169800
A short open reading frame is found within the motif that encodes at least two tryptophan codon s. Similar motifs have been identified regulating tryptophan genes in proteobacteria ( see trp operon ) , but not in Bacteroidetes .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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