Staphylococcus epidermidis is largely dependent on iron availability to form biofilms

Area of Science:

• Microbiology
• Bacterial Pathogenesis
• Biofilm Formation

Background:

• Staphylococcus epidermidis is a common skin colonizer and a significant nosocomial pathogen.
• Biofilm formation is a key virulence factor for S. epidermidis.
• The precise mechanisms regulating S. epidermidis biofilm formation require further investigation.

Purpose of the Study:

• To investigate the role of iron availability in modulating S. epidermidis biofilm formation.
• To elucidate the mechanisms by which iron affects biofilm development.

Main Methods:

• Cultivation of S. epidermidis biofilms under varying iron conditions (enriched, deficient, physiologic).
• Assessment of physiological and transcriptomic changes in biofilm cells.
• Temporal analysis of biofilm formation and structural changes.
• Evaluation of bacterial viability and cultivability.

Main Results:

• Iron excess or deficiency, but not physiologic levels, is detrimental to S. epidermidis biofilm formation.
• Planktonic cells are less affected by iron availability compared to biofilm cells.
• Iron deficiency significantly compromises biofilm cell viability and cultivability.
• Altered iron levels impair biomass accumulation and biofilm structure from early stages.
• Expression of iron-related genes, including those for siderophore biosynthesis, is modulated by iron availability.

Conclusions:

• Iron availability plays a critical and multifaceted role in Staphylococcus epidermidis biofilm formation.
• Iron homeostasis is essential for maintaining biofilm integrity, viability, and development.
• Modulation of iron-related gene expression provides insights into S. epidermidis iron metabolism during biofilm growth.