Inhibitory action of C22-fatty acids on DNA polymerases and DNA topoisomerases.
نویسندگان
چکیده
We reported previously that unsaturated linear-chain fatty acids of the cis-configuration with a C18-hydrocarbon chain such as linoleic acid (cis-9, 12-octadecadienoic acid, C18:2) could potently inhibit the activity of mammalian DNA polymerases (Biochim Biophys Acta 1308: 256-262, 1996). In this study, we investigated the inhibitory effects of cis-type C22-fatty acids including cis-7,10,13,16,19-docosapentaenoic acid (DPA, C22:5) and cis-4,7,10,13,16,19-docosahexaenoic acid (DHA, C22:6) on mammalian DNA polymerases and human DNA topoisomerases. Cis-13,16-docosadienoic acid (C22:2) was the strongest inhibitor of both DNA polymerases and topoisomerases of all C22-fatty acids tested. The inhibitory tendency by the fatty acids on DNA polymerases was the same as that of DNA topoisomerases, and the second strongest inhibitor was cis-13,16,19-docosatrienoic acid (C22:3). The energy-minimized three-dimensional structures of the fatty acids were calculated and it was found that a length of 19-21 Angstrom and width of more than 7 Angstrom in C22-fatty acid structure were important for enzyme inhibition. The three-dimensional structure of the active site of both DNA polymerases and topoisomerases must have a pocket to join C22:2, and this pocket was 19.41 Angstrom long and 9.58 Angstrom wide.
منابع مشابه
Mechanism of Growth Inhibition of Human Cancer Cells by Conjugated Eicosapentaenoic Acid, an Inhibitor of DNA Polymerase and Topoisomerase
DNA topoisomerases (topos) and DNA polymerases (pols) are involved in many aspects of DNA metabolism such as replication reactions. We found that long chain unsaturated fatty acids such as polyunsaturated fatty acids (PUFA) (i.e., eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) inhibited the activities of eukaryotic pols and topos in vitro, and the inhibitory effect of conjugated fa...
متن کاملTopoisomerase Inhibitors and Types of Them
Objective: In this paper, we have introduced topoisomerase inhibitors, mechanism of action and types of them. DNA topoisomerases are ubiquitous enzymes that catalyze essential enzymes to solve the topological problems accompanying key nuclear processes such as DNA replication, transcription, repair and chromatin assembly by introducing temporary single or double strand breaks in the DNA. Result...
متن کاملTopoisomerase Inhibitors and Types of Them
Objective: In this paper, we have introduced topoisomerase inhibitors, mechanism of action and types of them. DNA topoisomerases are ubiquitous enzymes that catalyze essential enzymes to solve the topological problems accompanying key nuclear processes such as DNA replication, transcription, repair and chromatin assembly by introducing temporary single or double strand breaks in the DNA. Result...
متن کاملTamoxifen inhibits topoisomerases, depletes mitochondrial DNA, and triggers steatosis in mouse liver.
Although tamoxifen can trigger steatohepatitis, the mechanism of steatosis is unclear. We hypothesized that this DNA-intercalating, cationic amphiphilic drug could accumulate within mitochondria to impair fatty acid oxidation, respiration, and mitochondrial DNA relaxation and synthesis. We studied the in vitro effects of tamoxifen on topoisomerases and mouse liver mitochondria and its in vivo h...
متن کاملTransformation of Rapeseed (Brassica napus L.) Plants with Sense and Antisense Constructs of the Fatty Acid Elongase Gene
The biosynthetic pathways of saturated and unsaturated fatty acids consist of many steps controlled by various enzymes. One of the methods for improving oil quality is to change the fatty acid profile through genetic manipulation which requires isolation and characterization of the genes and other cis-acting elements, such as the promoter, involved in fatty acid biosynthesis. b-ketoacyl-CoA syn...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- International journal of molecular medicine
دوره 18 4 شماره
صفحات -
تاریخ انتشار 2006