Biosynthesis and Degradation Flashcards
Differentiate between the De novo and salvage pathways
De novo - means from the new - taking basic precursors to assemble a brand-new molecule. It is a longer pathway and is more complicated.
Salvage - taking premade/salvaged molecules to assemble a new molecule
What are the parent purine nucleotides of nucleic acids?
Adenosine-5’-monophosphate (AMP)
Guanosine-5’-monophosphate (GMP)
Describe a general De novo pathway.
taking basic precursors to assemble a brand-new molecule
Where does De novo purine nucleotide biosynthesis begin?
The molecule phosphoribosyl pyrophosphate (PRPP)
What happens in the first step of purine nucleotide biosynthesis?
An amino group is donated by glutamate and this group is then attached to carbon #1 of PRPP
What results from the first step of purine nucleotide biosynthesis?
5-phosphoribosyl amine
5’-phosphoribosyl amine is extremely _______ with a half life of _______ at __________
Unstable
30 seconds
At pH of 7.5
What structure is the purine ring built upon?
5’-phosphoribosyl amine
What parts come together to formthe first purine ring?
Aspartate
CO2
Glycine
Formate
Amine nitrogen of glutamine
Draw the structure of the first purine ring.
Where does the nitrogen on the left come from?
Asparate
Draw the structure of the first purine ring.
Where does the carbon at the of the left ring come from?
CO2
Draw the structure of the first purine ring.
Where do the two nitrogens at the base originate?
Amide nitrogen of glutamine
Draw the structure of the first purine ring.
Where do the bottom carbons (one in each ring) come form?
Formate
Draw the structure of the first purine ring.
What molecules come from glycine?
The carbons in the bridge and the top nitrogen in the five-members ring
What is the first intermediate in the De novo purine pathway to have a complete purine ring?
Insinate (IMP)
