[modeller_usage] side-chain chi1 different from the templates

Dear Modeller's

I have built a 3D model on 4 structures aligned from Clustalw. In the model built, there is a threonine that bears a dihedral angle different from all equivalent threonines of the templates. Locally I cannot see why this threonine should be different. Would you help me to explain this unprecedented side-chain orientation ?

Thank you Aline