Reverse gyrase - Wikipedia
Reverse gyrase is a type I topoisomerase that introduces positive supercoils into DNA, [1] contrary to the typical negative supercoils introduced by the type II topoisomerase DNA gyrase. These positive supercoils can be introduced to DNA …
DNA回旋酶 - 百度百科
DNA负超螺旋的引入能使打断 碱基对 所需的能量降低约4.1kJ mol-1，有利于将 DNA双链 分开。 在复制过程中，当DNA新链在 模板 上形成后，DNA回旋酶将复制好的DNA双链变为天然的 负超螺旋 的构型，此过程需 ATP水解 供能。
Reverse gyrase—recent advances and current mechanistic …
2014年9月1日 · Reverse gyrases are topoisomerases that introduce positive supercoils into DNA in an ATP-dependent reaction. They consist of a helicase domain and a topoisomerase domain that closely cooperate in catalysis. The mechanism of the functional cooperation of these domains has remained elusive.
DNA gyrase - Wikipedia
DNA gyrase, or simply gyrase, is an enzyme within the class of topoisomerase and is a subclass of Type II topoisomerases [1] that reduces topological strain in an ATP dependent manner while double-stranded DNA is being unwound by elongating RNA-polymerase [2] or by helicase in front of the progressing replication fork.
Reverse Gyrase Functions as a DNA Renaturase - Journal of …
Reverse gyrase is a hyperthermophile-specific enzyme that can positively supercoil DNA concomitant with ATP hydrolysis. However, the DNA supercoiling activity is inefficient and requires an excess amount of enzyme relative to DNA. We report here several activities that reverse gyrase can efficiently mediate with a substoichiometric amount of ...
Reverse gyrase: an insight into the role of DNA-topoisomerases
In addition to new biochemical properties, a fine tuning of reverse gyrase regulation in response to DNA damaging agents has been recently described. These data give us a new insight in the cellular role of reverse gyrase.
Direct observation of DNA overwinding by reverse gyrase - PMC
Reverse gyrase, found in hyperthermophiles, is the only enzyme known to overwind (introduce positive supercoils into) DNA. The ATP-dependent activity, detected at >70 °C, has so far been studied solely by gel electrophoresis; thus, the reaction dynamics remain obscure.
Reverse gyrase: An insight into the role of DNA-topoisomerases
2007年4月1日 · Hence, reverse gyrase has an important role in genome reactivity by introducing positive supercoils in DNA, by annealing complementary single-stranded DNA and by acting as a DNA chaperone. All these activities contribute to preserve the double helical structure and act as a guardian of B-DNA.
Evolution of Reverse Gyrase Suggests a Nonhyperthermophilic …
2019年9月3日 · Reverse gyrase (RG) is the only protein found ubiquitously in hyperthermophilic organisms, but absent from mesophiles. As such, its simple presence or absence allows us to deduce information about the optimal growth temperature of long-extinct organisms, even as far as the last universal common ancestor of extant life (LUCA).
Direct observation of helicase–topoisomerase coupling within reverse gyrase
2020年5月5日 · Uniquely, hyperthermophiles have fused these functional units into a chimeric enzyme known as reverse gyrase (RG), which is capable of positively supercoiling DNA using ATP hydrolysis. Single-molecule experimentation allows us to observe at single-molecule resolution the helicase–topoisomerase coupling in RG that leads to the catalytic ...