Amino Acid Metabolism Flashcards
Negative Nitrogen Balance
Dietary Def. of any one of the essential AAs
Extreme conditions of DM
Pathogenic infections; general STARVATION
Positive Nitrogen Balance
Fetal Development (Pregnancy)
Human Development (Growth)
Post Injury or Surgery (Recovery Phase)
Recovery from Fasting/Starvation
Deficiency of selective amino acids
Kwashiorkor
Severe nutritional deficiency (including proteins, fats, and carbs)
Marasmus
Kwashiorkor Effects
less serum albumin synthesis, causing osmotic imbalance in the blood and generalized edema
Compare Sx of Kwashiorkor and Marasmus
Kwashiorkor: generalized Edema, protuberant belly, itchy rash, xerosis, poor wound healing
Marasmus: prominent bones, decreased subQ fat, loose skin
Essential Amino Acids
Phenylalanine Valine Threonine Tryptophan Isoleucine Methionine Histidine Arginine (semi-essential) Leucine Lysine
Ketogenic amino acids
leucine and lysine
produce only acetyl CoA or acetoacetyl CoA
Coenzyme in Transamination Reaction
Pyridoxal Phosphate (Vitamin B6)
Transamination Rxn Substrates
Pyruvate to Alanine
OAA to Aspartic Acid
Alpha Keto-Glutarate to Glutamate
Diagnostic Markers for Liver Cell Damage
AST (Aspartate Transaminase) and ALT (alanine transaminase)
NH3
Ammonia. Toxic because it can pick up a proton from the blood (–> ammonium NH4) increasing the blood pH (Alkalosis)
Glutamine Cycle
glutamate + NH4 + ATP —-> Glutamine + ADP +Pi
end: glutamine synthetase
How is Nitrogen transported?
glutamine (NOT ammonia because it’s toxic)
Glutaminase
In the Liver
Converts glutamine into glutamate and ammonia
ammonia can then enter urea cycle
