23530
Our previous high - speed AFM studies showed that mutation of tryptophan residue ( Trp40 ; W40 ) at the entrance of the catalytic tunnel drastically decreases the ability to degrade crystalline cellulose .
 Chemical: tryptophan; Chemical: Trp40
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: tryptophan; Chemical: Trp40