DNA Replication, Repair & Recombination

Semi-Conservative Replication

Discontinuous

Replication

on Lagging Strand

(Okazaki Fragments)

Continuous

Replication

on Leading Strand

Leading and Lagging Strand DNA Replication

Leading Strand

Lagging Strand

DNA Replication

DNA Replication

DNA Replication

DNA Polymerase I

DNA Polymerase I Structure

DNA Replication Proteins

Replication Fork

Beta Clamp

Top View Side View

DNA

Chemical Mechanism of Chain Elongation

Leading / Lagging Strand Replication

DNA Topoisomers

Topoisomerase Action

Topoisomers/Topoisomerases

L = T+W

L = Linking Number

T = Twists

W = Writhes

Polymerase Chain Reaction

Polymerase Chain Reaction

Polymerase Chain Reaction

Polymerase Chain Reaction

Polymerase Chain Reaction

DNA Proof-reading

Prokaryotic vs Eukaryotic DNA Replication • Introduction

Chromosomes With Telomeres Telomeres

Linear DNA Replication

Telomerase Action

Telomerase Action

Nucleotide Excision Repair

Bulky DNA Adduct

Nucleotide Excision Repair

Nucleotide Excision Repair

Nucleotide Excision Repair • Thymine Dimers

Nucleotide Excision Repair

Thymine Dimer

Repair

Partial Strand

Removal

Base Excision Repair

Cytosine Deamination

Cytosine Uracil

Base Excision Repair

Flipping out of

base from helix

Base Excision Repair

Uracil-N-Glycosylase Catalysis

Excision of Base

DNA Mismatch Repair

Mismatch

DNA Mismatch Repair

Unmethylated,

recognizable

Methylated,

unrecognizable

Measuring Mutation

Ames Test

DNA Recombination

DNA Recombination • Strand Invasion

Structure • Introduction

DNA Recombination • Holliday Junction

Recombination/Repair

RecA Recombination Repair in E. coli