3RH1

X-ray Structure of a cis-proline (P114) to alanine variant of Ribonuclease A

Summary for 3RH1

• Entry DOI: 10.2210/pdb3rh1/pdb
• Related: 1FS3 1KF2 1KF3 1KF5 1KF7
• Descriptor: Ribonuclease pancreatic, CHLORIDE ION (3 entities in total)
• Functional Keywords: protei, ribonuclease fold, ribonuclease, rna, hydrolase
• Biological source: Bos taurus (bovine)
• Cellular location: Secreted: P61823
• Total number of polymer chains: 1
• Total formula weight: 13717.74

Authors

Merlino, A.,Balsamo, A.,Mazzarella, L.,Sica, F. (deposition date: 2011-04-11, release date: 2012-02-15, Last modification date: 2024-10-16)

Primary citation

Merlino, A.,Picone, D.,Ercole, C.,Balsamo, A.,Sica, F.
Chain termini cross-talk in the swapping process of bovine pancreatic ribonuclease.
Biochimie, 94:1108-1118, 2012

PubMed Abstract: 3D domain swapping is the process by which two or more protein molecules exchange part of their structure to form intertwined dimers or higher oligomers. Bovine pancreatic ribonuclease (RNase A) is able to swap the N-terminal α-helix (residues 1-13) and/or the C-terminal β-strand (residues 116-124), thus forming a variety of oligomers, including two different dimers. Cis-trans isomerization of the Asn113-Pro114 peptide group was observed when the protein formed the C-terminal swapped dimer. To study the effect of the substitution of Pro114 on the swapping process of RNase A, we have prepared and characterized the P114A monomeric and dimeric variants of the enzyme. In contrast with previous reports, the crystal structure and NMR data on the monomer reveals a mixed cis-trans conformation for the Asn113-Ala114 peptide group, whereas the X-ray structure of the C-terminal swapped dimer of the variant is very close to that of the corresponding dimer of RNase A. The mutation at the C-terminus affects the capability of the N-terminal α-helix to swap and the stability of both dimeric forms. The present results underscore the importance of the hydration shell in determining the cross-talk between the chain termini in the swapping process of RNase A.

PubMed: 22273774
DOI: 10.1016/j.biochi.2012.01.010

Experimental method

X-RAY DIFFRACTION (2.1 Å)