Internship Report from the year 2014 in the subject Chemistry - Bio-chemistry, grade: 1,0, Free University of Berlin (Institut für Chemie und Biochemie), course: Methodenmodul Nukleinsäuren, language: English, abstract: The hammerhead ribozyme is a catalytic active RNA molecule that catalyzes the cleavage of RNA. This reaction is part of the in vivo self-cleavage mechanism that is observed in the rolling cycle replication mechanism of viroids. The chemically synthesized hammerhead ribozyme that is used in this experiment forms of two RNA strands that harbor the catalytic activity and a substrate RNA strand as shown in figure 1. In the presence of MgCl2, the ribozyme adopts its active conformation and cleaves substrate strand.In order to demonstrate the cleavage, the substrate strand is radioactively labeled with 32P at the 5 end by T4 polynucleotide kinase.