pentoosifosfaatin

Pentoosifosfaatti, also known as pentose phosphate, refers to a group of phosphorylated pentose sugars. These molecules are crucial intermediates in various biochemical pathways, most notably the pentose phosphate pathway (PPP), also known as the hexose monophosphate shunt.

The primary function of the pentose phosphate pathway is to produce NADPH, a reducing agent essential for anabolic reactions and protecting cells against oxidative stress. NADPH is generated during the oxidative phase of the PPP, which converts glucose-6-phosphate into ribulose-5-phosphate. This process also produces carbon dioxide.

Another key output of the pentose phosphate pathway is ribose-5-phosphate. This five-carbon sugar is a precursor for the synthesis of nucleotides, which are the building blocks of DNA and RNA. Therefore, the PPP is vital for cell growth and division, as well as for the synthesis of nucleic acids.

The pentose phosphate pathway operates in the cytoplasm of cells and is particularly active in tissues with high rates of reductive biosynthesis, such as the liver, adipose tissue, and adrenal cortex, as well as in red blood cells where NADPH is critical for protecting hemoglobin from oxidation. The balance between the oxidative and non-oxidative branches of the pathway allows for the interconversion of various pentose phosphates and other sugars to meet cellular needs.