title: Evaluation of AgClNPs@SBA-15/IL nanoparticle-induced oxidative stress and DNA mutation in Escherichia coli.
abstract: The bactericidal effects of silver nanoparticles have been demonstrated in the past years. Recently, the new antimicrobial compounds of silver nanoparticles with different formulations have been developed. In this work, AgClNPs@SBA-15/IL as a new compound of Ag nanoparticles, was synthesized and characterized by XRD, TEM, SEM, FTIR, and EDX. The antibacterial activity and the molecular mechanism effects of AgClNPs@SBA-15/IL nanoparticles (SNPs) on Escherichia coli DH5α cells were investigated by analyzing the growth inhibitory, H2O2 level, catalase activity, DNA mutation, and plasmid copy number following treatment with AgClNPs@SBA-15/IL nanoparticles. In experimental results, the minimum inhibitory concentration (MIC) was observed in 75 μg/ml and the antibacterial efficacy (ABE) in CFU analysis was estimated 95.3 %. In bacterial cells treated with 75 and 100 μg/ml, H2O2 level significantly increased and catalase activity decreased compared with control. The random amplified polymorphic DNA (RAPD) was used to evaluate the effect of AgClNPs@SBA-15/IL nanoparticles in DNA damages and mutation in E. coli genome. RADP-PCR results indicated different banding patterns including appearance or disappearance of bands and differences in their intensity. Cluster analysis of the RAPD-PCR results based on genetic similarity showed genetic difference between E. coli cells treated with AgClNPs@SBA-15/IL nanoparticles, and control and phylogenetic tree were divided to two clusters. Plasmid copy number analysis indicated that after 8 h incubation of E. coli cells with 50, 75, and 100 μg/ml AgClNPs@SBA-15/IL nanoparticles, copy number of pET21a (+) significantly decreased compared with control which indicating DNA replication inhibition by Ag nanoparticles. In conclusion, the results of this study indicated that AgClNPs@SBA-15/IL nanoparticles can be used as an effective bactericidal agent against bacterial cells.
authors.affiliation: Department of Biology, Faculty of Science, University of Maragheh, P.O. Box 55181-83111, Maragheh, Iran. karimifm@maragheh.ac.ir.
authors.forename: Farrokh
authors.initials: F
authors.lastname: Karimi
authors.affiliation: Department of Biology, Faculty of Science, University of Maragheh, P.O. Box 55181-83111, Maragheh, Iran.
authors.forename: Somayyeh
authors.initials: S
authors.lastname: Dabbagh
authors.affiliation: Department of Biology, Faculty of Science, University of Maragheh, P.O. Box 55181-83111, Maragheh, Iran.
authors.forename: Sina
authors.initials: S
authors.lastname: Alizadeh
authors.affiliation: Department of Chemistry, Faculty of Science, University of Maragheh, Box 55181-83111, Maragheh, Iran.
authors.forename: Sadegh
authors.initials: S
authors.lastname: Rostamnia
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D004261:DNA Replication / Q000187:drug effects*; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D006861:Hydrogen Peroxide / Q000378:metabolism; D053768:Metal Nanoparticles; D008826:Microbial Sensitivity Tests; D009154:Mutation / Q000187:drug effects; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D010957:Plasmids / Q000235:genetics; D019105:Random Amplified Polymorphic DNA Technique; D012822:Silicon Dioxide / Q000494:pharmacology*; D018030:Silver Compounds / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; C509969:SBA-15; D018030:Silver Compounds; D012822:Silicon Dioxide; D006861:Hydrogen Peroxide; D002374:Catalase; C037548:silver chloride
keywords: AgClNPs@SBA-15/IL; DNA mutation; Escherichia coli; Oxidative stress