We developed a new type of oligonucleotide-based catalysts which can be called DNAzyme, ribozyme, or aptazyme. They were in vitro selected from a random sequence library of DNA or RNA for binding hemin. The selected oligonucleotides exhibited peroxidase activity by forming a complex with hemin. In addition, an azobenzene-containing oligonucleotide which bound to hemin was also selected. The binding and the catalytic activity was controlled by photo-irradiation. Subsequently, hybridized biocatalysts with synthetic polymers were synthesized. Polyethylene glycol-conjugated antibodies and oligonucleotides were synthesized and it was demonstrated that they were active in organic media. A photo-responsive polymer was also conjugated with an enzyme and its catalytic activity was controlled in organic media.