Molecular Investigation of Some Beta-lactamase Genes by PCR and DNA Sequencing Techniques in clinical Escherichia coli

Abstract

In this study, out of 50 isolates of some nosocomial infections from some Baghdad hospitals, only 13 (26%) were identified as Escherichia coli. Depending on selective media, morphological and biochemical tests the species was then confirmed by molecular methods. Later on antimicrobial resistance test was performed by the Kirby-Bauer method. The molecular characterization of blaTEM and blaCTX-M genes in different clinical isolates of E. coli was done through polymerase chain reaction (PCR) by utilizing special primers. These genes were positive to only 4 (30.7%) isolates. The sequence of nucleotides of positive genes was carried out for four isolates. The results showed that there was no variance in the nucleotide sequence between Iraqi isolates compared with the global isolates, and that they were 100% identical to many genera of Enterobacteriaceae. Finally, due to the indiscriminate use of antibiotics, these genes in human strains were likely the source of widespread drug resistance.

Detection of Resistance Genes (Blandm and Blavim) of Escherichia Coli in the Aquatic Environment

“…Where there may be resistance genes other than those that have been studied that can confer resistance to the studied bacterial isolates. Bacteria may also develop mechanisms to reduce drug penetration into their cells, therefore E.coli has many mechanisms of resistance to βlactam antibiotics like loss of porin and efflux pumps [15][16][17]. The findings were agreed with other previous research which illustrated high resistance of E. coli to penicillin and most cephalosporins antibiotics [18] and agreements with other studies in low resistance to some antibiotics [19].…”

Dissemination of Class A Cephalosporinases and Class D Carbapenemases in Escherichia coli Isolates From a Tertiary Hospital in Sudan

“…On the other hand, ESBL producers were found to be rare in populations from Iran (21%) [ 9 ], Malaysia (24%) [ 25 ], Kermanshah, Iran (27.3%) [ 26 ], Saudi Arabia (23.1%) [ 27 ], Iraq (30.7%) [ 28 ], and only 6% in Libyans [ 29 ].…”

“…The E. coli isolates in this study were very resistant to ceftriaxone (81.7%), cefuroxime (81.7%), cefepime (100%), and ceftizoxime (90%) but not as resistant to meropenem (13.3%). Several studies have shown that E. coli isolates are resistant to many cephalosporines, such as cefotaxime, ceftriaxone, ceftizoxime, and cefepime [ 9 , 19 , 21 , 23 , 25 , 28 ]. However, other studies have shown that E. coli isolates are sensitive to meropenem [ 20 ].…”

“…On the other hand, a previous study found that CTX-M was only found in 6% of isolates and that SHV was not found at all [ 29 ]. Other researchers found that CTX-M and TEM were present in only 4% of their isolates [ 28 ]. Similar studies in our population [ 11 , 12 ] have found that TEM is common (61%) [ 5 ], and CTX-M and SHV are less common (38% and 37%, respectively) [ 11 , 12 ].…”