Antimicrobials resistance patterns and the presence of stx1, stx2 and eae in Escherichia coli

Abstract

The objectives of this study were to investigate whether antimicrobial resistance (AMR) or the presence of resistance genes was associated with the occurrence of the virulence genes, stx1, stx2 andeae. Three virulence genes and 11 AMR phenotypes were examined using polymerase chain reaction (PCR) and antimicrobial susceptibility tests. From 800 samples collected in this study, 561 samples were isolatesE. coli strains , being: 90 (16.0%) carriers ofstx1, 97 (17.3%) of stx2 and 45 (8.0%) ofeae genes singly. Thirty seven (6.6%) isolates were carriers of stx1 and stx2, 110 (19.6%) were carriers of stx1 and eae and 67 (11.9%) were carriers of stx2 and eae. The most common virulence gene detected was stx1followed bystx2. The findings showed no relationship between presence of virulence factors and antimicrobial resistance. Also was not found relationship between serogroup and virulence factors.

Molecular characterization of Escherichia coli recovered from traditional milk products in Kashan, Iran

“…Assumpção et al . [ 5 ] demonstrated that the STEC isolates that carried stx1 only showed highest antimicrobial resistance to streptomycin (85.6%), followed by kanamycin (72.2%), and nalidixic acid (70.0%). Furthermore, STEC strains carrying stx2 only showed highest antimicrobial resistance to streptomycin (73.2%), followed by kanamycin and nalidixic acid (70.1%).…”

“…In recent years, Shiga toxigenic E. coli (STEC) strains as emerging groups of foodborne pathogens are responsible for most foodborne illnesses [ 5 ]. The pathogenicity of these strains almost related to the ability of the microorganism to produce the one or two cytotoxins called Shiga toxins ( stx1 and stx2 ), and the presence of the intimin ( eae ) gene, which is responsible for intimate attachment of the organism to the intestinal epithelium [ 5 , 6 ].…”

“…Previous studies have demonstrated that antibiotic resistance levels in STEC are increasing. In addition, there is a great probability of association between the presence of virulence factors and antibiotic resistance [ 5 , 7 ]. When, at the same time, the presence of virulence factors with antibiotic resistance in bacteria happens, the antibiotics use may potentially increase the selection of bacteria carrying virulence genes, accelerating the expansion of virulence genes within bacteria [ 8 ].…”

“…Assumpção et al . [ 5 ] reported from 561 E. coli isolates, 90 (16.0%) were carriers of stx1 , 97 (17.3%) of stx2 , and 45 (8.0%) of eae genes singly. 37 (6.6%) isolates were carriers of stx1 and stx2 , 110 (19.6%) were carriers of stx1 and eae , and 67 (11.9%) were carriers of stx2 and eae .…”

Molecular characterization and antimicrobial resistance of STEC strains isolated from healthy cattle in 2011 and 2013 in Spain

“…Table 4. Total number of resistances and antimicrobial resistance (AMR) patterns (resistotypes) found for each of the isolates tested 1 000 000 000 1 26 1 000 100 000 2 27 1 001 010 000 3 28 1 001 100 000 3 29 1 001 100 000 3 30 1 001 110 000 4 31 1 001 110 000 4 32 1 001 110 000 4 33 1 001 110 000 4 34 1 001 110 000 4 35 1 001 110 010 5 36 1 001 111 000 5 37 1 001 111 000 5 38 1 001 111 100 6 39 1 001 111 100 6 40 1 001 111 100 6 41 1 001 111 100 6 42 1 001 111 100 6 43 1 001 111 100 6 44 1 010 100 000 3 45 1 011 101 * AMR for each resistotype is shown in the following order: CIP-SMX-GENT-AMP-TET-STR-TMP-CLOR-FF-C-KAN-NAL. FOT, TAZ and COL were not used in the concatenation for obtaining each resistotype as all isolates were susceptible to these antimicrobials.…”