A deeper look into the apparent self-defense mechanisms of these bacteriophage-resistant bacteria revealed their secret weapon: a group of enzymes called restriction endonucleases, or restriction ...

but they did not identify and isolate restriction enzymes until the late 1960s. 3 In 1970, Hamilton Smith and Kent Wilcox from Johns Hopkins University discovered “endonuclease R” (later named HindII) ...

The enzyme-specific sequence allows the ligation of the adapters to the resulting restriction fragments (green) without restoring the original restriction sites. In this way, ligated adapters ...