Investigating The Impact Of Melittin On BAP, Gene Expression In Acinetobacter Baumannii Using Real-Time PCR

Abstract

Background: Due to increasing antibiotic resistance to A.baumannii, there is an urgent need to find new antibiotic alternatives or supporters for the treatment of disease-causing pathogens. For the past 30 years, strains of A. baumannii have acquired resistance to newly developed antimicrobial drugs.Therefore, melittin was used as an experimental treatment, Melittin, considered to be an antimicrobial, antitumor, and anti-inflammatory peptide.

Objective: The objective of this study was to investigation the effectiveness melittin extract from bee venom against A. baumannii through genetic expression of the Bap genes by using a qRT-PCR and detection biofilm formation by quantitative assay via Micro-titer plate method in Karbala city.  

Methods:Two hundred different Clinical specimens were collected from various sources from patient who admitted to Imam Hussein Medical City, the study beginning from the period January 2024 till the August 2024. The  specimens which included sputum, wound, urine, blood and fluid and all specimens was collected as 40 cases.

Melittin was extracted from local bee venom via HPLC and detection of the standard compound and the isolated compound was performed, along with FTIR spectrum analysis. Detection biofilm formation before and after melittin treatment by quantitative assay via Micro-titer plate method divided into three groups(strong biofilm, moderate biofilm and weak biofilm). Also done estimating the effectiveness of melittin extract as anti-bacterial through genetic expression of the Bap gene by using qRT-PCR.

Results: The collection specimens from patients included 40(20%) positive specimens distributed as 25 (62.5%) from females, and 15 (37.5%) from males and they were divided into: 17(42.5%) sputum, 10(25%) wound, 7(17.5%) urine,5(12.5%) blood ,1(2.5%) fluid specimens. After cultured on Blood agar and MacConkey agar, the isolates were identified via VITIK 2 compact system (Biomérieux, France). All isolates were tested for their resistance to 18 different antibiotics and the results exhibited that highest level of resistance in A.baumannii isolates to total antibiotics used in this study except Minocycline, Colistin and Tigecycline . Our study showed the Colistin, Minocycline and Tigecycline were sensitive in the rate36 (90%), 35 (87.5)and 30(75%) respectively. After melittin treatment The absorbance value for strong biofilm formation decreased to 52%, absorbance value for moderate biofilm formation was reduced to %55 indicating a substantial decrease in biofilm density and absorbance value for weak biofilm formation was recorded 24% showing a slight reduction compared to the pre-treatment measurements. The result of Bap gene expression exhibited  strong biofilm formation 77% ,moderate biofilm formation 57% and weak biofilm formation 74%.

Conclusion : The study concluded that the most common cases of infection with A.baumannii bacteria in sputum, and that this bacteria has a high resistance to most antibiotics.