Effects of Lysozyme, Proteinase K, and Cephalosporins on Biofilm Formation by Clinical Isolates of Pseudomonas aeruginosa

Abstract

Pseudomonas aeruginosa is an opportunistic pathogen that can form biofilms, which confer resistance to immune clearance and antibacterial treatment. Therefore, effective strategies to prevent biofilm formation are warranted. Here, 103 P. aeruginosa clinical isolates were quantitatively screened for biofilm formation ability via the tissue culture plate method. The effects of lysozyme (hydrolytic enzyme) and proteinase K (protease) on biofilm formation were evaluated at different concentrations. Lysozyme (30 μg/mL), but not proteinase K, significantly inhibited biofilm formation (19% inhibition). Treatment of 24-hour-old biofilms of P. aeruginosa isolates with 50 times the minimum inhibitory concentrations (MICs) of ceftazidime and cefepime significantly decreased the biofilm mass by 32.8% and 44%, respectively. Moreover, the exposure of 24-hour-old biofilms of P. aeruginosa isolates to lysozyme (30 μg/mL) and 50 times MICs of ceftazidime or cefepime resulted in a significant reduction in biofilm mass as compared with the exposure to lysozyme or either antibacterial agent alone. The best antibiofilm effect (49.3%) was observed with the combination of lysozyme (30 μg/mL) and 50 times MIC of cefepime. The promising antibiofilm activity observed after treatment with 50 times MIC of ceftazidime or cefepime alone or in combination with lysozyme (30 μg/mL) is indicative of a novel strategy to eradicate pseudomonal biofilms in intravascular devices and contact lenses.

Purification, Characterization, and Biocatalytic and Antibiofilm Activity of a Novel Dextranase from Talaromyces sp.

“…e effect of enzyme addition on old-established biofilm was previously documented [47]. In our study, the use of 5 units of the enzyme had 86% reducing activity on 24 h old-established biofilm of P. aeruginosa strain PAO1, adhering to the wall of the microtiter plate ( Figure 10).…”

Clinical Biofilm Ring Test® Reveals the Potential Role of β-Lactams in the Induction of Biofilm Formation by P. aeruginosa in Cystic Fibrosis Patients

“…This tissue culture plate method initially assessed the quantification of biofilm by the bacteria categorization according to their adhesion strength, as for the cBRT device. Eladawy et al evaluated the potential preventive effect of lysozyme and proteinase K on the biofilm of a collection of 103 P. aeruginosa clinical isolates [ 19 ]. Among them, an analysis of 13 strains originated from sputum through CV assay revealed that 10 were even strongly-adherent, 3 moderately-adherent, and 1 weakly-adherent.…”

Promising Therapeutic Strategies Against Microbial Biofilm Challenges

“…Dispersin B was used as one of the components in multilayer coatings and exhibited high antibiofilm efficiency with high stability (Pavlukhina et al, 2012 ). Many other enzymes, such as proteinase K and lysozyme, have been proven to have promising antibiofilm activity (Eladawy et al, 2020 ). These biofilm-dispersing enzymes have better antimicrobial activities when administered in combination with antimicrobial agents (Darouiche et al, 2009 ; Rodríguez-López et al, 2017 ; Kim et al, 2019 ; Eladawy et al, 2020 ).…”

“…Many other enzymes, such as proteinase K and lysozyme, have been proven to have promising antibiofilm activity (Eladawy et al, 2020 ). These biofilm-dispersing enzymes have better antimicrobial activities when administered in combination with antimicrobial agents (Darouiche et al, 2009 ; Rodríguez-López et al, 2017 ; Kim et al, 2019 ; Eladawy et al, 2020 ). Researchers have also tried different enzyme combinations (Karygianni et al, 2020 ) or dispersal-inducing enzymes combined with other new technologies, such as nanotechnology (Patel et al, 2019 ; Tasia et al, 2020 ), to improve antimicrobial biofilm activity and achieve good results.…”