title: Alterations in the activities of DNA topoisomerase enzymes and O6-methylguanine-DNA-methyltransferase in septic rat liver.
abstract: To understand the genomic changes contributing to the various metabolic derangements in sepsis and septic shock, we measured the activities of the following liver enzymes intimately associated with DNA function: (1) DNA topoisomerases I and II (topo I and topo II) controlling DNA conformation in mammalian nuclei, and (2) O6-methylguanine-DNA-methyltransferase (MT) capable of removing the methyl groups from the O6-position of guanine in DNA. We found that in septic rat livers the specific activities (units/mg protein) of topo II and MT were elevated by 1.4- and 1.6-fold, respectively, over the sham-operated controls (P less than 0.001). There was no significant difference in topo I activity. We believe that peritonitis sepsis alters topo II levels modulating the selective pretranscriptional changes in chromatin and that MT functions as a cellular stress protein.
authors.affiliation: Department of Surgery, University of Health Sciences/Chicago Medical School, IL 60064.
authors.forename: K S
authors.initials: KS
authors.lastname: Srivenugopal
authors.forename: W
authors.initials: W
authors.lastname: Schumer
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D004247:DNA / Q000378:metabolism; D004264:DNA Topoisomerases, Type I / Q000378:metabolism*; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004278:DNA, Superhelical / Q000378:metabolism; D008099:Liver / Q000201:enzymology* / Q000648:ultrastructure; D008297:Male; D008780:Methyltransferases / Q000378:metabolism*; D009690:Nucleic Acid Conformation; D019853:O(6)-Methylguanine-DNA Methyltransferase; D010538:Peritonitis; D051381:Rats; D011919:Rats, Inbred Strains; D018805:Sepsis / Q000201:enzymology* / Q000209:etiology
chemical_list: D004278:DNA, Superhelical; D004247:DNA; D008780:Methyltransferases; D019853:O(6)-Methylguanine-DNA Methyltransferase; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II