The near and far ultraviolet (UV) circular dichroism (CD) spectra of human haptoglobin 1-1 (Hp 1-1) and of one of its complexes with horse ferrihemoglobin are presented. Comparison of the far UV spectrum of the complex with the appropriate weighted sum of its components gives a calculated spectrum that is slightly more negative than the experimental at every wavelength. The small deviation from additivity indicates that if any changes in secondary structure occur on complex formation, they are very small. The basic chain folding of the hemoglobin is preserved, at least with regard to helix content. Changes in side-chain and heme optical activity cause similar deviations from additivity in the near UV and these may be responsible for the observed far UV deviations.
|Original language||English (US)|
|Number of pages||8|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Dec 3 1971|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology