general metabolism

8/3/2019 General Metabolism

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How the nut rients that we are ingest ing

daily become part o f our body and allowgrowth to occur (what is the f at e of thesugar, f at , prot ein and nucleic acids that

ent er our body along with the food ?)

Why do we become f at by only eat ingsugar?

What is the molecular nat ure of the large

number of genet ic diseases? How can we f ind ways to prevent and t reat them?

What does O2 do for us?

How do the various living organisms

´produceµ and ´consumeµ energy? «

Did you ever ask these questions?Did you ever ask these questions?



Met abolismThe tot alit y of the

t ransformat ion of biomolecules (matt er) and energy



Definition of Metabolism

The ent ire highly int egrat ed andregulat ed network of chemicalt ransformat ions (as st epwise met abolicpathways cat alyzed by many enzymes)

occurring in a living organism (through

which cells ext ract energy and reducingpower f rom its environment , as well as

synthesize the building blocks of its

macromolecules and then themacromolecules themselves).



Metabolism is categorized into two types

Cat abolism (degradat ion): larger

molecules (nut rients and cell

const it uents) are broken down (oft en via

exergonic react ions) to salvage (reuse)their components or/and to generat e

energy.

Anab

oli

sm(bi

osyn

the

sis

):Th

e generat io

nof biomolecules f rom simpler

components (oft en via endergonic

react ions).



Major Roles of Metabolism

Ext ract energy and reducing power(oxidat ive degradat ion of nut rients).

Generat ion (int erconversion) of all

the biomolecules for a livingorganism.

Thus comes the t erm

´Dynamic Biochemist ryµ



(Fuels)

Extract energy and reducing power

ATP: Energy currency

Generate all biomolecules

The role of Metabolism

Also for mobility,transport of nutrients

and so on.



General Features of Metabolism

Occurs in speci f ic cellular (t issue and organ)locat ions as a series of enzyme-cat alyzed linear,branched or circular react ions, or pathways.

Highly coupled and int erconnect ed.

Highly regulat ed (oft en reciprocally) to achievethe best economy (´Balanced supply anddemandµ).

The number of react ions is large (over 1000),

however, the number of t ypes of react ions is relat ively small.

Well conserved during evolut ion: re f lect ing theunit y of the li f e phenomena (´what happens in

bact eria

happen

sin

hu

man beingµ).



Enjoy BiochemistryA course that will allow

you to learn what life isreally all about.

general metabolism

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