lecture 31 - amino acids as fuel molecules Flashcards
what is the deamination of amino acids
removal of the nitrogen group from amino acid
what does deamination of amino acids generate and what occurs to them
carbon skeleton = can be used for energy capture
a free amino acid = generally excreted
what are the two ways to deaminate an amino acid
- releasing their amino acid groups to solution
- transferring their amino acid group to a keto acid
what is the transferring of amino acid to keto acid catalysed by
aminotransferase enzymes (transmainases)
- requires co enzyme
what is transferring amino acid group to keto acid called (deamination)
transamination
how is an amino acid deaminated by releasing amino group to solution
enzyme catalysed reaction where amino groups is chopped off and released to solution
what is the co enzyme required for transamination reactions and what does it do
pyridoxal phosphate (PLP) = carries amino acid group from amino acid to keto acid
what forms does the co enzyme that is required for transamination reactions exist in
pyridoxal phosphate (no amino acid) and pyridoxamine phosphate (with amino group)
what is the first step of transamination
amino group is transferred from the amino acid to the pyridoxal phosphate (becomes pyridoxamine phosphate)
what is the second step of transamination
amino group is transferred from pyridoxamine phosphate (becomes pyridoxal phosphate) to the keto acid
what is the keto acid of aspartate
oxaloacetate
what is the keto acid of alanine
pyruvate
what is the keto acid of glutamate
a-ketoglutarate
can all keto acids be feed into metabolic pathways
some can directly enter and some require modification first
how is excess nitrogen removed from the body
via the liver = also requires transamination reactions
