AIMS

This study aims to investigate how different wound microenvironmental factors (temperature, pH, and osmotic pressure) influence the autofluorescence of Staphylococcus aureus ( and its underlying molecular mechanisms, specifically focusing on the porphobilinogen synthase gene gene expression.

METHODS

We measured the average fluorescence intensity of colonies under varying conditions of pH (3, 5, 7, 9, 11), temperature (25°C, 31°C, 37°C, 43°C), and osmotic pressure (0.9%, 1.8%, 2.7%, 3.6%) over time. Fluorescence intensity was quantified using ImageJ software. Additionally, RT-qPCR was used to analyze the expression levels of the under these conditions.

RESULTS

Bacterial fluorescence intensity increased as the temperature ranged from 25°C to 43°C, with corresponding upregulation of expression. At pH values between 3 and 11, fluorescence intensity decreased as pH increased, reflecting a similar trend in expression. Fluorescence also diminished with higher osmotic pressures (0.9% to 3.6%), mirroring the downregulation of

CONCLUSIONS

Our findings indicate that temperature, pH, and osmotic pressure significantly affect the autofluorescence of by modulating porphyrin accumulation through gene expression. These environmental factors should be considered when using bacterial fluorescence for wound infection assessment.