polylysine is a random coil at pH values below about 11, where repulsion of positive charges prevents helix formation. At pH 12, where polylysine is a neutral peptide chain, it readily forms an a-helix.

TLS Online TPP Program

#Id: 6290

#Unit 3. Fundamental Processes

Consensus Sequences

TLS Online TPP Program

#Id: 6291

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6292

#Unit 3. Fundamental Processes

The carboxy-terminal domain of the a subunit (aCTD) recognizes the Up-element (where present), whereas s regions 2 and 4 recognize the –10 and –35 regions

TLS Online TPP Program

#Id: 6293

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6294

#Unit 3. Fundamental Processes

In holoenzyme Region 1.1 of s is highly negatively charged hence region 1.1 acts as a molecular mimic of DNA

TLS Online TPP Program

#Id: 6295

#Unit 3. Fundamental Processes

An additional DNA element that binds RNA polymerase is found in some strong promoters, for example, those directing expression of the ribosomal RNA (rRNA) genes. This is called an UP-element and increases polymerase binding by providing an additional specific interaction between the enzyme and the DNA.