Enzyme
1.1.1.27 - L-lactate dehydrogenase
Alternative Name(s)
- L-lactic acid dehydrogenase.
- L-lactic dehydrogenase.
Catalytic Activity
(S)-lactate + NAD(+) = H(+) + NADH + pyruvate
Cofactors
There are no Cofactors for this Enzyme
Reaction Mechanism
Lactate dehydrogenase catalyses the interconversion of L-lactate and pyruvate in the glycolytic pathway, coupled with the reduction/oxidation of NAD+ and NADH. The enzyme crystallised from dogfish is a homotetramer. There has been some debate about whether the enzyme mechanism is concerted or stepwise.
In the forward direction a proton is abstracted from lactate and a hydride donated to NAD+. In the reverse direction a proton is donated to pyruvate and a hydride ion donated from NADH. The proton donor/abstractor depending on direction is His193, which is regulated via hydrogen-bond to Asp166. The hydride is donated/abstracted by NADH/NAD+. It is likely that the reaction proceeds in a stepwise manner with Arg169 stabilising the charge via a strong salt bridge to the substrate, and possibly via electrostatic interactions from Arg106.
Catalytic Residues
| AA | Uniprot | Uniprot Resid | PDB | PDB Resid |
|---|---|---|---|---|
| His | P00341 | 194 | 1ldm | 193 |
| Arg | P00341 | 107 | 1ldm | 106 |
| Arg | P00341 | 170 | 1ldm | 169 |
| Asp | P00341 | 167 | 1ldm | 166 |
Step Components
overall reactant used, proton transfer, overall product formed, native state of enzyme regenerated, inferred reaction step, cofactor used, hydride transfer
Step 1.
His193 abstracts a proton from the hydroxyl group of the substrate. NAD accepts a hydride in a nucleophilic addition reaction.
Step 2.
In an inferred step his193 is deprotonated to regenerate the native state of the enzyme.
Products.
The products of the reaction.
Reaction Parameters
There are no kinetic parameters information for this Enzyme
Associated Proteins
Citations
- L-Lactate treatment by photosynthetic cyanobacteria expressing heterogeneous L-lactate dehydrogenase.
- Recombinant production, purification, and biochemical characterization of a novel L-lactate dehydrogenase from Bacillus cereus NRC1 and inhibition study of mangiferin.
- An Oxygen-Insensitive biosensor and a biofuel cell device based on FMN l-lactate dehydrogenase.
- Relationship between L-lactate dehydrogenase and multidrug resistance in Staphylococcus xylosus.
- A functionally uncharacterized type-2 malate/L-lactate dehydrogenase family protein from Thermus thermophilus HB8 catalyzes stereospecific reduction of 2-keto-3-deoxy-D-gluconate.
- Modified Catalytic Performance of Lactobacillus Fermentum L-lactate Dehydrogenase by Rational Design
- Enantioselective Biosynthesis of L-Phenyllactic Acid From Phenylpyruvic Acid In Vitro by L-Lactate Dehydrogenase Coupling With Glucose Dehydrogenase.
- Effects of freezing rate on structural changes in L-lactate dehydrogenase during the freezing process.
- Characterization of a Novel Thermostable Dye-Linked l-Lactate Dehydrogenase Complex and Its Application in Electrochemical Detection.
- Lactate metabolism in strictly anaerobic microorganisms with a soluble NAD+ -dependent l-lactate dehydrogenase.
- Cloning and characterization of a L-lactate dehydrogenase gene from Ruminococcaceae bacterium CPB6.