7426
DNA topoisomerases comprise an important family of enzymes that catalyse the induction of topological changes ( e . g . relaxation / supercoiling , catenation / decatenation and knotting / unknotting ) in the DNA molecule .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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