Infection protection

Scientists from the London Centre for Nanotechnology at UCL are using a novel nanomechanical approach to investigate the workings of vancomycin, an antibiotic that can be used to combat infections such as MRSA.

The researchers, led by Dr Rachel McKendry and Prof Gabriel Aeppli, developed ultra-sensitive probes that provided them with a new insight into how the antibiotic worked; research that could pave the way for the development of more effective new drugs.

Dr McKendry and her colleagues used micromachined cantilever arrays to examine the process that ordinarily takes place in the body when vancomycin binds itself to the surface of the bacteria.

They coated the cantilever array with mucopeptides from bacterial cell walls and found that as the antibiotic attaches itself, it generates a surface stress on the bacteria. That stress could then be detected by a tiny bending of the cantilevers. The researchers believe that it is this stress that contributes to the disruption of the cell walls and the breakdown of the bacteria.

‘The cell wall of these bugs is weakened by the antibiotic, ultimately killing the bacteria. Our research on cantilever sensors suggests that the cell wall is disrupted by a combination of local antibiotic-mucopeptide binding and the spatial mechanical connectivity of these events. Investigating both these binding and mechanical influences on the structure of the cells that could lead to the development of more powerful and effective antibiotics in future,' said Dr McKendry.

'This work demonstrates the effectiveness of silicon-based cantilevers for drug screening applications,' added Prof Gabriel Aeppli, director of the LCN.

The research was funded by the EPSRC (Speculative Engineering Programme), the IRC in Nanotechnology (Cambridge, UCL and Bristol), the Royal Society and the BBSRC.