Human Lactate Dehydrogenase

Lactate dehydrogenase (LDH) is a main component of anaerobic respiration within the human body. This molecule come into play when there is a lack of oxygen, such as during intense exercise. Anaerobic respiration is defined as respiration without the involvement of oxygen. Anaerobic respiration is used during intense exercises or other strenuous activities, when one is lacking available oxygen. LDH is mainly found in the heart, liver, kidney, and muscles of the body; each with a slightly different composition. Lactate dehydrogenase is a quaternary structureis composed of two main subunits, H and M (heart and muscle).Based on the different reactions the two subunits preform, different combinations can be found throughout the body.

Structure

Lactate dehydrogenase is composed of quaternary structure and can be found in humans. It has two main subunits, H and M (heart and muscle). The H form converts pyruvate to lactate, while the M form converts lactate back to pyruvate. Based on the different reactions the two subunits preform, different combinations can be found throughout the body. is found in the heart, is found in the reticuloendothelial (part of the immune system), 2H2M is found in the lungs, 1H3M is found in the kidneys, and 4M is found in the muscles and liver.

Function

Lactate dehydrogenase is a main component of anaerobic respiration within the human body. This molecule come into play when there is a lack of oxygen, such as during intense exercise. During intense exercise our body requires a larger amount of oxygen, and glycolysis becomes our main source of energy. In order for glycolysis to work smoothly and avoid access NADH, we need available oxygen. This is where LD (lactase dehydrogenase) comes into play. LDH converts pyruvate into lactate, giving our body more ATP. When we halt the exercise and take a deep breath LDH converts the lactate back to pyruvate, and we continue on our normal aerobic pathway of glycolysis.

Relevance

Lactate Dehydrogenase allows humans to perform strenuous exercises for a longer length of time. Without LDH, humans would not have an adequate amount of ATP to sucessfully perform intense exercises such as running, biking, etc. LDH allows our bodies to convert pyruvate into something that our body can utilize (lactate) to produce ATP when oxygen is unavailable.