BIO206H5 Lecture 17: BIO206 Lecture 17 Chapter 8.pdf
Document Summary
Lac operon: involved in metabolism of sugar (lactose) lac i, lac z, lacy & laca = genes that encodes for proteins. Derivative of atp (camp)+ 2 sugars (lactose and glucose) Derivative of atp (camp)+ 2 sugars (lactose and glucose: ability of rna polymerase to bind near the gene, to recognize a promoter sequence, sigma factors and how they are a part of rna holoenzyme that assist the promoter. Very little capability to move they need to have a unique way to recognize and respond to it. Available in cell but not translated til appropriate condition arrive (translation control) Positive regulator increase rate because it increase ability of rna polymerase to bind to promoter. Negative regulator must be release from dna before rna pol binds and transcription can occur. Activator = inducible = turn on (positive control) Weak promoter does not promote transcription on its own. Small promoter inducer binds and changes protein, enables activator to bind to activator binding site.
