Where is nitrogen in the body obtained from?
What are the essential amino acids?
PVT TIM HALL
Which amino acid can be both essential and non essential?
When do Cysteine and tyrosine become essential?
if Methionine and Phenylalanin become limiting in the diet
what are sources of amino acids into the amino acid pool
tissue protein catabolism
Dietary protein from digestion
Synthesis of non essential AA's
What are 2 ways that AA's are utilized
Amino acid catabolism
SYthesis of nitrogen containing compounds
What are the two ways the protein is degraded? and what are the differences
lysosomal pathway- extracellular proteins
Ubiquitin pathway- endogenous proteins
What does ubiquitination mark the protein for?
destruction by the proteasome
What is the PEST sequence and what is it's effect
Proteins rich in Proline, Glutamate, Serine, and Threonine
short half life. die quickly
What is the process of ubiquitination dependant on?
What is the polyubiquitinated protein recognized and cleaved by?
What type of lysosomal enzymes are used to degrade protein
Where do most of the amino acids groups release their amino groups? and what do they release it as
What is Ammonia detoxified to and how
Urea via the Urea cycle
What is the major end product in Nitrogen metabolism
What are amino acid carbon skeletons used for?
What AA is formed from ammonia and by what enzyme
What is the major compound excreted in the urine
What other products are excreted in the urine
How do amino acids enter brush borders
through sodium potassium pump
What is cystinuria caused by?
decrease in cystine reabsorption due to deficiency of the cystine transporter.
What does the decrease in cystine absorption cause?
What other AA's are not absorbed properly in cystinuria
What is Hartnup's disease caused by?
defect in the transport of tryptophan
What are the symptoms of trytophan deficiency
What is the cause of pellegra
niacin is not synthesized from tryptophan in sufficient amounts
What are glucogenic AA's
catabolism yeilds pyruvate or an intermediate of the citric acid cycle
What are ketogenic AA's
yields acetoacetate, acetyl CoA or acetoacetyl CoA
Which of the previous two types of AA's are substrates for gluconeogenesis
What 4 AA's make pyruvate
What 3 AA's make acetyl CoA
What 5 AA's make acetoacetyl CoA
Which of the previous AA's are purely ketogenic?
What 2 AA's make Alpha Keto Glutarate
What 3 AA's make glutamate and glutamine
What 4 AA's make succinyl CoA
What two AA's make OAA
What 2AA's make Fumarate
What is the action of ALT?
Alanine to Pyruvate
What vitamin is needed for the ALT reaction and what are the coenzymes?
Pyridoxal Phosphate (B6)
Alpha KG to Glutamate
Is Transamination a reversible reaction?
Where is the glucose alanine cycle? what occurs at each site
muscle- where alanine is formed
Liver- site of gluconeogenesis
What metabolic process changes requires alanine? and under when is it most active?
What coverts glutamine to glutamate? and what is a byproduct
What converts Glutamate to A-KG
What coverts A-KG to Glutamate
What coverts Glutamate to Glutamine?
How many Nitrogens does glutamine, glutamate, and A-KG have?
Where is the glutaminase reaction performed?
Where is the Glutamine synthetase reaction performed
What is the non toxic transport form of ammonia from the peripheral tissues
How does asparaginase treat leukemia
decrease serum asparagine levels to starve the tumor
What is the effect of asparaginase
Asparagine to aspartate
What is the effect of Asparagine synthetase
Aspartate to Asparagine
What is the effect of AST?
Aspartate to OAA
What coenzyme does AST use?
Is AST a reversible step?