Find in Library

The protease &#945;-chymotrypsin (&#945;-CT) was covalently immobilized on a low-density polyethylene (LDPE) surface, providing a new non-leaching material (LDPE-&#945;-CT) able to preserve surfaces from biofilm growth over a long working timescale. The immobilized enzyme showed a transesterification activity of 1.24 nmol/h, confirming that the immobilization protocol did not negatively affect &#945;-CT activity. Plate count viability assays, as well as confocal laser scanner microscopy (CLSM) analysis, showed that LDPE-&#945;-CT significantly impacts <i>Escherichia coli</i> biofilm formation by (i) reducing the number of adhered cells (&#8722;70.7 &#177; 5.0%); (ii) significantly affecting biofilm thickness (&#8722;81.8 &#177; 16.7%), roughness (&#8722;13.8 &#177; 2.8%), substratum coverage (&#8722;63.1 &#177; 1.8%), and surface to bio-volume ratio (+7.1 &#177; 0.2-fold); and (iii) decreasing the matrix polysaccharide bio-volume (80.2 &#177; 23.2%). Additionally, CLSM images showed a destabilized biofilm with many cells dispersing from it. Notably, biofilm stained for live and dead cells confirmed that the reduction in the biomass was achieved by a mechanism that did not affect bacterial viability, reducing the chances for the evolution of resistant strains.