Toll-like receptors are immunoreceptors for the detection of pathoden derived mo
ID: 53516 • Letter: T
Question
Toll-like receptors are immunoreceptors for the detection of pathoden derived molecules. Human TLR4 is a membrane protein with an N-terminal extracellular domain and a C-terminal cytosolic domain connected by a single transmembrane alpha helix. The sequence of the transmembrane helix is IIGVSVLSVLVVSVVAVLVY (20 amino acids). Estimate the thickness of the cell membrane according to structural features of the alpha helix. Draw a simple cartoon figure of TLR4 with the alpha helix embedded in the membrane and explain why this alpha helix is rich of hydrophobic residues. (The cartoon of the alpha helix should show the correct length and handedness of the alpha helix).
Someone please please help me! I already calculated the thickness to be 30 A. But please let me know if you think this is incorrect. I mainly confused on how to draw a cartoon of this..?
Explanation / Answer
The thickness can be calculated as:
First we divide the number of amino acids by 3.6 turns
= 20/3.6
= 5.56
Now multiplying this number with 5.4 for total turns we get
= 5.56 X 5.4
= 30.024 which is approximately 30