On 2/26/18 10:05 AM, Komjati Kornel wrote: > I would like to model a protein with multiple chains (A,B,C,D) as an > entire rigid body. > Unfortunately I cannot find a way to do this, it seems like that a rigid > body can only contain one protein chain.

Sure, that's straightforward. A rigid body is simply represented internally as a set of particles - it doesn't care whether those particles are in the same chain or different chains. You don't say how you're doing the modeling, but if you're using a PMI topology file, just use the same rigid body number for all of the domains.

Ben