Crystal structure of the bowman-birk serine protease inhibitor btci in complex with trypsin and chymotrypsin

Structure

x-ray diffraction · 5 distinct chains · 10% helix, 37% strand (DSSP).

Ligands and binding sites

• CA · Calcium ion · metal · chains T
• SO4 · Sulfate ion · ion · 9 copies · chains T, D, B, E
• GOL · Glycerol · additive · 6 copies · chains T, E, B
• EDO · 1,2-ethanediol · additive · 6 copies · chains T, B, D, E
• MRD · (4R)-2-methylpentane-2,4-diol · additive · 2 copies · chains T, B, D

Binding sites are the residues within 4.5 Å of a ligand's heavy atoms.

Pockets

2 pockets found on a 1 Å grid, 1 with a druggability of 0.5 or more.

Interfaces

8 interfaces between chains.

• D–E · 2949 Ų buried · 51 hydrogen bonds · protein-protein
• T–B · 763 Ų buried · 24 hydrogen bonds · protein-protein
• C–D · 521 Ų buried · 3 hydrogen bonds · protein-protein
• B–E · 469 Ų buried · 10 hydrogen bonds · protein-protein
• B–D · 368 Ų buried · 3 hydrogen bonds · protein-protein

Modifications

Observed in the structure: 18 disulfide (disulfide).

Compared structures

• 3RU4 · Crystal structure of the Bowman-Birk serine protease inhibitor BTCI in complex with… · the same entry in another collection · chain E against E, TM-score 1.00
• 1TNJ · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• 1TNG · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• 1TNK · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• 1TNL · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• 1TNI · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• 1TNH · Prediction of novel serine protease inhibitors · a predicted model of the same protein · chain T against A, TM-score 0.99
• P00766 · AlphaFold monomer V2.0 prediction for chymotrypsinogen a (P00766) · a predicted model of the same protein · chain E against A, TM-score 0.98

Analyse

• Open in the research workbench: secondary structure, accessibility, pockets, interfaces, conservation, variants, modifications, peptides and crosslinks on the 3D structure
• Every structure of UniProt P00760
• Every structure of UniProt P17734
• Every structure of UniProt P00766
• Elsewhere: RCSB PDB 3RU4 · PDBe 3RU4 · UniProt P00760 · UniProt P17734 · UniProt P00766