The WHO and CDC have expressed serious concern regarding the continued increase in the development of multidrug resistance among bacteria. Associated with the rise in antibiotic resistance is the lack of new antimicrobials. Bacteria have developed many ways by which they become resistant to antimicrobials among those are enzymes. Aminoglycosides play an important role in treatment of serious infections that threat human life caused by Gram-negative bacteria (GNB). In our study, clinical bacterial isolates(210) were collected from different Egyptian hospitals. Eight aminoglycoside antibiotics were used in the present study. The most prevalent pathogen were E. coli (36.66%),E.coli-ESBL(5.23%),Klebsiella spp. (25.33%), Klebsiella spp.-ESBL (1.90%),Pseudomonas spp.(17.61%), Acinetobacter spp. (8.09%),Proteus spp. (2.85%),Enterobacter spp.(1.42%) and (0.47%) for both of Citrobacter sp. and Morganella sp. The most efficiency aminoglycoside antibiotic was Amikin(AK) and the resistance pattern increased over the last years in Egypt. The results of AME-genes indicated that non of aac(3′)-Ia and Rmt(55) genes were detected in any of the thirty Klebsiella spp. and E. coli of Egyptian isolates. The most prevalent AME-genes were aac(3′)-IIa(40%),aac(6′)-Ib (30%) followed by aph(3′)-Ia (23.3%),ant(2″)-Ia(20.0%),aph(3′)-VI(13.3%),and aac(3′)-Ih(6.6%). Also, the results revealed that isolate Klebsiella sp. MAM-16 acquired five AME genes aac(3′)-IIa (accession no. MF495896); acc(3′)-Ih (accession no. MF 495898); aph(3′)-VI(accession no. MF495899); ant(2″)-Ia (accession no. MF495901) and aph(3′)-Ia (accession no. MF495903). E. coli MAM-24 also acquired five AME-genes aac(3′)-IIa (accession no. MF495897); aph (3′)-VI(accession no. MF495900); ant(2″)-Ia (accession no. MF495902); aph(3′)-Ia(accession no. MF495904) and acc(6′)-Ib (accession no. MF495905).
The present study was carried out to explore the potential of the isolated bacterial strains isolated from Gabal El Sela in Eastern Dessert, Egypt for biosynthesis of uraninite nanoparticles intracellularly. The most potent bacterial strains associated (intra) with uranium nanoparticles were characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) and Energy Dispersive X-ray (EDX). Studying factors affecting biosynthesis of uranium nanoparticles indicated that the optimum conditions were 6000 ppm uranium concentrations at pH 7.0 and temperature 30 °C ± 1 after five days with 10% biomass under shaking conditions and the maximum uranium uptake by MAM - U9 cells was 3300 ppm (55%) from uranyl nitrate solution and 3600 ppm (72%) from Sela rock sample. Results of TEM micrograph show those uranium nanoparticles (UNPs) with size ranging from 2.9 to 21.13 nm inside cells. The kinetics, isotherm and thermodynamics parameters of uranium uptaken by bacterial strain MAM -U9 have been determined and found to be a first order process (R = 9935), follows Langmuir isotherm (R = 0.998) and the thermodynamics of ΔG = -9.715 kJmol, ΔH = 16.987 kJmol and ΔS = 0.0881 kJmolK at 30 °C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.