DL-threo-2-methylisocitrate sodium is a substrate of isocitratelyase 1(ICL1).
ICL1 had dual activity for both threo-D(s)L(s)-isocitrate (ICA) and DL-threo-2-methylisocitrate (MICA). Using Michaelis-Menten non-linear least squares fit, the Km of purified recombinant ICL1 for threo-D(s)L(s)-isocitrate (ICA) was determined to be 188 mM with akcatof 5.24 s-1 .The Km of ICL2 for MICA was greater than 15 mM which was too high to be determained accurately due to the limitations of the solubility of MICA. The Kcat/Km for ICL1, a measureforcatalyticefficiency, was 2.79 × 104 M-1 s-1 and 1.74 ×103 M-1 s-1, for ICA and MICA respectively.
Reference:
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