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By combining our structure with previously solved KIF1A structures complexed with two ATP analogs , molecular snapshots during ATP binding reveal that the closure of the nucleotide - binding pocket during ATP binding is achieved by closure of the backdoor .
 Chemical: ATP; Chemical: ATP; Chemical: nucleotide; Chemical: ATP
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: ATP; Chemical: ATP; Chemical: nucleotide; Chemical: ATP