Nuclear magnetic resonance study of the solution structure of alpha 1-purothionin. Sequential resonance assignment, secondary structure and low resolution tertiary structure

J Mol Biol. 1987 Feb 5;193(3):571-8. doi: 10.1016/0022-2836(87)90267-1.


The solution structure of the 45-residue plant protein, alpha 1-purothionin, is investigated by nuclear magnetic resonance (n.m.r.) spectroscopy. Using a combination of two-dimensional n.m.r. techniques to demonstrate through-bond and through-space (less than 5 A) connectivities, the 1H n.m.r. spectrum of alpha 1-purothionin is assigned in a sequential manner. The secondary structure elements are then delineated on the basis of a qualitative interpretation of short-range nuclear Overhauser effects (NOE) involving the NH, C alpha H and C beta H protons. There are two helices extending from residues 10 to 19 and 23 to 28, two short beta-strands from residues 3 to 5 and 31 to 34 which form a mini anti-parallel beta-sheet, and five turns. In addition, a number of long-range NOE connectivities are assigned and a low resolution tertiary structure is proposed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antimicrobial Cationic Peptides
  • Magnetic Resonance Spectroscopy
  • Plant Proteins*
  • Protein Conformation
  • Solutions


  • Antimicrobial Cationic Peptides
  • Plant Proteins
  • Solutions
  • purothionin