German Federal Institute for Risk Assessment, Berlin, Germany.
German Federal Institute for Risk Assessment, Berlin, Germany
Appl Environ Microbiol. 2019 Oct 1;85(20). doi: 10.1128/AEM.01253-19. Print 2019 Oct 15.
Contamination of food during processing is recognized as a main transmission route of To prevent microbial contamination, biocides are widely applied as disinfectants in food processing plants. However, there are concerns about the development of antimicrobial resistance in foodborne pathogens due to widespread biocide usage. In our study, 93 isolates from German food production facilities were (i) tested for biocide and antibiotic susceptibility using broth microdilution assays, (ii) analyzed for links between reduced biocide susceptibility and antibiotic resistance, and (iii) characterized by whole-genome sequencing, including the detection of genes coding for biocide tolerance, antibiotic resistance, and other virulence factors. Fifteen isolates were tolerant to benzalkonium chloride (BAC), and genes conferring BAC tolerance were found in 13 of them. Antibiotic resistance was not associated with biocide tolerance. BAC-tolerant isolates were assigned to 6 multilocus sequence type (MLST) clonal complexes, and most of them harbored internalin A pseudogenes with premature stop codons or deletions ( = 9). Our study demonstrated a high genetic diversity among the investigated isolates including genotypes that are frequently involved in human infections. Although adaptation studies to biocides have raised concerns about increasing cross-resistance to antibiotics, our results do not provide evidence for this phenomenon in field isolates. Foodborne pathogens such as can persist in food production environments for a long time, causing perennial outbreaks. Hence, bacterial pathogens are able to survive cleaning and disinfection procedures. Accordingly, they may be repeatedly exposed to sublethal concentrations of disinfectants, which might result in bacterial adaptation to these biocides. Furthermore, antibiotic coresistance and cross-resistance are known to evolve under biocide selection pressure Hence, antimicrobial tolerance seems to play a crucial role in the resilience and persistence of foodborne pathogens in the food chain and might reduce therapeutic options in infectious diseases.
在食品加工过程中，食品受到污染被认为是主要的传播途径。为了防止微生物污染，杀菌剂被广泛用作食品加工厂的消毒剂。然而，由于杀菌剂的广泛使用，人们担心食源性致病菌会产生抗药性。在我们的研究中，从德国食品生产设施中分离出了 93 株（i）采用肉汤微量稀释法检测杀菌剂和抗生素敏感性，（ii）分析杀菌剂敏感性降低与抗生素耐药性之间的关系，（iii）通过全基因组测序进行表征，包括检测编码杀菌剂耐受性、抗生素耐药性和其他毒力因子的基因。15 株分离物对苯扎氯铵（BAC）具有耐受性，其中 13 株分离物中发现了赋予 BAC 耐受性的基因。抗生素耐药性与杀菌剂耐受性无关。BAC 耐受分离物被分配到 6 个多位点序列型（MLST）克隆复合体，其中大多数携带内部素 A 假基因，具有过早的终止密码子或缺失（ = 9）。我们的研究表明，在所研究的分离物中存在高度的遗传多样性，包括与人类感染频繁相关的基因型。尽管针对杀菌剂的适应性研究引起了人们对增加对抗生素交叉耐药性的担忧，但我们的研究结果并未在田间分离物中提供这一现象的证据。食源性致病菌，如 ，可以在食品生产环境中长时间存活，导致常年爆发。因此，细菌病原体能够在清洗和消毒程序中存活下来。因此，它们可能会反复暴露于亚致死浓度的消毒剂下，这可能导致细菌对这些杀菌剂产生适应性。此外，抗生素核心耐药性和交叉耐药性已知在杀菌剂选择压力下进化 因此，抗菌剂耐受性似乎在食源性致病菌在食物链中的弹性和持久性中起着至关重要的作用，并可能减少传染病治疗的选择。
