3524
In this process it binds four protons from the inner aqueous phase to make two water molecules , and translocates another four protons across the membrane , increasing the transmembrane difference of proton electrochemical potential which the ATP synthase then uses to synthesize ATP .
 ATP
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 ATP