1.97.1.12 | 20 |
100 |
analysis of thermostability of oligomeric PSI complexes. The thermal profile of the spectral shift of alpha-helices bands confirms the same two temperature intervals for PSI monomers and only one interval for trimers. Spectra at 20-100°C show distinct changes in the Amide I region of PSI complexes as a function of the rising temperature. Absorbance at the Amide I maximum of PSI monomers, gradually drops in two temperature intervals, i.e. 60-75°C and 80-90°C. In contrast, absorbance at the Amide I maximum of PSI trimers drops only in one temperature interval 80-95°C. Spectral changes of PSI trimers and monomers heated up to 100°C are irreversible due to protein denaturation and non-specific aggregation of complexes leading to new absorption bands. Thermal denaturation profiles, detailed overview, The enzyme shows denaturation at the monomer-monomer-interface at over 60°C, and denaturation/aggregation at the trimer-lipid interface at over 80°C. Oligomerization is one strategy to increase thermostability of PSI complexes |
746500 |