Dose-dependent effect of lysozyme upon Candida albicans biofilm

Abstract

The present study investigated the in vitro effect of lysozyme (0–1,000 µg/ml) on Candida albicans (C. albicans) biofilm development. Investigations were conducted on C. albicans ATCC 10231 and on 10 clinical isolates from dentures. Strains were cultured aerobically at 37°C in Sabouraud broth. Yeast growth was evaluated by turbidimetry. Biofilm biomass was quantified on a polystyrene support by crystal violet staining and on acrylic surfaces by counts of colony forming units. Lysozyme affected biofilm formation to a greater extent than it affected growth. For the ATCC 10231 reference strain, lysozyme acted as a biofilm promotor on polystyrene at the highest concentration tested (1,000 µg/ml, non-physiological). When the reference strain was investigated on acrylic resin support, lysozyme acted as a significant biofilm promotor on rough resin, but less on smooth resin. The attached biomass in the presence of physiological concentrations of lysozyme (10–30 µg/ml) was significantly decreased compared with the hypothetical value of 100% using a one-sample t-test, but a comparison between the different lysozyme conditions using analysis of variance and post hoc tests did not reveal significant differences. In 10 wild strains, different patterns of biofilm formation on polystyrene were observed in the presence of lysozyme. Some strains, characterized by large amounts of biofilm formation in the presence of 1,000 µg/ml lysozyme, were poor biofilm producers at low concentrations of lysozyme. In contrast, some strains that were poor biofilm producers with a high lysozyme concentration were more inhibited by low concentrations of lysozyme. The present study emphasizes the need to develop strategies for biofilm control based on in vitro experiments, and to implement these in clinical trials prior to approval of hygiene products enriched with exocrine proteins, such as lysozyme. Further studies will extend these investigations to other Candida species, and to fungi and bacteria present in oral biofilms.

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

“…Lysozyme and proteinase K are capable of inhibiting the biofilm formation ability of many bacterial species [19,33,44]. Lysozyme is present in physiological secretions at concentrations between 10 and 30 μg/mL [33].…”

“…Lysozyme and proteinase K are capable of inhibiting the biofilm formation ability of many bacterial species [19,33,44]. Lysozyme is present in physiological secretions at concentrations between 10 and 30 μg/mL [33]. Nonphysiological concentrations of lysozyme (greater than 30 μg/mL) was shown to enhance biofilm formation of P. aeruginosa [19] and Candida albicans [33].…”

“…Lysozyme is present in physiological secretions at concentrations between 10 and 30 μg/mL [33]. Nonphysiological concentrations of lysozyme (greater than 30 μg/mL) was shown to enhance biofilm formation of P. aeruginosa [19] and Candida albicans [33]. erefore, we investigated the effect of lysozyme on biofilm formation at concentrations ≤30 μg/mL.…”

“…To investigate the effect of lysozyme on the viability of P. aeruginosa planktonic cells, two representative strongly adherent isolates (E4 and B3 isolates) were subcultured in TSBG alone or with lysozyme (30 μg/mL). Cultures were incubated in a shaking incubator at 37°C, and their viability was investigated every hour by measuring OD 600nm for a total of 16 h [19,33].…”

Antifungal Activity of Human and Some Mammals Sera

“…Лизоцим при взаимодействии с клетками C. albicans оказывает литическое действие на клеточную стенку и цитоплазматическую мембрану [13]. Человеческие РНКазы легко связываются с мембраной клеток C. albicans, что приводит к деполяризации и разрушению мембраны.…”