| Primary Identifier | IPR004603 | Type | Family |
| Short Name | DNA_mismatch_endonuc_vsr |
| description | This entry represents VSR (very short patch repair) endonucleases occurring in a variety of bacteria and some archaeal species, including DNA mismatch endonuclease Vsr from Escherichia coli. VSR recognises a TG mismatched base pair, generated after spontaneous deamination of methylated cytosines, and cleaves the phosphate backbone on the 5' side of the thymine []. GT mismatches can lead to C-to-T transition mutations if not repaired. VSR repairs the mismatches in favour of the G-containing strand. In Escherichia coli, this endonuclease nicks double-stranded DNA within the sequence CT(AT)GN or NT(AT)GG next to the thymidine residue, which is mismatched to 2'-deoxyguanosine []. The incision is mismatch-dependent and strand specific. The structure of VSR is similar to the core structure of restriction endonucleases, which have a 3-layer alpha/beta/alpha topology []. |
