Not all enzymes that are assumed to require an RNA component in order to function do actually contain RNA. This surprising discovery was made during a project supported by the Austrian Science Fund FWF that focussed on the enzyme RNase P.
Contrary to accepted scientific theory, the project team from Vienna has long believed that certain forms of RNase P do not contain any RNA. They have now succeeded in proving their point through a series of sophisticated experiments, the results of which are being published today in the journal CELL.
Although ribozymes are not quite living fossils, these enzymes - which function only in the presence of RNA - hail from a long gone age when biochemical processes were still controlled by RNA molecules. It was only later that proteins came onto the molecular scene. RNase P, an enzyme that modifies transfer RNAs, is one such RNA enzyme (ribozyme). All previously characterised forms of this enzyme confirmed assumptions about their RNA component. Nevertheless, evidence has also been uncovered over the past 20 years that has cast doubt on the universality of this finding and indicated that this enzyme could be made up solely of proteins. The experts certainly had plenty to debate.