Topoisomerase I Inhibitors

摘要: The helical structure of DNA was proposed in 1953 by Watson and Crick (1). Twelve years later, Vinograd collaborators (2–4) found that the helix axis can also be coiled circular DNA. This called supercoiling. finding extended to linear Pettijohn others (5–8). It is now known practically all vivo supercoiled (9). Because most functions require untwisting, importance enzymes required for this self-evident. first such enzyme identified protein ω (10).It topoisomerase I (top1) because untwisting DNA, it breaks only one two strands, whereas II (top2), initially gyrase, both. Topoisomerase type are ubiquitous, having been every prokaryotic or eukaryotic cells investigated so far with exception sea urchin sperm (11).