Serine:

• Encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC) is a ɑ-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH+3 form under biological conditions), a carboxyl group (which is in the deprotonated –COO−form in physiological conditions), and a side chain consisting of a hydroxymethyl group (see hydroxyl), classifying it as a polar amino acid.
• It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid.
• Serine provides the carbon skeleton and homocysteine the sulfur for cysteine biosynthesis.
• serine provides carbons 2 and 8 of purines and the methyl group of thymine.

Serine (Low):

• Issues with falling to sleep. (yack)

Make NADPH and Glutathione:

• Vitamin B-6 and the amino acid L-serine participate in the activation of the sulfuration pathway. Hence B-6’s importance in glutathione formation. B-6 also is critical to activate the gamma-glutamyl cycle (via the GGT enzyme), a pathway that brings cysteine, glycine, and glutamine together in the cytoplasm of cells to form glutathione.