Review: Simmons Flashcards
What are amino acids broken into?
- Nitrogen - becomes urea
- Carbon skeletons - glucogenic and ketogenic
- Purines & Pyrimidines
What are the ketogenic carbon skeletons?
- AcCoA
2. Acetoacetate
What are the glucogenic carbon skeletons?
- Pyruvate
- alpha ketoglutarate
- Succinyl Co A
- Fumarate
- AOA
What are the source atoms for purine ring?
“TAGG”
- THF
- Asparpate
- Glycine
- Glutamine
Sources of atoms in pyrimidine ring?
“CAG”
- CO2
- Asparate
- Glutamine
Entry point to purine synthesis?
Ribose5P from pentose pathway
What is active form of ribose 5 phosphate?
PRPP
What is branch point for purine synthesis?
IMP - will become AMP or GMP
What is 6 mercaptopurine?
Anti tumor agent that blocks purine bionsynthesis
What is 5floro uracil?
- Anti tumor agent that targets Thymadilate synthase
- Blocks DNA synthesis specifically
What does methyl trexate do?
- Inhibits dihydroflourate reductase
- Preventing formation of THF
- Creates folate deficiency
- DHF levels rise which are toxic
What does dihydroflorate reductase do?
Enzyme that makes deoxy ribose
How are purines salavaged?
Hypoxanthine and guanine combined with PRPP to create creat nuclueotides: IMP & GMP
What is Lesch Nyhan syndrom?
- HGRTPase
- Self mutilation disease
What happens to purines that are not salvaged?
- Guanine and hypoxanthine are converted to xanthine
- Xanthine converted to uric acid
What causes gout?
Buildup up of Na urate cyrstale from purine degradation
What can excess uric acid cause?
Gout or kidney stones
How do you treat gout?
Alopurinol - blocks xanthine oxidase preventing formation of uric acid
What is heme made from ?
Succinyl CoA from CAC
Glycine
Control of heme pathway?
- Heme provides negative feedback
- As such if there is deficiency there will be no way for negative feedback increasing built up intermediates
First enzyme in heme pathway?
ALA synthase
What should you avoid with heme diseases?
The sun
What is globine degraded to?
AA
What is heme degraded to?
Biliverdin
