Biology 1202B Lecture Notes - Lecture 11: Exonuclease, Nucleosome, Primase
8 Feb 2016
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Biology 1202b: lecture 11 dna replication ii. It has not escaped our notice that the specific paring we have postulated immediately suggests a possible copying mechanism for the genetic material . New strand assembled 5" to 3" (oh-) Hydrolysis of 2 phosphates: phosphodiester linkage elongates chain. Structure is able to hold together for very long time under some stress, but is easily able to be pulled apart using enzymes in order to replicate. Palm conserved between species: finger and thumb differ. Clamp keeps polymerase tethered to template (prevents polymerase from falling off: increases efficiency. Origin of replication determines the start point for replication: just one origin for circular chromosomes. Single-stranded binding proteins stabilize dna, preventing the 2 strand from reforming into a double-stranded piece of dna. Primase synthesizes a short rna primer to initiate a new dna strand. Polymerase extends the new dna from the primer. Topoisomerase prevents super coiling by nicking the backbone.
