BIO230H1 Lecture Notes - Lecture 3: Riboswitch, Cytosol, Purine
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BIO230H1 Full Course Notes
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The notes only make sense when read alongside the slides. If something"s on the slides, it probably isn"t in my notes. Dna cis elements: regulatory elements (2 kinds) one type of gene regulatory protein turns repressors on the other type turns repressors off. The only time you turn the lactose on is if you are all out of glucose because glucose is the preferred energy source for bacteria. Negative regulation: competition between rna polymerase and repressor protein for promoter binder. Positive regulation: activator protein recruits rna polymerase to the promoter to activate transcription. Lac repressor is a tetramer (four identical subunits) and can bind two operators simultaneously. Gene regulatory switch that controls lifestyle of bl (molecule that infects bacteria) lands on a bacterial cell and injects its dna into bacterial cell. Two proteins repress each others synthesis (a simple transitional circuit) one protein affects expression of other protein. But if cell is compromised, bl chooses lifestyle of lytic.
