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Anthraquinones, a widely distributed class of aromatic natural products, are produced by a type II polyketide synthase system in the Gram-negative bacterium . Heterologous expression of the anthraquinone biosynthetic gene cluster in identified AntI as an unusual lyase, catalysing terminal polyketide shortening prior to formation of the third aromatic ring. Functional and analysis of AntI using X-ray crystallography, structure-based mutagenesis, and molecular simulations revealed that AntI converts a defined octaketide to the tricyclic anthraquinone ring retro-Claisen and Dieckmann reactions. Thus, AntI catalyses a so far unobserved multistep reaction in this PKS system.
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http://dx.doi.org/10.1039/c9sc00749k | DOI Listing |
APMIS
August 2025
Department of Otolaryngology, The First Affiliated Hospital of Dali University, Dali, Yunnan, China.
This study is intended to expound the effect of clarithromycin combined with oxymetazoline hydrochloride (OZH) spray in acute exacerbations of chronic rhinosinusitis (AECRS). Patients with AECRS were retrospectively collected and divided into a control group and an observation group. The control group received clarithromycin, and the observation group received OZH spray in addition to clarithromycin.
View Article and Find Full Text PDFPestic Biochem Physiol
August 2025
State Key Laboratory of Agricultural and Forestry Biosecurity, College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China. Electronic address:
Azadirachtin, a natural sesquiterpenoid compound, exhibits broad-spectrum insecticidal activity, yet its mechanism of action remains incompletely understood. This study aimed to elucidate its toxicological mechanisms by developing an azadirachtin-resistant Drosophila strain through continuous laboratory selection. After five years of directional screening, we successfully established the Aza-Sel strain with a resistance ratio of 86.
View Article and Find Full Text PDFMedicine (Baltimore)
June 2025
Department of Paediatrics, Fengcheng Hospital of Fengxian District, Shanghai, China.
Influenza A virus pneumonia in children is a serious respiratory infection disease. In view of the limitations of single treatment at present, this study aims to explore the clinical effect of glucocorticoid (GC) combined with azithromycin (AZM) on it. the data of 75 children with swine flu pneumonia were analyzed retrospectively, and they were divided into GC group (GCG), AZM group (AZMG), and GC + AZM group (combined group, CG) according to the treatment scheme, with 25 cases in each group.
View Article and Find Full Text PDFFungal Biol Biotechnol
June 2025
Institut für Biotechnologie und Wirkstoff-Forschung gGmbH, Mainz, Hanns-Dieter-Hüsch Weg 17, D-55128, Mainz, Germany.
Paecilomyces marquandii IBWF 003-21 produces vibrant purple pigmented conidia, the color of which can be attributed to the naphthacenedione natural product saintopin (1). The target compound was previously reported to exhibit potent topoisomerase-inhibitory activity, yet has not been extensively studied nor has the biosynthesis been elucidated. In an effort to elucidate the biosynthesis of 1, we mined the genome of Paecilomyces marquandii for non-reducing polyketide synthases (nrPKS), introduced them into the heterologous host Aspergillus oryzae OP12 and identified a prime candidate for the biosynthesis of 1 we termed stpA.
View Article and Find Full Text PDFMicroorganisms
March 2025
College of Agriculture, Shihezi University, Shihezi 832003, China.
Endosymbiotic bacteria play a significant role in the co-evolution of insects and plants. However, whether they induce or inhibit host plant defense responses remains unclear. In this study, non-targeted metabolomic sequencing was performed on cotton leaves fed with -infected and uninfected spider mites using parthenogenetic backcrossing and antibiotic treatment methods.
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