= Solution
\b[An ionizable Asp296 carboxyl group is not essential to the measured catalytic pathway at pH 7.] <Asparagine> retains a similar side-chain size and an amide donor/acceptor pair, while losing the carboxyl group's ordinary acid/base chemistry and negative charge. Preserved kinetics are therefore consistent with a binding or positioning <hydrogen bond> that survives the conservative substitution, or with a dispensable/redundant contact.
This does not prove that Asp296 makes no interaction in the native <enzyme>, nor that every substitution at that position would be harmless. The displayed Asp296 contact is also distinct from Asp295, which coordinates zinc; their neighboring residue numbers must not be conflated. Other pH values could expose a contribution hidden by the assay condition.
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