In Vitro and In Vivo Antibiofilm Potential of Eicosane Against Candida albicans.

Candida albicans is the most prevalent fungus in humans, producing infections ranging from mucosal to systemic. C. albicans colonizes mucosal surfaces asymptomatically as commensal, but, if the host environment is disrupted, or if the host immune system is compromised, C. albicans can multiply and infect almost all places in the host. The present study was aimed to identify a promising antibiofilm agent against Candida albicans biofilm. Through the molecular docking approach, it was identified that Eicosane was the top hit among the alkanes screened. Furthermore, in vitro analysis revealed that Eicosane at 100 µg/mL was able to inhibit 60% of C. albicans biofilm without inhibiting the growth. Moreover, light microscopic investigation unveiled the significant reduction in the adhesion and colonization of yeast cells to the matrix on Eicosane-treated samples. The CLSM images showing a reduction in biomass and thickness of C. albicans biofilm in the presence of Eicosane were validated using COMSTAT. The results were well corroborated with SEM micrograph in which a pellucid gap between the cells was observed and colonization was considerably reduced. Further from qPCR analysis, the genes responsible for biofilm formation and hyphal growth were found to be downregulated in the presence of Eicosane. Similarly, Eicosane at BIC was able to significantly inhibit the adhesion and colonization of yeast cells on the chorion of the zebrafish embryos. Moreover, the binding ability of Eicosane to ALS3 was revealed through docking and molecular dynamics (MD) simulation studies.

Evaluation of antibiofilm potential of four-domain α-amylase from Streptomyces griseus against exopolysaccharides (EPS) of bacterial pathogens using Danio rerio.

Biofilm formation is a major issue in healthcare settings as 75% of nosocomial infection arises due to biofilm residing bacteria. Exopolysaccharides (EPS), a key component of the biofilm matrix, contribute to the persistence of cells in a complex milieu and defends greatly from exogenous stress and demolition. It has been shown to be vital for biofilm scaffold and pathogenic features. The present study was aimed to investigate the effectiveness of four domain-containing α-amylase from Streptomyces griseus (SGAmy) in disrupting the EPS of multidrug-resistant bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. In vitro analysis of preformed biofilm unveiled the antibiofilm efficacy of SGAmy against MRSA (85%, p < 0.05) and P. aeruginosa (82%, p < 0.05). The total carbohydrate content in the EPS matrix of MRSA and P. aeruginosa was significantly reduced to 71.75% (p < 0.01) and 74.09% (p < 0.01), respectively. The findings inferred from in vitro analysis were further corroborated through in vivo studies using an experimental model organism, Danio rerio. Remarkably, the survival rate was extended to 88.8% (p < 0.05) and 74.2% (p < 0.05) in MRSA and P. aeruginosa infected fishes, respectively. An examination of gills, kidneys, and intestines of D. rerio organs depicted the reduced level of microbial colonization in SGAmy-treated cohorts and these findings were congruent with bacterial enumeration results.

Suppression of Thiol-Dependent Antioxidant System and Stress Response in Methicillin-Resistant Staphylococcus aureus by Docosanol: Explication Through Proteome Investigation.

The present study was aimed to investigate the effect of docosanol on the protein expression profile of methicillin-resistant Staphylococcus aureus (MRSA). Thus, two-dimensional gel electrophoresis coupled with MALDI-TOF MS technique was utilized to identify the differentially regulated proteins in the presence of docosanol. A total of 947 protein spots were identified from the intracellular proteome of both control and docosanol treated samples among which 40 spots were differentially regulated with a fold change greater than 1.0. Prominently, the thiol-dependent antioxidant system and stress response proteins are downregulated in MRSA, which are critical for survival during oxidative stress. In particular, docosanol downregulated the expression of Tpx, AhpC, BshC, BrxA, and YceI with a fold change of 1.4 (p = 0.02), 1.4 (p = 0.01), 1.6 (p = 0.002), 4.9 (p = 0.02), and 1.4 (p = 0.02), respectively. In addition, docosanol reduced the expression of proteins involved in purine metabolic pathways, biofilm growth cycle, and virulence factor production. Altogether, these findings suggest that docosanol could efficiently target the antioxidant pathway by reducing the expression of bacillithiol and stress-associated proteins.