Ionic liquids can be designed to control protein activity, say Australian researchers.

Adam McCluskey at the University of Newcastle, New South Wales, Australia, and colleagues have found some of the most potent inhibitors of dynamin, an enzyme with a range of biochemical roles.

'Almost weekly there are reports of dynamin mediated biological effects, but as yet there are few chemical tools for studying it, and even fewer agents that might have an effect on diseases related to abnormal levels of dynamin expression or mutations,' said McCluskey.

McCluskey's team made their ionic liquids by modifying cantharidin, a compound secreted by the emerald green beetle known as the Spanish fly. Cantharidin is purported to be an aphrodisiac, although even relatively small doses can be fatal to humans.

'We can tune room temperature ionic liquids (RTILs) to interact with proteins benignly via solvation and stabilisation, or as inhibitors,' said McCluskey.  Although the team had been investigating the solvation of proteins, they were 'delighted' to discover the inhibitory effects.

'The serendipitous outcome was new inhibitors of dynamin. Given the increasing relevance of dynamin in human physiological conditions, for example Charcot-Marie-Tooth, a common heredity disorder, this is a significant advance,' explained McCluskey.

Nick Gathergood, a researcher in ionic liquids at Dublin City University, Ireland, said the discovery of therapeutic properties of these ionic liquids is a significant development. 'The work illustrates an exciting interface of ionic liquid research with medicinal chemistry. These novel materials have great potential,' he added.

However, there is still plenty of work to be done. 'The lack of predictability in the assembly of a cation and anion in the generation of an RTIL is a major hurdle yet to be overcome,' said McCluskey.  He also cautioned that 'as these RTILs gain mainstream acceptance we must examine their potential utility and potential impact on biological systems'.

Colin Batchelor