Evaluate the Effect of Zinc Oxide and Silver Nanoparticles on Biofilm and icaA Gene Expression in Methicillin-Resistant Staphylococcus aureus Isolated From Burn Wound Infection

Abstract

Methicillin-resistant Staphylococcus aureus is the cause of nosocomial and community-acquired infections. This study aimed to evaluate the effect of zinc oxide and silver nanoparticles (ZnO-Ag NPs) on biofilms formation and icaA gene expression in methicillin-resistant S. aureus (MRSA). In this study, three standard strains (ATCC 43300, 25923, and 29913) and a clinical isolate are included. The minimum inhibitory concentration (MIC) of nanoparticles was determined by microdilution broth method. The antibacterial effects of ZnO-Ag NPs either alone or in combination with each other were compared with vancomycin (as the control group). The effect of MIC and sub-MIC concentrations of ZnO-Ag NPs on biofilm formation was determined by the microtiter plate method. The expression level of the icaA gene was assessed by real-time PCR LightCycler® 96 software (Version 1.1.0.1320, Roche, Germany). technique. All experiments were repeated three times. Data were analyzed using SPSS software through ANOVA and t-test. The P-value of less than .05 was considered as statistically significant. The average MICs of ZnO, Ag, and ZnO-Ag NPs compounds were 393.2, 179.8, and 60.8 μg/ml, respectively. The compound of ZnO-Ag NPs had a synergistic effect against all isolates. ZnO-Ag NPs decreased the biofilm formation rate at MIC and sub-MIC concentrations (P < .001). Sub-MIC ZnO-Ag NPs concentration significantly reduced the icaA gene expression in S. aureus strains (P < .03). The sub-MIC concentration of ZnO-Ag NPs reduced biofilm formation rate and icaA gene expression in Staphylococcus aureus strains compared with vancomycin. It can be used to cover medical devices after examining more clinical isolates to prevent bacterial colonization.

The Decoration of ZnO Nanoparticles by Gamma Aminobutyric Acid, Curcumin Derivative and Silver Nanoparticles: Synthesis, Characterization and Antibacterial Evaluation

“…In comparison, CurBF2-AgNPs showed antibacterial activity against only S. aureus with inhibition zone of 7.33 ± 0.29 mm (Table 2). These results demonstrate that the combination of ZnO NPs with CurBF2-AgNPs gives a synergistic antibacterial effect [25] as compared to AgNPs or ZnO NPs alone.…”

“…Dhara, S. et al investigated the decoration of AgNPs on ZnO nanoflowers impregnated on eggshell membranes and Eshraghi et al reported the effect of the incorporation of ZnO and AgNPs on bacterial biofilms. These studies showed that AgNPs decorated on ZnO enhanced the latter's antimicrobial activity [24,25].…”

Effect of ZnO nanoparticles on methicillin, vancomycin, linezolid resistance and biofilm formation in Staphylococcus aureus isolates

“…However, Gheidar et al reported that the expression of icaA and icaD genes in the presence of ZnO-NPs were not significantly reduced compared to the control samples. But, exposure to nanoparticles reduced the expression of fnbA and fnbB genes from 0.46 to 0.06 [ 62 ].…”

Promising Antibiofilm Agents: Recent Breakthrough against Biofilm Producing Methicillin-Resistant Staphylococcus aureus

“…Only a recent study carried out in Iran documented that the sub-minimum inhibitory concentration of ZnO-Ag NPs significantly reduced the ica A gene expression in S. aureus strains [ 39 ]. Another study conducted in Korea evaluated the inhibitory effect of ZnO NPs on Pesudomonase aeruginosa biofilms genotypically [ 40 ], where the transcriptional and mutant data indicated that ZnO NPs inhibited Pesudomonase aeruginosa biofilm formation via the czcRS two-component system, which controls the QS-controlled phenotypes such as biofilm formation. This confirms the efficacy of ZnO NPs as an antibiofilm substance among a broad range of Gram positive and Gram negative bacterial isolates.…”