Raman spectroscopic study of microcosmic photodamage of the space structure of DNA sensitized by Yangzhou heamatoporphyrin derivative and Photofrin II

摘要

After calf thymus DNA has been photodamaged by Yangzhou haematoporphyrin derivative (YHPD) or Photofrin II, the Raman characteristic frequencies and the intensities of the bands assigned to various groups of the components of DNA change considerably. As a result of damage, homogeneous B-form calf thymus DNA becomes a mixture containing: (1) modified B-form DNA, which is shorter than the original because of double-helical DNA scission; (2) single-stranded DNA due to the breakage of some H-bonds and the lack of some bases, etc.