Studies on rat liver nuclear DNA damaged by chemical carcinogen (3'-Me DAB) and AP DNA endonuclease. I. Purification and some properties of AP DNA endonucleases in rat liver chromatin.
10.3346/jkms.1990.5.3.127
- Author:
Yoon Soo KIM
1
;
Jong Wook KIM
;
Seo Eun LEE
;
Sang Hwan OH
Author Information
1. Department of Biochemistry, Yonsei University College of Medicine, Korea.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
AP DNA endonuclease;
Purification;
Rat liver chromatin
- MeSH:
Animals;
Carcinogens;
Chromatin/*enzymology;
DNA Damage/*physiology;
DNA-(Apurinic or Apyrimidinic Site) Lyase;
Deoxyribonuclease IV (Phage T4-Induced);
Electrophoresis, Polyacrylamide Gel;
Endodeoxyribonucleases/*isolation & purification/metabolism;
Isoelectric Focusing;
Liver/drug effects/*enzymology;
Male;
Rats;
Rats, Inbred Strains;
Substrate Specificity;
p-Dimethylaminoazobenzene
- From:Journal of Korean Medical Science
1990;5(3):127-135
- CountryRepublic of Korea
- Language:English
-
Abstract:
Three kinds of apurinic/apyrimidinic (AP) DNA endonuclease, APcI, APcII, APcIII, were purified from rat liver chromatin through 1M KCl extraction, DEAE-trisacryl ion exchange chromatography. Sephadex G-150 gel filtration and AP DNA cellulose affinity chromatography. Activities of the purified APcI, APcII and APcIII were 62.5, 83.3 and 52.0 EU/mg of protein, respectively. Molecular weights of APcI, APcII and APcIII, each consisting of a single polypeptide, were 30,000, 42,000 and 13,000, and isoelectric points of them were 7.2, 6.3 and 6.2, respectively. Three enzymes showed different substrate specificities; APcI acted only on AP DNA, and APcII acted on both AP DNA and UV DNA, while APcIII acted on 3'-methyl-4-monomethylaminoazobenzene (3'-Me MAB) DNA adduct as well as AP DNA and UV DNA. These results indicate that three kinds of AP DNA endonuclease present in rat liver chromatin have structural and functional diversities.
