Polymerase Active Sites Quiz

3

The reactive OH at the end of the DNA primer strand is on the ____ (number) carbon

Arginine

Forms hydrogen bonds to BOTH the reactive nucleotide's base at the 3prime end of the primer strand AND to the ring-closing oxygen of the incoming dNTP's ribose

base-pairing

Selection of the correct dNTP during each step in replication directly depends on ________ to the template

Glutamate

Blocks entry of NTPs into T7 DNA polymerase's active site

Glutamine

Forms a hydrogen bond to the template base complementary to the 3'-end primer strand deoxyribonucleotide's base

5

The reactive alpha phosphate is structurally bound to the ___ (number) prime carbon of the dNTP

2

Deoxyribose lacks an oxygen at the _____ (number) prime carbon

Pyrophosphate

The inorganic byproduct of the polymerase reaction is _____

3prime-5prime exonuclease

Increases the fidelity of replication by 1000X fold

Aspartate

Positions the two catalytic Mg++ ions in the active site of all DNA polymerases

1

Nitrogenous bases are covalently attached to the ____ (number) prime carbon of nucleotides

Histidine

Requires a 2prime-OH to stably incorporate NTPs within the active site of an RNA polymerase

Glycine

Makes room to accommodate the 2prime-OH of incoming NTPs in an RNA polymerase