Escherichia coli K12 strains producing L-phenylalanine were converted to L-tyrosine-producing strains using a novel genetic method for gene replacement. We deleted a region of the E. coli K12 chromosome including the pheA gene encoding chorismate mutase/prephenate dehydratase, its leader peptide (pheL), and its promoter using a new polymerase chain reaction-based method that does not leave a chromosomal scar. For high level expression of tyrA, encoding chorismate mutase/prephenate dehydrogenase, its native promoter was replaced with the strong trc promoter. The linked DeltapheLA and Ptrc-tyrA::Kan(R) genetic modifications were moved into L-phenylalanine producing strains by generalized transduction to convert L-phenylalanine-producing strains to L-tyrosine-producing strains. Moreover, introduction of a plasmid carrying genes responsible for sucrose degradation into these strains enabled L-tyrosine-production from sucrose.
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Front Mol Biosci
January 2025
Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland.
Introduction: Chronic inflammation caused by infections has a significant negative impact on the reproductive system and impairs fertility. The corpus luteum (CL) plays a central role not only in regulating the ovary cycle, but also in implantation of the embryo and maintenance of early pregnancy through the secretion of progesterone. Understanding the intricate interplay between inflammatory processes and reproductive organ's function is crucial for the development of effective therapeutic strategies to alleviate reproductive disorders and improve fertility.
View Article and Find Full Text PDFScientificWorldJournal
January 2025
Department of Biology, College of Science, Bahir Dar University, P. O. Box 79, Bahir Dar, Ethiopia.
The present study was aimed to verify the medicinal value of and traditionally used to treat human and animal ailments in Ethiopia. Fresh leaves of these species were collected, dried under shade, and ground into fine powder. The extraction was carried out by the maceration method using methanol as a solvent.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Department of Chemistry, School of Sciences & Engineering, The American University in Cairo AUC Avenue, P.O. Box 74 New Cairo 11835 Egypt +202 2615 2559.
Biofilms formed by several bacterial strains still pose a significant challenge to healthcare due to their resistance to conventional treatment approaches, including antibiotics. This study explores the potential of loading natural extracts with antimicrobial activities into β-cyclodextrin (βCD) nanoparticles, which are FDA-approved and have superior biocompatibility owing to their cyclic sugar structures, for biofilm eradication. An inclusion complex of βCD carrying essential oils (BOS) was prepared and characterized with regard to its physicochemical properties, antimicrobial efficacy, and antibiofilm activities.
View Article and Find Full Text PDFNanoscale Adv
January 2025
Materials Science and Engineering Graduate Program, Faculty of Science, Mahidol University Bangkok 10400 Thailand
Triclosan (TCS) is used as an antibacterial agent in various products. One of the major issues associated with TCS is its limited solubility in aqueous media, which can reduce its effectiveness against bacteria. In this study, we enhanced the aqueous solubility and antibacterial activity of TCS by using a re-dispersible emulsion powder stabilized with gold nanoparticles (GNPs).
View Article and Find Full Text PDFRSC Adv
January 2025
Department of Medicinal Chemistry, Institute of Medical Sciences, Banaras Hindu University Varanasi UP-221005 India
The antibacterial efficacy of some newly developed bis- and C3-carboxylic moieties of fluoroquinolone-linked triazole conjugates was studied. Twenty compounds from two different series of triazoles were synthesized using click chemistry and evaluated for their antibacterial activity against a Gram-positive strain, (ATCC29212), and its clinical isolate and a Gram-negative bacterial strain, (ATCC25922), and its clinical isolate. Among the compounds, 7, 9a, 9d, 9i, 10(a-d), and 10i showed excellent activity with MIC values of up to 6.
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