Ramos Micaela Santana, Furlan João Pedro Rueda, Gallo Inara Fernanda Lage, Dos Santos Lucas David Rodrigues, de Campos Tatiana Amabile, Savazzi Eduardo Angelino, Stehling Eliana Guedes
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (USP), Ribeirão Preto, Brazil.
Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília (UnB), Brasília, Brazil.
Curr Microbiol. 2020 Oct;77(10):2694-2701. doi: 10.1007/s00284-020-02052-w. Epub 2020 May 30.
Antimicrobial-resistant bacteria (ARB) carrying antimicrobial resistance genes (ARGs) have been increasingly detected in water sources. Pseudomonas sp. are opportunistic pathogens commonly reported in water samples and different antimicrobial resistance mechanisms have been described in Pseudomonas sp., producing multidrug-resistant (MDR) phenotype. Besides, the presence of heavy metal resistance genes (HMRGs) may select ARB, which is worrying. Therefore, this study aimed to characterize the genotypes of Pseudomonas sp. isolated from different water sources. Water samples (i.e., rivers, streams, lakes and sewage treatment plants) were collected from different cities in Brazil. The bacterial identification was performed by sequencing the 16S rDNA and the resistance profile to antimicrobials and heavy metals were determined by minimum inhibitory concentration (MIC). Several ARGs, HMRGs, and plasmids were researched by PCR and the amplicons were sequenced for confirmation. A total of 23 Pseudomonas sp. isolates were obtained and identified as Pseudomonas saponiphila, Pseudomonas hunanensis, Pseudomonas aeruginosa, and Pseudomonas asiatica. These isolates presented high MICs to antimicrobials and heavy metals, being the great majority (n = 21; 91%) classified as MDR. Different clinically important ARGs were detected, such as bla, qnrS, qepA, tetB, aac(3')-IIa, and ant(2″)-Ia. The czcA gene was the only HMRG detected and no plasmids were found. To the best of our knowledge, this is the first report of the world of P. saponiphila carrying ARGs (i.e., bla, qnrS, aac(3')-IIa, tetB) and QepA-producing P. hunanensis and the first time of P. saponiphila, P. asiatica, and P. hunanensis in Brazil.
在水源中越来越多地检测到携带抗菌抗性基因（ARGs）的耐抗菌细菌（ARB）。假单胞菌属是水样中常见的机会致病菌，并且已经描述了假单胞菌属中不同的抗菌抗性机制，产生多重耐药（MDR）表型。此外，重金属抗性基因（HMRGs）的存在可能会选择ARB，这令人担忧。因此，本研究旨在对从不同水源分离的假单胞菌属的基因型进行表征。从巴西不同城市采集水样（即河流、溪流、湖泊和污水处理厂）。通过对16S rDNA进行测序进行细菌鉴定，并通过最低抑菌浓度（MIC）确定对抗菌药物和重金属的抗性谱。通过PCR研究了几种ARGs、HMRGs和质粒，并对扩增子进行测序以进行确认。共获得23株假单胞菌属分离株，鉴定为嗜皂假单胞菌、湖南假单胞菌、铜绿假单胞菌和亚洲假单胞菌。这些分离株对抗菌药物和重金属呈现出高MIC值，绝大多数（n = 21；91%）被归类为MDR。检测到不同的临床重要ARGs，如bla、qnrS、qepA、tetB、aac(3')-IIa和ant(2″)-Ia。czcA基因是检测到的唯一HMRG，未发现质粒。据我们所知，这是世界上关于携带ARGs（即bla、qnrS、aac(3')-IIa、tetB） 的嗜皂假单胞菌以及产QepA的湖南假单胞菌的首次报道，也是巴西首次报道嗜皂假单胞菌、亚洲假单胞菌和湖南假单胞菌。
