21651
The block polypeptides comprise proline - rich poly ( VPGXG ) and glycine - rich poly ( VGGVG ) , both of which dehydrate at higher temperature but form distinct secondary structures , beta - turn and beta - sheet respectively .
 Chemical: proline; Chemical: glycine
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: proline; Chemical: glycine