Structural Properties Dictating Selective Optotracer Detection of Staphylococcus aureus.

Area of Science:

• Biochemistry
• Microbiology
• Materials Science

Background:

• Optotracers are fluorescent molecules designed for detecting biopolymers like peptides and carbohydrates.
• Selective detection of bacterial species, such as Staphylococcus aureus (S. aureus), remains a challenge in diagnostics.

Purpose of the Study:

• To investigate the structural properties of optotracers for optimal detection of S. aureus.
• To enhance the photophysical properties of optotracers for improved bacterial imaging.

Main Methods:

• Quantification of spectral shifts and fluorescence intensity using automated peak analysis, cross-correlation, and area-under-curve analysis.
• Investigation of factors like conjugated backbone length and charged group distribution in optotracers.
• Incorporation of donor-acceptor-donor (D-A-D) motifs to modify optotracer photophysics.

Main Results:

• Conjugated backbone length and the number of charged groups significantly influence S. aureus detection.
• Donor-acceptor-donor motifs substantially improved optotracer photophysical properties, reducing background noise.
• Enhanced optotracers demonstrated a binding-induced fluorescence on-switch, enabling real-time S. aureus growth monitoring.

Conclusions:

• Chemical structure and photophysical properties are critical, tunable characteristics for developing specific bacterial detection optotracers.
• Optimized optotracers provide a promising tool for selective and real-time visualization of S. aureus.