16289
Using a kinetic , optical assay of F1 . epsilon binding and dissociation , we show that formation of the extended , inhibitory conformation of epsilon ( epsilon X ) initiates after ATP hydrolysis at the catalytic dwell step .
 ATP
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 ATP