Biomedical Engineering Reference
In-Depth Information
At q values starting from 4 and below i.e in the presence of small amount of gelatin, BSA in
mixture change the secondary and the local tertiary structures of BSA and especially its
thermoaggregation behaviour. At the same time, the only small change in calorimetric
enthalpy and co-operativity, in the presence of gelatin is observed (Table 1).
Figure 11. Antonov et al. “Structural investigation of the interaction between bovine serum albumin and
acid gelatin in water”.
An excess gelatin (1<q<0.4 ) induces slightly more significant structural changes. The
partial folding, associated with an increase in alpha-helical content
,
shifts the onset
temperature of thermoaggregation to higher temperatures. These changes are clear indication
on an interaction between BSA and gelatin. This finding is consistent with turbidimetric and
DLS results of the thermoaggregation study, which show that gelatin acts as a stabilizer at
low /BSA/gelatin ratios. An excess of gelatin has an additional effect on the secondary
structure of BSA. With decreasing q up to q=0.4 (cf. Figure 5) the ratio
222
/
209
becomes less
than unity; that observation clearly indicates the formation of
+ structures, i.e., BSA
consists of separated segments of alpha and -structures.
The results of fluorescence analysis has shown quenching of fluorescence and the
absence of any shift in the wavelength of the maximum of the intrinsic fluorescent emission
that indicates on small changes in protein conformation. In proteins that contain all three
aromatic aminoacids, fluorescence is usually dominated by the contribution of the tryptophan
Search WWH ::
Custom Search