The Klenow fragment is a large protein fragment produced when DNA polymerase I from E. coli is enzymatically cleaved by the protease subtilisin. First reported in 1970, it retains the 5'-3' polymerase activity and the 3’ → 5’ exonuclease activity for removal of precoding nucleotides and proofreading, but loses its 5' → 3' exonuclease activity.
The other smaller fragment formed when DNA polymerase I from E. coli is cleaved by subtilisin retains the 5'-3' exonuclease activity but does not have the other two activities exhibited by the Klenow fragment (i.e. 5'-> 3' polymerase activity, and 3'->5' exonuclease activity).
Read more about Klenow Fragment: Research, The Exo- Klenow Fragment
Famous quotes containing the word fragment:
“Every woman is like a time zone. She is a nocturnal fragment of your journey. She brings you unflaggingly closer to the next night.”
—Jean Baudrillard (b. 1929)