Importance of pentose-5-phosphate | Ribose

Importance of pentose-5-phosphate

Pentose 5-phosphate plays a major role in the production of nucleotides, coenzymes and amino acids. Nucleotides are the basic building blocks of our genetic material, i.e. the DNA (carrier of our genetic code) and RNA (“building instructions” for various proteins etc.). Chemically speaking, a nucleotide consists of a phosphate part, sugar part and base part.

An important, relatively well-known nucleotide is ATP (adenosine triphosphate, energy carrier in the cells). Coenzymes are molecules that are essential for the function of certain enzymes. They bind to the respective enzyme and make it effective.

The coenzyme also changes during the chemical reaction of the enzyme and must then be restored to its original state. Only then can it “help” an enzyme again. Finally, ribose 5-phosphate is also indispensable for the synthesis of amino acids.

Amino acids are the basic building blocks of human proteins. They are not exclusively produced in the body, but must also be partially taken in with food (essential amino acids). This can be done through plant food (in cereals or legumes) or also through animal food (for example in muscle meat).

The human organism could not exist without amino acids. They are, so to speak, involved in all processes of the body. We consist of 20% proteins, which in turn are made up of amino acids. The concentration of proteins is particularly high in the muscles, bones and skin. In some cases, amino acids are also administered specifically in medicine to compensate for a possible deficiency.

Pentose phosphate cycle

Ribose 5-phosphate is produced by the so-called pentose phosphate cycle, which takes place in the cells of the human body. This biochemical process runs partly parallel to glycolysis. Glycolysis, in turn, is the metabolic pathway of glucose and is considered the first part of glucose metabolism.

Sooner or later, all carbohydrates and their chemical degradation pathways have to do with glycolysis. In the pentose phosphate cycle, NADPH (nicotinamide adenine dinucleotide phosphate) is also formed. This substance also plays an important role in the synthesis of fatty acids.

Therefore, the pentose phosphate cycle is particularly strong in tissues that require a lot of NADPH. These include liver cells, fat cells and the glandular cells of the female breast during lactation. The red blood cells also need the NADPH from the pentose phosphate cycle.

The tripeptide glutathione needs NADPH to provide a sufficient amount of hemoglobin.Hemoglobin, in turn, gives the red blood cells the ability to transport oxygen. If there is a lack of functioning enzymes for the pentose phosphate cycle, not enough NADPH can be produced and, among other things, the red blood cells (erythrocytes) are destroyed, a process known as hemolysis.