1BSR

BOVINE SEMINAL RIBONUCLEASE STRUCTURE AT 1.9 ANGSTROMS RESOLUTION

Summary for 1BSR

• Entry DOI: 10.2210/pdb1bsr/pdb
• Descriptor: BOVINE SEMINAL RIBONUCLEASE, SULFATE ION (3 entities in total)
• Functional Keywords: hydrolase(phosphoric diester, rna)
• Biological source: Bos taurus (cattle)
• Cellular location: Secreted: P00669
• Total number of polymer chains: 2
• Total formula weight: 27937.72

Authors

Mazzarella, L. (deposition date: 1993-04-28, release date: 1993-10-31, Last modification date: 2024-11-20)

Primary citation

Mazzarella, L.,Capasso, S.,Demasi, D.,Di Lorenzo, G.,Mattia, C.A.,Zagari, A.
Bovine seminal ribonuclease: structure at 1.9 A resolution.
Acta Crystallogr.,Sect.D, 49:389-402, 1993

PubMed Abstract: The crystal structure of bovine seminal ribonuclease, a homodimeric enzyme closely related to pancreatic ribonuclease, has been refined at a nominal resolution of 1.9 A employing data collected on an electronic area detector. The final model consists of two chains containing 1990 non-H atoms, seven sulfate anions and 113 water molecules per asymmetric unit. The unit-cell parameters are a = 36.5 (1), b = 66.7 (1) and c = 107.5 (2) A, space group P22(1)2(1). The R factor is 0.177 for 16 492 reflections in the resolution range 6.0-1.9 A and the deviations from ideal values of bond lengths and bond angles are 0.020 A and 3.7 degrees, respectively. The molecule is formed by two pancreatic like chains, which have their N-terminal segments interchanged so that each active site is formed by residues from both subunits. The two chains are related by a non-crystallographic twofold symmetry and are covalently linked by two consecutive disulfide bridges, which form an unusual sixteen-membered ring across the dimer interface. The deviations from the molecular symmetry, the hydration shell and the sulfate-binding sites are also discussed in relation to the known structure of the pancreatic enzyme.

PubMed: 15299514
DOI: 10.1107/S0907444993003403

Experimental method

X-RAY DIFFRACTION (1.9 Å)