A microfluidic system and confocal microscope for the molecular and mechanistic characterisation of microbial biofilms

Microbes, such as bacteria and fungi, are tiny organisms found in a wide range of environments on the earth, and within humans and animals. They have both positive and negative impacts; however, we are more often aware of their existence in relation to their negative effects such as on health (e.g. infectious disease) and in industry (e.g. corrosion of metals). Biofilms are the principal mode of microbial growth and consist of a clumping of cells glued together by a defensive mesh of self-produced molecules (the biofilm matrix). This form of growth provides protection from external factors such as dehydration but also from attack by other organisms, the host immune system and antimicrobial compounds. Biofilm formation causes problems in many industrial settings, such as in industrial water systems, shipping, agriculture, and the medical and process industries. This has an estimated economic cost of >$4tn globally and >£100bn in the UK. Biofilm growth has also had a major influence on the emergence of antimicrobial resistance, which currently represents one of the largest threats to humankind. They are a major cause of recurrent disease, they contribute significantly to the establishment of serious infections, and they cost the UK National Health Service (NHS) >£2bn to treat each year.

We seek to acquire a microfluidic system and a specialised (confocal) microscope, which will allow King's to study in great depth how biofilms form and how they can be eradicated. This characterisation down to the size scale of individual cells is critical for the fundamental understanding of these biological processes, as well as for new drug development. In particular, we will use this equipment extensively in our research efforts to understand the progression of oral and inflammatory diseases (e.g. tooth decay, gum disease, thrush, inflammatory bowel disease, Crohn's disease), and develop new ways of treating these diseases, as well as lung, nail, wound and hospital acquired infections. It is also possible that these types of study will result in the identification of molecules that can be developed into new biomaterials, and approaches that can be used to tackle biofilms in industrial settings. This instrument will permit us not only to develop our existing research at King's but will also be instrumental to develop new avenues of research, and for the training of the next generation of biomolecular scientists. In addition, a particular advantage of the instrument we seek to purchase, is that it allows us to not only study living biofilms while attached to the microscope, but they can also be removed so that even finer details can be investigated using other equipment which is also accessible within King's and at national facilities. This will enable us to bridge our studies across scales, from molecules to cells, and create a hub for biofilm research at King's.

Biofilms are groups of microorganisms that adhere to one another on a surface, through a self-produced matrix of extracellular polymeric substance, composed of proteins, carbohydrates, lipids, and DNA. This mesh provides protection against environmental pressures, host immune responses and antimicrobial agents. Biofilms cause problems in many industrial settings and have an economic cost of >$4tn globally and >£100bn in the UK. They are also a major cause of chronic infections and cost the NHS >£2bn to treat each year. As almost all bacteria and many fungi establish biofilms as a strategy for survival and persistence, understanding how they form is key to the development of new ways to combat biofouling, industrial corrosion, and antibacterial resistance; the latter being one of the largest current threats to humankind.

The aim of this application is to obtain the funding for a microfluidic system with a combined laser scanning confocal microscope (LSCM). This will allow research groups at King's to carry out detailed studies into how biofilms develop but also assess efficacy of new antimicrobial compounds and materials that disrupt biofilm growth and/or inhibit the initial stages of microbial colonisation. While our current focus of research centres around understanding the progression of microbial disease and the development of new anti-microbial treatments, our findings will feed into the development of new biomaterials and synthetic microbial communities, and strategies to tackle biofilms in industrial settings. This instrument will not only provide high-resolution in situ real time imaging of living biofilms but will also be employed to generate contained or fixed biofilms. These can then be studied with high resolution structural biology techniques such as cryo-electron microscopy/tomography (cryo-EM/ET) or solid/solution state nuclear magnetic resonance (NMR) spectroscopy and will form a bridge to other existing facilities at King's and nationally.