18739
Compared with other beta - N - acetylhexosaminidases , lacto - N - biosidase has a wide substrate - binding pocket with a - 2 subsite specific for beta - 1 , 3 - linked Gal , and the residues responsible for Gal recognition were identified .
 Chemical: N; Chemical: N; Chemical: Gal; Chemical: Gal
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: N; Chemical: N; Chemical: Gal; Chemical: Gal