Tryptophan (symbol Trp or W) is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a non-polar aromatic amino acid. It is essential in humans, meaning that the body cannot synthesize it and it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. It is encoded by the codon UGG.
Like other amino acids, tryptophan is a zwitterion at physiological pH where the amino group is protonated (–NH3; pKa= 9.39) and the carboxylic acid is deprotonated ( –COO; pKa= 2.38).
Tryptophan food source, egg white (10mg/g), spirulina (9.3mg/g), sesame seed (3.7mg/g), cheese (3.2mg/g), sunflower seeds (3.0mg/g), turkey (2.4mg/g), chicken (2.4mg/g), oats (2.3mg/g), beef (2.3mg/g), salmon (2.2mg/g), egg (1.7mg/g), poultry, chickpeas (1.9mg/g), milk (0.8mg/g), bananas (0.1mg/g), chocolate (13.3ug/g), peanuts, almond, rice, quinoa, potatoes, dried dates, yogurt etc Minimum daily intake for tryptophan is 4mg per kg (or 2.2lbs) body weight.
Periostin (POSTN, PN, or osteoblast-specific factor OSF-2) is a protein that in humans is encoded by the POSTN gene. Periostin functions as a ligand for alpha-V/beta-3 and alpha-V/beta-5 integrins to support adhesion and migration of epithelial cells. Periostin is a gla domain vitamin K dependent factor. Related Articles Food Healing Science - AZSP Healing reference reference