1. Interacciones Proteína - Proteína Fuertes (t = s, min) Complejos proteicos (estables) Débiles (t =  s, ms) Complejo intermediario (transitorio) en una reacción enzimática

2. Schwikowski et al.(2000) Nature Biotech. 18, 1257 - 1261 Interactions between functional groups

3. Interactions between proteins of different compartments Schwikowski et al.(2000) Nature Biotech. 18, 1257 - 1261

4. Tong et al. (2002) Science 295, 321-324 Yeast SH3 domains — which recognize proline- rich peptides — generated a network containing 394 interactions among 206 proteins

5. An interaction map of the yeast proteome assembled from published interactions Schwikowski et al.(2000) Nature Biotech. 18, 1257 - 1261

6. ..\..\LINKS\Ho Nature(2002).pdf Ho et al. (2002) Nature 415, 180 Protein network in Saccharomyces cerevisiae

7. Kumar & Snyder (2002) Nature 415, 123-124 Ho, Y et al. (2002) Nature 415, 180 - 183 Analysing protein interactions: Systematic identification of protein complexes in Saccharomyces cerevisiae by mass spectrometry

8. T. Iiri et al. (1998) Nature 394, 35-38 How does a trimeric G protein on the inside of a cell membrane respond to activation by a transmembrane receptor? Trimeric (  ) G proteins relay signals from transmembrane receptors to intracellular enzymes and ion channels, thereby mediating vision, smell, taste and the actions of many hormones and neurotransmitters

9. T. Iiri et al. (1998) Nature 394, 35-38 The GTPase cycle of trimeric G proteins The 'turn-on' step begins when the activated receptor (R*) associates with the trimer of (  GDP  ), causing dissociation of GDP. Then GTP binds to the complex of R* with the trimer in its 'empty' state (  e  ), and the resulting GTP-induced conformational change causes  GTP to dissociate from R* and from . After the 'turn-off' step (hydrolysis of bound GTP to GDP and inorganic phosphate, P i ),  GDP reassociates with .

10. T. Iiri et al. (1998) Nature 394, 35-38 Contacts between G  (left) and G  -GDP (right) Red dashed lines indicate contacts that appear to be required for receptor activation but not for G  –G  association; green dashed lines indicate contacts that are important for both functions

11. T. Iiri et al. (1998) Nature 394, 35-38 How does a trimeric G protein on the inside of a cell membrane respond to activation by a transmembrane receptor? Biomedical relevance: G-protein mutations in patients with hypertension and inherited endocrine disorders enhance or block signals from stimulated receptors.

12. A. Chiarugi & M.A. Moskowitz (2002) Science 297, 200 PARP-1: A Perpetrator of Apoptotic Cell Death Apoptotic cell death is triggered by activation of the nuclear enzyme poly(ADP-ribose) polymerase-1 (PARP-1). Through unknown mechanisms, PAR formation and NAD + depletion may trigger a cascade of events.

13. Navarro et al. (1997) J. Biol. Inorg. Chem. 2, 11-22

14. Cyt c 6 Pc PS I b6fb6f PSI-driven Electron Transfer Fd light

15. Navarro et al. (1997) J. Biol. Inorg. Chem. 2, 11-22

16. PROKARYOTES Time (10 9 years ago) 4 3 2 1 0 Atmospheric Level (fractions of 21% v/v) 0.001 0.01 0.1 1 (Adapted from Peschek, 1996) Oxygen content of the earth's atmosphere EUKARYOTES Photosynthetic O 2 production Pasteur Point (O 2 respiration) Berkner-Marshall Point (Terrestrial life)

17. Cu Fe S 2- SO 4 2- Time (10 9 years ago) 4 3 2 1 0 Availability (Adapted from Williams & Silva, 1997)

18. Plastocyanin Cu ligands: His-35 Cys-84 His-87 Met-92

19. Heme ligands: His-19 Met-61 Cytochrome c 6

20. ___________________________________________________ Organism Protein pI ___________________________________________________ Spinach Plastocyanin 4.2 Monoraphidium Plastocyanin 3.7 Cytochrome c 6 3.6 Anabaena Plastocyanin 9.0 Cytochrome c 6 9.0 Synechocystis Plastocyanin 5.5 Cytochrome c 6 5.6 ____________________________________________________ Isoelectric point of cytochrome c 6 and plastocyanin isolated from different organisms

21. Cytochrome c 6 Plastocyanin De la Rosa et al. (2002) Bioelectrochemistry 55, 41-45

22. Photosynthetic organisms growing under controlled conditions

24.  A = 2 x 10 -3

25. Routes c: 1 2 3 3' 4 h b: 1 2 2' 3' 4 h a: 1 1' 2' 3' 4 h Prot red + PSI red 1 [Prot red... PSI red ]* K R 3 Prot ox + PSI red k et 4 [Prot red... PSI ox ]* h 3' Prot red + PSI ox [Prot red... PSI ox ] h h K' R K' A 1'2' [Prot red... PSI red ] K A 2 De la Rosa et al. (2002) Bioelectrochemistry 55, 41-45

27. KINETIC TYPES FOR THE REACTION MECHANISM Type I Prot red + PSI ox  Prot ox + PSI red Type II Prot red + PSI ox  [Prot red... PSI ox ]  Prot ox + PSI red Type III Prot red + PSI ox  [Prot red... PSI ox ]  [Prot red... PSI ox ]*  Prot ox + PSI red KINETIC TYPES FOR THE REACTION MECHANISM Type I Prot red + PSI ox  Prot ox + PSI red Type II Prot red + PSI ox  [Prot red... PSI ox ]  Prot ox + PSI red Type III Prot red + PSI ox  [Prot red... PSI ox ]  [Prot red... PSI ox ]*  Prot ox + PSI red KINETIC TYPES FOR THE REACTION MECHANISM Type I Prot red + PSI ox  Prot ox + PSI red Type II Prot red + PSI ox  [Prot red... PSI ox ]  Prot ox + PSI red Type III Prot red + PSI ox  [Prot red... PSI ox ]  [Prot red... PSI ox ]*  Prot ox + PSI red KINETIC TYPES FOR THE REACTION MECHANISM Type I Prot red + PSI ox  Prot ox + PSI red Type II Prot red + PSI ox  [Prot red... PSI ox ]  Prot ox + PSI red Type III Prot red + PSI ox  [Prot red... PSI ox ]  [Prot red... PSI ox ]*  Prot ox + PSI red Navarro et al. (1997) J. Biol. Inorg. Chem. 2, 11-22

28. Flexibilidad estructural de la plastocianina