The same aminoglycoside 2"-adenylyltransferase was isolated from four gram-negative species which were among a random group of gentamicin-resistant isolates from the same hospital. The enzyme was partially purified from a crude extract which also contained a second modifying enzyme identified as APH(3')-I. The substrate range of the new aminoglycoside 2"-adenylyltransferase included the newer aminoglycosides sisomicin and amikacin, but showed much-reduced activity against gentamicins C2 and Cla. The pH optimum was 7.8 to 8.0 for every substrate, and the molecular weight of the enzyme molecule was estimated at approximately 29,000. Genetic experiments clearly established that both enzymes were expressed by a conjugative plasmid.
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http://dx.doi.org/10.1128/AAC.20.1.75 | DOI Listing |
Sci Rep
January 2025
Mechanical and Industrial Engineering Department, Universitas Gadjah Mada, Yogyakarta, Indonesia.
Research on flexible strain sensors has grown rapidly and is widely applied in the fields of soft robotics, body motion detection, wearable sensors, health monitoring, and sports. In this study, MXene was successfully synthesized in powder form and combined with multi-walled carbon nanotube (MWCNT) to develop MWCNT@MXene conductive network-based flexible strain sensors with silicone rubber (SR) substrate. Combining MWCNTs with MXene as a conductive material has been shown to significantly improve the sensor performance, due to MXene's high conductivity properties that strengthen the MWCNT conductive pathway, increase sensitivity, and improve sensor stability.
View Article and Find Full Text PDFSci Rep
January 2025
School of Advanced Technologies, Iran University of Science and Technology, Tehran, 1684613114, Iran.
This study presents a very thin wideband linear polarization converter in transmission mode with near-unity conversion efficiency. The suggested converter consists of a periodic array on a single-layer substrate, two metallic layers and six vias. Metallic vias connect the upper and lower layers of the construction.
View Article and Find Full Text PDFNat Commun
January 2025
School of Pharmacy, Zunyi Medical University, Zunyi, 563000, China.
Although biocatalysis offers complementary or alternative approaches to traditional synthetic methods, the limited range of available enzymatic reactions currently poses challenges in synthesizing a diverse array of desired compounds. Consequently, there is a significant demand for developing novel biocatalytic processes to enable reactions that were previously unattainable. Herein, we report the discovery and subsequent protein engineering of a unique halohydrin dehalogenase to develop a biocatalytic platform for enantioselective formation and ring-opening of oxetanes.
View Article and Find Full Text PDFJ Biotechnol
January 2025
CNRS, University of Bordeaux, CRPP, UMR5031, 115 Avenue Schweitzer, F-33600 Pessac, France.
Enhancing the local substrate concentration is a crucial strategy in nature for facilitating the proximity of two enzymes. The substrate of the first enzyme is transformed into a by-product that travels to the active site of the second enzyme without external diffusion, then transformed into a product and eventually expelled from the complex. In an effort to optimize the antimicrobial properties of myeloperoxidase from Rhodopirellula baltica (RbMPO), we created a library of fused chimeras between a glucose oxidase (GOx) and RbMPO so that HO could be continuously perfused in the vicinity RbMPO, enabling the production of HOCl or HOSCN, well-known antimicrobial agents.
View Article and Find Full Text PDFPlant Dis
January 2025
Wenshan University, Wenshan Sanqi Institute of Science and Technology, Wenshan, Yunnan, China;
The roots of Salvia yunnanensis, an herbaceous perennial widely distributed in Southwest China, is often used as a substitute for S. miltiorrhiza, a highly valued plant in traditional Chinese medicine (Wu et al. 2014).
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