21169
The observed signal intensities in BSI are greater for each fragment upon binding to apo - PR than to pepstatin - bound PR , consistent with greater conformational change in the former binding event .
 Chemical: pepstatin
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: pepstatin