Hi all,
my problem is the following: I have in my template an alpha helix of around 20 residues, and in my model I have to extend it by forcing the secondary structure
(additional residues are not present in the template). The problem is that, both by introducing secondary structure restraints in the whole segment or only in the additional residues, I'm not able to obtain a straightened helix (the total number of alpha helix residues will be around 54), since Modeller introduces a strange bending in the helix (maybe because it is "too long"?). I would like simply to extend the starting helix in the same direction (that is, by keeping the starting helix axis up to the end). Is there a way (like another restraint to add) to avoid this "curvature" ?

Thanks in advance

---

Get news, entertainment and everything you care about at Live.com. Check it out!