The Role of msa in Staphylococcus aureus Biofilm Formation.
BACKGROUND
Staphylococcus aureus is an important pathogen that forms biofilms. The global regulator sarA is essential for biofilm formation. Since the modulator of sarA (msa) is required for full expression of sarA and regulates several virulence factors, we examined the capacity of the msa mutant to form biofilm.


RESULTS
We found that mutation of msa results in reduced expression of sarA in biofilm and that the msa mutant formed a weak and unstable biofilm. The msa mutant is able to adhere to surfaces and begins to form biofilm but fails to mature indicating that the defect of the msa mutant biofilm is in the accumulation stage but not in primary adhesion.


CONCLUSIONS
The msa gene plays an important role in biofilm development which is likely due to its role in modulating the expression of sarA. This finding is significant because it identifies a new gene that plays a role in the development of biofilm.
Sambanthamoorthy
Karthik
K
Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406-0001, USA. ksambant@wpahs.org
Schwartz
Antony
A
Nagarajan
Vijayaraj
V
Elasri
Mohamed O
MO
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation / Q000235:genetics; D013211:Staphylococcus aureus / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism
D001426:Bacterial Proteins; C088021:SarA protein, bacterial; D015534:Trans-Activators