Question

Which of the following is untrue about Backbone Model Building Step?

(a) Once optimal alignment is achieved, residues in the aligned regions of the target protein can assume a similar structure as the template proteins

(b) Coordinates of the corresponding residues of the template proteins can be simply copied onto the target protein

(c) If the two residues differ, everything other than the backbone atoms can be copied

(d) If the two aligned residues are identical, coordinates of the side chain atoms are copied along with the main chain atoms

The question was asked in an international level competition.

The question is from Ab Initio Protein Structural Prediction & Homology Modeling topic in portion Protein Tertiary Structure Prediction of Bioinformatics

Answer 1

Correct choice is (c) If the two residues differ, everything other than the backbone atoms can be copied

The best I can explain: Option “Once optimal alignment is achieved, residues in the aligned regions of the target protein can assume a similar structure as the template proteins” and “Coordinates of the corresponding residues of the template proteins can be simply copied onto the target protein” mean the same. If the two residues differ, only the backbone atoms can be copied. The side chain atoms are rebuilt in a subsequent procedure.

In backbone modeling, it is simplest to use only one template structure. The structure with the best quality and highest resolution is normally chosen if multiple options are available.