Attenuation of alginate lyase by chlorhexidine in the alginate pathway of Pseudomonas aeruginosa biofilm formation

Ventilator-associated pneumonia (VAP) caused by Pseudomonas aeruginosa poses a significant clinical challenge due to the pathogen's robust
biofilm formation and resistance mechanisms. Chlorhexidine (CHX), a commonly used antiseptic, has shown potential in biofilm
inhibition, though its exact mechanism remains unclear. Our previous work focusing on quorum sensing associated proteins identified
strong CHX binding to PslG, a key protein in the Psl pathway. However, the potential for CHX interactions within other biofilm
pathways, such as alginate, has not been explored. This study explored CHX’s potential interaction with proteins involved in the alginate
pathway of P. aeruginosa biofilm formation using reverse docking. Structures of eight alginate-associated proteins were retrieved from
the Protein Data Bank. The CHX structure was obtained from PubChem and docking simulations were conducted using Fpocket and
SMINA to predict binding affinities. A total of 735 docking poses were generated for the analyzed alginate-associated proteins. Among
these, CHX showed the strongest binding affinity for alginate lyase, a key enzyme that degrades alginate and has been implicated as a
therapeutic target for biofilm disruption. This finding suggests that CHX may exert its anti-biofilm effects by targeting the alginate matrix
through alginate lyase, potentially enhancing biofilm degradation. Given the promising application of alginate lyase in biofilm control
strategies, the interaction between CHX and alginate lyase merits further experimental validation to explore its therapeutic impact in
clinical settings.