In Chapter 9, we considered the dimensions of the double helix (see Figure 9.15). In an

Question:

In Chapter 9, we considered the dimensions of the double helix (see Figure 9.15). In an α helix of a protein, there are 3.6 amino acids per complete turn. Each amino acid advances the α helix by 0.15 nm; a complete turn of an α helix is 0.54 nm in length. As shown in Figure 12.6, two α helices of a transcription factor occupy the major groove of the DNA. According to Figure 12.6, estimate the number of amino acids that bind to this region. How many complete turns of the α helices occupy the major groove of DNA?