CORRInsights®: Does Extracellular DNA Production Vary in Staphylococcal Biofilms Isolated From Infected Implants versus Controls?
In their current study, Zatorska and colleagues found that Staphylococcus aureus and S epidermidis had differential production of eDNA with time. The difference could be due to the mechanism of eDNA release in both strains. For example, S aureus eDNA originates from cell lysis and constitutes a necessary part of biofilm development; whereas for S epidermidis, the autolysin protein AtlE mediates eDNA release and biofilm initiation.
The most-important finding of this study is that clinical isolates of S aureus and S epidermidis produced substantially more eDNA than nonclinical control isolates. Interestingly, a previous study  demonstrated that clinical strains of S epidermidis and the biofilm forming strain RP62A produced an abundance of eDNA compared to weak biofilm forming strains. Another study  examining 55 clinical isolates of S epidermidis from postsurgical and biomaterial-related orthopaedic infections showed remarkable eDNA variability. These findings indicate the presence of eDNA and its structural role in the development of biofilms in clinical strains.