Sandbox Reserved 162: Difference between revisions

This structure of Interleukin-6 was crystallized at 1.9Å. IL-6 is a monomer of 185 amino acids produced from T-Cells, macrophages, and endothelial cells found on a single gene at locus 7p21. It contains five alpha-helices and four of these helices constitute a classical four-helix bundle with the fifth helix located in the CD loop. The four helices that form the four-helix bundle are arranged so that the helices two run in the same direction and two in the opposite direction. The N-terminal 18 amino acids of IL-6 are not visible in electron density maps and consequently have not been modeled. The first long helix extends from Ser21 to Ala45 and is connected to a parallel helix by a 25 amino acid loop. The next helix extends from Glu80 to Gln102. A short connection formed from Asn103 to Ser108 joins this helix to the next helix (which does not run parallel to it). This third helix extends from Glu109 to Lys129 and is followed by another amino acid loop which includes a short helix of three turns (Pro141-Gln152). The last helix, running parallel to the third, extends from Gln156 to Arg182.