InteraccionesLípidos - Proteínas
• Serum albumin is the carrier of fatty acids in the blood.
• Serum albumin is the most plentiful protein in blood plasma.
• Each protein molecule can carry seven fatty acid molecules.
• When our body needs energy or needs building materials, fat cells release fatty acids into the blood. There, they are picked up by serum albumin and delivered to distant parts of the body.
Interacciones Lípidos - Proteínas
Serum albumin
http://www.rcsb.org/pdb
InteraccionesLípidos - Proteínas
Proteínas de membrana
MEMBRANE PROTEINS OF KNOWN STRUCTURE
http://www.mpibp-frankfurt.mpg.de/michel/public/memprotstruct.html
Dominios Básicos de Estructura Secundaria en las Proteínas de Membrana
Bacteriorrodopsina(hélices )
Porina(Cadenas )
H+H+H+
NADH NAD++ H+
succinatefumarate + 2H+
FAD
FeS
2e-
2e- UQ
UQH2
a CuBa3
FMN
Fe-S
FeS
bH
bL
CuA
Mitochondria
Complex INADH:quinoneoxidoreductase
Complex IIsuccinate:quinone
oxidoreductase
Complex IIIquinol:cytochrome c
oxidoreductase
Complex IVcytochrome c: oxygen
oxidoreductase
2O2 + H2 2H2O O2
The mitochondrial respiratory chain
H+H+H+
NADH NAD++ H+
succinatefumarate + 2H+
FAD
FeS
2e-
2e- UQ
UQH2
a CuBa3
FMN
Fe-S
FeS
bH
bL
CuA
Mitochondria
Complex INADH:quinoneoxidoreductase
Complex IIsuccinate:quinone
oxidoreductase
Complex IIIquinol:cytochrome c
oxidoreductase
Complex IVcytochrome c: oxygen
oxidoreductase
2O2 + H2 2H2O
Claudio Gomes - ITQB, Oeiras, Portugal
Complex INADH:quinone oxidoreductase
Mitochondria• 42/43 subunits / ~ 900 kDa • Cofactors: 1-2 FMN, 7-8 FeS• Covalently bound lipid• ~ 3 bound quinol molecules• Proton translocation
Prokaryotic• 14 subunits / ~500 MDa• ~ 55 TM helices• Cofactors: 1 FMN, up to 9
FeS
Claudio Gomes - ITQB, Oeiras, Portugal
Complex IIsuccinate:quinone oxidoreductase
Mitochondria• 4 subunits• 1 FAD covalently bound• FeS clusters ([2Fe-2S]; [4Fe-4S], [3Fe-
4S])• 2 TM segments containing heme b
Prokaryotic• Identical to the mitochondrial
complex except at the TM / heme b composition
Claudio Gomes - ITQB, Oeiras, Portugal
Complex IIIquinol:cytochrome c oxidoreductase
Mitochondria• 11 subunits / dimer / ~240 kDa• Three core subunits • Contains up to 8 additional subunits• Cofactors: 2 cyt b, cyt c1, Rieske
[2Fe-2S]• H+ translocation ( Q-cycle
mechanism)
Prokaryotic • 3 core subunits and cofactors
present
Claudio Gomes - ITQB, Oeiras, Portugal
Z. Zhang et al (1998) Nature 392, 677-684
The b-c1 complex – Complex III
http://www.life.uiuc.edu/crofts/bc-complex_site/
Electron-Proton Transfer in Complex III
Complex IVcytochrome c : oxygen
oxidoreductase
Mitochondria• 13 subunits (3 core) • Binuclear CuA site, heme a,
Heme-copper site CuA-a3
1979 1990 1995
Claudio Gomes - ITQB, Oeiras, Portugal
Cytochrome c oxidase – Complex IV
Cytochrome Oxidase Home Page
http://www-bioc.rice.edu/~graham/CcO.html
Subunit III (in blue) with an embedded phospholipid. Subunit IV (green, unique to this enzyme) Subunit I (yellow) - Subunit II (purple) Antibody fragment (cyan) used to drive crystallization.
Complex IVcytochrome c : oxygen
oxidoreductase
Mitochondria• 13 subunits (3 core) • Binuclear CuA site, heme a,
Heme-copper site CuA-a3
Prokaryotic • 3-5 subunits (including core sub I-III)• Multiple heme types (e.g. A, As, B, O) • Proton pumps • Superfamily of heme-copper
oxidases
Claudio Gomes - ITQB, Oeiras, Portugal
Terminal Oxidases Diversity
H+
b CuB
o3
O2
H2O
Quinol oxidases(eg. bo3 Ec)
H+
b CuBb3
O2
H2O
FixN-type oxidases
(eg. cbb3 Pd)
b db
Cytochrome bd(eg. bd Ec)
Fe Fe
Alternative oxidase(eg. plant mitochondria)
Heme-copper oxidases
H+
a CuB
a3
CuA
O2
H2OCytochrome
oxidases(eg. aa3 Pd)
Non heme-copper oxidases
Claudio Gomes - ITQB, Oeiras, Portugal
Aerobic metabolism
is more efficient
AerobicBacteria
The endosymbiotic theory suggests that eukaryotes acquired respiration capability by the symbiosis with an oxygen respiring bacteria
Ancestral anaerobic eukaryote
Aerobic Eukaryote
Some bacterial genes move to the nucleus and the bacterial endosymbionts become mitochondria
Non-photosynthetic Eukaryote
Endosymbionts become mitochondria
Photosynthetic cyanobacterium
New cell can make ATP from sunlight
Claudio Gomes - ITQB, Oeiras, Portugal
Mitochondrial oxidative phosphorylation
http://www.life.uiuc.edu/crofts/bioph354/lect8.htmlBiophysics 354, Lecture 8
Complex IComplex II
Complex III Complex IVATPase
CambridgeUniversity
RobertPoole
F0F0
H+H+
Respiratory chainRespiratory chain
++ --
Inter-Membrane
space
Inter-Membrane
space Inner membraneInner membrane MatrixMatrix
F1F1
H+H+
ADP + PiADP + Pi
ATP + H2OATP + H2O
CambridgeUniversity
RobertPoole
CambridgeUniversity
RobertPoole
CambridgeUniversity
RobertPoole
HOW MUCH ATPDO WE PRODUCE?HOW MUCH ATPDO WE PRODUCE?
