Rapid enzyme screening
A fast, efficient screening method that could test vast numbers of enzymes for specific applications has been discovered by researchers in the UK, bringing made to order enzymes a step closer.
The screening method, developed by Nicholas Turner and co-workers at the University of Edinburgh, works by treating enzyme mutants with indole. If the enzyme is active, indigo is produced in the reaction. A quick visual screen identifies the active enzymes, which can then be screened against new substrates.
A rapid visual enzyme screen using the indole to indigo colour change
The group used mutants of the enzyme P450cam, a member of the cytochrome P450 family of enzymes. These enzymes can catalyse the oxidation of non-activated carbons; reactions that are difficult to perform in a lab.
In nature the enzymes convert toxic compounds into less harmful substances. This makes selectivity unnecessary, and it becomes desirable for there to be no discrimination between substrates. Turner's aim is to find enzymes with higher levels of selectivity, making fast screening vital.
A Çelik, R E Speight and N Turner, Chem. Commun., 2005, 3652 (DOI: 10.1039/b506156c)