Igwe JC, Olayinka BO, Ehnimidu JO and Onaolapo JA
Multidrug resistant (MDR) E. coli associated infections remains one of the most important bacterial infections that have contributed significantly to increased morbidity and mortality in clinical settings. One of the known resistant mechanisms of MDR bacteria is reduced cell wall permeability, which is controlled by outer membrane protein OmpF and OmpC. This study evaluates the difference in molecular weight of outer membrane protein of MDR E. coli isolated from UTI and diarrhoeic patients in Zaria, Nigeria and antibiotic susceptible ATCC29522 strain using standard microbiological and molecular techniques. Eighty seven (87) confirmed E. coli isolates from UTI and diarrhoeic patients in selected hospitals in Zaria, Nigeria were evaluated for MDR using 15 antibiotics commonly prescribed for E. coli associated infections. The results showed that the 21 suspected multidrug isolates were 100% susceptible to Imipenem and Amikacin, and 71.4 % susceptible to Nitrofurantoin but highly (100%) resistant to Amoxicillin, Ofloxacin, Ciprofloxacin, Cefpodoxime and Ceftaxime, 95.2% resistant to Cefpirome, 85.7% to Tetracycline and Sulphamethonidazole-Trimethroprim, 76.2% to Gentamicine, 66.7% to Chloramphenicol, 61.9% to Aztreonam and 57.1% to Ceftriaxone. Cell wall protein evaluation using SDS-PAGE showed that both the MDR isolates and susceptible strain had equal OmpC bands at 38kDa while the OmpF varied from one MDR isolate to another compared with the ATCC29522 used as control. This study contributes to other findings that a decrease in cell wall outer protein OmpF could contribute to high resistance to antibiotics.