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Updated: Aug 18, 2026

Neutron Crystallography Data Collection and Processing for Modelling Hydrogen Atoms in Protein Structures
Published on: December 1, 2020
Crystal structure of alpha-hordothionin at 1.9 Angstrom resolution
Kenneth A Johnson1, Eunsung Kim, Martha M Teeter
1Department of Chemistry, University of Texas at El Paso, 79968, USA.
Abstract:
Crystal structure of ubiquitous toxin from barley alpha-hordothionin (alpha-HT) has been determined at 1.9A resolution by X-ray crystallography. The primary sequence as well as the NMR solution structure of alpha-HT firmly established that alpha-HT belongs to a family of membrane active plant toxins-thionins. Since alpha-HT crystallized in a space group (P4(1)2(1)2) that is different from the space group (I422) of previously determined alpha(1)- and beta-purothionins, and visocotoxin A3, therefore, it provided independent information on protein-protein interactions that may be relevant to the toxin mechanism. The structure of alpha-HT not only confirms overall architectural features (crambin fold) but also provides an additional confirmation of the role for crucial solute molecules, that were postulated to be directly involved in the mechanism of toxicity for thionins.
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