Single DNase or Proteinase Treatment Induces Change in Composition and Structural Integrity of Multispecies Oral Biofilms

Abstract

Biofilm virulence is mainly based on its bacterial cell surrounding biofilm matrix, which contains a scaffold of exopolysaccharides, carbohydrates, proteins, lipids, and nucleic acids. Targeting these nucleid acids or proteins could enable an efficient biofilm control. Therefore, the study aimed to test the effect of deoxyribonuclease I (DNase I) and proteinase K on oral biofilms. Six-species biofilms (Streptococcus mutans, Streptococcus oralis, Actinomyces oris, Fusobacterium nucleatum, Veillonella dispar, and Candida albicans) were exposed to DNase I (0.001 mg/mL, 0.002 mg/mL) or proteinase K (0.05 mg/mL, 0.1 mg/mL) for 1 h during biofilm formation. After 64 h, biofilms were harvested, quantified by culture analysis and visualized by image analysis using CLSM (confocal laser scanning microscopy). Statistical analysis was performed by ANOVA, followed by the Tukey test at a 5% significance level. The biofilm treatment with proteinase K induced a significant increase of Logs10 counts in S. mutans and a decrease in C. albicans, while biofilm thickness was reduced from 28.5 μm (control) to 9.07 μm (0.05 mg/mL) and 7.4 μm (0.1 mg/mL). Treatment with DNase I had no effect on the total bacterial growth within the biofilm. Targeting proteins of biofilms by proteinase K are promising adjunctive tool for biofilm control.

DNase inhibits early biofilm formation in Pseudomonas aeruginosa- or Staphylococcus aureus-induced empyema models

“…In our study, we found that DNase I had no effect on P. aeruginosa or S. aureus biofilm bacterial counts in vitro and in vivo, which is in agreement with results from previous studies (Kaplan et al, 2012;Xu et al, 2015). Karygianni et al reported that DNase affects the structural integrity and spatial distribution of biofilms, and that it has no effect on the total oral bacteria CFUs (Karygianni et al, 2021). This indicates that DNase acts as an antibiofilm agent, not as an antimicrobial; moreover, clinical experience shows that DNase needs to be combined with antibiotics in the treatment of pleural empyema.…”

“…Karygianni et al . reported that DNase affects the structural integrity and spatial distribution of biofilms, and that it has no effect on the total oral bacteria CFUs ( Karygianni et al., 2021 ). This indicates that DNase acts as an antibiofilm agent, not as an antimicrobial; moreover, clinical experience shows that DNase needs to be combined with antibiotics in the treatment of pleural empyema.…”

Ca2+ enhanced photosensitizer/DNase I nanocomposite mediated bacterial eradication through biofilm disruption and photothermal therapy

“…These results are consistent with the findings of other research groups on DNase I, which can indeed clear eDNA and achieve biofilm dispersion. [ 37,38 ] In comparison with the calcium phosphate mineralization group (CaP D ), we found that more than 50% of the eDNA was eradicated, which demonstrated that our calcium phosphate mineralization strategy could increase the activity of DNase I and enhance its eDNA cleavage function. It has also in the literature been reported that calcium cations could protect DNase I from proteolytic degradation [ 39,40 ] to maintain the long‐term DNase I release and bioactivity with Ca 2+ .…”

Typing of Candida spp. from Colonized COVID-19 Patients Reveal Virulent Genetic Backgrounds and Clonal Dispersion

“…The classification criteria were the OD values according to Stepanović et al (2007) [27]. To gain insight into the possible chemical nature of the molecules involved in adhesion, the biofilm formation assay was repeated with pretreatment with proteinase K (1 mg/mL in NaCl 100 mM/Tris 200 mM buffer, pH 7.5) at 56 • C for 2 h [28,29]. Differences between the biomass of biofilms with and without proteinase K treatment were determined, and a chi-squared test (p = 0.05) was used to determine differences between the two assays.…”