1950
Sequence analysis suggests that TtrA contains a molybdopterin guanine dinucleotide cofactor and a [ 4Fe - 4S ] cluster , that TtrB binds four [ 4Fe - 4S ] clusters , and that TtrC is an integral membrane protein containing a quinol oxidation site .
 GENE: TtrA; GENE: TtrB; GENE: TtrC
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: TtrA; GENE: TtrB; GENE: TtrC