摘要

在兽医和人类医学中，细菌中抗生素抗性的发展受到显着挑战。在这项研究中，我们分析了携带部落Proteeae作为喹诺酮抗性决定因子来源的宠物龟的潜在风险，包括质粒介导的喹诺酮抗性（PMQR）基因和喹诺酮抗性决定区（QRDR）中的靶基因改变。检测了54株Proteeae分离株对环丙沙星，氧氟沙星，左氧氟沙星和萘啶酸的抗菌药物敏感性。使用常规PCR测定和测序鉴定PMQR基因和QRDR改变。四种分离株对本研究中测试的所有喹诺酮类药物均有抗性。 9株分离株对萘啶酸显示出耐药性，并表现出中等抗性或对其他测试喹诺酮类药物的敏感性。所有对一种或多种测试喹诺酮类抗生素的分离株都含有gyrB突变，有些还具有gyrA和parC突变。在54个中，12个Proteeae分离株在gyrB中显示出新的E466D，N440T，Q411S和F417L突变。在PMQR基因中，41个（76％）分离株携带qnrD基因，患病率最高，而aac（6'）Ib-cr，qnrS，qnrA和qnrB基因检测到28个（52％），9个（17.0％） ），7（13.0％）和1（1.9％）研究分离株。所选突变体的QRDR分析显示，增加喹诺酮选择压力导致gyrA突变体占优势。所有结果表明，健康的宠物龟可以作为喹诺酮类抗性蛋白酶的潜在储存器，它可能会对宠物主人造成公共健康风险。

Development of antibiotic resistance in bacteria has challenged significantly in both veterinary and human medicine. In this study, we analyzed the potential risk of pet turtles harboring tribe Proteeae as a source of quinolone-resistant determinants, including plasmid-mediated quinolone resistance (PMQR) genes and target gene alterations in the quinolone resistance-determining region (QRDR). Antimicrobial susceptibility of 54 Proteeae isolates against ciprofloxacin, ofloxacin, levofloxacin, and nalidixic acid was examined. The PMQR genes and QRDR alterations were identified using conventional PCR assays and sequencing. Four isolates were resistant to all quinolones tested in this study. Nine isolates showed resistance to nalidixic acid and showed either intermediate resistance or susceptibility to other tested quinolones. All isolates resistant to one or more tested quinolones harbored mutations in gyrB and some also had gyrA and parC mutations. Of 54, 12 Proteeae isolates displayed the novel E466D, N440T, Q411S, and F417L mutations in gyrB. Among the PMQR genes, 41 (76%) isolates harbored the qnrD gene with the highest prevalence, whereas aac(6')Ib-cr, qnrS, qnrA, and qnrB genes were detected in 28 (52%), 9 (17.0%), 7 (13.0%), and 1 (1.9%) study isolates, respectively. The QRDR analysis of selected mutants revealed that increasing quinolone selective pressure led to a predominance of gyrA mutants. All results indicate that a healthy pet turtle can play as a potential reservoir for quinolone-resistant Proteeae, which it might cause public health risk on pet owners.

https://www.ncbi.nlm.nih.gov/pubmed/30427748