Green synthesed silver nanoparticles from aloe vera leaves extract effect on gene expression of MEXZ and AAC6 genes in Pseudomonas aeruginosa isolates

In this study, hundred (100) specimens were collected from patients of both gender and different age groups in three government hospitals in Baghdad/Iraq from January 2022 to May 2022. Samples were diagnosed by routine, biochemical tests, and Vitek- 2 system device to diagnose the Pseudomonas aeruginosa, the results showed that 32 (32%) were P. aeruginosa bacteria. After that, the aac6 and mexZ genes were detected by polymerase chain reaction PCR technique and the results showed that 9 isolates (28%) carry the aac6 gene and 12 isolates (37.5%) carry the mexZ gene. Six isolates were selected to test the effectiveness of the AgNps Aloe vera leaves extract on it three isolates have the aac6 gene and three have mexz genes. All isolates demonstrated that the extract inhibited bacterial growth. after that, the study of the effectiveness of the AgNps Aloe vera leaves extract on gene expression. RNA was extracted from the six selected isolates before treatment with AgNps Aloe vera as control and after treatments with AgNps Aloe vera. The result of PCR showed down-regulation in the aac6 and mexZ gene expression levels under treatment hence the low level of gene expression in the mechanisms of resistance (modify enzyme, and efflux pumps).