Microbial prodigiosin shows broad-spectrum bioactivity confirmed by experimental and computational analyses

Area of Science:

• Microbiology
• Biochemistry
• Natural Products Chemistry

Background:

• Growing demand for natural bioactive compounds necessitates exploration of microbial metabolites.
• Prodigiosin, a pigment from Serratia marcescens, exhibits promising antioxidant and antimicrobial properties.
• Challenges exist in optimizing prodigiosin production and understanding its molecular mechanisms.

Purpose of the Study:

• To optimize the production of prodigiosin using peptone meat extract (PM) media.
• To characterize the purified prodigiosin and evaluate its bioactivity.
• To elucidate the molecular interactions underlying prodigiosin's bioactivity through molecular docking.

Main Methods:

• Optimized prodigiosin production using PM media at 30 °C.
• Purified and characterized prodigiosin using chromatography, UV-Vis, FT-IR, and ESI-MS/MS.
• Assessed antibacterial, antifungal, and antioxidant activities.
• Performed molecular docking studies against target enzymes (FKS1, FabH, Keap1).

Main Results:

• Optimized conditions yielded enhanced prodigiosin production.
• Characterization confirmed the pigment as prodigiosin (R_f 0.93, λ_max 536 nm, m/z 324.3 amu).
• Prodigiosin demonstrated broad-spectrum activity against E. coli, B. subtilis, F. oxysporum, and A. niger, with significant radical-scavenging activity.
• Molecular docking revealed high binding affinities with FKS1 (-7.2 kcal/mol), FabH (-7.3 kcal/mol), and Keap1 (-8.3 kcal/mol).

Conclusions:

• Optimized production of prodigiosin from Serratia marcescens was achieved.
• Prodigiosin exhibits potent antimicrobial and antioxidant properties.
• Molecular docking provides insights into prodigiosin's mechanism of action, supporting its development as a natural therapeutic agent.