| Cat# | NATE-1008 |
| Descriptions | Stable microbial Lactate Dehydrogenase catalyzes reversible redox reactions between lactate and pyruvate, enabling quantitative measurement of lactate concentration in plasma, serum and tissue fluid samples. This diagnostic enzyme is essential for evaluating tissue hypoxia, myocardial injury and metabolic acidosis, supporting routine emergency and internal medicine biochemical diagnostic testing projects. |
| Applications | This product can be coupled with relevant enzymes in clinical diagnosis to measure various metabolites like ATP, ADP, glucose, creatinine, pyruvate, lactate and glycerol, as well as enzyme activities including GPT, PK and CPK. |
| Synonyms | (R)-Lactate: NAD⁺ oxidoreductase |
| EC Number | EC 1.1.1.28 |
| Catalysis | D-Lactate + NAD⁺ + H₂O ⇆ Pyruvate + NADH + H⁺ |
| Activity | ≥ 100 U/mg (Lactate dehydrogenase activity) |
| Contaminant | ≤ 1 × 10⁻⁴% (NADH oxidase activity); ≤ 3 × 10⁻⁴% (α-KGDH activity); ≤ 5 × 10⁻⁴% (GOT activity); ≤ 5 × 10⁻⁴% (GPT activity) |
| Appearance | White powder, lyophilized |
| Additive | Dextran |
| Molecular Weight | 64,000 (Gel filtration) |
| Isoelectric Point | 4.3 |
| Km | 6.7 × 10⁻⁴ M (Pyruvate); 7.6 × 10⁻⁴ M (NADH) |
| Optimum pH | 5.0 |
| pH Stability | 5.5-8.5 (30°C, 1 h) |
| Optimum Temperature | 40°C |
| Thermal Stability | up to 35°C (pH 7.0, 1 h) |
| Unit Definition | 1 unit is defined as the enzyme quantity which oxidizes 1 μmol of NADH per minute under the conditions described below. |
| Storage | 24 months from the date of analysis when stored at -20°C or below in a dry place under sealed conditions. |
1 unit is defined as the enzyme quantity which oxidizes 1 μmol of NADH per minute under the conditions described below.
Pipette 2.9 mL of Substrate solution (C) into a quartz cell (d=10 mm) and keep at 25±0.5 ℃ for 5 minutes. Then, pipette 0.1 mL of Enzyme solution (D) into the quartz cell and mix well immediately. Keep the reaction mixture at 25±0.5 ℃. Exactly at 2 minutes and 5 minutes after the addition of Enzyme Solution (D), measure the absorbances of the reaction mixture at 340 nm. (A2 and A5). As a blank, pipette 0.01M Phosphate buffer (B) into another quartz cell (d=10 mm) instead of Enzyme Solution (D), and take the same procedure described above. (Ab2 and Ab5)
