Nucleotides and Nucleic Acids Flashcards
what is a purine
guanine and adenine for both DNA and RNA
what is a pyrimidine
thymine and cytosine for DNA
uracil and cytosine for RNA
what is a nucleoside
base + sugar
what is a nucleotide
base + sugar + phosphate
name the free base and nucleotide of the nucleoside Adenosine
adenine
AMP-ADP-ATP-cAMP
name the free base and nucleotide of the nucleoside Guanosine
Guanine
GMP-GDP-GTP-cGMP
name the free base and nucleotide of the nucleoside Inosine
Hypoxanthine
IMP
name the free base and nucleotide of the nucleoside Uridine
Uracil
UMP-UDP-UTP
name the free base and nucleotide of the nucleoside Cytidine
Cytosine
CMP-CDP-CTP
name the free base and nucleotide of the nucleoside Thymidine
Thymine
TMP-TDP-TTP
What do nucleosides end in
ine
what is needed to synthesize purine nucleotides
ATP
what is ATP required for each
Kinase
synthetase
ring closure step
is this a ATP utilizing pathway
YES
What is the starting material for synthesis of purine nucleotides
Ribose 5 phosphate
what pathway does Ribose 5 phosphate come from
PPP or pentose phosphate pathway
what does PRPP stand for
Phosphoribosyl 1-phosphate pyrophosphate AKA 5 phosphoribosyl 1 pyrophosphate
PRPP does what
Nucleotide salvage
biosynthesis of tryptophan and histidine
Ribose 5 phophate to
PRPP to
?
IMP
what is the precursor to other purine nuceotides
inosine monophosphate IMP
what must be made first to turn into AMP and GMP
IMP
what does not accumulate significantly within the cell
IMP
what is IMP the starting material to
GMP
AMP
what do reactions need
nitrogen from glutamine
what is the nitrogen donor
glutamine
what is the first committed step
5 phosphoribosyl 1 pyrophosphate to 5 phosphoribosylamine
what will inhibit reaction
AMP and GMP or increased product will inhibit reaction
what is needed
ATP
what is the methyl donor
THF Tetrahydrofolate
the ATP utilizing step is
5 phosphoribosylamine to glycinamide ribonucletide GAR
what is the reaction that is adding a Carbon
GAR to FGAR by adding a methyl group (THF) by enzyme GAR transformylase
what is also part of these reactions
glutamine to glutamate
ATP utilizing pathway is
FGAR to AIR
another ATP utilizing pathway is
AIR to SACAIR
what is released
fumarate
by adding a carbon what is the reaction
SACAIR to FAICAR
what is the precursor
IMP
what is the reaction the precursor is found
FAICAR to IMP
how many reactions does it take to get to AMP and GMP from IMP
2 reactions
what is all used in the pathway
carbon
nitrogen
methyl
CO2 Aspartate N10 formyl THF gluatmine glycine Are all steps to what
IMP
what is brought in
aspartate
what inhibits amidophosphoriboooosyl transferase
hypoxanthine
T/F
purine nucleotides are synthesized PREFERENTIALLY by salvage pathways so long as hypoxanthine is available
true
what are the three bases to the desired product
Adenine +PRPP +ATP >AMP + PPi
Guanine + PRPP + GTP> AMP + PPi
Hypoxanthine + PRPP > IMP + PPi
name the steps
PRPP 5 phosphoribosylamine GAR FGAR AIR SACAIR FAICAR IMP > to either AMP or GMP and all sent back to IMP by either: Salvage pathways> AMP, GMP, Hypoxanthine
what happens to nucleotides during degradation of purines to uric acid
nucleotides are converted to nucleosides
what happens to nucleosides during degradation of purines to uric acid
nucleosides are converted to free bases
what happens to free bases during degradation of purines to uric acid
free bases are converted to a common base (Xanthine)
what is the common base
xanthine
what happens to xanthine during degradation of purines to uric acid
xanthine is converted to uric acid
what happens to uric acid during degradation of purines to uric acid
uric acid is excreted
what is the purine monophosphate IMP broken down to a nucleoside called and then what is the name broken down to a free base called
IMP
Inosine
hypoxathine
what is the purine monophosphate XMP broken down to a nucleoside called and then what is the name broken down to a free base called
XMP
xanthosine
xanthine
