PDBsum entry 3vts

Toxin

PDB id: 3vts

Contents

Protein chains

61 a.a.

Waters ×49

PDB id:

3vts

Name:

Toxin

Title:

Crystal structure of a three finger toxin from snake venom

Structure:

Cytotoxin 1. Chain: a, b. Synonym: hemolytic protein 12b, three finger toxin

Source:

Hemachatus haemachatus. Ringhals. Organism_taxid: 8626

Resolution:

2.43Å R-factor: 0.237 R-free: 0.281

Authors:

C.Jobichen,J.Sivaraman

Key ref:

V.M.Girish et al. (2012). Identification and structural characterization of a new three-finger toxin hemachatoxin from Hemachatus haemachatus venom. Plos One, 7, e48112. PubMed id: 23144733

Date:

06-Jun-12 Release date: 07-Nov-12

Protein chains

B3EWH9  (3SBH_HEMHA) -  Three-finger hemachatoxin from Hemachatus haemachatus

Seq: 61 a.a.

Struc: 61 a.a.

Plos One 7:e48112 (2012)

PubMed id: 23144733

Identification and structural characterization of a new three-finger toxin hemachatoxin from Hemachatus haemachatus venom.

V.M.Girish, S.Kumar, L.Joseph, C.Jobichen, R.M.Kini, J.Sivaraman.

ABSTRACT

Snake venoms are rich sources of biologically active proteins and polypeptides. Three-finger toxins are non-enzymatic proteins present in elapid (cobras, kraits, mambas and sea snakes) and colubrid venoms. These proteins contain four conserved disulfide bonds in the core to maintain the three-finger folds. Although all three-finger toxins have similar fold, their biological activities are different. A new three-finger toxin (hemachatoxin) was isolated from Hemachatus haemachatus (Ringhals cobra) venom. Its amino acid sequence was elucidated, and crystal structure was determined at 2.43 Å resolution. The overall fold is similar to other three-finger toxins. The structure and sequence analysis revealed that the fold is maintained by four highly conserved disulfide bonds. It exhibited highest similarity to particularly P-type cardiotoxins that are known to associate and perturb the membrane surface with their lipid binding sites. Also, the increased B value of hemachotoxin loop II suggests that loop II is flexible and may remain flexible until its interaction with membrane phospholipids. Based on the analysis, we predict hemachatoxin to be cardiotoxic/cytotoxic and our future experiments will be directed to characterize the activity of hemachatoxin.