[Study of the conformational properties of C-terminal fragments of histones H1, H5, and beta-endorphin by circular dichroism].

Circular dichroism technique has been used for investigating the conformation of histone H1 and H5 C-terminal fragments and beta-endorphin. It has been shown that in aqueous solution these polypeptides adopt preferably the left-handed helical conformation of the poly-L-proline II type. The linear temperature dependence of the CD value during solution heating was found to be broken in the temperature interval between 50 and 55 degrees C. It was supposed to occur due to the conformation destruction.