The existence of so-called biofilms, created around bacteria and other single microorganisms including algae, are believed to be an important self-defence mechanism in protecting the colony from attack. In the case of bacterial colonisation, protection would be afforded against the body’s immune system or antibiotics. Biofilms are well recognised, but until recently it was thought that these films took the form of an amorphous extracellular matrix, making a sort of “goop” around the bacterial infection. Now, researchers from the University of York have established that there may be a bit more to it, having identified a degree of apparent organisation in the biofilm structure.
Bacteria such as Staphylococcus aureus, the ‘superbug’ behind MRSA, can be a major problem for patients who have a medical implant, such as a replacement heart valve or pacemaker.
The University of York has chosen to issue a post on its news pages about the work being undertaken in its Department of Biology on the subject of bacterial biofilms.
According to the news release, bacteria are able to form colonies on the implanted device, which can lead to wider infections such as endocarditis, a bacterial infection of the heart. Biofilms help the bacteria within the colony to avoid attack from the immune system and antibiotics.
Understanding these biofilms is thought to be important in the prevention of these troublesome and dangerous infections which often require the removal of implanted medical devices with all the attendant risks.
Scientists in the Department of Biology at the University of York claim to have shed new light on how “biofilm” structures are formed.
The team from the University of York, led by Professor Jennifer Potts, included British Heart Foundation-funded PhD student Dominika Gruszka. They found that the bacteria release long, thin protein chains to connect with other bacteria or mesh with other bacterial products. The chains have a highly unusual repetitive structure which could not have been predicted and provides important clues to how they might work.
Both S. aureus and S. epidermidis demonstrate the formation of these proteinaceous structures.
Professor Potts, a BHF Senior Research Fellow, said: “This discovery provides an important step forward in understanding how biofilms form. It should help in the development of new ways of preventing infection of cardiac devices by these bacteria.”
Dr Hélène Wilson, Research Advisor at the British Heart Foundation, which co-funded the study, said:
“These clusters of bacteria on implanted devices can be a problem for heart patients because they are very difficult to treat with antibiotics. Often the only way to tackle the infection is to remove the affected device, which can be a difficult and invasive process and lead to further complications.
“This discovery is an important step towards improving our understanding of how these biofilms are structured, which could help lead to new treatments or new ways to prevent them forming.”
Source: The research, which also involved scientists at Trinity College and the Universities of Cambridge, Huddersfield, Leeds, is published in PNAS Online Early Edition.