L7 - De Novo Synthesis Of Pyrimidine Nucleotides Flashcards
1
Q
What is different in pyrimidine synthesis to purine?
A
Nucleic acid ring is assembled first
THEN attached to the ribose ring
2
Q
What is the enzyme that forms the ring?
A
Aspartate transcarbamylase
= allosteric anzyme
3
Q
What is an allosteric enzyme?
A
It has more than one active site
4
Q
What does aspartate transcarbamylase bind to?
A
Carbamoyl phosphate and aspartate
CTP (end product) inhibits further synthesis
= example of feedback control
5
Q
What molecules combine to form UMP?
A
Orotate + 5-phosphoribosyl-1-pyrophosphate (PRPP) which is then decarboxylated into Uridine monophosphate
6
Q
what does UMP change into?
A
uridine triphosphate (UTP)
7
Q
What does UTP convert into?
A
Cytidine triphosphate (CTP)
8
Q
A
