energy and metabolism lehninger (ch 13) biochem5 (ch14) kegg s. 14.2

Energy andmetabolism

http://bcs.whfreeman.com/lehninger (Ch 13)

http://bcs.whfreeman.com/biochem5 (Ch14)

http://www.genome.ad.jp/kegg

S. 14.2.

Reminder in Thermodynamics

• First Law (conservation of energy)• Second Law (entropy of the Universe increases in spontaneous processes)

• concepts of open, closed and isolated systems• sign conventions for energy changes

• Free energy (G) (exergonic - endergonic)• Enthalpy (H) (exothermal - endothermal)• Entropy (S)

G = H - TS = - RT lnQ

See Living Graph 13-3

Entropy

1. Teakettle

2. Glucose oxidation

3. Entropy (randomness) and information

There is a tide in the affairs of men,Which, taken at the flood, leads on to fortune;Omitted, all the voyage of their lifeIs bound in shallows and in miseries. (Brutus) - Shakespeare: Julius Caesar, Act 4, Scene 3

ENERGY CONTENT(fuels, sunlight)

WORK

chemical synthesis

mechanical work

osmotic and electricgradients

transmission of genetic information

light

HEAT ENTROPY CHANGE

increases in the surroundings:catabolic end products are small

decreases in the cell :anabolic end products are large

sophisticated molecules

L. II-3. S. 14-12.

L. 1-26. See also “Energetic Coupling” among “Conceptual Insights” on Stryer website

Free energy in coupled reactions

L. 13-8,12

L. 13.1.

L. 13.2.

ATP hydrolysis and phosphorylation potential

See also Living Figure “Box 13-1”

L. 13-10,11

L. T-13-6

L. 13-9

L. 13-3,4

L. 13-5

Reperfusion in the presenceof cardioprotective agents

Ischaemia

Normoxia

CrP-ATP -ATP -ATP

In situ study of energy metabolism:Monitoring of high-energy phosphorus metabolite levels

in perfused rat hearts using 31P NMR spectroscopy

Reperfusion

PCr

Pi

ATP ATP ATP

Effect of PARP inhibitors on the recovery of creatine phosphate during ischemia-reperfusion

0

20

40

60

80

100

120

3 6 9 3 14 25 3 6 9 12 15

perfusion time (min)

CrP

( %

of n

orm

oxi

c va

lue)

Control

4-OHQ

HO-3089

normoxia ischemia reperfusion

*

*p<0.05

Effect of PARP inhibitors on the recovery of ATP during ischemia-reperfusion

0

20

40

60

80

100

120

3 6 9 3 14 25 3 6 9 12 15

perfusion time (min)

AT

P (

% o

f n

orm

oxi

c v

alu

e)

Control

4-OHQ

HO-3089

normoxia ischemia reperfusion

*

* p<0.05

Effect of PARP inhibitors on the utilization of inorganic phosphate

during ischemia-reperfusion

0

20

40

60

80

100

120

3 6 9 3 14 25 3 6 9 12 15

perfusion time (min)

Pi (

% o

f e

nd

-isc

he

mic

val

ue

)

Control

4-OHQ

HO-3089

normoxia ischemia reperfusion

*

* p<0.05

L. 13-6,7

Electron transfer as a form of energy transfer

Electron affinity, oxidative/reductíve capacity electromotive force

E = E° +0.026V/n ln[ox]/[red]

G = -nF E

Deficiency: pellagra (dermatitis, diarrhea, dementia, death)

Regulation of metabolic pathways• controlling the amounts of enzymes• controlling the catalytic activities of enzymes• controlling the accessibility of substrates

Role of energy content in regulation

Online resources:

http://bcs.whfreeman.com/lehninger (Ch13)

http://bcs.whfreeman.com/biochem5 (Ch14)

For online quizzing give:zoltan.berente@aok.pte.huas instructor’s e-mail address