chixiang Sun, Baodong Hu, Yanchun Li, Zhimeng Wu, Jingwen Zhou, Jianghua Li, Jian Chen, Guocheng Du, Xinrui Zhao

المصدر: Synthetic and Systems Biotechnology, Vol 8, Iss 4, Pp 741-748 (2023)

مصطلحات موضوعية: OleP, Deoxycholic acid, Hydroxylation, Redox partners, Whole-cell catalysis, Biotechnology, TP248.13-248.65, Biology (General), QH301-705.5

الوصف: Deoxycholic acid (DCA) has been authorized by the Federal Drug Agency for cosmetic reduction of redundant submental fat. The hydroxylated product (6β-OH DCA) was developed to improve the solubility and pharmaceutic properties of DCA for further applications. Herein, a combinatorial catalytic strategy was applied to construct a powerful Cytochrome P450 biocatalyst (CYP107D1, OleP) to convert DCA to 6β-OH DCA. Firstly, the weak expression of OleP was significantly improved using pRSFDuet-1 plasmid in the E. coli C41 (DE3) strain. Next, the supply of heme was enhanced by the moderate overexpression of crucial genes in the heme biosynthetic pathway. In addition, a new biosensor was developed to select the appropriate redox partner. Furthermore, a cost-effective whole-cell catalytic system was constructed, resulting in the highest reported conversion rate of 6β-OH DCA (from 4.8% to 99.1%). The combinatorial catalytic strategies applied in this study provide an efficient method to synthesize high-value-added hydroxylated compounds by P450s.

وصف الملف: electronic resource

Relation: http://www.sciencedirect.com/science/article/pii/S2405805X23000959; https://doaj.org/toc/2405-805X

URL الوصول: https://doaj.org/article/06667365f0a5446589a985bc5a0229de

المؤلفون: Gao, Siyuan, Ma, Ding, Wang, Yongtao, Zhang, Alei, Wang, Xin^{Aff1, IDs12896023007946_cor5}, Chen, Kequan

المصدر: BMC Biotechnology. 23(1)