BIOL2202 Lecture Notes - Lecture 6: Autotroph, Joiner, Collinearity
Document Summary
Recall how replication fork/helicase shutters when reaching a thymine dimer in dna. Sos response in e. coli: sos response activated when dna is heavily damaged. Dna polymerase v (5) continuous to replicate the damaged dna. The replication is full of incorrect bases, but the polymerase v does not care. Dna recombination mechanisms: recombination of homologous chromosomes involve enzymes used in dna replication and repair. This exchange connects both chromosomes into one unit (image e) The connection is at the bridge formed by both strands crossing over: dna ligase fixes the nick originally made, one chromosome twists around in the other direction. The alleles on both chromosomes are facing opposite directions. From the connection bridge, we can see 4 segments of dna. Garrod came up with the idea what one gene was equivalent to one metabolic block: garrod was observing inborn errors of metabolism.
