Metabolically Specific In Situ Fluorescent Visualization of Bacterial Infection on Wound Tissues.

Area of Science:

• Biomedical Imaging
• Microbiology
• Drug Discovery

Background:

• Effective bacterial infection detection is crucial for timely treatment.
• Current methods struggle with in situ, target-specific visualization of bacteria on host cells.
• Bacterial dihydropteroate synthase (DHPS) is a unique enzyme in bacterial folic acid synthesis.

Purpose of the Study:

• To develop a novel fluorescent imaging probe for specific bacterial detection.
• To target the bacterium-specific DHPS enzyme and its metabolic pathway.
• To enable in situ visualization of bacterial infections in target tissues.

Main Methods:

• Conjugation of p-aminobenzoic acid (PABA) with dicyanomethylene 4H-pyran (DCM) to create the PABA-DCM probe.
• Validation of DHPS-mediated catalysis and increased folic acid levels in bacteria.
• Development of a hydrogel dressing (PABA-DCM@GO) for wound imaging in mice.

Main Results:

• PABA-DCM targets DHPS, showing extended retention in bacterial cells over mammalian cells.
• The probe's catalytic conversion by DHPS increases bacterial folic acid levels.
• PABA-DCM@GO hydrogel enabled specific fluorescence visualization of bacterial infections on mouse wound tissues.

Conclusions:

• PABA-DCM is an effective fluorescent probe for targeting bacterial DHPS.
• The PABA-DCM@GO hydrogel facilitates in situ monitoring of bacterial infections.
• This approach offers a new strategy for developing imaging agents targeting conserved microbial metabolic pathways.