As complications associated with antibiotic resistance have intensified, copper (Cu) is attracting attention as an antimicrobial agent. Recent studies have shown that copper surfaces decrease microbial burden, and host macrophages use Cu to increase bacterial killing. Not surprisingly, microbes have evolved mechanisms to tightly control intracellular Cu pools and protect against Cu toxicity. Here, we identified two genes ( and ) encoded within the arginine-catabolic mobile element (ACME) that we hypothesized function in Cu homeostasis. Supporting this hypothesis, mutational inactivation of or increased copper sensitivity. We found that are co-transcribed and that their transcription is increased during copper stress and in a strain in which , encoding a Cu-responsive transcriptional repressor, was mutated. Moreover, displayed genetic synergy with suggesting that CopB functions in Cu export. We further observed that CopL functions independently of CopB or CopA in Cu toxicity protection and that CopL from the clone USA300 is a membrane-bound and surface-exposed lipoprotein that binds up to four Cu ions. Solution NMR structures of the homologous CopL, together with phylogenetic analysis and chemical-shift perturbation experiments, identified conserved residues potentially involved in Cu coordination. The solution NMR structure also revealed a novel Cu-binding architecture. Of note, a CopL variant with defective Cu binding did not protect against Cu toxicity Taken together, these findings indicate that the ACME-encoded CopB and CopL proteins are additional factors utilized by the highly successful USA300 clone to suppress copper toxicity.
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http://dx.doi.org/10.1074/jbc.RA118.004723 | DOI Listing |
Environ Sci Pollut Res Int
January 2025
Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas, Av. Instituto Politécnico Nacional S/N, Playa Palo de Santa Rita, C.P. 23096, La Paz, Baja California Sur, Mexico.
The present review provides the first analysis and synthesis of the available scientific information on the effects of anthropogenic contaminants on cephalopod embryos, paralarvae, and juveniles. We evaluated 46 articles published between 1970 and 2023 that focused on trace elements (69%), pharmaceutical compounds (11%), persistent organic compounds (11%), and plastics (9%). To date, the greatest scientific effort has originated from Europe and Asia (France [57%], China [9%], Italy [7%], and Spain [4%]), with few reports available from the rest of the world.
View Article and Find Full Text PDFSci Rep
January 2025
College of Jilin Emergency Management, Changchun Institute of Technology, Changchun, 130012, China.
Globally, heavy metal (HM) soil pollution is becoming an increasingly serious concern. Heavy metals in soils pose significant environmental and health risks due to their persistence, toxicity, and potential for bioaccumulation. These metals often originate from anthropogenic activities such as industrial emissions, agricultural practices, and improper waste disposal.
View Article and Find Full Text PDFMol Biol Res Commun
January 2025
Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan.
J Dent
December 2024
Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan; Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Electronic address:
Objectives: To evaluate the multifunctionality of silver-copper co-loaded mesoporous bioactive glass (MBG), with the goal of developing an advanced pulp-capping material.
Methods: The synthesis of materials was conducted using the sol-gel method, following the approach described in previous studies but with some modifications. The composition included 80 mol% SiO₂, 15 mol% CaO, and 5 mol% P₂O₅, with additional components of 5 mol% silver, 5 mol% copper, or 1 mol% silver combined with 4 mol% copper, designated as Ag5/80S, Cu5/80S, or Ag1Cu4/80S, respectively.
Int J Biol Macromol
December 2024
Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China. Electronic address:
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