AssignFit: A program for simultaneous assignment and structure refinement from solid-state NMR spectra

► AssignFit is a program for assignment of solid-state NMR anisotropic restraints. ► AssignFit is a program within the XPLOR-NIH package. ► It minimizes the difference between experiment and data calculated from a structural model. ► The methods are demonstrated for α-helical and β-barrel integral membrane proteins.