Type III polyketide synthases (PKSs) are comparatively small homodimeric enzymes affording natural products with diverse structures and functions. While type III PKS biosynthetic pathways have been studied thoroughly in plants, their counterparts from bacteria and fungi are to date scarcely characterized. This gap is exemplified by myxobacteria from which no type III PKS-derived small molecule has previously been isolated. In this study, we conducted a genomic survey of myxobacterial type III PKSs and report the identification of uncommon alkylpyrones as the products of type III PKS biosynthesis from the myxobacterial model strain Myxococcus xanthus DK1622 through a self-resistance-guided screening approach focusing on genes encoding pentapetide repeat proteins, proficient to confer resistance to topoisomerase inhibitors. Using promoter-induced gene expression in the native host as well as heterologous expression of biosynthetic type III PKS genes, sufficient amounts of material could be obtained for structural elucidation and bioactivity testing, revealing potent topoisomerase activity in vitro.
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http://dx.doi.org/10.1007/s10295-018-2105-6 | DOI Listing |
Rev Esp Cir Ortop Traumatol
January 2025
Knee Surgery Unit, iMove Traumatology, Barcelona, Spain; Knee Surgery Unit, Orthopaedic Surgery Department, Hospital Sant Joan de Déu de Manresa - Fundació Althaia, Universitat de Vic, Manresa, Spain.
Introduction: The CPAK classification aims to categorize knee phenotypes. The original study was based on Australian and Belgian population, but significant variation in CPAK distribution exists between different geographic areas. The primary objective is to evaluate knee phenotypes of osteoarthritic Spanish population based on the CPAK system.
View Article and Find Full Text PDFLancet Neurol
February 2025
Department of Neurology, International University of Health and Welfare, Narita, Japan.
Background: Evidence from preclinical studies suggests that IL-6 signalling has the potential to modulate immunopathogenic mechanisms upstream of autoantibody effector mechanisms in patients with generalised myasthenia gravis. We aimed to assess the safety and efficacy of satralizumab, a humanised monoclonal antibody targeting the IL-6 receptor, in patients with generalised myasthenia gravis.
Methods: LUMINESCE was a randomised, double-blind, placebo-controlled, multicentre, phase 3 study at 105 sites, including hospitals and clinics, globally.
J Hazard Mater
January 2025
Advanced Mass Spectrometry Center, Research Core Facility, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610213, China. Electronic address:
Arsenic contamination of water sources, whether from natural or industrial origins, represents a significant risk to human health. However, its impact on waterborne pathogens remains understudied. This research explores the effects of arsenic exposure on the opportunistic pathogen Pseudomonas aeruginosa, a bacterium found in diverse environments.
View Article and Find Full Text PDFAnal Chem
January 2025
School of Life Sciences, Key Laboratory of Space Bioscience & Biotechnology, Northwestern Polytechnical University, Xi'an 710072, China.
Lymphoma is a malignant cancer characterized by a rapidly increasing incidence, complex etiology, and lack of obvious early symptoms. Efficient theranostics of lymphoma is of great significance in improving patient outcomes, empowering informed decision-making, and driving medical innovation. Herein, we developed a multifunctional nanoplatform for precise optical imaging and therapy of lymphoma based on a new photosensitizer (1-oxo-1-benzoo[de]anthracene-2,3-dicarbonitrile-triphenylamine (OBADC-TPA)).
View Article and Find Full Text PDFFront Biosci (Landmark Ed)
January 2025
Department of Neurology, Jinshan Hospital, Fudan University, 201508 Shanghai, China.
Background: Neuronal cholesterol deficiency may contribute to the synaptopathy observed in Alzheimer's disease (AD). However, the underlying mechanisms remain poorly understood. Intact synaptic vesicle (SV) mobility is crucial for normal synaptic function, whereas disrupted SV mobility can trigger the synaptopathy associated with AD.
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