Biosynthesis of nucleotides Flashcards
(20 cards)
Important name in nucletoides? scientist..
John Buchanan
What is the difference between purines and pyrimidines?
Purine= 2 carbon nitrogen rings
pyrimidines: 1 carbon 1 nitrogen ring
What are the purines?
Adenine
Guanine
What are the pyrimidines?
Cytosine
Thymine
Uracil
What are the 2 pathways of nucleotide synthesis?
- De novo : using metabolic precursors (a.a. , ribose-5-phosphate, CO2, NH3)
- Salvage pathway: using purine and pyrimidines bases released from degration of nucleotides
What is the difference between nucleotide, nucleoside, and nitrogenous bases?
Nitrogenous bases: purine or pyrimidine
Nucleoside: pentose sugar + nitrogenous ring
Nucleotide: phosphate group: pentose sugar+ nitrogenous base
What is the bond between the nucleotides? Between what and what carbon?
Phosphodiester bond
Can purine and pyrimide be synthesized as independant molecules?
no! They are always part of a nucleotide
What are purines build on?
Ribose phosphate
What are pyrimidines build on?
OROTATE, and than attached to RIBOSE PHOSPHATe
What is one precursor but also intermediate in many pathways of a.a. and nucleotide synthesis?
5-phosphoribosyl 1-pyrophosphate (PRPP)
what is the a.a. precursor for purines?
GLycine
What is the a.a. precurosr for pyrimidines?
Aspartate
Aller voir les slides pour de novo synthesis of purines
GO
What type of inhibition is the regulation of novo synthesis of purines?
Feedback inhibition
What are the 2 phases in pentose phosphate pathway?
Oxidative and non-oxidative phase
What is the main enzyme that participate in the conversion of ribonucleotides to deoxyribonucleotides
Ribonucleotide reductase
Aller voir la page sur conversion de ribonucletodie to deoxyribonucleotide
GO
What does the non-oxidative phase of pentose phosphate pathway does?
It regenerates G-6-P from ribulose-5-phosphate
What does PRPP do in novo synthesis of purines and pyrimidines?
It brings in the ribose!
