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Isishwankathelo
InkcazoViral protease loop.png
English: The C-terminal extension only present in viral members of the PA clan of chymotrypsin-like proteases as (a) surface with loop in blue (b) secondary structure and (c) b-factor putty (wider regions indicate greater flexibility) for the structure of TEV protease C151A (1lvb). Substrate in black, active site triad in red. The final 15 amino acids (222-236) of the enzyme C-terminus are not visible in the structure as they are too flexible.
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