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Discovery In contrast to in vitro selection methods, which have aided in identifying several classes of catalytic RNA motifs, the twister ribozyme was discovered by a bioinformatics approach.[1] Researchers were inspired to name the newly found twister motif due to its resemblance to the hieroglyoh 'twisted flax'.

Structure The basic structure of the twister ribozyme, from Oryza sativa, was crystallographically determined at atomic resolution in 2014.[2] The active site of the twister ribozyme is centered in a double-pseudoknot, facilitating a compact fold structure.

Catalytic Mechanism Similar to other nucleolytic ribozymes, the twister ribozyme selectively cleaves phopshodiester bonds, through an SN2-related mechanism, into a 2',3'-cyclic phosphate and 5' hydroxyl product.[1] So far, it is known that rate of reaction of twister is affected by pH and divalent metals. Metals increase the rate of reaction, however, they most likely play a structural role since the rate of the reaction seemed to be same in different divalent metals.[1] A hill shaped pH-rate profile indicates that there is probably a general acid-general base catalysis involved like the hammerhead ribozyme. However, conclusive evidence for acid-base catalysis is still being pursued.

Prevalence in Nature The twister ribozyme motif is relatively common in nature with 2,700 examples observed across bacteria, fungi, plants, and animals.[2] Similarly to hammerhead ribozymes, some eukaryotes contain large numbers of twister ribozymes. In the most extreme known example, there are 1051 predicted twister ribozymes in Schistosoma mansoni, an organism that also contains many hammerhead ribozymes. In bacteria, twister ribozymes are near to gene classes that are also commonly associated with bacterial hammerhead ribozymes.