Hyperthermophilic archaea possess an unusual gyrase called ________, which introduces positive supercoils into the chromosome in order to protect the DNA from ________.
A) reverse DNA gyrase; thermal denaturation
B) DNA helicase; thermal denaturation
C) topoisomerase I; gene overexpression
D) DNA ligase; thermal denaturation
E) reverse transcriptase; gene overexpression

Question

Quizplus · Accepted Answer

Hyperthermophilic archaea, which live in extremely high temperatures, possess a reverse DNA gyrase that introduces positive supercoils into the chromosome to protect the DNA from thermal denaturation. Option B is incorrect because DNA helicase is not a gyrase and does not introduce supercoiling. Option C is incorrect because topoisomerase I does not introduce positive supercoils. Option D is incorrect because DNA ligase is not a gyrase and does not introduce supercoiling. Option E is incorrect because reverse transcriptase is not a gyrase and does not introduce supercoiling.

Hyperthermophilic Archaea Possess an Unusual Gyrase Called ________, Which Introduces