A potential allosteric subsite generated by domain swapping in bovine seminal ribonuclease.Vitagliano, L., Adinolfi, S., Sica, F., Merlino, A., Zagari, A., Mazzarella, L.
(1999) J Mol Biol 293: 569-577
- PubMed: 10543951
- DOI: 10.1006/jmbi.1999.3158
- Primary Citation of Related Structures:
- PubMed Abstract:
- Crystallization of Multiple Forms of Bovine Seminal Ribonuclease in the Liganded and Unliganded State
Sica, F., Adinolfi, S., Berisio, R., De Lorenzo, C., Mazzarella, L., Piccoli, R., Vitagliano, L., Zagari, A.
(1999) J Cryst Growth 196: 305
- Binding of a substrate analog to a domain swapping protein: X-ray structure of the complex of bovine seminal ribonuclease with uridylyl(2',5')adenosine.
Vitagliano, L., Adinolfi, S., Riccio, A., Sica, F., Zagari, A., Mazzarella, L.
(1998) Protein Sci 7: 1691
- Cosolute Effect on Crystallization of Two Dinucleotide Complexes of Bovine Seminal Ribonuclease from Concentrated Salt Solutions
Sica, F., Adinolfi, S., Vitagliano, L., Zagari, A., Capasso, S., Mazzarella, L.
(1997) J Cryst Growth 168: 192
- Swapping structural determinants of ribonucleases: an energetic analysis of the hinge peptide 16-22.
Mazzarella, L., Vitagliano, L., Zagari, A.
(1995) Proc Natl Acad Sci U S A 92: 3799
- Bovine seminal ribonuclease: structure at 1.9 A resolution.
Mazzarella, L., Capasso, S., Demasi, D., Di Lorenzo, G., Mattia, C.A., Zagari, A.
(1993) Acta Crystallogr D Biol Crystallogr 49: 389
Bovine seminal ribonuclease (BS-RNase) is a peculiar member of the pancreatic-like ribonuclease superfamily endowed with unique biological functions. It has been shown that native BS-RNase is a mixture of two distinct dimeric forms. The most abundant form is characterised by the swapping of the N-terminal helix ...
Bovine seminal ribonuclease (BS-RNase) is a peculiar member of the pancreatic-like ribonuclease superfamily endowed with unique biological functions. It has been shown that native BS-RNase is a mixture of two distinct dimeric forms. The most abundant form is characterised by the swapping of the N-terminal helix. Kinetic studies have shown that this dimer is allosterically regulated, whereas the minor component, in which no swapping occurs, exhibits typical Michaelian kinetics. In order to correlate the catalytic properties with the structural features of BS-RNase, we have determined the crystal structure of the BS-RNase swapping dimer complexed with uridylyl(2'-5')guanosine. The structure of the complex was refined to an R value of 0.189 at 1.9 A resolution. Surprisingly, the enzyme binds four dinucleotide molecules, all in a non-productive way. In the two active sites, the guanine base is located in the subsite that is specific for pyrimidines. This unusual binding has been observed also in complexes of RNase A with guanine-containing nucleotides (retro-binding). One of the two additional dinucleotide molecules bound to the enzyme is located on the surface of the protein in a pocket generated by crystal packing; the second was found in a cavity at the interface between the two subunits of the swapping dimer. There are indications that the interface site plays a role in the allosteric regulation exhibited by BS-RNase. This finding suggests that domain swapping may not merely be a mechanism that proteins adopt for the transition from a monomeric to oligomeric state but can be used to achieve modulations in catalytic function.
Centro di Studio di Biocristallografia, CNR, and Dipartimento di Chimica, Universita' degli Studi di Napoli "Federico II", Via Mezzocannone 4, Napoli, I-80134, Italy.