Metabolisme Asam Nukleat
Metabolisme Asam Nukleat
Metabolisme Asam Nukleat
Degradasi Nucleoprotein
Nucleoprotein
Nucleotidase
Phosphate Nucleoside
Nucleosidase
Base Ribose
PRODUK AKHIR PENCERNAAN ASAM NUKLEAT
Basa Nitrogen :
Purin and Pirimidin
Gula:
Ribosa and Deoksiribosa
Asam fosfor
ABSORPSI
Purin dan Pirimidin yang diperoleh dari
pencernaan asam nukleat diabsorpsi melalui usus
halus
Purin yg tidak terabsorpsi diekresikan melalui usus
besar dan feses
Basa nitrogen yang terabsorbsi dibawa ke hati dan
didegradasi
Ribosa diabsorpsi dan dikatabolisme menjadi
energi
METABOLISME ASAM NUKLEAT
dGDP dGTP
ANTIMETABOLIT /INHIBITOR
PURIN NUKLEOTIDA
OH SH
N N
N N
N N N N
H H
hypoxanthine 6-MP
6 MERCAPTA PURINE
6 Mercapta Purine adalah inhibitor
Enzim:
Adenyl Succinase
IMP Dehydrgenase
Menurunkan kadar AMP dan GMP
Folat analogs
NH2 R O COOH
N
N CH2 N C NH C CH2 CH2 COOH
H
H2N N N
R=H:AP R=CH3:TXT
MTX
OH H O COOH
N
N CH2 N C NH C CH2 CH2 COOH
H
H2N N N
folic acid
ANTI CANCER DRUGS: METHOTREXATE
Methotrexate, one of the earliest anti-cancer drugs,
inhibits folate metabolism
Folate provides methyl groups for biosynthetic
reactions
It is essential for the conversion of dUMP to TMP
It provides carbon for the purine ring.
Sulfonamides are effective anti-
bacterial agents
Methotrexate and Aminopterin are
folic acid analogs that have been
used in cancer chemotherapy
SUMMARY OF PYRIMIDINE
BIOSYNTHESIS
dTMP dTDP dTTP
dUMP dUDP
CDP CTP
O O
F CH3
HN HN
O N O N
H H
5-FU thymine
5-fluorouracil
(5-FU) is used as a
chemotherapeutic
agent in the
treatment of
cancers
5-fluorocytosine is
used as an
antifungal drug
5-fluoroorotate is an
effective
antimalarial drug
The 5-Fluoro substitution
inhibits on the mechanism
of action of Thymidylate
Synthase.
Which in turn affects DNA
synthesis.
DEGRADASI PURINE
O O
C C H
N C
HN C HN C
CH N
HC C HC C
N N N
N H H
Hypoxanthine Allopurinol
Xanthine oxidase
Xanthine oxidase
DEGRADASI PIRIMIDIN