Natural abundant15N NMR detection of polypeptide and protein

Conclusion It has been demonstrated that it is possible to detect the natural abundant¹⁵N signals using 2-D HMQC method. For large molecules like lysozyme, the saturation transfer effect is not important and the water signal can be suppressed with presaturation method. Since the pulse field gradient can reduce the signal intensities, whent ₁ noise is not strong, PFG could not enhance the S/N ratio.