1CDT

CARDIOTOXIN V4/II FROM NAJA MOSSAMBICA MOSSAMBICA: THE REFINED CRYSTAL STRUCTURE

Summary for 1CDT

• Entry DOI: 10.2210/pdb1cdt/pdb
• Descriptor: CARDIOTOXIN VII4, PHOSPHATE ION (3 entities in total)
• Functional Keywords: cytotoxin
• Biological source: Naja mossambica (Mozambique cobra)
• Cellular location: Secreted : P01452
• Total number of polymer chains: 2
• Total formula weight: 13644.58

Authors

Rees, B.,Bilwes, A.,Samama, J.P.,Moras, D. (deposition date: 1990-05-17, release date: 1991-07-15, Last modification date: 2024-11-06)

Primary citation

Rees, B.,Bilwes, A.,Samama, J.P.,Moras, D.
Cardiotoxin VII4 from Naja mossambica mossambica. The refined crystal structure.
J.Mol.Biol., 214:281-297, 1990

PubMed Abstract: The crystal structure of cardiotoxin VII4 from Naja mossambica mossambica was refined to 2.5 A resolution. Fifty ordered solvent sites were localized and included in the refinement. The final R factor is 0.197 (lambda/(2sin theta) less than 5 A; F greater than 3 sigma). The three-dimensional structure is characterized by two beta-sheets. Of particular interest is the two-stranded beta-sheet in the N-terminal region. This shows a large right-handed twist and, though strongly connected to the core of the molecule, and in particular to the C-terminal end, protrudes out of the bulk of the molecule. The segment of four amino acid residues connecting the two strands of this sheet is particularly exposed. It contains an invariant proline residue that has probably an important structural role, and is completely hydrophobic. Two other conserved hydrophobic zones were identified; the largest extends over the second and third loops, on one side only of the molecule. All side-chains of invariant hydrophobic character (except proline residues) belong to one of these three zones. Also discussed are the dimeric assembly and the rather loose packing in the crystal. The three-dimensional structure is compared with that of short and long alpha-neurotoxins. Comparison with two-dimensional nuclear magnetic resonance results on the 68% homologous cardiotoxin CT X IIb shows an excellent overall agreement. A few differences are probably genuine.

PubMed: 2370666
DOI: 10.1016/0022-2836(90)90161-E

Experimental method

X-RAY DIFFRACTION (2.5 Å)