Rational Design of Copper(II)-Uracil Nanoprocessed Coordination Polymers to Improve Their Cytotoxic Activity in Biological Media

Unraveling Multicopper [Cu3] and [Cu6] Clusters with Rare μ3-Sulfato and Linear μ2-Oxido-Bridges as Potent Antibiofilm Agents against Multidrug-Resistant Staphylococcus aureus

In this research article, two multicopper [Cu3] and [Cu6] clusters, [Cu3(cpdp)(μ3-SO4)(Cl)(H2O)2]·3H2O (1) and [Cu6(cpdp)2(μ2-O)(Cl)2(H2O)4]·2Cl (2) (H3cpdp = N,N'-bis[2-carboxybenzomethyl]-N,N'-bis[2-pyridylmethyl]-1,3-diaminopropan-2-ol), have been explored as potent antibacterial and antibiofilm agents. Their molecular structures have been determined by a single-crystal X-ray diffraction study, and the compositions have been established by thermal and elemental analyses, including electrospray ionization mass spectrometry. Structural analysis shows that the metallic core of 1 is composed of a trinuclear [Cu3] assembly encapsulating a μ3-SO42- group, whereas the structure of 2 represents a hexanuclear [Cu6] assembly in which two trinuclear [Cu3] motifs are exclusively bridged by a linear μ2-O2- group. The most striking feature of the structure of 2 is the occurrence of an unusual linear oxido-bridge, with the Cu3-O6-Cu3' bridging angle being 180.00°. Whereas 1 can be viewed as an example of a copper(II)-based compound displaying a rare μ3:η1:η1:η1 bridging mode of the SO42- group, 2 is the first example of any copper(II)-based compound showing an unsupported linear Cu-O-Cu oxido-bridge. Employing variable-temperature SQUID magnetometry, the magnetic susceptibility data were measured and analyzed exemplarily for 1 in the temperature range of 2-300 K, revealing the occurrence of antiferromagnetic interactions among the paramagnetic copper centers. Both 1 and 2 exhibited potent antibacterial and antibiofilm activities against methicillin-resistant Staphylococcus aureus (MRSA BAA1717) and the clinically isolated culture of methicillin-resistant S. aureus (MRSA CI1). The mechanism of antibacterial and antibiofilm activities of these multicopper clusters was investigated by analyzing and determining the intracellular reactive oxygen species (ROS) generation, lipid peroxidation, microscopic observation of cell membrane disruption, membrane potential, and leakage of cellular components. Additionally, 1 and 2 showed a synergistic effect with commercially available antibiotics such as vancomycin with enhanced antibacterial activity. However, 1 possesses higher antibacterial, antibiofilm, and antivirulence actions, making it a potent therapeutic agent against both MRSA BAA1717 and MRSA CI1 strains.

Structural and Theoretical Study of Copper(II)-5-fluoro Uracil Acetate Coordination Compounds: Single-Crystal to Single-Crystal Transformation as Possible Humidity Sensor

This paper describes the synthesis and characterization of seven different copper(II) coordination compounds, as well as the formation of a protonated ligand involving all compounds from the same reaction. Their synthesis required hydrothermal conditions, causing the partial in situ transformation of 5-fluoro uracil-1-acetic acid (5-FUA) into an oxalate ion (ox), as well as the protonation of the 4,4'-bipyridine (bipy) ligand through a catalytic process resulting from the presence of Cu(II) within the reaction. These initial conditions allowed obtaining the new coordination compounds [Cu₂(5-FUA)₂(ox)(bipy)]_n·2n H₂O (CP2), [Cu(5-FUA)₂(H₂O)(bipy)]_n·2n H₂O (CP3), as well as the ionic pair [(H₂bipy)⁺² 2NO₃^-] (1). The mother liquor evolved rapidly at room temperature and atmospheric pressure, due to the change in concentration of the initial reagents and the presence of the new chemical species generated in the reaction process, yielding CPs [Cu(5-FUA)₂(bipy)]_n·3.5n H₂O, [Cu₃(ox)₃(bipy)₄]_n and [Cu(ox)(bipy)]_n. The molecular compound [Cu(5-FUA)₂(H₂O)₄]·4H₂O (more thermodynamically stable) ended up in the mother liquor after filtration at longer reaction times at 25 °C and 1 atm., cohabiting in the medium with the other crystalline solids in different proportions. In addition, the evaporation of H₂O caused the single-crystal to single-crystal transformation (SCSC) of [Cu(5-FUA)₂(H₂O)(bipy)]_n·2n H₂O (CP3) into [Cu(5-FUA)₂(bipy)]_n·2n H₂O (CP4). A theoretical study was performed to analyze the thermodynamic stability of the phases. The observed SCSC transformation also involved a perceptible color change, highlighting this compound as a possible water sensor.

Identification of a prognostic model using cuproptosis-related genes in uveal melanoma

The most common intraocular malignancy in adults remains uveal melanoma (UVM), and those with metastatic disease have a poor outlook. Proliferation, angiogenesis, and metastasis of tumor cells can be triggered by cuproptosis, affecting the survival of cancer patients. Nonetheless, cuproptosis-related genes (CRGs) have not been identified in UVM. In this study, we analyzed 10 CRGs in 80 patients with UVM in the Cancer Genome Atlas (TCGA) database regarding the alterations of the genes including copy number variation and methylation. We further constructed a prognostic gene model using these CRGs and built the risk score formula. Univariate and multivariate Cox regression was applied to validate the risk score as an independent prognostic factor. The prognostic model was validated using 63 UVM samples from the GSE22138 cohort, an independent validation data set. Based on the risk scores for 80 patients with UVM from TCGA, we categorized the patients into high- and low-risk groups. Differentially expressed genes (DEGs) between groups were enriched in allograft rejection, hypoxia, glycolysis, TNFα signaling via NF-κB, and interferon-γ responses via Gene set enrichment analysis (GSEA). CD8 T cells and exhausted T cells were notably enriched in the high-risk group. In conclusion, the alteration of CRGs is related to patients with UVM, and the constructed CRG-related model may be helpful to predict the prognosis of such patients.