Figure compiles the read-out and expected BE-codes for all residues of GB1 except M1, which was missing in the conventional CANH. A judicious choice of intensity threshold for small peaks (shown with a horizontal dotted line) reduces the incorrect BE-code assignment. One must be careful with Gly that appears as if Group B ([010]) while it has no sidechain. This is because only the BE-2 pulse refocuses the Ca spins for Gly with δCa >45 ppm (See Figure ). Because the BE-code for K4 and A23 could not be identified due to the signal overlap to each other in the BE-CANH spectrum, they should be read in the BE-CAcoNH data (Figure ) recorded using the pulse sequence shown in Figure . Overall, 53 out of 55 residues were identified with the correct BE-code. The only two failed residues (K4 and K13) were incorrectly identified as Group A (for [101]) instead of Group B (for [010]). Actually, these two Lys residues had the Cβ chemical shift strongly downfield shifted (35.9 and 38.3 ppm, respectively), being well outside the standard deviation in the BMRB statistics for Lys, and step well into the Cβ shift range of Group A. This is possibly because the F,Y and c1 dihedral angles for K4 and K13, major influencing factors for the Cβ secondary shifts , are in the less occurring region, being quite isolated from those of the other Lys residues (Figure ). Thus, we conclude these errors were due to the abnormal secondary chemical shifts of K4 and K13 from their particular conformation. This is highlighting the limitation of the present method.