AT RESTAdult converts one half body weight equivalent of ATP per day
AT RESTAdult converts one half body weight equivalent of ATP per day
NORMALAdult converts body weight equivalent of ATP per day
NORMALAdult converts body weight equivalent of ATP per day
HARD WORKAdult converts up to 1000 kg ATP per day
HARD WORKAdult converts up to 1000 kg ATP per day
1000 kg
70kg? £1M?70kg? £1M?
ATP S INTASA
Los Elementos y Moléculas de la VidaLosada, Vargas, Florencio y De la Rosa (1998-9)Editorial Rueda, Madrid
Schnitzer (2001) Nature 410, 878 - 881
ATP synthase — energy converter.
W. Junge et al. (1997) TIBS 22, 420-423
Rotational mechanism of ATP synthase
Abrahams et al. (1994) Nature 370, 621-628.
viewed from the cytoplasmatic side
EE
TP
TP
DP
DP
ADP + Pi
ATP
ADP + Pi ADP + Pi
AD
P + P
i
AD
P + P
i
ATPA
TP
O
O OT T T
L L
L
Energy
Structure of F1 from bovine heart mitochondria
Animation of ATP synthesis by F0F1 complexes
Animation of ATP-driven subunit rotation
http://www.life.uiuc.edu/crofts/bioph354/lect10.html
ATP synthaseAnimation of the complete mechanism
Lecture 10, ATP synthase
Yasuda et al (2001) Nature 410, 898-904
Observation of F1 rotation
Bacteriorhodopsin
Subramaniam & Henderson (2000) Nature 406, 653 - 657
The light-induced all-trans to 13-cis isomerization of the retinal results in deprotonation of the Schiff base followed by alterations in protonatable groups withinbacteriorhodopsin.
Displacement of Schiff base on deprotonation
Observed conformations of
retinal derivatives
Sass et al. (2000) Nature 406, 649 - 653
Details of the structural differences between the ground state (purple) and the M2 intermediate (yellow).
Extracellular view Cytoplasmic view
Kühlbrandt (2000) Nature 406, 569 - 570
Molecular mechanism of proton (H+) pumping in bacteriorhodopsin
Spudich JL (2002) Science 288, 1358-9
The four archaeal rhodopsins in H. salinarum
Béjà et al. (2000) Science 289, 1902-1906
Phylogenetic analysis of proteorhodopsin with archaeal and Neurospora crassa (NOP1) rhodopsins
X. Gomis & M. Coll, Diario de Sevilla, 15 Marzo 2001
Conjugación bacteriana: Transferencia de plásmido con resistencia a un determinado antibiótico
Bacterias resistentes a los antibióticos
A. Vila, Diario de Sevilla, 10 Julio 2001
A. Vila, Diario de Sevilla, 10 Julio 2001
Bacteria de la tuberculosis. Uno de los muchos microorganismos que ha desarrollado inmunidad frente a los fármacos
A. Vila, Diario de Sevilla, 10 Julio 2001
El anillo de beta-lactama
A. Vila, Diario de Sevilla, 10 Julio 2001
Beta-lactamasa. Metaloproteína de cinc que destruye a los antibióticos
The bacterial conjugation protein TrwB resembles ring helicases and F1-ATPaseGomis et al. (2001) Nature 409, 637-641
The bacterial conjugation protein TrwB resembles ring helicases and F1-ATPaseGomis et al. (2001) Nature 409, 637-641
Lateral view
View along the 6-fold axis
S Murakami et al. (2002) Nature 419,587
Bacterial multidrug efflux transporter
S Murakami et al. (2002) Nature 419,587
Bacterial multidrug efflux transporter
The emergence of bacterial multidrug resistance is an increasing problem in the treatment of infectious diseases. Multidrug resistance often results from the overexpression of a multidrug efflux system.
AcrB is a major multidrug exporter in Escherichia coli. It cooperates with a membrane fusion protein, AcrA, and an outer membrane channel, TolC.
Substrates translocated from the cell interior through the transmembrane region and from the periplasm through the vestibules are collected in the central cavity and then actively transported through the pore into the TolC tunnel.
The AcrB system extrudes cationic, neutral and anionic substances, and pumps out some beta-lactams with multiple charged group. AcrAB catalyses efflux driven by proton motive force.
N N NN N H N HH N H N
N H
N H N H
N H3
3 3
3+
+ +
+
C O OC O OC O OC O O --
--
( h i s t i d i n a s p a r a l e l a s ) ( h i s t i d i n a s p e r p e n d i c u l a r e s )
CITO CRO M O -559 TRANS M E M B RANA Lb