slide1 l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Análisis del transporte de electrones en bioquímica PowerPoint Presentation
Download Presentation
Análisis del transporte de electrones en bioquímica

Loading in 2 Seconds...

play fullscreen
1 / 71

Análisis del transporte de electrones en bioquímica - PowerPoint PPT Presentation


  • 194 Views
  • Uploaded on

Análisis del transporte de electrones en bioquímica. 1) Los componentes A y D son el dador y el aceptor de electrones exógenos, respectivamente. 2) Los componentes B y C de la cadena de transporte de electrones se encuentran en baja concentración en la membrana.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Análisis del transporte de electrones en bioquímica' - brittany


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide2

Análisis del transporte de electrones en bioquímica

1) Los componentes A y D son el dador y el aceptor de electrones exógenos, respectivamente.

2) Los componentes B y C de la cadena de transporte de electrones se encuentran en baja concentración en la membrana.

3) ,  y  catalizan la transferencia de electrones

4) I1, I2 son inhibidores irreversibles de  y , respectivamente.

5) X1 y X2 son dadores de electrones exógenos.

slide3

Diferencia de potencial electroquímico de un ion

Para transferir un mol de ion Xn+ a través de una membrana cuando :

- [Xn+]B [Xn+]A , en ausencia de un campo eléctrico.

G = 2.3 * R * T * log([Xn+]B/[Xn+]A)

- [Xn+]B =[Xn+]A , en presencia de un campo eléctrico.

G =- n * F * 

donde F: constante de Faraday; n: carga del ion;  : potencial eléctrico

- [Xn+]B [Xn+]A , en presencia de un campo eléctrico.

G =- n * F *  +2.3 * R * T * log([Xn+]B/[Xn+]A)

slide4

Potencial electroquímico del protón

n = 1 ; log ([H+]B/ [H+]A) =-pH

H+=- F *  - 2.3 * R* T * pH

Multiplicando por [1/(-F)]

H+/(-F) =  - [2.3 * R* T * (-F)] * pH

A 25 oC, [2.3 * R* T * F] = 0.6

H+/(-F) = p (potencial protón motriz)

p =  + 0.6 * pH

slide7

CHEMIOSMOTIC THEORY

ADP + Pi

ATP

Electron transport

H+-ATPase

how is atp made

Photophosphorylation

How is ATP made?

A H+ gradient in chloroplasts makes ATP via ATP-synthase.

pp. 540

slide12

H+-ATPase

membrana

organisms within the biosphere exchange molecules and energy

Energy of sunlight

Useful chemical bond energy

Light (via plants)

complex carbon,

glucose, amino acids

Autotrophs:

Phototrophs

& chemotrophs

Heterotrophs

CO2, H2O

(e.g. some bacteria, animals, humans)

Chemical oxidations

(via iron &sulfur bacteria)

Need 9 amino acids & 15 vitamins from outside sources

Organisms within the biosphere exchange molecules and energy

1st Law of Thermodynamics:

In any process, the total energy of the universe remains constant.

slide17

H2O O2

NADP NADPH

OBJETIVOS DE LA CLASE

what is photosynthesis

The process by which plants, algae, and some bacteria use solar energy to drive the synthesis of organic molecules (e.g. sugars, starch, etc.) from carbon dioxide (CO2) and water (H2O).

What is photosynthesis?

Fig. 2.40 Molecular Biology of the Cell, 4th. Ed.

slide21

How are plants able to convert light energy into energy that can be utilized by both themselves and heterotrophs? What other organisms can do this?

photosynthesis reactions overview

6 O2

C6H12O6

6 CO2

6 H2O

glucose

oxygen

carbon dioxide

water

ATP, NADPH

Glucose synthesis 

+

+

ATP, NADPH

General reaction 

O2

+

CO2

H2O

+

(CH2O)

