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Lecture 16. Nucleic Acid Chemistry. Hydrolysis of RNA. Occurs under alkaline conditions. Hydrolysis of RNA. Nucleic Acid Chemistry. Denaturation (increase T). RNA-RNA>RNA-DNA RNA-DNA>DNA-DNA. Nucleotides Absorb UV Light. Base stacking decreases absorption Hypochromic effect.
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Lecture 16 Nucleic Acid Chemistry
Hydrolysis of RNA • Occurs under alkaline conditions
Nucleic Acid Chemistry Denaturation (increase T) RNA-RNA>RNA-DNA RNA-DNA>DNA-DNA
Nucleotides Absorb UV Light • Base stacking decreases absorption • Hypochromic effect
DNA photolyase Native DNA uv light Pyrimidine dimer DNA photolyase binds ( Light (>300nm) Light used to correct dimer Enzyme releases repaired DNA
DNA Sequencing • Mid 1970s • Alan Maxam and Walter Gilbert • Chemical cleavage method • Fred Sanger • Chain-terminator method • Dideoxynucleotides
Maxam Gilbert DNA Sequencing 1. Cleave DNA strand at specific nucleotides -e.g. A only 2. Separate fragments according to size by electrophoresis
Sanger Method • Simpler and more widely used • Uses DNA replication by DNA polymerase • All DNA polymerases • Require primer + template • Synthesize 53