{Reference Type}: Journal Article {Title}: Reducing residual chlortetracycline in wastewater using a whole-cell biocatalyst. {Author}: Liu M;Wang C;Qi XE;Du S;Ni H; {Journal}: Ecotoxicol Environ Saf {Volume}: 282 {Issue}: 0 {Year}: 2024 Sep 1 {Factor}: 7.129 {DOI}: 10.1016/j.ecoenv.2024.116717 {Abstract}: Antibiotic contamination has become an increasingly important environmental problem as a potentially hazardous emergent and recalcitrant pollutant that poses threats to human health. In this study, manganese peroxidase displayed on the outer membrane of Escherichia coli as a whole-cell biocatalyst (E. coli MnP) was expected to degrade antibiotics. The manganese peroxidase activity of the whole-cell biocatalyst was 13.88 ± 0.25 U/L. The typical tetracycline antibiotic chlortetracycline was used to analyze the degradation process. Chlortetracycline at 50 mg/L was effectively transformed via the whole-cell biocatalyst within 18 h. After six repeated batch reactions, the whole-cell biocatalyst retained 87.2 % of the initial activity and retained over 87.46 % of the initial enzyme activity after storage at 25°C for 40 days. Chlortetracycline could be effectively removed from pharmaceutical and livestock wastewater by the whole-cell biocatalyst. Thus, efficient whole-cell biocatalysts are effective alternatives for degrading recalcitrant antibiotics and have potential applications in treating environmental antibiotic contamination.