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CENTRAL CARBON → 3-PHOSPHOGLYCERATE FAMILY → INDIVIDUAL PATHWAY

Serine biosynthesis

Follow the carbon skeleton from 3-Phosphoglycerate to L-Serine.

What it needs

3-Phosphoglycerate from central metabolism, glutamate and NAD⁺.

What it supplies

L-Serine. This product can enter downstream cellular reactions; its synthesis depends on the precursor and helper supplies shown.

The pathway

Read from top to bottom. Select an enzyme box to jump to its reaction. Cosubstrates and selected coproducts appear in the account below.

Serine biosynthesis3-Phosphoglycerate to 3-Phosphohydroxypyruvate via Phosphoglycerate dehydrogenase; 3-Phosphohydroxypyruvate to O-Phospho-L-serine via Phosphoserine aminotransferase; O-Phospho-L-serine to L-Serine via Phosphoserine phosphatase3-Phosphoglycerate1. Phosphoglycerate dehydrogenaseNAD⁺ → NADHRead reaction 13-Phosphohydroxypyruvate2. Phosphoserine aminotransferaseGlutamate → 2-oxoglutarate; PLP-dependentRead reaction 2O-Phospho-L-serine3. Phosphoserine phosphataseWater consumed; phosphate releasedRead reaction 3L-Serine

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Reactions and enzymes

1 · Phosphoglycerate dehydrogenase

3-Phosphoglycerate → 3-Phosphohydroxypyruvate

Phosphoglycerate dehydrogenase · EC 1.1.1.95

Inputs, helpers or coproducts: NAD⁺ → NADH

2 · Phosphoserine aminotransferase

3-Phosphohydroxypyruvate → O-Phospho-L-serine

Phosphoserine aminotransferase · EC 2.6.1.52

Inputs, helpers or coproducts: Glutamate → 2-oxoglutarate; PLP-dependent

3 · Phosphoserine phosphatase

O-Phospho-L-serine → L-Serine

Phosphoserine phosphatase · EC 3.1.3.3

Inputs, helpers or coproducts: Water consumed; phosphate released

Connected pathways

Glycine from serineCysteine biosynthesisTryptophan biosynthesis

Evidence and scope

This is the phosphorylated serine pathway. Serine also connects to glycine and one-carbon metabolism. This page explains selected documented biochemical reactions. It does not establish that every displayed enzyme occurs in Aquifex, that the pathway is universally essential, or that the book image records a complete organism. Gene symbols name common enzyme activities; organism-specific protein records require separate matching.

Original explanatory diagram and reaction account, based on the records below. Arrows show the biosynthetic reading direction; they do not claim that every reaction is irreversible. Selected protons, water and cofactors are omitted from the overview and are not implied absent.

Compare the related Aquifex annotation group →