Abstract：
The substantial use of antibiotics contributes to the spread and evolution of antibiotic resistance, posing potential risks to food production systems, including mushroom production. In this study, the potential risk of antibiotics to Stropharia rugosoannulata, the third most productive straw-rotting mushroom in China, was assessed, and the underlying mechanisms were investigated. Tetracycline exposure at environmentally relevant concentrations (<500 μg/L) did not influence the growth of S. rugosoannulata mycelia, while high concentrations of tetracycline (>500 mg/L) slightly inhibited its growth. Biodegradation was identified as the main antibiotic removal mechanism in S. rugosoannulata, with a degradation rate reaching 98.31 % at 200 mg/L tetracycline. High antibiotic removal efficiency was observed with secreted proteins of S. rugosoannulata, showing removal efficiency in the order of tetracyclines > sulfadiazines > quinolones. Antibiotic degradation products lost the ability to inhibit the growth of Escherichia coli, and tetracycline degradation products could not confer a growth advantage to antibiotic-resistant strains. Two laccases, SrLAC1 and SrLAC9, responsible for antibiotic degradation were identified based on proteomic analysis. Eleven antibiotics from tetracyclines, sulfonamides, and quinolones families could be transformed by these two laccases with degradation rates of 95.54-99.95 %, 54.43-100 %, and 5.68-57.12 %, respectively. The biosafety of the antibiotic degradation products was evaluated using the Toxicity Estimation Software Tool (TEST), revealing a decreased toxicity or no toxic effect. None of the S. rugosoannulata fruiting bodies from seven provinces in China contained detectable antibiotic-resistance genes (ARGs). This study demonstrated that S. rugosoannulata can degrade antibiotics into non-toxic and non-bactericidal products that do not accelerate the spread of antibiotic resistance, ensuring the safety of S. rugosoannulata production.
摘要：
抗生素的大量使用有助于抗生素耐药性的传播和演变，对食品生产系统构成潜在风险，包括蘑菇生产。在这项研究中,抗生素对rugosoonulata的潜在风险，中国第三大产秸秆腐烂蘑菇，被评估,并对其潜在机制进行了研究。暴露于环境相关浓度（<500μg/L）的四环素不会影响轮状链球菌菌丝体的生长，而高浓度四环素(>500mg/L)对其生长有轻微抑制作用。生物降解被确定为rugosoannulata中主要的抗生素去除机制，200mg/L四环素的降解率达到98.31%。观察到rugosoannulata分泌蛋白的高抗生素去除效率，显示去除效率顺序为四环素类>磺胺嘧啶类>喹诺酮类。抗生素降解产物失去抑制大肠杆菌生长的能力，四环素降解产物不能赋予抗生素抗性菌株生长优势。两个漆酶,基于蛋白质组分析鉴定负责抗生素降解的SrLAC1和SrLAC9。十一种四环素类抗生素,磺胺类药物,这两种漆酶可以转化喹诺酮家族，降解率为95.54-99.95%，54.43-100%,5.68-57.12%，分别。使用毒性评估软件工具（TEST）评估抗生素降解产物的生物安全性，显示毒性降低或无毒性作用。来自中国七个省的rugosoannulata子实体均未检测到抗生素抗性基因（ARGs）。这项研究表明，rugososoannulata可以将抗生素降解为无毒和非杀菌的产品，不会加速抗生素耐药性的传播，确保紫杉生产的安全。
