Comparative Characterisation of Genotypically Different Clones of MRSA in the Production of Biofilms

Abstract

<jats:p>The ability to adhere and produce biofilms is characteristic of enhanced virulence among isolates of methicillin-resistant<jats:italic>Staphylococcus aureus</jats:italic>(MRSA). The aim of the study is to find out whether these characteristics are consistently similar among isolates variations of MRSA. The study used 30 various isolates of MRSA belong to 13 spa types and 5 MLST types and determined the aggregation, the adherence, and the production of biofilms and slime for each isolate. The methods used to evaluate these characteristics were a modified Congo red agar assay (MCRA), a microtiter plate assay (MPA), high-magnification light microscopy, scanning electron microscopy (SEM), and PCR. The study found that isolates belonging to similar Spa, SCCmec, and ST types have similar abilities to produce biofilms; however, their ability to produce slime on CRA was found to be different. Moreover, isolates that have different Spa types showed high variation in their ability to produce biofilms. The results of light microscope revealed the isolates that produced strong and weak biofilms and formed similar aggregation on the glass surfaces. SEM results showed that all 30 MRSA isolates that were tested were 100% positive for biofilm formation, although to varying degrees. Further testing using PCR confirmed that 100% of the 30 isolates tested were positive for the presence of the<jats:italic>ica</jats:italic>ADBC,<jats:italic>fnbA, eno, ebps, clfA</jats:italic>, and<jats:italic>clfB</jats:italic>genes. The prevalence of<jats:italic>fib, cna, fnbB</jats:italic>, and<jats:italic>bbp</jats:italic>in MRSA clones was 90, 93.33, 53.33, and 10%, respectively. This study indicate that differences in biofilm production capacities are caused by the differences in surface protein A (Spa) type and are not due to differences in MLST and SCCmec types.</jats:p>

Methicillin-resistant Staphylococcus aureus biofilm formation on dacryocystorhinostomy silicone tubes depends on the genetic lineage

“…The ability to produce biofilms was not dependent on SCCmec, but on the lineage. This is in agreement with the findings of Atshan and associates [29].…”

Genetic diversity and biofilm formation analysis of Staphylococcus aureus causing urinary tract infections in Tehran, Iran

“…Their results showed that biofilm formation on polystyrene surfaces was associated with CC8 strains. In a study published in 2012 by Atshan et al comparing phenotypic and genotypic characteristics of biofilm producing S. aureus strains, the most common biofilm producers belonged to CC8 (53.3%) followed by CC1 (20%), CC22 (16.7%), and CC7 (10%) [35]. Their results also showed that all 30 MRSA isolates carried out icaADBC, fnbA, eno, ebps, clfA, and clfB genes.…”

Prevalence of Biofilm Formation Among Methicillin Resistance Staphylococcus aureus Isolated From Nasal Carriers

“…The chronic infections that cause by S. aureus, persist and increase the rate of morbidity and mortality in human population due to the development of biofilm structures produced by this pathogen (2). Biofilm forming bacteria are the cause of many nosocomial infections (3). According to some reports, over 65% of hospital-acquired infections occur by the infecting organisms that have the ability of producing biofilms (4).…”

“…Furthermore biofilm keeps bacteria out of reach of host immune defense mechanism and often resulting in persistent and difficult-to-treat infections (2,3). Methicillin resistant S. aureus (MRSA) that have the ability of biofilm formation can become resistant to the most currently use antibiotics (1).…”