ATOMIC RESOLUTION STRUCTURES OF RNASE A AT SIX PH VALUES

Autor: R. BERISIO, V. S. LAMZIN, K. S. WILSON, A. ZAGARI, L. MAZZARELLA, SICA, FILOMENA
Přispěvatelé: Sica, Filomena, Mazzarella, Lelio, Zagari, Adriana, Lamzin, V. S., Wilson, K. S., Berisio, R., Berisio, R, Zagari, A, R., Berisio, V. S., Lamzin, K. S., Wilson, A., Zagari, L., Mazzarella
Rok vydání: 2002
Zdroj: D52 (2002): 441–450.
info:cnr-pdr/source/autori:Berisio R., Sica F., Lamzin V. S., Wilson K. S., Zagari A., Mazzarella L../titolo:Atomic resolution structures of rnase A at six ph values/doi:/rivista:/anno:2002/pagina_da:441/pagina_a:450/intervallo_pagine:441–450/volume:D52
Popis: The diffraction pattern of protein crystals extending to atomic resolution guarantees a very accurate picture of the molecular structure and enables the study of subtle phenomena related to protein functionality. Six structures of bovine pancreatic ribonuclease at the pH* values 5.2, 5.9, 6.3, 7.1, 8.0 and 8.8 and at resolution limits in the range 1.05-1.15A have been refined. An overall description of the six structures and several aspects, mainly regarding pH-triggered conformational changes, are described here. Since subtle variations were expected, a thorough validation assessment of the six refined models was first carried out. Some stereochemical parameters, such as the N[bond]C(alpha)[bond]C angle and the pyramidalization at the carbonyl C atoms, indicate that the standard target values and their weights typically used in refinement may need revision. A detailed comparison of the six structures has provided experimental evidence on the role of Lys41 in catalysis. Furthermore, insights are given into the structural effects related to the pH-dependent binding of a sulfate anion, which mimics the phosphate group of RNA, in the active site. Finally, the results support a number of thermodynamic and kinetic experimental data concerning the role of the disulfide bridge between Cys65 and Cys72 in the folding of RNase A.
Databáze: OpenAIRE
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