( ( ribozyme ( structure-function ( and ( RNA-protein interactions ) ) ) ) . )
(ROOT (S (VP (VB ribozyme) (NP (JJ structure-function) (CC and) (JJ RNA-protein) (NNS interactions))) (. .)))
ribozyme structure-function and RNA-protein interactions.
(ROOT (S (NP (NP (DT The) (NN discovery)) (PP (IN of) (NP (NNS ribozymes)))) (VP (VBD nullified) (NP (DT the) (NN idea)) (SBAR (IN that) (S (NP (DT all) (JJ biological) (NNS catalysts)) (VP (VBP are) (NP (NNS proteins)))))) (. .)))