We have recently introduced novel methods for constructing a wide variety of ligand-binding receptors and fluorescent biosensors based on a framework of ribonucleopeptide (RNP) composed of an RNA subunit and a peptide subunit. The modular RNP complex would be potentially applicable to the fabrication of the artificial enzyme because each subunit could be functionalized separately. In this study, we focused on the material conversion process in the photosynthesis and aimed at the development of the artificial photodriven enzymes based on the RNP complex. The strict control of the configuration and orientation of functionalized motifs is needed for the rational design of the RNP-based enzyme. To clarify the relationship between the structure and the function of RNP receptor, secondary structure of the ATP-binding RNP receptor was investigated. As a result, the model for the ATP-binding RNP complex could be proposed based on the chemical structure analyses. © Springer 2010.