Biocatalytic transformations in reversed micelles formed by anionic surfactant Aerosol OT in octane have been studied at high pressures by an example of alpha-chymotrypsin-catalyzed hydrolysis of N-carbobenzoxy-L-tyrosine p-nitrophenyl ester and N-succinyl-L-phenylalanine p-nitroanilide. For the first time it has been found that the enzyme retains high activity in these water-in-oil microemulsions up to a pressure of 2 kbar. The value of the activation volume (delta V*) for the enzyme reactions shows a dependence on the water content in the system. When the size of the micellar aqueous inner cavity (as evaluated at 1 atm) approaches the molecular size of alpha-chymotrypsin, delta V* becomes significantly different from the value in aqueous solution and in the micelles with a larger size. Possibilities of regulating the enzyme activity by pressure in systems with a low content of water are discussed.
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Biochemistry
January 2025
Department of Chemistry, Texas A&M University, College Station, Texas 77842, United States.
The exterior surface of the human pathogen is coated with a capsular polysaccharide (CPS) that consists of a repeating sequence of 2-5 different sugars that can be modified with various molecular decorations. In the HS:2 serotype from strain NCTC 11168, the repeating unit within the CPS is composed of d-ribose, -acetyl-d-galactosamine, and a d-glucuronic acid that is further amidated with either serinol or ethanolamine. The d-glucuronic acid moiety is also decorated with d-glycero-l-gluco-heptose.
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January 2025
Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.
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January 2025
Faculty of Psychology, Universitas Ahmad Dahlan, Yogyakarta, Indonesia.
Indonesia is still the second-highest tuberculosis burden country in the world. The antituberculosis adverse drug reaction and adherence may influence the success of treatment. The objective of this study is to define the model for predicting the adherence in tuberculosis patients, based on the increased level of liver enzymes.
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Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China.
Lignin degradation by biocatalysts is a key strategy to develop a plant-based sustainable carbon economy and thus alleviate global climate change. This process involves synergy between ligninases and auxiliary enzymes. However, auxiliary enzymes within secretomes, which are composed of thousands of enzymes, remain enigmatic, although several ligninolytic enzymes have been well characterized.
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January 2025
Institut Pasteur, Department of Structural Biology and Chemistry, 28 Rue du Dr. Roux, 75015, Paris, FRANCE.
Access to synthetic oligonucleotides is crucial for applications in diagnostics, therapeutics, synthetic biology, and nanotechnology. Traditional solid phase synthesis is limited by sequence length and complexities, low yields, high costs and poor sustainability. Similarly, polymerase-based approaches such as in vitro transcription and primer extension reactions do not permit any control on the positioning of modifications and display poor substrate tolerance.
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