11119
The outer membrane assembly platform - the usher - is critical for the formation of pili , catalysing the polymerisation of pilus subunits and enabling the secretion of the nascent pilus .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None