Avtor/Urednik		Martin, John R; Jerala, Roman; Kroon-Žitko, Louise; Žerovnik, Eva; Turk, Vito; Waltho, Jonathan P
Naslov		Structural characterization of human stefin A in solution and implications for binding to cystein proteinases
Tip		članek
Vir		Eur J Biochem
Vol. in št.		Letnik 225, št. 3
Leto izdaje		1994
Obseg		str. 1181-94
Jezik		eng
Abstrakt		Stefin A is a member of the cystatin superfamily of proteins which are tight and reversibly binding inhibitors of the papain-like cysteine proteinases. The 1H-NMR and 15N-NMR resonances of human stefin A have been sequentially assigned using two-dimensional homonuclear and heteronuclear NMR techniques in conjunction with three-dimensional heteronuclear methods. Characteristic sequential and medium range NOE contacts, J constants and hydrogen exchange data have been used to identify the secondary structural elements of the protein which consists of five anti-parallel beta-strands and a single alpha-helix. There is much similarity between the secondary structural features of stefin A and the homologous protein stefin B in its complex with papain ŠStubbs, M. T., Laber, B., Bode, W., Huber, R., Jerala, R., Lenarcic, B. & Turk, V. (1990) EMBO. J. 9. 1939-1947Ć but also some important differences in regions which are fundamental to the binding event. The principal difference is the presence of two conformationally unrestricted regions in stefin A that form two of the components of the tripartite wedge which docks into the active site of the target proteinase. Specifically, these regions are the five N-terminal residues and the second binding loop, which form a turn and a short helix respectively, in the bound conformation of stefin B.
Deskriptorji		CYSTATINS CYSTEINE PROTEINASES BINDING SITES ELECTRON SPIN RESONANCE SPECTROSCOPY MOLECULAR SEQUENCE DATA MOLECULAR STRUCTURE NUCLEAR MAGNETIC RESONANCE PEPTIDE MAPPING PROTEIN CONFORMATION PROTEIN STRUCTURE, SECONDARY RECOMBINANT PROTEINS