Microbial Biofilm and its Importance in Medicine

Overview

In natural environment, microbes grow mostly in the form of a biofilm. Biofilm is a structuredmicrobial community placed in an extracellular matrix and adhering to both inert and livesurfaces. Microbial cells growing as a biofilm have qualities fundamentally different from thoseof freely floating planctonic cells, in the first place they are extremely resistant to outerinfluences. The development and the architecture of the biofilm are described. Biofilms representa higher and more complex mode of microbial life and are an analogy of tissues of higherorganisms. They are characterised by 1. an effective homeostasis, 2. components of a primitivecirculatory system, 3. elements of cellular cooperation and specialization, and 4. a considerableway of protection against antimicrobial agents. The awareness of the biofilm penetrates onlyslowly into medical microbiology, even though it has been known that bacteria in the biofilmare as much as a thousand timesmore resistant to the effect of antibiotics than planctonic cells.Examples of chronic and persistent infections are given, in the pathogenesis of which asignificant role is played by the biofilm, growing both on the natural surface of tissues and onthe inert surface of different devices and prostheses inserted into the macrooganism. Possibleways to the therapeutic tampering with the biofilm are foreshadowed and the beneficial role ofthe biofilm in the protection of mucosal surfaces against pathogens is emphasized.

Key words:
biofilm - planctonic growth - extracellular matrix - adhesion to surfaces - quorumsensing- resistance to antibiotics - persistent infections - plastic devices - staphylococcal slime.