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Updated: Jan 6, 2026

Single-Molecule Dwell-Time Analysis of Restriction Endonuclease-Mediated DNA Cleavage
Published on: February 7, 2021
Diversity of type II restriction endonucleases that require two DNA recognition sites
Merlind Mucke1, Detlev H Kruger, Monika Reuter
1Institut für Virologie, Medizinische Fakultät (Charité) der Humboldt-Universität zu Berlin, D-10098 Berlin, Germany.
Abstract:
Orthodox Type IIP restriction endonucleases, which are commonly used in molecular biological work, recognize a single palindromic DNA recognition sequence and cleave within or near this sequence. Several new studies have reported on structural and biochemical peculiarities of restriction endonucleases that differ from the orthodox in that they require two copies of a particular DNA recognition sequence to cleave the DNA. These two sites requiring restriction endonucleases belong to different subtypes of Type II restriction endonucleases, namely Types IIE, IIF and IIS. We compare enzymes of these three types with regard to their DNA recognition and cleavage properties. The simultaneous recognition of two identical DNA sites by these restriction endonucleases ensures that single unmethylated recognition sites do not lead to chromosomal DNA cleavage, and might reflect evolutionary connections to other DNA processing proteins that specifically function with two sites.
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