Identification and functional characterization of a novel Acinetobacter pittii bacteriophage-encoded depolymerase

Area of Science:

• Microbiology
• Biotechnology
• Infectious Diseases

Background:

• Acinetobacter pittii is a growing cause of hospital-acquired infections.
• Bacteriophage depolymerases targeting capsular polysaccharides (CPS) are potential therapeutics.

Purpose of the Study:

• To identify and characterize a novel depolymerase, 31TSP, from Acinetobacter pittii bacteriophage 31Y.
• To evaluate 31TSP's stability, efficacy against biofilms, and synergistic potential with antibiotics.

Main Methods:

• Depolymerase 31TSP was isolated and characterized for functional stability (pH, temperature, NaCl).
• Biofilm inhibition and disruption were assessed using crystal violet staining, cell counts, and SEM.
• Combinatorial treatments with 31TSP and ampicillin were evaluated.

Main Results:

• 31TSP demonstrated broad host range and degraded CPS in Acinetobacter species.
• The enzyme was stable across a wide pH (5-11) and temperature (4-121°C) range.
• 31TSP inhibited biofilm formation and disrupted preformed biofilms, with enhanced effects when combined with ampicillin.

Conclusions:

• 31TSP shows promise as an antibacterial agent against Acinetobacter infections.
• Synergy with ampicillin suggests a viable combinatorial therapeutic strategy.
• Stability under extreme conditions supports therapeutic potential, but ionic instability requires further study.