Vázquez Xenia, Fernández Javier, Hernáez Silvia, Rodicio Rosaura, Rodicio Maria Rosario
Departamento de Biología Funcional, Área de Microbiología, Universidad de Oviedo (UO), 33006 Oviedo, Spain.
Grupo de Microbiología Traslacional, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain.
Microorganisms. 2022 Mar 7;10(3):579. doi: 10.3390/microorganisms10030579.
Non-typhoid serovars of are one of the main causes of bacterial food-borne infections worldwide. For the treatment of severe cases of salmonellosis in adults, fluoroquinolones are amongst the drugs of choice. They are categorized by the World Health Organization (WHO) as "critically important with highest priority in human medicine". In the present study, two clinical serovar Corvallis isolates (HUA 5/18 and HUA 6/18) from a Spanish hospital, selected on the basis of fluoroquinolone resistance, were characterized. The MICs of ciprofloxacin, determined by E-test, were 0.5 and 0.75 µg/mL for HUA 5/18 and HUA 6/18, respectively, and both were also resistant to pefloxacin but susceptible to nalidixic acid. Whole genome sequencing (WGS) of the isolates was performed with Illumina platform, and different bioinformatics tools were used for sequence analysis. The two isolates belonged to ST1541, and had the Thr57Ser substitution in the ParC protein which is also found in ciprofloxacin susceptible isolates. However, they harbored identical ColE plasmids of 10 kb carrying the gene. In these plasmids, the gene was flanked by defective versions of IS-like and IS-like insertion sequences. HUA 5/18 and HUA 6/18 were also phenotypically resistant to streptomycin, sulfonamides and tetracycline, with the responsible genes: , , and (A) genes, being located on a IncQ1 plasmid. ColE plasmids with the gene are widely spread among multiple serovars of from different samples and countries. These mobilizable plasmids are playing an important role in the worldwide spread of . Thus, their detection in hospitals is a cause of concern which deserves further attention.
非伤寒血清型沙门氏菌是全球细菌性食源性感染的主要原因之一。对于成人严重沙门氏菌病的治疗，氟喹诺酮类药物是首选药物之一。它们被世界卫生组织（WHO）归类为“人类医学中具有最高优先级的极其重要的药物”。在本研究中，对从一家西班牙医院选取的两株临床沙门氏菌血清型科瓦利斯分离株（HUA 5/18和HUA 6/18）进行了特征分析，这两株分离株是基于对氟喹诺酮类药物的耐药性而挑选出来的。通过E-test测定，环丙沙星对HUA 5/18和HUA 6/18的最低抑菌浓度（MIC）分别为0.5和0.75μg/mL，并且二者对培氟沙星也耐药，但对萘啶酸敏感。使用Illumina平台对分离株进行全基因组测序（WGS），并使用不同的生物信息学工具进行序列分析。这两株分离株属于ST1541，并且在ParC蛋白中具有Thr57Ser替换，这种替换在对环丙沙星敏感的分离株中也有发现。然而，它们携带相同的10 kb ColE质粒，该质粒携带基因。在这些质粒中，基因两侧是类IS和类IS插入序列有缺陷的版本。HUA 5/18和HUA ⑥18对链霉素、磺胺类药物和四环素也表现出表型耐药，其相关基因：、、和（A）基因位于IncQ1质粒上。携带基因的ColE质粒在来自不同样本和国家的多种沙门氏菌血清型中广泛传播。这些可移动质粒在沙门氏菌的全球传播中发挥着重要作用。因此，在医院中检测到它们是一个值得关注的问题，值得进一步关注。
