Australian physicists have developed a way to use waves to manipulate the growth of bacteria biofilms – one of the most abundant forms of life on Earth.
Hua Xia and colleagues from the Australian National University (ANU) found the growth of biofilms in a liquid could be promoted or retarded by different regimes of wave motion set up in the liquid.
They say this could help improve how we deal with chronic infections and antibiotic resistance, as well as the food we eat and the clothes we wear.
Xia says scientists have been trying to understand and control biofilms for decades.
“Formation of biofilm starts when the bacteria attach to the right type of surface. They’re formed by the bacteria to create a safe environment, to shield themselves from dangers,” she says.
“For example, dental plaque is a common example of a biofilm. Outside our bodies, pond scum is another example. Biofilms thrive on moist or wet surfaces.
“But they’re not necessarily harmful to people. In wastewater treatment plants and agricultural technology, we utilise the ability of bacteria to form biofilms.”
The ANU team had previously shown that surface waves drive flow currents within a liquid. They used these findings to develop the new approach to controlling biofilm formation on the liquid-solid interface.
Using fluorescent dyes to visualise the currents, they found that turbulent motion discouraged the attachment of bacteria and biofilm formation. In contrast, stable flow regimes could encourage biofilms to grow into various patterns.
“We believe this is because stable flow patterns generate localised transport routes that connect the bottom of the container to the surface and deliver oxygen,” Xia says.
The wave action is the strongest at the liquid-air interface, where some microorganisms form a compound called bacterial cellulose.
This wave-based approach could help engineer new forms of bacterial cellulose, which is used for everything from textiles and cosmetics to food products, as well as in the medical field for tissue engineering scaffolding, drug delivery and wound dressing.
“We’re now focused on creating various cellulose forms and controlling their properties, such as its water-holding capacity or mechanical strength,” Xia says.
The research is described in a paper in the journal Science Advances.
Read science facts, not fiction...
There’s never been a more important time to explain the facts, cherish evidence-based knowledge and to showcase the latest scientific, technological and engineering breakthroughs. Cosmos is published by The Royal Institution of Australia, a charity dedicated to connecting people with the world of science. Financial contributions, however big or small, help us provide access to trusted science information at a time when the world needs it most. Please support us by making a donation or purchasing a subscription today.