翻訳と辞書 Words near each other ・ Type Ia sensory fiber ・ Type Ia supernova ・ Type Ib and Ic supernovae ・ Type II Cepheid ・ Type II collagen ・ Type II cytokine receptor ・ Type II hair keratin ・ Type II hypersensitivity ・ Type II keratin ・ Type II Partnerships ・ Type II secretion system ・ Type II sensory fiber ・ Type II site-specific deoxyribonuclease ・ Type II string theory ・ Type II supernova ・ Type II topoisomerase ・ Type III ・ Type III error ・ Type III hypersensitivity ・ Type III site-specific deoxyribonuclease ・ Type in ・ Type inference ・ Type inhabitation ・ Type introspection ・ Type IV collagen ・ Type IV collagen C4 domain ・ Type IV hypersensitivity ・ Type J1 submarine ・ Type K ・ Type L submarine Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Type II topoisomerase ： ウィキペディア英語版 Type II topoisomerase Type II topoisomerases cut both strands of the DNA helix simultaneously in order to manage DNA tangles and supercoils. They use the hydrolysis of ATP, unlike Type I topoisomerase. In this process, these enzymes change the linking number of circular DNA by ±2. ==Function== Once cut, the ends of the DNA are separated, and a second DNA duplex is passed through the break. Following passage, the cut DNA is religated. This reaction allows type II topoisomerases to increase or decrease the linking number of a DNA loop by 2 units, and it promotes chromosome disentanglement. Reactions involving the increase in supercoiling require two molecules of ATP. For example, DNA gyrase, a type II topoisomerase observed in ''E. coli'' and most other prokaryotes, introduces negative supercoils and decreases the linking number by 2. Gyrase is also able to remove knots from the bacterial chromosome. Along with gyrase, most prokaryotes also contain a second type IIA topoisomerase, termed topoisomerase IV. Gyrase and topoisomerase IV differ by their C-terminal domains, which is believed to dictate substrate specificity and functionality for these two enzymes. Footprinting indicates that gyrase, which forms a 140-base-pair footprint and wraps DNA, introduces negative supercoils, while topoisomerase IV, which forms a 28-base-pair footprint, does not wrap DNA. Eukaryotic type II topoisomerase cannot introduce supercoils; it can only relax them. The roles of type IIB topoisomerases are less understood. Unlike type IIA topoisomerases, type IIB topoisomerases cannot simplify DNA topology (see below), but they share several structural features with type IIA topoisomerases. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Type II topoisomerase」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.