CORRELATION AMONG CRISPR-CAS SYSTEMS AND ANTIBIOTIC RESISTANCE BLACTX-M GENE IN UPEC

Abstract

The treatment of patients with infections caused by organisms producing beta-lactamases especially   is often associated with many problems due to the spread of antibiotic resistance. blaCTX-M, of plasmid origin, as an ESBL producing gene, plays an important role in the development of antibiotic resistance. The CRISPR/Cas system, as a new immune system in bacteria, causes adaptive resistance to foreign genetic elements. This study investigated the distribution of CRISPR-associated cas1,2,3 genes and their association with the presence of  blaCTX-M gene in Escherichia coli isolated from urinary tract infections. Uropathogenic E. coli samples (UPEC) collected from several Mazandaran and Tehran’s hospitals. Detection of antibiotic resistance and beta-lactamase phenotypic was performed using the disk diffusion method. After DNA extraction from isolates, PCR was performed for cas1,2,3 and ctx-M genes with specific primer. Results showed that out of 106 UPEC isolates, 28.3% isolates were detected as ESBL- producing. The findings of this study showed 35.9% of isolates carried blaCTX-M gene and 61.76% of isolates have simultaneous cas1 and cas3 gene. Overall, there was no significant  relationship between the presence of cas1,2,3 genes and beta-lactamase phenotype activity. Also, no correlation was in presence of cas genes and antibiotic resistance. The results showed no significant relation was between the presence of CRISPR-associated cas and ctx-M genes. So the CRISPR system is not a suitable solution for the deletion of betalactamase resistance antibiotic.