PDBsum entry 5e5t

Antimicrobial protein

PDB id: 5e5t

Contents

Protein chains

63 a.a.

63 a.a.

Ligands

FMT ×4

EDO ×3

Waters ×247

References listed in PDB file

Key reference

• Title: Radiation damage and racemic protein crystallography reveal the unique structure of the gasa/snakin protein superfamily.
• Authors: H.Yeung, C.J.Squire, Y.Yosaatmadja, S.Panjikar, G.López, A.Molina, E.N.Baker, P.W.Harris, M.A.Brimble.
• Ref.: Angew Chem Int Ed Engl, 2016, 55, 7930-7933. [DOI no: 10.1002/anie.201602719]
• PubMed id: 27145301

Abstract

Proteins from the GASA/snakin superfamily are common in plant proteomes and have diverse functions, including hormonal crosstalk, development, and defense. One 63-residue member of this family, snakin-1, an antimicrobial protein from potatoes, has previously been chemically synthesized in a fully active form. Herein the 1.5 Å structure of snakin-1, determined by a novel combination of racemic protein crystallization and radiation-damage-induced phasing (RIP), is reported. Racemic crystals of snakin-1 and quasi-racemic crystals incorporating an unnatural 4-iodophenylalanine residue were prepared from chemically synthesized d- and l-proteins. Breakage of the C-I bonds in the quasi-racemic crystals facilitated structure determination by RIP. The crystal structure reveals a unique protein fold with six disulfide crosslinks, presenting a distinct electrostatic surface that may target the protein to microbial cell surfaces.