Nuclease S1 from Aspergillus oryzae is widely used in molecular biology for its ability to specifically digest single-stranded DNA and RNA. It is commonly employed in the mapping and analysis of nucleic acid structures, such as identifying single-stranded regions in DNA or RNA hybrids. This enzyme is also utilized in the removal of single-stranded overhangs from DNA fragments, facilitating the preparation of blunt-ended DNA for cloning or ligation. Additionally, Nuclease S1 is applied in the study of RNA secondary structures and in the detection of mismatches in DNA hybrids. Its precision in targeting single-stranded nucleic acids makes it a valuable tool in genetic research and biotechnology applications.