原卟啉（PP）和血卟啉（HP）对DNA空间结构微观光敏损伤的特征

原卟啉（ＰＰ）和血卟啉（ＨＰ）对ＤＮＡ空间结构微观光敏损伤的特征许以明，张志义（中国科学院生物物理研究所北京１００１０１）ＣｈａｒａｃｔｅｒｏｆＭｉｃｒｏｃｏｓｍｉｃａｎｄＰｈｏｔｏｓｅｎｓｉｔｖｅＤａｍａｇｅｏｆＰＰａｎｄＨＰｔｏＴｈｅｓｐａｃｅＳ...

Character of Microcosmic and Photosensitve Damage of PP and HP to Thespace Structure of DNA

Abstract Protoporphyrin （PP）and Hematoporphyrin （HP） are important components of anticancer drug HPD. Authors applied Raman spectroscopyic technology．A lot of important information about the damage of DNA space structure （phosphate backbone， B-form conformation， deoxyribose，bases， in- terbase hydrogen bonds，etc. ） was obtained simultaneously. The results areas follows：（1） Character of microcosmic and photosensitive damage of the space structure of 4％calf thymus DNA which were added with 7．5×10~(-5)mmol／L PP and HP，respectively， and irradiated are the same， but the degree of dam-age is diIferent：the damage of the former to the DNA is weaker. Only of A part of deoxyriboses and bases，involving vertical hase-base stacking interac-tions， were damaged． The damage of the latter to the DNA is stronger． The intact DNA molecule was damaged ； the scissions of double-and single－stranded DNA； the B-form conformation decreased； there were the breakage of inter-base hydrogen bonds.Each group of deoxyribose and base（A，G，C，T）were damaged in its degree. Therefore the damage of HP to calf thymus DNA is stronger than that of PP to the DNA in vitro under the same conditions. （2）Serious degree of demage to bases is in order adenine， guanine，thymine and cvtosine， It is different from DHE.