Atp production

ATP

1. ATP Production
Prepared By:
Simranjeet Kaur
Asssistanat Professor Pharmacology
PCTE Group of Institutions

2. Living cells require energy from outside sources
Energy flows into an ecosystem as sunlight and leaves as heat
Photosynthesis generates O
2
and organic molecules, which are
used in cellular respiration
Cells use chemical energy stored in organic molecules to
regenerate ATP, which powers work

3. Adenosine Tri-Phosphate (ATP)
ATP is the energy unit of the cell.
ATP is composed of an Adeno. Group, a sugar group and three
phosphates.
ATP is easily recycled.
The cell converts Adenosine Di-Phosphate (ADP) into ATP by
the addition of a phosphate.

4. Fig. 9-2
Light
energy
ECOSYSTEM
Photosynthesis
in chloroplasts
CO
2 + H
2O
Cellular respiration
in mitochondria
Organic
molecules
+ O
2
ATP powers most cellular work
Heat
energy
ATP

5. The Principle of Redox
Chemical reactions that transfer electrons between reactants are
called oxidation-reduction reactions, or redox reactions
•In oxidation, a substance loses electrons, or is oxidized
In reduction, a substance gains electrons, or is reduced (the amount
of positive charge is reduced)

6. Redox Reactions: Oxidation and
Reduction
The transfer of electrons during chemical reactions releases
energy stored in organic molecules
This released energy is ultimately used to synthesize ATP

7. ATP powers cellular work by coupling
exergonic reactions to endergonic reactions
A cell does three main kinds of work:
Chemical
Transport
Mechanical
To do work, cells manage energy resources by energy coupling,
the use of an exergonic process to drive an endergonic one
Most energy coupling in cells is mediated by ATP

9. ATP
•ATP (adenosine triphosphate) is the cell’s energy shuttle
•ATP is composed of:
– ribose (a sugar)
–adenine (a nitrogenous base)
–Three phosphate groups

10. Fig. 8-8
Phosphate groups
Ribose
Adenine

11. •The bonds between the phosphate groups of ATP’s tail can be
broken by hydrolysis
•Energy is released from ATP when the terminal phosphate bond
is broken
•This Third Phosphate bond contains LOTS of Energy
•This release of energy comes from the chemical change to a state
of lower free energy, not from the phosphate bonds themselves

12. Fig. 8-9
Inorganic phosphate
Energy
Adenosine triphosphate (ATP)
Adenosine diphosphate (ADP)
PP
PPP
P ++
H
2
O
i

13. The three types of cellular work are:
mechanical
transport
chemical
Each is powered by the hydrolysis of ATP
In the cell, the energy from the exergonic reaction of ATP
hydrolysis can be used to drive an endergonic reaction

14. Fig. 8-11
(b) Mechanical work: ATP binds noncovalently
to motor proteins, then is hydrolyzed
Membrane protein
P
i
ADP
+
P
SoluteSolute transported
P
i
Vesicle Cytoskeletal track
Motor protein Protein moved
(a) Transport work: ATP phosphorylates
transport proteins
ATP
ATP

15. Phosphorylation
ATP drives endergonic reactions by phosphorylation,
transferring a phosphate group to some other molecule, such
as a reactant
The recipient molecule is now phosphorylated

16. Phosphorylation
The process of Phosphorylation converts a relatively low
energy compound (ADP) into a higher energy compound
(ATP)
ADP (Adenosine Di-Phosphate)- Contains an Adenosine, a
ribose group, and two Phosphate groups.

17. Fig. 8-12
P
i
ADP+
Energy from
catabolism (exergonic,
energy-releasing
processes)
Energy for cellular
work (endergonic,
energy-consuming
processes)
ATP+H
2
O

18. The ATP Cycle
ATP can be produced from existing ADP molecules
A phosphate is added to ADP at the mitochondria.
Requires ATP synthase - A protein complex in the
mitochondria that acts a molecular mill and converts ADP into
ATP.

19. Fig. 9-UN7
INTER-
MEMBRANE
SPACE
H
+
ATP
synthase
ATPADP +P
i
H
+
MITO-
CHONDRIAL
MATRIX

20. The Regeneration of ATP
ATP is a renewable resource that is regenerated by addition of a
phosphate group to adenosine diphosphate (ADP).
Requires ATP synthase and H ions (from water.)
•The energy to phosphorylate ADP comes from catabolic
reactions in the cell.
•The chemical potential energy temporarily stored in ATP can
then be used to drive most cellular work.