Anabolisme Katabolisme Ampibolic

Metabolisme
Susila Sastri
Metabolisme
• Definisi: rangkaian reaksi-reaksi kimia
dalam sel yang terjadi secara
continue dan saling berhubungan
satu dengan yang lain
– Anabolisme
– Katabolisme
– Ampibolic
Overview Metabolisme
Metabolisme
• Bahan bakar tubuh : carbohydrates, fats, dan proteins
( makromolekul)
• Energi : oxidasi :CO2 and H2O.
• Cadangan dalam tubuh : triacylglycerol (fat), glycogen
(carbohydrate)
• Penurunan atau penambahan BB normal: Energi
dipakai – Energi tersedia
• insulin dan glucagon; regulator pemakaian dan
penyimpanan bahan cadangan
• Karbohidrat utama dalam darah : glukosa : regulator
insulin dan glukagon dalam darah
Puasa
• Puasa : hypoglisemia , memicu pamkreas agar
glukagon disekresi
• Glucagon: cadangan carbohydrat
membebaskan glucose ke sirkulasi ( brain)
• Puasa lebih 3 : ketone bodies (derived from fat)
as an alternative fuel supply for the brain.
Anabolisme
•
Biosintesis senyawa biomolekul (glikogen,
protein, trigliserida)
• Butuh Energi (endergonic).
• ATP: ADP + Pi (ATP-ADP cycle)
• Misal
– Glikogenesis
– Glukoneogenesis
– Biosintesa asam lemak
– Biosintesa protein
Katabolisme
•
Pemecahan molekul besar : molekul
kecil (glukosa, asetil KoA, Asam amino)
CO2 dan Energi (ATP)
–
–
CO2 : sirkulasi
ATP : dibebaskan setelah elektron
ditransfer ke O2
• Mis:
–
–
–
Glikolisis
Glikogenolisis
Oksidasi asam lemak
Amphibolic
• Anabolisme dan Katabolisme: terjadi dalam
satu proses metabolism
• Siklus Kreb
– Biosintesis heme, glukosa, asam lemak
– Katabolisme: sitrat, ketoglutarat
Energi
• Oxidation of fuels to generate ATP is called respiration
• Electrons lost from the fuels during oxidative reactions :
transferred to O2 by a series of proteins in the electron
transport chain
• Energy of electron transfer : used to convert ADP and Pi to
ATP by a process known as oxidative phosphorylation
• Satuan Energi :
– Calori
– kilocalorie
– kilojoules (kJ)
The ATP-ADP cycle
Generation of ATP
approximate order in which the processes occur. TG = triacylglycerols; FA
= fatty acid; AA = amino acid; RBC = red blood cell; VLDL = very low
density lipoprotein; I= insulin; % = stimulated by.
Metabolisme KH, Fat AA
TAG = triacylglycerol
Overview Metabolisme KH
Overview of fatty acid metabolism
Overview of amino acid metabolism
Transport and fate of major carbohydrate and
amino acid substrates and metabolites
Transport and fate of major lipid substrates and metabolites
FFA, free fatty acids; LPL, lipoprotein lipase; MG, monoacylglycerol;
TG, triacylglycerol; VLDL, very low density lipoprotein.
Intracellular location and overview of major metabolic pathways