The intrinsic resilience of biofilms to environmental conditions makes them an attractive platform for biocatalysis, bioremediation, agriculture, or consumer health. However, one of the main challenges in these areas is that beneficial bacteria are not necessarily good at biofilm formation.
Genetic engineering normally solves this problem, but scientists from the Birmingham university‘s School of Chemical Engineering have revealed a new method to increase efficiency in biocatalysis.
This screening used a strain of E. coli (MC4100) widely used in fundamental science to study genes and proteins and is known to be poor at forming biofilms compared to another E. coli strain, PHL644, an isogenic strain obtained through evolution that is a good biofilm former.
The chemicals that are most effective at promoting biofilm development were identified through this screening. Mildly cationic polymers were surpassed by hydrophobic polymers, while aromatic and heteroaromatic derivatives significantly outperformed the comparable aliphatic polymers.
Monitoring the biomass and biocatalytic activity of both strains incubated in the presence of these polymers revealed that MC4100 matched and even outperformed PHL644.
The findings indicated that the polymers precipitate in solution and act as coagulants, stimulating a natural process called flocculation that triggers bacteria to form biofilms.
Dr. Francisco Fernández Trillo from the School of Chemistry* said, “We explored a broad chemical space and identified the best-performing chemistries and polymers that increase the biocatalytic activity of E. coli, a workhorse in biotechnology. This has resulted in a small library of synthetic polymers that increase biofilm formation when used as simple additives to microbial culture. To the best of our knowledge, currently, there are no methods that provide this simplicity and versatility when promoting biofilms for beneficial bacteria.”
“These synthetic polymers may bypass the need to introduce the traits for biofilm formation through gene editing. It is costly, time-consuming, non-reversible, and requires a skilled person in microbiology to implement it. We believe this approach has an impact beyond biofilms for biocatalysis. A similar strategy could be employed to identify candidate polymers for other microorganisms such as probiotics or yeasts, and develop new applications in food science, agriculture, bioremediation or health.”