MetaCyc Enzyme: methylglyoxal reductase (NADPH-dependent)

Species: Escherichia coli K-12 substr. MG1655

Methylglyoxal reductase catalyzes the conversion of methylglyoxal into lactaldehyde. The lactaldehyde is then acted upon by lactaldehyde dehydrogenase yielding lactate. This provides an alternate route for methylglyoxal metabolism [Saikusa87]. No gene has been identified for this enzyme.

Molecular Weight of Polypeptide: 43.0 kD (experimental) [Saikusa87]

Gene-Reaction Schematic

Gene-Reaction Schematic

Imported from EcoCyc 30-Sep-2015 by Paley S, SRI International

Enzymatic reaction of: methylglyoxal reductase (NADPH-dependent)

Inferred from experiment

EC Number:

(S)-lactaldehyde + NADP+ ← methylglyoxal + NADPH + H+

The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the Enzyme Commission system.

The reaction is favored in the opposite direction.

Alternative Substrates for methylglyoxal [Saikusa87]: glycolaldehyde [Saikusa87], acetaldehyde [Saikusa87], propanal [Saikusa87], DL-glyceraldehyde [Saikusa87], 4,5-dioxopentanoate [Saikusa87], phenylglyoxal [Saikusa87], glyoxal [Saikusa87]
Alternative Substrates for NADPH [Saikusa87]: NADH

In Pathways: superpathway of methylglyoxal degradation, methylglyoxal degradation IV

Imported from EcoCyc 30-Sep-2015 by Paley S, SRI International

The enzyme was purified from E. coli IFO 3806 [Saikusa87].

Activators (Unknown Mechanism): glutathione [Saikusa87], L-dithiothreitol [Saikusa87], 2-mercaptoethanol [Saikusa87] Inhibitors (Unknown Mechanism): Cu2+ [Saikusa87], Zn2+ [Saikusa87], Ni2+ [Saikusa87], Co2+ [Saikusa87], p-chloromercuribenzoate [Saikusa87]

Primary Physiological Regulators of Enzyme Activity: Cu2+, Zn2+, Ni2+, Co2+

Kinetic Parameters:
Substrate Km (μM) Citations
methylglyoxal 4000.0 [Saikusa87]
NADPH 1.7 [Saikusa87]

T(opt): 45 °C [Saikusa87]

pH(opt): 6.5 [Saikusa87]


Saikusa87: Saikusa T, Rhee H, Watanabe K, Murata K, Kimura A (1987). "Metabolism of 2-oxoaldehydes in bacteria: purification and characterization of methylglyoxal reductase from E. coli." Agricultural and Biological Chemistry 51(7): 1893-1899.

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Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 19.5 on Wed Nov 25, 2015, BIOCYC14A.