Ch 14: Steps for DNA Replication in Prokaryotes

1

DNA unwinds at origin of replication

2

Helicase opens up replication forks, extended bidirectionally

3

single-strand binding proteins coats DNA around replication fork, prevents rewinding of DNA

4

Topoisomerase binds ahead of replication forks to prevent supercoiling

5

primase synthesizes RNA primers complementary to DNA template strand

6

DNA polymerase III (w/ sliding clamp) adds nucleotides to 3’ -OH end of RNA primer

7

elongation of both the lagging and the leading strand continues bidirectionally

8

RNA primers removed by exonuclease activity

9

DNA pol I fills gaps left from primer excision by adding DNA bases

10

gap between the 2 DNA Okazaki fragments is sealed by DNA ligase, helps formation of phosphodiester bonds