proteins

• proteins


  naturally occuring, unbranched polymer
• proteins


  most abundant substance in nearly all cells next to water
• Amino Acids


  monomers of proteins
• Elements that make up proteins


  C, H, O, N most also contain S
• Amino Acids


  building blocks for proteins
• serine, asparagine, threonine


  post translational modification of proteins
• cysteine


  active part of many enzymes; synthesis of CoA
• glutamine


  nitrogen carrier
• tyrosine


  precursor of : phenylalanine → tyrosine → levodopa → dopamine → norepinephrine → epinephrine (thyroid hormone melanin)
• glycine


  first steo of heme synthesis; inhibitory NTA in the SC, collagen
• alanine


  carrier of ammonia
• valine, leucine, isoleucine


  accumulate in maple syrup urine disease
• proline


  collagen
• phenylalanine


  precursor of tyrosine, accumulate in phenylketonuria
• methionine


  methyl group transfer
• tryptophan


  precursor of melatonin, serotonin, niacin
• aspartic acid


  participated in many metabolic pathways
• glutamic acid


  ionic form is an excitatory NTA; precursor of GABA
• histidine


  precursor of histamine
• lysine


  precursor of carnitine
• arginine


  precursor of creatinine & urea