However, these conditions are so vigorous that some amino acids (serine, threonine, tyrosine, tryptophan, glutamine, and cystine) are degraded.
en.wikipedia.org The glycogen phosphorylase dimer has many regions of biological significance, including catalytic sites, glycogen binding sites, allosteric sites, and a reversibly phosphorylated serine residue.
en.wikipedia.org There are 89 predicted sites of serine phosphorylation, 17 predicted sites of threonine phosphorylation, and 11 predicted sites of tyrosine phosphorylation.
en.wikipedia.org Free trypsin is then able to activate other serine proteases, such as chymotrypsin, elastase, and more trypsin (by autocatalysis), or continue breaking down proteins.
en.wikipedia.org Serine proteases are paired with serine protease inhibitors, which turn off their activity when they are no longer needed.
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