Natural Chemicals
Serine
Category: Natural chemicals
Type
Voluntary
Introduction and description
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Serine (symbol Ser or S) is an ɑ-amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. Pure D-serine is an off-white crystalline powder with a very faint musty aroma. D-Serine is sweet with an additional minor sour taste at medium and high concentrations. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC.
Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, sericum. Serine's structure was established in 1902.
Uses
Serine is important in metabolism in that it participates in the biosynthesis of purines and pyrimidines. It is the precursor to several amino acids including glycine and cysteine, as well as tryptophan in bacteria. It is also the precursor to numerous other metabolites, including sphingolipids and folate.
Serine also plays an important role in the catalytic function of many enzymes. It has been shown to occur in the active sites of chymotrypsin, trypsin, and many other enzymes. The so-called nerve gases and many substances used in insecticides have been shown to act by combining with a residue of serine in the active site of acetylcholine esterase, inhibiting the enzyme completely.
Serine deficiency disorders
Serine deficiency disorders are rare defects in the biosynthesis of the amino acid L-serine. At present three disorders have been reported:
· 3-phosphoglycerate dehydrogenase deficiency,
· 3-phosphoserine phosphatase deficiency and
· Phosphoserine aminotransferase deficiency.
These enzyme defects lead to severe neurological symptoms such as congenital microcephaly and severe psychomotor retardation and in addition in patients with 3-phosphoglycerate dehydrogenase deficiency to intractable seizures.
These symptoms respond to a variable degree to treatment with L-serine, sometimes combined with glycine. Response to treatment is variable and the long-term and functional outcome is unknown. To provide a basis for improving the understanding of the epidemiology, genotype/phenotype correlation and outcome of these diseases their impact on the quality of life of patients, as well as for evaluating diagnostic and therapeutic strategies a patient registry was established by the non-commercial International Working Group on Neurotransmitter Related Disorders (iNTD).