Association Between Antibiotic Resistance and Integron Class2 Among Commonsal Escherichia coli Genotypic Groups
Authors: M. khadhim Manal , A. Kazaal Meraim 
Published: January 2024

Antibiotic therapies can not affect only on the pathogenic bacteria, but also commensal microorganisms in the humans gut, which might serve as a reservoir of antimicrobial resistance genes. fecal Escherichia coli (E. coli) is often considered as a good indicator for selection pressure imposed by antimicrobial use. The goal of this study was to determine genotyping groups of commonsal E. coli and  investigate the frequency of integrons class 2 and antibiotic resistance among them. So detect the association of integron class2 with antibiotic resistance (single and multiple drug resistance) that may be transport horizontally in bacterial populations. In this study 301isolates of commonsal  E. coli were isolated from stools obtained from healthy individuals with age from 1to 80 years. All isolates were tested for their susceptibility against 16 antimicrobial agents and subjected to conventional polymerase chain reactions (PCR) for detection integrons and multiplex PCR for genotyping analysis. Present results showed that group B2 represent the majority of the collected isolates

(63%) followed by group A (23%) and D (14%) but no strains were found to belong to group B1.  Also results revealed that 10% of isolates have integron class 2 that mainly related to genotypic group B2. High resistance observed for most antibiotics especially ampicilln, amoxcillin, lincomycin, cephalexin while resistance to amikacin and gentamicin was less common. Antibiotic resistance mainly appeared in integron positive isolates. In conclusion, high prevalence of antibiotic resistance especially among integron class 2 positive isolates that indicated role of gut flora as reservoir and source of antibiotic resistance.

Antibiotic therapies can not affect only on the pathogenic bacteria, but also commensal microorganisms in the humans gut, which might serve as a reservoir of antimicrobial resistance genes. fecal Escherichia coli (E. coli) is often considered as a good indicator for selection pressure imposed by antimicrobial use. The goal of this study was to determine genotyping groups of commonsal E. coli and  investigate the frequency of integrons class 2 and antibiotic resistance among them. So detect the association of integron class2 with antibiotic resistance (single and multiple drug resistance) that may be transport horizontally in bacterial populations. In this study 301isolates of commonsal  E. coli were isolated from stools obtained from healthy individuals with age from 1to 80 years. All isolates were tested for their susceptibility against 16 antimicrobial agents and subjected to conventional polymerase chain reactions (PCR) for detection integrons and multiplex PCR for genotyping analysis. Present results showed that group B2 represent the majority of the collected isolates

(63%) followed by group A (23%) and D (14%) but no strains were found to belong to group B1.  Also results revealed that 10% of isolates have integron class 2 that mainly related to genotypic group B2. High resistance observed for most antibiotics especially ampicilln, amoxcillin, lincomycin, cephalexin while resistance to amikacin and gentamicin was less common. Antibiotic resistance mainly appeared in integron positive isolates. In conclusion, high prevalence of antibiotic resistance especially among integron class 2 positive isolates that indicated role of gut flora as reservoir and source of antibiotic resistance.