Improved lux reporters for use in Staphylococcus aureus

Area of Science:

• Microbiology
• Molecular Biology
• Biotechnology

Background:

• The luxABCDE reporter system offers real-time signal generation without exogenous substrates, unlike lacZ or xylE.
• Bacterial luminescence in Staphylococcus spp. can be limited by endogenous fatty acid aldehyde availability.

Purpose of the Study:

• To construct novel promoterless lux reporter cloning vectors, pGYlux and pAmilux.
• To enhance lux-based reporter gene expression in Staphylococcus aureus.

Main Methods:

• Construction of promoterless lux cloning vectors pGYlux and pAmilux.
• Fusion of B. subtilis xyl/tetO promoter to lux genes in pGYlux.
• Cloning of the constitutive ami promoter upstream of luxCDE genes in pAmilux.

Main Results:

• S. aureus with pGYlux showed a 2.5-fold luminescence enhancement compared to the parent vector pAL2.
• pAmilux demonstrated a 6-fold enhancement in lux expression over pGYlux in S. aureus.
• The ami promoter increased endogenous fatty acid aldehyde production, boosting reporter function.

Conclusions:

• pGYlux and pAmilux are effective promoterless lux reporter vectors.
• pAmilux significantly enhances luminescence in S. aureus by optimizing substrate availability.
• These vectors provide improved tools for real-time monitoring of gene expression in bacteria.