26303
C101 , in contrast , is S - nitrosated in a single step but is subject to negative cooperativity due to steric hindrance at the dimer interface .
 Chemical: S
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: S 
Answer:
 Chemical: S