文档介绍：Biochemistry II --Metabolism: The degradation and synthesis of biomolecules. by Professor Zengyi Chang (昌增益教授) Tel: 6277-2251 E-mail: ******@.
1. An Overview of Metabolism
The Definition of Metabolism
The highly work of chemical transformations.
Degradation (decreasing order, thus energy releasing) to provide energy, catabolism;
Synthesis (increasing order, thus energy consuming) to provide building materials, anabolism.
The energy supply
and demand in
Heterotrophs:
the ATP-ADP cycle
The Roles of metabolism
Extract energy and reducing power from the environment (photosynthesis and oxidative degradation of nutrients);
Generation (interconversion) of all the biomolecules (small and large) for a anism (biosynthesis).
The General Features of metabolism
Occurs in linear, branched or circular pathways;
Highly interconnected (“Every road leads to Rome”).
Highly regulated to achieve the best economy (“Balanced supply and demand”).
The number of reactions is large (over 1000) and the number of types of reactions is relatively small.
Well conserved during evolution: reflecting the unity of the life phenomena (“what happens in bacteria happens in human being”).
Degradation is convergent
and energy releasing
Synthesis is divergent
and energy consuming
The citric
acid cycle
乙酰辅酶A
草酰乙酸
柠檬酸
异戊烯焦磷酸
Acetyl-CoA: mon degradative
product of sugar, fatty acids and
many amino acids
Coenzyme A: the carrier of activated acyl groups
泛酸
巯基乙胺
Metabolism:
The economy
The unity
The regulation