Strategies to analyse and control the extracellular polymeric substances of biofilm
Abstract
Abstract
Background and Aim: Until the discovery of biofilms in the 1970s, microorganisms were
considered to only exist in a free living or planktonic state. Biofilms occur when
microorganisms gather and aggregate on surfaces and produce extracellular polymeric
substances (EPS), which the microbial cells are embed in. Biofilms are involved in a wide
range of diseases and exhibit increased resistance to antimicrobial agents, due to numerous
and complex mechanisms, several of which depend upon EPS. EPS comprise of many
molecules and are produced primarily by the microorganisms but may also be acquired from
the surrounding environment. EPS provides a ‘scaffold’ for the biofilm and facilitates
attachment between cells and to the surface. EPS also affords physical and chemical
protection against external stresses. Given the importance of EPS to the biofilm, its
complexity and variations.
Aim: The aim of this research was to undertake a literature search to gain an overview of
the analytical and therapeutic approaches used with EPS.
Methods: Three databases were searched to retrieve articles related to analysing or
controlling EPS. Out of 1423 articles retrieved, 92 articles that discussed EPS analysis and
control were identified.
Conclusion: Overall, two groups of studies using approaches that analysed EPS and
sought to control EPS were identified. The first group employed specific targeting of known
EPS components and required prior knowledge of the targeted biofilm. The second group
was based on non-specific targeting, where the approach did not require previous
determination of the EPS, and all components were targeted. The latter was more useful in
exploring unknown EPS structures. However, for analysing EPS, most studies combined
different approaches to facilitate recognition and evaluation. It was clear from the research
that there was a need to improve analytical strategies in a manner that was affordable and
demanded limited expertise. Similarly, it was evident that strategies to control EPS had
undoubted potential as key methods for therapeutic intervention in managing biofilmassociated infections