A ribozyme named for the resemblance of early secondary structure diagrams to a hammerhead shark
Ribozymes are RNA enzymes. This means they may serve as a genetic material as well as a biological catalyst. Hammerhead ribozyme is an example of a ribozyme. As a catalyst, the hammerhead ribozyme can speed up reversible cleavage and joining reactions at a particular site within the RNA molecule. However, it requires the presence of a metal ion to be active catalytically. The name hammerhead is due to the resemblance of early secondary structure diagrams to a hammerhead shark.1 Hammerhead ribozymes are first discovered in RNA plant pathogens: viral satellite and viroids.2 Later, further research found that ribozymes are widespread, occurring from bacterial to eukaryal genomes.3
1 Forster, A. C. & Symons, R. H. (1987). "Self-cleavage of plus and minus RNAs of a virusoid and a structural model for the active sites". Cell 49 (2): 211–220.
2 Prody, G. A., Bakos, J. T., Buzayan, J. M., Schneider, I. R., & Bruening, G. (1986). "Autolytic Processing of Dimeric Plant Virus Satellite RNA". Science 231 (4745): 1577–1580.
3 De la Peña, M. & García-Robles, I. (2010). "Ubiquitous presence of the hammerhead ribozyme motif along the tree of life". RNA 16 (10): 1943–1950.