4.1.2.40 K124A strongly reduced aldolase activity 679492 4.1.2.40 K204A mutation results in more than 98% decrease in aldolase activity 679492 4.1.2.40 L165E the mutant shows enhanced substrate specificity toward fructose-1,6-bisphosphate 715040 4.1.2.40 L165E/L275S the mutant shows enhanced substrate specificity toward fructose-1,6-bisphosphate 715040 4.1.2.40 L275S the mutant shows enhanced substrate specificity toward fructose-1,6-bisphosphate 715040 4.1.2.40 additional information construction of chimeras of isoforms LacD.1 and LacD.2. The C-terminus of LacD.1 contributes to its differential enzymatic activity, as replacing of its C-terminal half with 162 amino acid residues from the C-terminus of LacD.2 leads to an enzyme very similarly to LacD.2 in the cleavage of tagatose bisphosphate but over 3 times more efficient than LacD.2 at cleaving fructose bisphosphate. In addition, loop 1 and turn 2 influence the differential enzymatic activity of LacD.1 -, 727768