5EBX

THE CRYSTAL STRUCTURE OF ERABUTOXIN A AT 2.0 ANGSTROMS RESOLUTION

Summary for 5EBX

• Entry DOI: 10.2210/pdb5ebx/pdb
• Related: 3EBX
• Descriptor: ERABUTOXIN A, SULFATE ION (3 entities in total)
• Functional Keywords: toxin
• Biological source: Laticauda semifasciata (broad-banded blue sea krait)
• Cellular location: Secreted : P60775
• Total number of polymer chains: 1
• Total formula weight: 6949.78

Authors

Corfield, P.W.R.,Lee, T.-J.,Low, B.W. (deposition date: 1989-12-20, release date: 1990-04-15, Last modification date: 2024-11-20)

Primary citation

Corfield, P.W.,Lee, T.J.,Low, B.W.
The crystal structure of erabutoxin a at 2.0-A resolution.
J.Biol.Chem., 264:9239-9242, 1989

PubMed Abstract: The three-dimensional structure of erabutoxin a, a single-chain, 62-residue protein neurotoxin from snake venom, has been determined to 2.0-A resolution by x-ray crystal structure analysis. Molecular replacement methods were used, and the structure refined to a residual R = 0.17. The sites of 62 water molecules and 1 sulfate ion have been located and refined. The structure of erabutoxin a is very similar to that established earlier for erabutoxin b. These toxins from venom of the same snake differ in sequence only at residue 26, which is Asn in erabutoxin a and His in erabutoxin b. The substitution leads to only minor variations in intramolecular hydrogen bonding. Furthermore, the distribution of thermal parameters and the implied regional mobilities are similar in the two structures. In particular, the highly mobile character of the peripheral segment Pro44-Gly49 in both structures supports the specific role proposed for this segment in neurotoxin binding to the acetylcholine receptor. Forty-eight of the solvent sites determined are first surface positions; approximately one-half of these are equivalent to solvent sites in erabutoxin b.

PubMed: 2722828

Experimental method

X-RAY DIFFRACTION (2 Å)