BIOB11H3 Lecture Notes - Lecture 13: Dna Polymerase Iii Holoenzyme, Dna Polymerase I, Dna Replication
Document Summary
Biob11-l13: dna replication ii enzymology, origins, organization & licensing: kornberg (1950s) Purified e. coli dna polymerase dna + dntps (datp, dctp*, dgtp, dttp) dna polymer* Left column = no replication (no 3(cid:859)oh group for dna pol to begin replicaiton) Right column = replication (3(cid:859) oh group for dna pol) Place down rna primer on lagging strand for replication to occur. Helicase: hexamer molecule made up by 6 same proteins. Eye / bubbles: the bi-directional expansion of unwound dna. Each fork one leading & one lagging strand. Problem: the polymerases that replicate the leading & lagging strands only work 5(cid:859) to 3(cid:859), but they are part of replisome complex that move in the same direction. The lagging strand template will form a loop. Release of loop, action of primosome (unwind + primer) *trombone model lagging strand template changes size, similar to that of a trombone.
