RT Journal Article
T1 Sulfamethoxazole is Metabolized and Mineralized at Extremely Low Concentrations
A1 López Gordillo, Ana Paulina
A1 Trueba Santiso, Alba María
A1 Lema Rodicio, Juan Manuel
A1 Schäffer, Andreas
A1 Smith, Kilian E. C.
K1 Antibiotic
K1 Biotransformation
K1 Biodegradation
K1 Organic micropollutants
K1 Microbacterium sp BR1
K1 14C−CO2
K1 Threshold
AB The presence of organic micropollutants in water and sediments motivates investigation of their biotransformation at environmentally low concentrations, usually in the range of μg L–1. Many are biotransformed by cometabolic mechanisms; however, there is scarce information concerning their direct metabolization in this concentration range. Threshold concentrations for microbial assimilation have been reported in both pure and mixed cultures from different origins. The literature suggests a range value for bacterial growth of 1–100 μg L–1 for isolated aerobic heterotrophs in the presence of a single substrate. We aimed to investigate, as a model case, the threshold level for sulfamethoxazole (SMX) metabolization in pure cultures of Microbacterium strain BR1. Previous research with this strain has covered the milligram L–1 range. In this study, acclimated cultures were exposed to concentrations from 0.1 to 25 μg L–1 of 14C-labeled SMX, and the 14C–CO2 produced was trapped and quantified over 24 h. Interestingly, SMX removal was rapid, with 98% removed within 2 h. In contrast, mineralization was slower, with a consistent percentage of 60.0 ± 0.7% found at all concentrations. Mineralization rates increased with rising concentrations. Therefore, this study shows that bacteria are capable of the direct metabolization of organic micropollutants at extremely low concentrations (sub μg L–1)
PB ACS
SN 0013-936X
YR 2024
FD 2024-05-18
LK http://hdl.handle.net/10347/34849
UL http://hdl.handle.net/10347/34849
LA eng
NO Environ. Sci. Technol. 2024, 58, 22, 9723–9730
NO This work was funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 812880 (MSCA-ITN-2018: EJD Nowelties). A.T.-S. acknowledges a Juan de la Cierva-Formación postdoctoral grant (FJC2019-041664-I). A.T.-S. and J.M.L. belong to the Galician Competitive Research Group (GRC)_ ED431C-2021/37
DS Minerva
RD 24 abr 2026