Calcium in PDB 1s81: Porcine Trypsin with No Inhibitor Bound

All present enzymatic activity of Porcine Trypsin with No Inhibitor Bound:
3.4.21.4;

The structure of Porcine Trypsin with No Inhibitor Bound, PDB code: 1s81 was solved by T.R.Transue, J.M.Krahn, S.A.Gabel, E.F.Derose, R.E.London, with X-Ray Crystallography technique. A brief refinement statistics is given in the table below:

Resolution Low / High (Å)	100.00 / 1.70
Space group	P 21 21 21
Cell size a, b, c (Å), α, β, γ (°)	76.423, 53.467, 46.605, 90.00, 90.00, 90.00
R / Rfree (%)	17.6 / 21.6

The structure of Porcine Trypsin with No Inhibitor Bound also contains other interesting chemical elements:

Sodium

(Na)

1 atom

The binding sites of Calcium atom in the Porcine Trypsin with No Inhibitor Bound (pdb code 1s81). This binding sites where shown within 5.0 Angstroms radius around Calcium atom.
In total only one binding site of Calcium was determined in the Porcine Trypsin with No Inhibitor Bound, PDB code: 1s81:

Calcium binding site 1 out of 1 in the Porcine Trypsin with No Inhibitor Bound


Mono view


Stereo pair view

A full contact list of Calcium with other atoms in the Ca binding site number 1 of Porcine Trypsin with No Inhibitor Bound within 5.0Å range: probe atom residue distance (Å) B Occ A:Ca1 b:18.1 occ:1.00 OE2 A:GLU80 2.0 18.6 1.0 O A:ASN72 2.1 12.0 1.0 O A:VAL75 2.2 14.4 1.0 H2 A:HOH520 2.2 11.3 0.5 OE1 A:GLU70 2.2 11.5 1.0 O A:HOH520 2.2 11.3 0.5 O A:HOH305 2.3 11.8 0.8 H1 A:HOH305 2.3 11.8 0.8 H1 A:HOH520 2.4 11.3 0.5 OE1 A:GLU77 2.4 16.8 0.3 H2 A:HOH305 3.0 11.8 0.8 CD A:GLU80 3.2 16.8 1.0 HA A:LEU76 3.2 22.8 0.5 C A:ASN72 3.3 11.1 1.0 CD A:GLU70 3.3 21.0 1.0 C A:VAL75 3.3 13.5 1.0 HA A:LEU76 3.3 22.6 0.5 HG3 A:GLU77 3.3 22.3 0.7 HG2 A:GLU80 3.3 15.1 1.0 CD A:GLU77 3.4 21.9 0.3 H A:GLU77 3.4 22.3 1.0 HG3 A:GLU77 3.5 24.3 0.3 HB3 A:ASN72 3.6 12.8 1.0 H A:VAL75 3.6 12.1 1.0 HA A:ILE73 3.6 14.3 1.0 H A:HIS71 3.6 15.1 1.0 CG A:GLU80 3.6 15.1 1.0 HG3 A:GLU80 3.7 15.1 1.0 H A:ASN72 3.7 10.2 1.0 OE2 A:GLU70 3.7 12.0 1.0 HA A:GLU70 3.9 10.2 1.0 HD11 A:LEU76 3.9 32.5 0.5 CG A:GLU77 4.0 24.3 0.3 CA A:LEU76 4.0 22.8 0.5 N A:LEU76 4.0 17.7 0.5 N A:LEU76 4.0 17.7 0.5 HD21 A:LEU76 4.1 26.9 0.5 CA A:LEU76 4.1 22.6 0.5 HB2 A:GLU77 4.1 18.6 0.7 N A:ASN72 4.1 10.2 1.0 CA A:ASN72 4.1 10.9 1.0 N A:GLU77 4.2 22.3 1.0 N A:ILE73 4.2 11.8 1.0 OE1 A:GLU80 4.3 15.9 1.0 N A:VAL75 4.3 12.1 1.0 HB2 A:GLU77 4.3 18.6 0.3 CG A:GLU77 4.3 22.3 0.7 CA A:ILE73 4.3 14.3 1.0 CB A:ASN72 4.3 12.8 1.0 CA A:VAL75 4.4 10.8 1.0 OE1 A:GLU77 4.4 24.7 0.7 O A:HOH339 4.4 20.2 0.7 OE2 A:GLU77 4.4 19.2 0.3 HB3 A:GLU70 4.5 12.4 1.0 HB A:VAL75 4.6 16.7 1.0 C A:LEU76 4.6 23.2 0.5 C A:LEU76 4.6 23.2 0.5 C A:ILE73 4.6 17.6 1.0 CG A:GLU70 4.6 13.9 1.0 N A:HIS71 4.6 15.1 1.0 CB A:GLU77 4.6 18.6 0.3 CB A:GLU77 4.7 18.6 0.7 CA A:GLU70 4.8 10.2 1.0 O A:HOH376 4.8 21.0 0.8 CD A:GLU77 4.9 19.8 0.7 CB A:GLU70 4.9 12.4 1.0 HG2 A:GLU77 4.9 24.3 0.3 H1 A:HOH376 4.9 21.0 0.8 H1 A:HOH339 4.9 20.2 0.7 O A:ILE73 4.9 16.4 1.0 N A:ASP74 4.9 12.9 1.0 H2 A:HOH270 5.0 12.7 0.9 CD1 A:LEU76 5.0 32.5 0.5 H A:LEU76 5.0 17.7 0.5

T.R.Transue, J.M.Krahn, S.A.Gabel, E.F.Derose, R.E.London. X-Ray and uc(Nmr) Characterization of Covalent Complexes of Trypsin, Borate, and Alcohols. Biochemistry V. 43 2829 2004.
ISSN: ISSN 0006-2960
PubMed: 15005618
DOI: 10.1021/BI035782Y