Carbondioxide

water

Carbohydrate (e.g. sucrose or starch)

oxygen

Go’ = +686 kcal/mol

Photosynthesis reactions overview
  • Photosynthesis involves two parts:
  • 1. Light reactions(mediated by chlorophylls)
        • use light to generate ATP, NADPH
  • 2. Carbon reactions (also called, “Benson-Calvin cycle”)
        • use ATP, NADPH, CO2 to synthesize sugar & starch
  • Occurs in: prokaryotes: bacteria, blue green algae, in cytoplasmic membrane
  • eukaryotes: chloroplasts
slide23

Anatomy of a plant cell

Fig. 14.34. Molecular Biology of the Cell, 4th. Ed.

an overview of the chloroplast

3 distinct membranes: outer, inner, thylakoid

3 separate internal compartments: intermembrane, stroma, thylakoid lumen

An overview of the chloroplast

grana

Size = 5 m

pp. 529

slide30

Absorption process

Transition of an electron from the ground state to an excited state provided:

A) The energy gap [ground state  excited state] matches the wavelength of light [E = h . c . -1]

2) the translation charge across a chromophore generates a transition electric dipole moment ()

3)  dictates the potential extent of absorption quantified as the extintion coefficient 

slide31

F=photons emitted/photons absorbed

Deactivation processes of the excited states

JCE 76: 1555 (1999)

other pigments antenna pigments accessory pigments
Other pigments, antenna pigments, accessory pigments

Reflects green light; absorbs rest

Reflects yellowlight; absorbs rest

Reflects blue light; absorbs rest

absorbance spectra of other pigments
Absorbance spectra of other pigments
  • The combined absorption of all the chlorophylls cover the entire spectrum of visible light.
slide36

(Chl)

(Chl)*

D+

D

Interconversión de la clorofila

slide38

LUZ

A

D

P  P*

P+

A-

D+

photosystem ii
Photosystem II

Thylakoid membrane

  • Transfers electrons from water to plastiquinone (thus oxidizing it to O2)
  • Generates proton (H+) gradient between thylakoid lumen and stroma

pp. 534

photosystem i
Photosystem I

Thylakoid membrane

Generates reduced ferredoxin (Fd)

PSI reduces NADP+ to NADPH (Fd-NADP-reductase).

pp. 537

overview of electron flow through thylakoid membrane proteins
Overview of electron flow through thylakoid membrane proteins

The Cell: a molecular approach, fig. 10-22

slide50

H2O O2

NADP NADPH

OBJETIVOS DE LA CLASE

slide54

.

.

.

.

.

slide59

Residencia del DNA que codifica para Rubisco

OrganismoLSUSSU

Algas verdes,

plantas, Euglena cloropl.Núcleo

Algas rojas cloropl. cloropl.

Algas marrones cloropl. cloropl.

Dinoflagelados Núcleo X

L8S8

L2

slide62

En la presentacion dice que es una planta C4. Documentos lindos \facultad \para usar \photos\photosynth \general1 (carpeta) \ C4leaf

slide64

Plant performance

PlantC3C4CAM

gH2O/g DM 450-950250-35050-55

Topt(oC) 15-2530-40ca. 35

Ton.DM/(Ha.yr) 20-2535-40low & variable

slide66

(bundle sheath)

C4 photosynthesis. CO2 assimilation

mesophyll

slide67

Cost of concentrating CO2 within the bundle sheath cell

mesophyll

CO2+ 2 ATP + 2 H2O

CO2+ 2 ADP + 2 Pi

bundle sheath

slide71

BIBLIOGRAFIA

PLANT PHYSIOLOGY, 3rd. Ed., L.Taiz & E.Zieger Eds., Ch.7. Photosynthesis: the light reactions Ch.8. Photosynthesis: carbon reactions Sinauer Associates, Sunderland, MA. (2002)

BIOLOGIA CELULAR Y MOLECULAR, 4th. Ed., H.Lodish et al. Eds., Ch.16. Energética celular: glicólisis, oxidación aeróbica, y fotosíntesis. Editorial Panamericana, Buenos Aires. (2000)

BIOENERGETICS 2, D.G.Nicholls & S.J.Ferguson. Academic Press, London. (1992)