2891
The mutated glutamine is not only highly conserved in evolution ( conserved also in Escherichia coli and Saccharomyces cerevisiae ) , but is also two amino acid residues downstream from the active site histidine - proline - histidine triad and results in about 10 % of normal enzymatic activity .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease 
Text: {0} 
Answer:
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