1H-n.m.r. study of the solution properties and secondary structure of neurotoxin III from the sea anemone Anemonia sulcata.
RS Norton, K Cross, V Braach-Maksvytis, E Wachter
Biochem J | Published : 1993
The solution properties, secondary structure and global fold of the 27-residue polypeptide neurotoxin III (ATX III), from the sea anemone Anemonia sulcata, have been investigated using high-resolution 1H-n.m.r. spectroscopy. Studies of the concentration dependence of the n.m.r. spectrum indicate that the molecule self-associates in the millimolar concentration range useable for n.m.r. analysis, the association being less pronounced at acidic pH values. The dependence on pH of association implies that electrostatic interactions play a role in this process, while the significant concentration-dependent shifts of the aromatic resonances of Tyr-7 and Trp-13 indicate that hydrophobic interactions..View full abstract