BIOL 4246 Chapter : 6 22 12
Document Summary
Regulation of transcription in terms of ancillary proteins. These transcriptional anciallary proteins can be activaros or repressors. First would increase transcription and the other would decrease it. The lac operon is the paradigm of this process. Series of 3 genes, laczya which are expressed and regulated together. To have high expression of the operon you need lactose present and no better substrate present. Laci binds o1, o3, o3 to repress the operson. Glucose phosphorylated as it comes in. specific enzymes for glucose that will allow this to happen. Enziia glucose is the signaler that tells the cell whether glucose is present or not. When glucose is present and being transported, a significant portion of the enzyme is found in the non-phosphorylated form. Inducer exclusion- when glucose is being transported enziia in non-pi form will bind to non-pts systems and inhibit them: lac permease uses the proton gradient and symport to get lactose into the cell.
