Download Anabolism

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Microbial Metabolism
Anabolism
Ching-Tsan Huang (黃慶璨)
Office: Agronomy Hall, Room 111
Tel: (02) 33664454
E-mail: [email protected]
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Overview of Anabolism
http://lecturer.ukdw.ac.id/dhira/Metabolism/Anabolism.html
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Photosynthesis
Phototrophs
• Photoautotrophs: CO2 as carbon source
• Photoheterotrophs: Organic carbon as carbon
source
Light reaction
• light energy is trapped and converted to chemical
energy
Dark reaction
• reduce or fix CO2 and synthesize cell constituents
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Energy Trapping
Anoxygenic
Oxygenic
Oxygenic
Anoxygenic
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Light Reaction
Chlorophyll and bacteriochlorophyll
Required in photosynthesis
Photosynthetic membranes
Found inside the cell membrane and
include chlorophyll pigments and
other light-gathering apparatus
Eucaryotes &
Cyanobacteria
Green & Purple
Bacteria
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Light Reaction
Reaction center
Participate directly in the conversion of light energy to ATP
Antenna pigments
Harvest light energy and funnel to the reaction center (RC)
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Electron flow in photosynthesis
Oxygenic
Anoxygenic
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Overview of Photosynthesis
Source: U.S. Department of Energy Genome Programs http://genomics.energy.gov.
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Autotrophic fixation of CO2
Autotrophs
obtain energy by trapping
light during photosynthesis or
by oxidizing or reduced
inorganic electron donors
Calvin cycle
• Purple bacteria,
cyanobacteria, algae and
green plants
6 RuBP + 6 CO2
12 PGA
6 RuBP + Fructose 6-P
Prescott et al. Microbiology 5th, 2002
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Autotrophic fixation of CO2
Reverse citric acid cycle
Green sulfur bacteria
Hydroxypropionate
pathway
• Green nonsulfur
bacteria
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Methyltrophy
C1 Assimilation
The serine pathway
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Methyltrophy
C1 Assimilation
The ribulose
monophosphate
pathway
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Synthesis of pyruvate to glucose
Gluconeogenesis: Heterotrophs synthesize sugars
by reducing organic molecules
Glucoeogenesis
Glycolysis
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Synthesis of Sugars
Gluconeogenesis
 synthesize glucose and fructose from
noncarbohydrate precursors
Sugar nucleoside diphosphates
 synthesis of other sugars ,
polysaccharides, and bacterial cell
walls
ATP + glucose 1-P 
ADP-glucose + PPi
(glucose)n + ADP-glucose 
(glucose)n+1 + ADP
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Synthesis of Polysaccharides
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Synthesis of amino acids
Phosphoenolpyruvate
Oxaloacetate
-ketoglutarate
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Lipid synthesis
Fatty acid synthesis
ACP: acryl carrier protein
Triacrylglycerols &
phospholipids