Infection and Drug Resistance (Mar 2022)
Prevalence of CRISPR-Cas Systems and Their Possible Association with Antibiotic Resistance in Enterococcus faecalis and Enterococcus faecium Collected from Hospital Wastewater
Abstract
Athraa Harjan Mohsen Alduhaidhawi,1 Sundus Nsaif AlHuchaimi,2 Thikra Abdullah Al- Mayah,2 Mushtak TS Al-Ouqaili,3 Samar Sami Alkafaas,4 Saravanan Muthupandian,5,6 Morteza Saki7 1Department of Biology, Faculty of Science, University of Kufa, Najaf, Iraq; 2Department of Parasitology, Faculty of Medicine, University of Kufa, Najaf, Iraq; 3Department of Microbiology, College of Medicine, University of Anbar, Ramadi, Al-Anbar Governorate, Iraq; 4Department of Chemistry, Division of Biochemistry, Faculty of Science, Tanta University, Tanta, Egypt; 5Department of Microbiology and Immunology, Division of Biomedical Sciences, School of Medicine, College of Health Sciences, Mekelle University, Mekelle, 1871, Ethiopia; 6Department of Pharmacology, AMR and Nanomedicine Laboratory, Center for Transdisciplinary Research, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, 60007, India; 7Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IranCorrespondence: Saravanan Muthupandian, Department of Microbiology and Immunology, Division of Biomedical Sciences, School of Medicine, College of Health Sciences, Mekelle University, Mekelle, 1871, Ethiopia, Tel +919443077097, Email [email protected] Morteza Saki, Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran, Tel +989364221187, Email [email protected]: This study aimed to evaluate the presence of CRISPR-Cas system genes and their possible association with antibiotic resistance patterns of Enterococcus faecalis and Enterococcus faecium species isolated from hospital wastewater (HWW) samples of several hospitals.Methods: HWW samples (200 mL) were collected from wastewater discharged from different hospitals from October 2020 to March 2021. The isolation and identification of enterococci species were performed by standard bacteriology tests and polymerase chain reaction (PCR). Antibiotic resistance was determined using the disc diffusion. The presence of various CRISPR-Cas systems was investigated by PCR. The association of the occurrence of CRISPR-Cas systems with antibiotic resistance was analyzed with appropriate statistical tests.Results: In total, 85 different enterococci species were isolated and identified using phenotypic methods. The results of PCR confirmed the prevalence of 50 (58.8%) E. faecalis and 35 (41.2%) E. faecium, respectively. In total, 54 (63.5%) of 85 isolates showed the presence of CRISPR-Cas loci. The incidence of CRISPR-Cas was more common in E. faecalis. CRISPR1, CRISPR2, and CRISPR3 were present in 35 (41.2%), 47 (55.3%), and 30 (35.3%) enterococci isolates, respectively. The CRISPR-Cas positive isolates showed significant lower resistance rates against vancomycin, ampicillin, chloramphenicol, erythromycin, rifampin, teicoplanin, tetracycline, imipenem, tigecycline, and trimethoprim-sulfamethoxazole in comparison with CRISPR-Cas negative isolates. The results showed that the presence of CRISPR-Cas genes was lower in multidrug-resistant (MDR) isolates (53.1%, n = 26/49) compared to the non-MDR enterococci isolates (77.8%, n = 28/36) (P = 0.023).Conclusion: This study revealed the higher prevalence of E. faecalis than E. faecium in HWWs. Also, the lack of CRISPR-Cas genes was associated with more antibiotic resistance rates and multidrug resistance in E. faecalis and E. faecium isolates with HWW origin.Keywords: antibiotic resistance, CRISPR-Cas, Enterococcus faecalis, Enterococcus faecium, hospital wastewater, HWW
