Does surface wettability influence bacterial adhesion?
Rieder, A. / Ladnorg, T. / Wöll, C. / Obst, U. / Fischer, R. / Schwartz, T. (2011)
Eurobiofilms 2011, Kopenhagen, Dänemark, 6.-8. Juli, 2011
Rieder, A. / Ladnorg, T. / Wöll, C. / Obst, U. / Fischer, R. / Schwartz, T. (2011): „Does surface wettability influence bacterial adhesion?“. In: Eurobiofilms 2011, Kopenhagen, Dänemark, 6.-8. Juli, 2011
Microorganisms can establish biofilms on a great variety of surfaces which is considered to be a major problem especially in medical fields, food industry and biotechnology. However, the characteristics of a material and its corresponding surface properties affect the biocompatibility and bacterial adhesion.
In this study recombinant fusion hydrophobins were tested for surface modification to change surface hydrophobicity and influence biofilm formation. Hydrophobins are non-toxic and non-immunogenic fungal proteins which self-assemble on different surfaces into extremely stable monolayers in an amphiphilic manner.
The adsorption behaviour of the recombinant fusion hydrophobins was analyzed and protocols for surface modification were developed. The characterization of the hydrophobin coatings with respect to hydrophobicity and homogeneity indicated that the self-assembly process of the hydrophobins depended on temperature and time.
Single bacterial strains as well as natural bacterial communities were used to analyse the impact of hydrophobin modified surfaces on different stages of biofilm formation. Apart from conventional plating experiments, fluorescence microscopy and molecular-biological methods such as denaturing gradient gel electrophoresis were applied to determine differences in the biofilm growth.
The results demonstrated that the change of surface hydrophobicity and the fusion hydrophobins itself did not affect biofilm formation. Due to their self-assembly properties, fusion hydrophobins can be used for effective large-scale surface coating of medical and industrial relevant materials in monolayer manner. To stimulate the effect on biofilm formation the hydrophobins can subsequently be functionalized with bioactive molecules like antimicrobial peptides to influence the bacterial adhesion.