14504
The interactions of these CpG sites with proteins are essential for recognition and catalysis and in many cases are characterized by the flipping of either of the cytosine bases out of the DNA helix .
 Chemical: CpG; Chemical: cytosine
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: CpG, cytosine 
Answer:
 Chemical: CpG; Chemical: cytosine