Anabolism: What microorganisms do with all that
1. Reducing power
2.Energy
3. Raw building materials
Reducing Power
NADH/FADHglycolysis and Kreb’s cycle
NADPH  oxidative photophosphorylation
NADPH  anaerobic photophosphorylation
1. Reverse electron flow
2. Protons from inorganic molecules (H2S, S2O3)
Protons leached from Fe-S containing molecules in PSI in
anaerobic photo-phosphorylation
Energy--ATP
1. Oxidation of organic molecules (glycolysis/Kreb’s cycle)
2. Electron transport:
A. oxidative phosphorylation (PMF) chemiosmosis)—
oxygen the final proton/electron acceptor
B. anaerobic– inorganic molecules final electron acceptor
3. Oxidation of inorganic molecules (usually fed into electron
transport chain)
4. Dissimulative reduction of inorganic molecules (CO2,
sulfides and iron
5. Oxidative and anaerobic photophosphorylation
Raw building materials
Carbon/Nitrogen/Phosphorous etc. from the catabolism of
carbohydrates
lipids
proteins
nucleic acids
strange organic matter such as petroleum
Carbon from CO2 fixation
Nitrogen from Nitrogen (N2) fixation
Etc.
Integrated pathway for catabolism and anabolism
CARBOHYDRATES
Ribose
Glucose
Phosphoglycerate
A.A
A.A.
LIPIDS
Phosphoenolpyruvate
Fatty
acids
Kreb’s cycle
A.A.
Pyruvate
oxaloacetate
Acetyl-CoA
NUCLEIC ACIDS
purines
pyrimidines
Amino
acids
succinate
Amino
acids
n.b. amino acids
(A.A)
Amino
acids
PROTEINS
a-keto
glutarate
One strange thing
bacteria can eat for
energy and
biomass—Petrol !!!
Mediated by oxygen and the
enzyme mono-oxygenase
variety of yeasts/ molds and
bacteria
Another strange thing—benzene/toluene
Requires oxygen, NADH. Aliphatic carbons are converted to linear
molecules that can be catabolized to succinate/Acetyl-CoA/pyruvate
which enter Kreb’s cycle—Pseudomonas spp.
CO2 fixation (Calvin cycle, reverse TCA
cycle and hydroxy-proprionate cycle)
How autotrophs reduce CO2 into
material they can use for biomass.
Calvin cycle
In: CO2, NADPH and ATP
Out: Fructose-6 phos
intermediate of glycolysis
Reverse TCA cycle
Hydroxy-proprionate cycle
Nitrogen fixation: atmospheric nitrogen to
fixed nitrogen that can be utilized by plants
and bacteria
Agricultural significance of nitrogen fixation:
Crop rotations with plants that form intimate symbiotic relationships
with Rhizobium spp. (bacteria in root nodules)
peas, beans, soybean, alfalfa, clover
Pre seed watery environments with cyanobacteria (Anabaena azollae)
and the water fern Azolla.
Plant rice as rice plants grow they crowd out and kill the water fern
thus releasing the nitrogen that they require
pgs 685-692 in text book