| Autor: |
R T, Todorova, V V, Rogov, K S, Vasilenko, E A, Permyakov |
| Rok vydání: |
1996 |
| Předmět: |
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| Zdroj: |
Biophysical chemistry. 62(1-3) |
| ISSN: |
0301-4622 |
| Popis: |
Three mutant forms of the ribosomal protein L7/L12 with replacements of Ser1, Met14 and Met26 to Tyr were studied by the methods of fluorescence spectroscopy, circular dichroism and microcalorimetry. The amino-acid residue Tyr14 in the protein L7/L12 Tyr14 is located in a region with a more organized structure than Tyr26 in protein L7/L12 Tyr26. The replacements Ser1--Tyr1 and Met14--Tyr14 do not affect the secondary structure of protein L7/L12. The replacement Met26--Tyr26 stabilizes the secondary structure of protein L7/L12. A pH-induced temperature transition was observed in the pH range 5.0-7.3 in protein L7/L12 Tyr14 by tyrosine fluorescence. Analogous transitions were observed for protein L7/L12 Tyr26 by Tyr fluorescence and for the wild type protein L7/L12 by Phe fluorescence. Three pH-dependent states of protein L7/L12 and its mutant forms L7/L12 Tyr1 and L7/L12 Tyr14 were found on the microcalorimetric melting curves. The characteristics of protein L7/L12 Tyr14 are very close to the wild type protein L7/L12 and it is a suitable object for studying the structure of the N-terminal part of molecule by two-dimentional 1H-NMR. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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