Endonuclease mostly active on RNA and ssDNA, and to a lower extent, on dsDNA (PubMed:22506810, PubMed:23620482). Can cleave mismatch regions in heteroduplex DNA containing single base pair mismatches or insertion/deletion bases (PubMed:22506810). In contradiction with PubMed:22506810, 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 (PubMed:23620482, Ref.7, PubMed:25157844). Use Mn(2+) and Ca(2+) as cofactors with ssDNA as substrate in basic conditions (pH 8) (PubMed:23620482). Can use Zn(2+) with lower efficiency with dsDNA and ssDNA as substrates in acidic conditions (pH 5.5) (PubMed:23620482, Ref.7, PubMed:25157844). ssDNase activity is inhibited by the divalent cation chelator EDTA and the reducing agent DTT (PubMed:22506810). Divalent metal ions (e.g. Ca(2+), Mg(2+) and Zn(2+)) and DTT represses RNase activity (PubMed:22506810, PubMed:25157844). RNase activity is enhanced by EDTA (PubMed:22506810). Also repressed by vanadate (VO(4)(3-)) and phosphate (PO(4)(3-)) by occupying the active site (PubMed:25157844). kcat is 19171 min(-1) with ssDNA as substrate (at pH 7.0 and 37 degrees Celsius). Optimum pH is 7-8 with ssDNA as substrate (PubMed:22506810, PubMed:23620482). Optimum pH is 6 with RNA as substrate (PubMed:22506810). Optimum pH is 5.5 with dsDNA as substrate (PubMed:23620482). Optimum temperature is 70 degrees Celsius. Low activity at temperatures below 30 degrees Celsius. Above 70 degrees Celsius, the catalytic activity declines. Monomer. N-glycosylation is required for enzymatic stability and activity. Can be applied to high-throughput detection of single base mutation. Belongs to the nuclease type I family.