The interaction between extracellular polymeric substances (EPS) in municipal sludge and antibiotics in wastewater is critical in wastewater treatment, resource recovery, and sludge management. Therefore, it is increasingly urgent to investigate the distribution coefficient (Log K) of sulfonamide antibiotics (SAs) in EPS, particularly in sludge-derived dissolved organic carbon (DOC) and aqueous phase systems. Herein, through balance experiments, the concentrations of SAs were determined using alkaline extraction EPS (AEPS) and alginate-like extracellular polymer (ALE) systems, and the Log K values were determined. The results showed that the Log K of AEPS was higher than that of ALE, which exhibited a negative K value, indicating an inhibitory effect on dissolution. For the three SAs studied, the Log K values were in the following order: sulfamethoxazole > sulfapyridine > sulfadiazine. This order can be attributed to the differing physicochemical properties, such as polarity, of the SAs. Three-dimensional excitation-emission matrix fluorescence spectra and fitting results indicated a lack of aromatic proteins dominated by tryptophan and humus-like substances in ALE. Meanwhile, the hydrophobic interaction of aromatic proteins dominated by tryptophan was the main driving force in the binding process between AEPS and SAs.
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http://dx.doi.org/10.1016/j.envres.2024.119576 | DOI Listing |
Nat Commun
December 2024
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.
The general control non-repressible 5 (GCN5)-related N-acetyltransferase (GNAT) SbzI, in the biosynthesis of the sulfonamide antibiotic altemicidin, catalyzes the transfer of the 2-sulfamoylacetyl (2-SA) moiety onto 6-azatetrahydroindane dinucleotide. While most GNAT superfamily utilize acyl-coenzyme A (acyl-CoA) as substrates, SbzI recognizes a carrier-protein (CP)-tethered 2-SA substrate. Moreover, SbzI is the only naturally occurring enzyme that catalyzes the direct incorporation of sulfonamide, a valuable pharmacophore in medicinal chemistry.
View Article and Find Full Text PDFWater Res
December 2024
CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China. Electronic address:
Heterotrophic nitrification, similar to autotrophic nitrification, involves key enzymes and reactive nitrogen intermediates during ammonia oxidation, which may influence antibiotic transformation. However, the interference between antibiotic transformation products from ammonia oxidation and secondary metabolites in heterotrophic nitrifiers makes antibiotic transformation pathways more complicated. In this work, we observe that the heterotrophic nitrifier Alcaligenes ammonioxydans HO-1 can effectively convert sulfonamide antibiotics.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Riverbank filtration (RBF) is an effective pretreatment technology for drinking water, removing organic micropollutants (OMPs) mainly through biodegradation. Despite documented improvements in OMP removal with extended adaptation time, the mechanisms remain poorly understood. This study assessed the removal of 128 OMPs over 82 d in a simulated RBF system, identified those with improved removal, and analyzed their properties.
View Article and Find Full Text PDFVet Sci
December 2024
Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, TN 37996, USA.
This study evaluated the concentrations of tetracycline, erythromycin, and sulfonamide in beef, eggs, and honey products sold at grocery stores and whether standard cooking to 160 °F (71 °C) reduced the concentrations of antimicrobials spiked into the evaluated food products. In June 2021, the concentrations of selected antimicrobials in 65 samples (8 beef, 48 eggs, 9 honey samples) purchased from grocery stores within Knoxville, Tennessee, were measured using enzyme-linked immunosorbent assays. The Kruskal-Wallis test was used to assess the differences in the median tetracycline concentrations across food types, while the Mann-Whitney test was used to compare the erythromycin residue concentrations between beef and honey.
View Article and Find Full Text PDFInt J Hyg Environ Health
December 2024
Department of Chemistry, Institute of Exact and Biological Sciences, Federal University of Ouro Preto (UFOP), Ouro Preto, 35450-000, Minas Gerais, Brazil.
Trimethoprim (TMP) and sulfamethoxazole (SMX) are bacteriostatic agents, which are co-administered to patients during infection treatment due to their synergetic effects. Once consumed, TMP and SMX end up in wastewater and are directed to municipal wastewater treatment plants (WWTPs) which fail to remove these contaminants from municipal wastewater. The discharge of WWTP effluents containing antibiotics in the environment is a major concern for public health as it contributes to the spread of antimicrobial resistance.
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