Protein Metabolism Flashcards
Exopeptidase vs. endopeptidase
exo: attacks C or N-terminus ends
endo: attacks withing specific site, digests internal pep. bonds
the “kitchen disposal” for proteins, that utilizes ubiquinin as a marker for degradation
Proteasomal degradation
sucks protein in, shreds it to peptide fragments
Proteolytic enzyme are ____, because they are inactive until the body relases another enzyme____ to activate it. For example Trypsinogen
inactive zymogens
enterokinase
It turns from chymotrypsinogen to chymotrypsin
or trypsinogen to trypsin
both activated my enterokinase
Conditionally essential AA’s?
essential?
Arginine and glutamine PVT TIM Hall Phe Val Trp Thr Isoleucine Methionine Histdidine Arg Lys Leu
Branching AAs
Ile
Leu
Val
Name a transaminase enzyme that’s a derivative of B6?
Other ones?
Pyridoxyl 5’ Phosphate (PLP)
Alanine transaminase(ALT) Aspartate transaminase (AST)
alpha ketoglutarate is made from what? what is this important for?
Glu (glutamate) which is made from Gln, His, Arg, Pro
Product of Isocitrate in the TCA
Succinyl CoA is made from what AAs?
What is it important for?
Met, Thr, Ile, Leu, Val
TCA Cycle
Homocystinuria is a disease fromt eh break down of what aa?
Met
Affects:Eyes, skeleton, CNS, vascular
Homocystinuria is the defect in what enzyme?
What vit. are deficient?
cystathionine beta-sythase
B6, B12, Folic acid
B6 = Pyridoxal phosphate (PLP)**
Leu to ____ issue can cause Maple syrup urine dis.
Acetyl CoA
deficient in branched-chain alpha keto acid dehydrogenase complex (BCKD)
____ to Tyr to eventualy fumarate is the pathway PKU can arise from if ___ is defective.
Phe phenylalanine hydroxylase (PAH)
Phe turns to phenyllactate, phenyllactate and pheylacetate,
___ is a precursor of serotonin and melatonin.
Trp
If tyrosinase is deficient what diesease occurs?
Albinism, absence of pigmentation
what protein is the precursor of T3 and T4?
Thyroglobulin
What AA’s are removed from the rbain for overall Ammonia?
in other tissues?
Glu, Gln in brain
Gln, Ala in tissue
Ammonia vs. Ammonium
Ammonia = NH3
Ammonium ion = NH4+
___ to glutamate to glutamine —->bloodstrem to liver’s urea cycle for removal of excess NH4+ in BRAIN
alpha - ketoglutarate
GLu to ALa —>bloodstream to liver’s urea cycle
Ammonium removal from muscle
Where does the Urea Cycle occur?
Btwn teh mitochondria and the cytosol in teh liver
Two AA’s that don’t make protein, are only for precursors in the Urea Cycle
ornithine
citurlline
H20 + ____ = Urea
Where is Urea released?
Arg
in the cyytosol, gets sent via blood to kidney
3 AA’s that make Creatine?
“Always Growing Muscle”
Arg
Gly
Met
Quick form of atp for muscles, brain, sperm
phosphocreatine
In removing ammonium from the liver and muscle, what forms are they made as to be sent to the liver and go to the urea cycle?
Brain: sends Gln
Muscle: sends Ala
To make Alpha ketoglutarate ?
Glu
To make Glu
“His Gluts Are Plump” His Gln Arg Pro
What AA makes just Acetyl CoA? Why?
Leu
It’s ketogenic
Lys makes only acetoacetate
What makes fumarate? Diseases with this pathway?
Phe
To
Tyr
Alkaltonuria, defective homogentisate oxidase
What makes oxyloacetate?
Where else is oxyo. Important?
Asn to asp
Fa synth
Trp makes what? What vitamin does it need to do it
What disease with this path
Serotonin then melatonin
Trp in TURKEY so you get SLEEPY
Needs B6
Carcinoid Tumor
Tyr makes what?
What diseases
T3, T4 graves and hypo/hyperthyroidism
(T3 (triiodthryonin), T4 (Thyroxine) )
Melatonin, albinism
dopamine, Parkinson’s
Norepinephrine
Epinephrine
Ammonia isn’t charge so why is it more toxic than ammonium ion?
NH3
Can travel across biological membranes
