The fosfomycin (1) resistance proteins FosA and FosX in pathogenic microorganisms are related to a catalytically promiscuous progenitor encoded in a phn operon in Mesorhizobium loti. The mlr3345 gene product (FosX(Ml)) from M. loti has a very low epoxide hydrolase activity and even lower glutathione transferase activity toward 1 and does not confer resistance to the antibiotic. In vitro homologous recombination of the mlr3345 and pa1129 genes (a fosA gene from Pseudomonas aeruginosa that does confer robust resistance to 1) produces recombinant proteins that confer resistance to 1 and indicate that the FosA resistance proteins are functionally and genetically related to mlr3345.
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http://dx.doi.org/10.1021/bi900078q | DOI Listing |
Nat Commun
January 2025
University of St Andrews, School of Biology, North Haugh, Biomolecular Sciences Building, St Andrews, UK.
Cyclic dipeptides are produced by organisms across all domains of life, with many exhibiting anticancer and antimicrobial properties. Oxidations are often key to their biological activities, particularly C-C bond oxidation catalysed by tailoring enzymes including cyclodipeptide oxidases. These flavin-dependent enzymes are underexplored due to their intricate three-dimensional arrangement involving multiple copies of two distinct small subunits, and mechanistic details underlying substrate selection and catalysis are lacking.
View Article and Find Full Text PDFSheng Wu Gong Cheng Xue Bao
January 2025
College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China.
As important biocatalysts, nitrilases can efficiently convert nitrile groups into acids and ammonia in a mild and eco-friendly manner, being widely used in the synthesis of important pharmaceutical intermediates. Early studies reported that nitrilases only had the hydrolysis activity of catalyzing the formation of corresponding carboxylic acid products from nitriles, showing catalytic specificity. However, recent studies have shown that some nitrilases exhibit the hydration activity for catalyzing the formation of amides from nitriles, showing catalytic promiscuity.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
The structural groups of 2-oxindole and tricyclic 3a-hydroxy-hexahydropyrrolo-[2,3-]indole (HO-HPI) are important pharmacophores. Chemical synthesis of complex alkaloids containing a 2-oxindole or HO-HPI moiety, especially the latter one, has been a long-standing challenge. Herein, we characterized the P450 enzyme AfnD, and its homologue proteins, HmtT, ClpD, KtzM, and LtzR, as cyclopeptide 2-oxindole and HO-HPI monooxygenases (cpOPMOs) that could introduce a 2-oxindole or HO-HPI moiety into the tryptophan-containing cyclopeptides in a pH-dependent manner.
View Article and Find Full Text PDFNature
January 2025
Manchester Institute of Biotechnology, The University of Manchester, Manchester, UK.
Nucleophilic aromatic substitutions (SAr) are amongst the most widely used processes in the pharmaceutical and agrochemical industries, allowing convergent assembly of complex molecules through C-C and C-X (X = O, N, S) bond formation. SAr reactions are typically carried out using forcing conditions, involving polar aprotic solvents, stoichiometric bases and elevated temperatures, which do not allow for control over reaction selectivity. Despite the importance of SAr chemistry, there are only a handful of selective catalytic methods reported that rely on small organic hydrogen-bonding or phase-transfer catalysts.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
National Resource Center for Chinese Meteria Medica, China Academy of Chinese Medical Sciences, Beijing 100700, China; State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs, Beijing 100700, China.
Glycosylation is an effective means to alter the structure and properties of plant compounds, influencing the pharmacological activity of natural products (NPs) to obtain highly active NPs. In nature, glucosides are the most widely distributed, while other glycosides such as xylosides are less common and present in lower quantities. This is due to the scarcity of xylosyltransferases with substrate promiscuity in nature, and the modification of their catalytic function is also quite challenging.
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