Endonuclease that can use single-stranded RNA and DNA as substrates (PubMed:23620482). In contradiction with PubMed:23620482, cannot hydrolyze single-stranded DNA and does not cleave mismatches (PubMed:17651368). Endonucleolytic cleavage to 5'-phosphomononucleotide and 5'-phosphooligonucleotide end-products. Binds 3 divalent metal cations. Optimum pH is 8 with RNA and ssDNA as substrates. Monomer. Belongs to the nuclease type I family.