MCDB 427 Lecture Notes - Lecture 9: Lac Repressor, Autoregulation, London Academy Of Music And Dramatic Art

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When glucose is high, cell uses it to make atp (thus low amp) If glucose levels go down, there will be low atp but more amp. Lactose won"t be used until you run out of glucose. The example we"ll use deals with the lac operon. What"s happening is that the cells are first using glucose and then it switches to. Positive is mediated by camp and cap (catabolite activator protein) This was recognized because of the behavior of e. coli cells that were in media that contained both glucose and lactose. We get dioxyate growth (this is shown in the curve) In positive control, when a regulatory protein binds to a regulatory sequence in front of a set of genes in an operon, there is an increase in transcription lactose. This tells us that it prefers glucose over lactose (along with many other sugars) There must be something in the cell that senses the levels of glucose.