Alginate hydrogels loaded with pyruvate dehydrogenase enzyme: a novel wound dressing to disassemble Pseudomonas aeruginosa biofilm

Topical wounds require effective dressings to manage wound exudate, maintain moisture, and avoid infection. Alginate hydrogels are widely used clinically due to their biocompatibility, high absorbency, and ability to maintain a moist wound environment during healing; however, alginate can also promote bacterial biofilm formation and prolong healing. Depleting pyruvate using the enzyme pyruvate dehydrogenase (PDH) has been shown in both in vitro and in vivo studies to effectively disrupt biofilm structure. This study entraps PDH in alginate hydrogels to disperse/disassemble biofilms formed by a prevalent wound pathogen, Pseudomonas aeruginosa. PDH depletes pyruvate and alters the biofilm metabolism, resulting in the prevention and dispersion of biofilms. Alginate hydrogels exhibited compressive moduli ranging from 15 to 80 kPa, with the water content of all swollen hydrogels exceeding 90%, and demonstrated structural stability in simulated wound exudate. PDH loading of 0.85 U in 65 {micro}l of alginate achieved maximum observed enzymatic activity, 60% of which was retained after six days. Notably, PDH-loaded hydrogels significantly reduced biofilm biomass by 40.94% {+/-} 6.07 compared to media alone and by 80.05% {+/-} 6.37 compared to the Dimora(R) commercial alginate dressing. Furthermore, PDH-entrapped alginate hydrogels significantly reduce biofilm biomass without affecting the viability of human dermal fibroblasts, highlighting the commercial potential of the material. The successful integration of a biofilm metabolism-altering enzyme within wound dressings presents a promising avenue for improving chronic wound management and reducing the burden of biofilm-associated infections without the need for the discovery of new antibiotic drugs. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=149 SRC="FIGDIR/small/661844v1_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@1fe58bforg.highwire.dtl.DTLVardef@1748051org.highwire.dtl.DTLVardef@19453eborg.highwire.dtl.DTLVardef@111a9b6_HPS_FORMAT_FIGEXP M_FIG C_FIG