Biochemistry 2280A Lecture Notes - Lecture 15: Reverse Transcriptase, Ap Endonuclease, Proofreading

• School: Western University
• Department: Biochemistry
• Course: Biochemistry 2280A
• Professor: Bonnie Mac Lachlan

Document Summary

Eukaryotes have a lot of dna, therefore multiple origins in order to speed up replication process. Sequence of rep. origin (typically rich in at pairs) is recognized by initiator proteins. Which pulls the double helix apart: rich in at b/c 2 h-bonds is easier to pull apart. After double helix is pulled apart replication fork forms, helices binds at replication fork the rest of the helix process consumes atp. Ssbp binds to unwound regions to prevent reannealing. Dna polymerase cannot start with nothing primase synthesizes a short rna primer in 5" > 3" direction. Primase, unlike dna polymerase, can start a new strand without 3"oh template upstream. Dna polymerase adds dntp"s in 5" > 3" direction, adding on to the 3" end. Mono nucleotides are added, and pyrophosphate is the by-product. By breaking the triphosphate on incoming dntp, energetically favourable. Substrate itself looks a lot like atp and provides energy brilliant.