Is protein folding symmetric with respect to reversing the sequence order? Suppose that I have two proteins, protein A and protein B, and suppose that the sequence of amino acids of protein B is exactly the reverse of the sequence of protein A. For example (these are made-up proteins): protein A = [G,A,L,G,M,F,R] protein B = [R,F,M,G,L,A,G] Will the 3D structure of protein B be somehow identical, or perhaps the mirror image, of the 3D structure of protein A?

No! Although there is a relationship, the protein would not fold properly since the C and N terminals are reversed consider the following:

H(NH)-A-C(=O)(NH)-B-C(=O)(NH)-C-C(=O)(NH)-D-C(=O)(NH)-E-(C=O)OH

as appose to :

HO(C=O)-A-(NH)(C=O)-B-(NH)(C=O)-C-(NH)(C=O)-D-(NH)(C=O)-E-(NH)H

These are completely different molecules!

< < <