what is the purine monophosphate GMP broken down to a nucleoside called and then what is the name broken down to a free base called
GMP
Guanosine
Guanine
what is the purine monophosphate AMP broken down to a nucleoside called and then what is the name broken down to a free base called
AMP
Adenosine
Hypoxanthine
what is xanthine oxidized to form
uric acid
what are the free bases that are converted to a common base xanthine
Guanine
Hypoxanthine
Inosine>Hypoxanthine
Adenosine > Inosine>Hypoxanthine
Xanthine to Uric acid by what enzyme
xanthine oxidase
what is the final metabolic product of purine catabolism in primates
uric acid
what is caused by an accumulation of excess uric acid
gout
uric acid has what kind of solubility
low
what is gout
precipitation of needle shaped crystals in soft tissue (joints)
what is used to treat gout
allopurinol
what causes inhibition of xanthine oxidase
allopurinal
what is a nitrogen base
a purine or a pyrimidine
where is the addition of the sugar ribose from
PRPP
what is the initial ring formation in the ATP utilizing pathway
CAD
in the ATP utilizing pathway what is oxidation with
with a dehydrogenase
where is carbamoyl phosphate from
the urea cycle
in the urea cycle where is carbamoyl phosphate from
mitochodrial matrix
in the pyrimidine synthesis cycle where is carbamoyl phosphate from
cytosol
what is the ring formation enzymes
CAD
Carbomoyl phosphatase synthetase
Aspartate transcarbamoylase
Dihydroorotase
what is the first nitrogen donor
glutamine
what happens during oxidation with a dehydrogenase
hihydroorotate to orotate by dihydroorotase dehydrogenase with unbiquinone
orotate to UMP by ?
adding PRPP and taking away CO2 by UMP synthase
what does not donate nitrogen to pyrimidine
glycine
what donates to UMP
glutamine
HCO3-
Aspartate
what donates nitrogen
glutamine
UTP to CTP by CTP synthetase is
amination of UTP
CTP synthesis to what enzymes by what reactants
UMP > UDP
CMP > CDP
both are to UMP Kinase
UDP > UTP
CDP > CTP
both are to Nucleotide diphosphskinase
what is not salvaged in humans
cytosine
what does have some cytosine deaminase
bacteria and fungi
what is converted to fluorouracil which is toxic and what is it converted by
fluorocytosine is converted to flourouracil by cytosine deaminase
what are the salvage pathways of pyrimidines
uracil + PRPP > UMP + PPi
thymidine + ATP > TMP + PPi
what is the enzyme in the formation of deoxynucleotides
ribonucleotide reductase
ribonucleotide reductase does what to NDP
turns it into dNDP
adenine, guanine, and uracil
direct reduction of the 2’ hydroxyl group
enzyme is ribonucleotide reductase
how is deoxy-TMP or TMP unique to DNA
has its own special pathway
still utilizes ribonucleotide reductase
what is TMP
Thymidine monophosphate
what does the reduction of ribonucleotides to deoxynucleotides only occur as
diphosphates not monophosphates
thymidine synthesis name the pathway
UMP UDP dUDP dUTP (add a methyl donor THF) dUMP TMP TDP TTP
5 important things for thymidine synthesis
1) separate pathway
2) main enzyme is thymidylate synthase
3) folic acid is a coenyzme
4) methyl group difference THP
5) NADPH is utilized
what is the donor that donates:
N for purines
N and C for pyrimidines
aspartate
Name the donor that donates:
N for purines
N for pyrimidines
Glutamine
Name the donor that donates:
N for purines
Glycine
Name the donor that donates:
C for pyrimidines
Bicarbonate
Name the donor that donates:
C for purines
Carbon dioxide
Name the donor that donates:
C for purines
C for pyrimidine (thymidine)
Folic acid (THF)
what are the raw materials for making nucleotides
nitrogen donors= GAG
sugar donor= ribose form from the PPP
Carbon donor= folic acid, AA, CO2, bicarbonate, THF
Energy donor= ATP
what is the precursor purine nucleotide
IMP to AMP and/or GMP
What is the precursor pyrimidine nucleotide
UMP to CMP and/or TMP
purine degradtion
common base= xanthine
metabolic pathway fro excretion= uric acid or urate
to much uric aciod= precipitation of uric acid crystals= gout
PRPP
ribose with a phosphate and a pyrophosphate
used to creat both purine and pyrimidine nucleotides