Studies of J-connectivities and selective ¹H-¹H Overhauser effects in H₂O solutions of biological macromolecules by two-dimensional NMR experiments

Abstract

This paper demonstrates that two-dimensional (2D) NMR experiments are particularly suitable for studies of biopolymers in H₂O solution. Compared to conventional one-dimensional NMR experiments the 2D studies are much more efficient and yield with a single instrument setting a nearly complete network of J-connectivities or cross relaxation pathways involving labile protons. The use of these techniques in H₂O solutions presents a new approach for detailed studies of the backbone spatial structure in proteins and should further be of particular interest for conformational studies of nucleic acids. Here, homonuclear J-connectivities and Overhauser effects (NOE) involving labile protons were studied in the basic pancreatic trypsin inhibitor.