Molecular Biological Studies of the Agar A Gene in Staphylococcus Aureus (MRSA) and the Discovery of the Association Between Its Gene Expression and Biofilm Formation in Iraqi Patients

Sufyan Riyadh Farhan; Eyüp  Bağci

doi:10.51699/cajmns.v7i3.3308

Authors

Sufyan Riyadh Farhan Biology Department, College of Science, Firat University, Turkey
Eyüp Bağci Biology Department, College of Science, Firat University, Turkey

DOI:

https://doi.org/10.51699/cajmns.v7i3.3308

Keywords:

Staphylococcus Aureus, MRSA, PCR, Agr A, Biofilm, Blood agar

Abstract

Background :From an epidemiological standpoint, MRSA is generally classified into three types based on its origin and prevalence. Each of these types has evolved in different contexts and has its own unique genomic profile . The three types of MRSA are healthcare-associated MRSA (HA-MRSA) . community-associated MRSA (CA-MRSA) . and livestock-associated MRSA (LA-MRSA). Methodology : Samples such as urine, semen, and other bodily fluids were collected from patients. These samples were cultured on mannitol agar and blood agar. After bacterial growth, the bacteria were identified using the VITEK system and tested for methicillin resistance. Bacterial DNA was extracted using a dedicated extraction kit, and gene expression was measured using polymerase chain reaction (PCR).Results : The results of the relationship between bacteria isolated from different body samples and their resistance or sensitivity to the antibiotic methicillin were recorded as follows: 77.8% of the isolated bacteria were methicillin-resistant and distributed across three groups according to the source of isolation, while 22.2% were sensitive, Gene expression analysis revealed that methicillin-resistant bacteria showed increased gene expression in biofilm-producing bacterial samples. Aims od study : The purpose of this study is to clarify the relationship between methicillin-resistant bacteria (MRSA) and Agr A gene expression, and whether this relationship is direct or inverse, that is, whether increased biofilm formation leads to increased gene expression. Conclusion: Staphylococcus aureus (MRSA) strains using modern diagnostic methods such as polymerase chain reaction (PCR). This study demonstrated a correlation between biofilm formation in two strains—methicillin-resistant and methicillin-susceptible—in different patient samples. Additionally, a positive correlation was observed between the gene, Agr A, and biofilm formation in this strain.

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