HORTICULTURE

Detailed explanation-1: -Klenow enzyme is a product of enzymatic breakdown of DNA polymerase I from E. coli.

Detailed explanation-2: -DNA Polymerase I possesses a 3´→5´ exonuclease activity or “proofreading” function, which lowers the error rate during DNA replication, and also contains a 5´→3´ exonuclease activity, which enables the enzyme to replace nucleotides in the growing strand of DNA by nick translation.

Detailed explanation-3: -DNA Polymerase I, Large (Klenow) Fragment is a proteolytic product of E. coli DNA Polymerase I which retains polymerization and 3’→ 5’ exonuclease activity, but has lost 5’→ 3’ exonuclease activity (1). Klenow retains the polymerization fidelity of the holoenzyme without degrading 5’ termini.

Detailed explanation-4: -The Klenow fragment is a proteolytic product of E. coli DNA polymerase I that retains polymerization and 3’ to 5’ exonuclease activity, but has lost 5’ to 3’ exonuclease activity.

Detailed explanation-5: -Klenow fragments are used to fill 5′ overhangs, sequence DNA, and synthesise dsDNA, probes and proteins. The Klenow fragment’s 3′ to 5′ exonuclease activity can also be undesirable sometimes.