Crystal structure of the dimeric unswapped form of bovine seminal ribonuclease

• Published in: FEBS letters Vol. 554; no. 1-2; pp. 105 - 110
• Main Authors: Berisio, R, Sica, F, De Lorenzo, C, Di Fiore, A, Piccoli, R, Zagari, A, Mazzarella, L
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 06.11.2003
• Subjects: Animals; BS-RNase, bovine seminal ribonuclease; Cattle; Conformational dimorphism; Crystal structure; Crystallization; Crystallography, X-Ray; Dimerization; hRNase, human pancreatic ribonuclease; M, monomeric BS-RNase; M=M, unswapped form of BS-RNase; Male; Models, Molecular; Molecular Structure; MxM, dimeric form of BS-RNase in which the chains swap their N-terminal helices; Protein Conformation; Protein Isoforms - chemistry; Protein Structure, Quaternary; Protein Subunits - chemistry; RI, ribonuclease inhibitor; Ribonuclease; Ribonucleases - chemistry; rmsd, root mean square deviation; RNase A, bovine pancreatic ribonuclease; Semen - enzymology; Three-dimensional domain swapping; MxM; Conformational dimorphism; RI; rmsd; Ribonuclease; M=M; M; RNase A; Three-dimensional domain swapping; BS-RNase; Crystal structure; hRNase
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(03)01114-1

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 Å 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.