The Synthesis of L-Alanyl and β-Alanyl Derivatives of 2-Aminoacridone and Their Application in the Detection of Clinically-Important Microorganisms

A Selective, Dual Emission β-Alanine Aminopeptidase Activated Fluorescent Probe for the Detection of Pseudomonas aeruginosa, Burkholderia cepacia, and Serratia marcescens

Selective detection of β-alanyl aminopeptidase (BAP)-producing Pseudomonas aeruginosa, Serratia marcescens, and Burkholderia cepacia was achieved by employing the blue-to-yellow fluorescent transition of a BAP-specific enzyme substrate, 3-hydroxy-2-(p-dimethylaminophenyl)flavone derivative, incorporating a self-immolative linker to β-alanine. Upon cellular uptake and accumulation of the substrate by viable bacterial colonies, blue fluorescence was generated, while hydrolysis of the N-terminal peptide bond by BAP resulted in the elimination of the self-immolative linker and the restoration of the original fluorescence of the flavone derivative.

Fluorescent nitric oxide donor for the detection and killing of Pseudomonas aeruginosa

The epidemic of multidrug-resistant bacteria calls for the improvement of both detection methods for bacterial infections and methods of treatment. Nitric oxide is a known potent antibacterial agent, but due to its gaseous and highly reactive nature, it is difficult to incorporate into a stable antibacterial compound. In this paper, we synthesize a nitric oxide donor attached to a fluorescent compound, creating a material that can both detect and kill the deadly multi-drug resistant bacteria strain Pseudomonas aeruginosa. Detection occurs through a bacterial enzyme-activated color change, showing a clear and obvious change from blue to yellow under UV light. The synthesized compound spontaneously releases 853 μmol of nitric oxide/g from a 10 mM initial concentration. Antibacterial efficacy studies after exposing Pseudomonas aeruginosa to a 10 mM dose of the synthesized compound show a 55-75% reduction in bacteria after 24 hours. This work is the first instance of a small molecule dual-function material that can both detect and kill bacteria.