<p>Association of CRISPR/Cas System with the Drug Resistance in <em>Klebsiella pneumoniae</em></p>

Abstract

Background: Klebsiella pneumoniae is a common opportunistic pathogen and its production of extended-spectrum β-lactamases (ESBL) and carbapenemases leads to drug resistance. Clustered regularly interspaced short palindromic repeats (CRISPRs) and their associated genes (Cas) are widespread in the genome of many bacteria and are a defense mechanism against foreign invaders such as plasmids and viruses. Purpose: To investigate the prevalence of the CRISPR/Cas system in wild type strains of K. pneumoniae in the hospital and its association with drug resistance. Materials and Methods: A total of 136 strains were collected and characterized their susceptibility to antimicrobial agents. The prevalence of CRISPR/Cas system was detected by PCR and DNA sequencing was analyzed by CRISPRFinder. The statistical analysis of the results was performed by SPSS. Results: We found that 50/136 (37%) isolates produced ESBL and 30/136 (22%) isolates were resistant to carbapenems. These isolates were liable to be multidrug resistant against β-lactams, quinolones, and aminoglycosides. Among the carbapenem-resistant isolates, blaKPC was the main drug resistance-associated gene and different types of ESBL and AmpC genes were present. Resistance to β-lactams, quinolones, aminoglycosides, tetracyclines, and β-lactams/enzyme inhibitor were higher in absence of the CRISPR/Cas system. Eighteen spacers within the CRISPR arrays matched with the genomes of plasmids or phages, some of which carried drug resistance genes. Conclusion: ESBL-producing and carbapenem-resistant K. pneumoniae are more likely to develop multidrug resistance and show an inverse correlation between drug resistance and CRISPR/Cas system. Absence of CRISPR/Cas modules allow for the acquisition of external drug resistance genes.

The Involvement of the csy1 Gene in the Antimicrobial Resistance of Acinetobacter baumannii

“…The study by Aydin et al suggested that the CRISPR-Cas system may interfere with the acquisition of resistant plasmids, thereby maintaining the sensitivity of these strains ( 9 ). Klebsiella pneumoniae strains detected that the spacers in the CRISPR array matched the genome of the plasmid or phage, some containing resistance genes ( 29 ). In Francis bacteria , CRISPR-Cas can enhance the integrity of its envelope, leading to resistance to several membrane stressors, including antibiotics, and increasing antibiotic resistance ( 10 ).…”

A Rapid Antimicrobial Susceptibility Test for Klebsiella pneumoniae Using a Broth Micro-Dilution Combined with MALDI TOF MS

“…The genotype of drug resistance was screened by PCR for carbapenemase genes ( blaKPC, blaNDM, blaIMP, blaVIM, blaSME, blaGES ), ESBL genes ( blaCTX-M, blaTEM, blaSHV ) and AmpC genes ( blaFOX, blaDHA, blaMOX, blaCIT, blaACC, blaEBC ). 26 Then, DNA sequencing was conducted by Sangon (Shanghai, China). The PCR results were validated by nucleotide BLAST searches using GenBank.…”

Prevalence of CRISPR-Cas Systems and Their Possible Association with Antibiotic Resistance in Enterococcus faecalis and Enterococcus faecium Collected from Hospital Wastewater

“…The existence of the CRISPR-Cas system has been found to have a highly substantial negative association with the antibiotic resistance in some bacteria. 13 , 14 However, very few studies have addressed this issue so far, and even in some of them, a positive association has been reported. 9 Hence, this study aimed to evaluate the presence of CRISPR-Cas system genes and their possible association with antibiotic resistance patterns of E. faecalis and E. faecium isolated from HWW samples of several hospitals.…”