摘要
      揭示了不同代头孢菌素（CEPs，即萘酸头孢曼多和硫酸头孢吡罗）对废活性污泥发酵过程中挥发性脂肪酸（VFAs）产生和抗生素抗性基因（ARGs）命运的不同影响。CEPs的存在主要对VFAs的总产量表现出负面影响（减少5%-15%），尤其是萘酸头孢曼多，这与以前的理解截然不同。进一步的研究表明，CEPs有助于增溶和水解，但通过影响功能微生物种群（即提西耶菌）和一般微生物代谢活性（即丙酮酸代谢和VFAs生物合成）来抑制酸化过程。此外，在WAS发酵过程中，CEPs（尤其是硫酸头孢吡罗）引起ARGs（即blaTEM、tetX和mexF）的繁殖。CEPs增强细胞膜通透性，促进外排泵的抗生素机制和ARGs的水平转移。此外，CEP改变了与ARGs相关的调节系统（即双组分系统）和微生物种群，导致特定ARGs的增殖。总的来说，不同CEP对VFAs生产和ARGs变化的WAS发酵的不同影响揭示了人为污染物的不同环境行为，并引发了对生态风险的警惕。
Abstract
The distinct influences of cephalosporins (CEPs, i.e., cefamandole nafate and cefpirome sulfate) affiliated to different generations on the volatile fatty acids (VFAs) production and antibiotic resistance genes (ARGs) fates during waste activated sludge (WAS) fermentation were unveiled. The presence of CEPs mainly exhibited negative effects on the total VFAs production (5%–15% reduction), especially the cefamandole nafate, which is quite different to previous understanding. Further investigation revealed that the CEPs contributed to the solubilization and hydrolysis but inhibited the acidification process by affecting the functional microbial populations (i.e., Tissierella) and general microbial metabolic activities (i.e., pyruvate metabolism and VFAs biosynthesis). In addition, CEPs (especially the cefpirome sulfate) caused the propagation of ARGs (i.e., blaTEM, tetX and mexF) during WAS fermentation. CEPs enhanced the cell membrane permeability to promote the antibiotics mechanism of efflux pump and the horizontal transfer of ARGs. Also, the CEPs altered the regulatory systems (i.e., two component system) and microbial populations associated with ARGs, resulting in the proliferation of specific ARGs. Overall, the dissimilarity of different CEPs impacts on the WAS fermentation for VFAs production and ARGs variations enlightened the diverse environmental behaviors of anthropogenic pollutants and evoked the caution of ecological risks.

https://www.sciencedirect.com/science/article/abs/pii/S1001841722006672