Standard chemical shifts of random extended chain structures:

More info in:

¹H chemical shifts of amino acids

¹³C chemical shifts of amino acids

Average ¹HA, ¹HN and ¹⁵N chemical shifts in random coil

Easy spin system identification from:

• HA-HB cross-peak in a  COSY-DQF experiment.
• Typical pattern in a TOCSY experiment.

The epsilon-methyl resonances proteins can be identified and subsequently correlated either to CB or to HG spins ( 94JB787 ), and to the CB/HB pair ( 95JMRB197-107 ) in 13C-labeled.

Standard average chemical shift values used in determination of secondary structure by means of the CSI method:

HA: 4.52
CA: 55.2
CO: 177.0

Thus:

          HELIX           B STRAND          COIL
             CA      CO       CA      CO           CA      CO
            57.8    178.5     54.1    176.1      55.7    176.3

More info in: ¹³CA and ¹³CO chemical shifts according to secondary structure.