   3.1.11.2 | Exonucleolytic cleavage in the 3'- to 5'- direction to yield nucleoside 5'-phosphates |
XthA exonuclease converts the blunt ends of double-stranded DNA to 5' protruding ends in the process of in vivo cloning. After the insert and the vector DNA fragments are introduced into the Escherichia coli cell, XthA resects the ends of the DNA fragments from the 3'-to-5' direction, producing 5' overhanging ends. As the ends of insert and vector DNAs have mutually complementary sequences, the 5' overhanging ends of the insert and the vector DNA fragments hybridize to each other as cohesive ends. In addition, the gaps are filled by DNA polymerases and the nicks are repaired by DNA ligases |
750978 |
