PDBsum entry 1r3m

Hydrolase

PDB id: 1r3m

Contents

Protein chains

122 a.a. *

Ligands

PO4 ×2

Waters ×101

* Residue conservation analysis

PDB id:

1r3m

Name:

Hydrolase

Title:

Crystal structure of the dimeric unswapped form of bovine seminal ribonuclease

Structure:

Ribonuclease, seminal. Chain: a, b. Synonym: seminal rnase, s-rnase, ribonuclease bs-1. Ec: 3.1.27.5

Source:

Bos taurus. Cattle. Organism_taxid: 9913. Secretion: seminal fluid

Resolution:

2.20Å R-factor: 0.211 R-free: 0.292

Authors:

R.Berisio,F.Sica,C.De Lorenzo,A.Di Fiore,R.Piccoli,A.Zagari, L.Mazzarella

Key ref:

R.Berisio et al. (2003). Crystal structure of the dimeric unswapped form of bovine seminal ribonuclease. FEBS Lett, 554, 105-110. PubMed id: 14596923 DOI: 10.1016/S0014-5793(03)01114-1

Date:

02-Oct-03 Release date: 18-Nov-03

Protein chains

P00669  (RNS_BOVIN) -  Seminal ribonuclease from Bos taurus

Seq: 150 a.a.

Struc: 122 a.a.

Enzyme reactions

• Enzyme class: E.C.4.6.1.18 - pancreatic ribonuclease.
• Reaction:
  1. an [RNA] containing cytidine + H2O = an [RNA]-3'-cytidine- 3'-phosphate + a 5'-hydroxy-ribonucleotide-3'-[RNA]
  2. an [RNA] containing uridine + H2O = an [RNA]-3'-uridine-3'-phosphate + a 5'-hydroxy-ribonucleotide-3'-[RNA]

DOI no: 10.1016/S0014-5793(03)01114-1

FEBS Lett 554:105-110 (2003)

PubMed id: 14596923

Crystal structure of the dimeric unswapped form of bovine seminal ribonuclease.

R.Berisio, F.Sica, C.De Lorenzo, A.Di Fiore, R.Piccoli, A.Zagari, L.Mazzarella.

ABSTRACT

Bovine seminal ribonuclease is a unique case of protein dimorphism, since it exists in two dimeric forms, with different biological and kinetic behavior, which interconvert into one another through three-dimensional swapping. Here we report the crystal structure, at 2.2 A resolution, of the unswapped form of bovine seminal ribonuclease. Besides completing the structural definition of bovine seminal ribonuclease conformational dimorphism, this study provides the structural basis to explain the dependence of the enzyme cooperative effects on its swapping state.

Selected figure(s)

Figure 2.
Fig. 2. a: Omit (Fo−Fc) map around a portion of the N-terminal helix including the catalytic His12. b: Omit (Fo−Fc) electron density around the hinge loop of one of the two subunits in the M=M crystal structure. Residues Ser20 and Ser21, which are fully disordered, are modeled (light gray) to show the hinge connectivity. c: Stereo diagram showing the hinge region after the superposition of a subunit of M=M (dark gray) with RNase A (medium gray) and hRNase (light gray).

Figure 3.
Fig. 3. Superposition of the C^α trace of one MxM subunit (PDB code 1BSR) (dark gray) with the corresponding M=M subunit (light gray). a: View along the approximate two-fold axis. b: A view of the C^α traces rotated by 90°.

The above figures are reprinted by permission from the Federation of European Biochemical Societies: FEBS Lett (2003, 554, 105-110) copyright 2003.

Figures were selected by an automated process.