4.2.Dark Reaction(Photosynthesis)

DARK REACTIONS
USMAN SUMO FRIEND TAMBUNAN
ARLI ADITYA PARIKESIT
MELINA PISESA
Bioinformatics Group
Department of Chemistry
Faculty of Mathematics and Science
University of Indonesia

DARK REACTIONS
The Light-Independent
Reaction
2 outer
membranes

grana disks
(thylakoids)

stroma
compartment

Chloroplast

ATP
ADP

NADPH
NADP+

18 molecules of ATP
12 molecules of NADPH
One molecule of NADPH ~ 3
molecules of ATP

3 x 12 NADPH = 36 ATP
36 ATP + 18 ATP = 54 ATP

OVERALL REACTION
6 CO2 + 12 NADPH + 12 H2O + 18 ATP

C6H12C6 + 12 NADP+ + 18 ADP + 18 Pi +

6 H2O + 6 O2

C3 Carbon Fixation
(C3 Plants)
Carbon fixation is a process by
which the atoms of atmospheric
carbon dioxide are made available
to organisms in the form of
energy-rich molecules such as
glucose

CALVIN CYCLE( C3 FIXATION )

H 2C

1

OPO32

H 2C



C2

O
H

C

OH

H

C

OH

3
4

H 2C

5

H+ H

OPO32

ribulose-1,5bisphosphate

O

O
C
H2 C

C
C

OH

C

OH

H 2C

3-phosphoglycerate

C

HO

ATP ADP

H

OPO32

2

CO2

C

O

C

OH H2O

H 2C

H

OPO32

C
C

H 2C

O
OH
OPO32

-keto
3-phosphoglycerate
intermediate
(2)

Glyceraldehyde-3-phosphate
Dehydrogenase

O
C
H

OPO32
O

enediolate
intermediate

OH
OPO 3

H 2C

CO2

Phosphoglycerate
Kinase

C
H

O

OPO32

C
H2 C

OPO 3

2

NADPH NADP+
H

OH
OPO 3

CHO

2

1,3-bisphosphoglycerate

Pi

C
H2 C

OH
OPO 3

2

glyceraldehyde3-phosphate

REFFERENCES
http://www.iscid.org/encyclopedia/Rubisco
http://en.wikipedia.org/wiki/C3_carbon_fixation
http://en.wikipedia.org/wiki/Calvin_cycle

http://www.rpi.edu/dept/bcbp/molbiochem/MBWeb/mb2/part1/16calvin.ppt#295,27,Slide 27