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AZOTO C, H, N, O compongono 96 del materiale
vivente 78 aria (in peso) secondo elemento
piu abbondante nel corpo umano
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• Fissazione dellazoto di tipo biologico
• Batteri simbionti (associati alle radici delle
  leguminose)
• Rhizobium
• Batteri liberi nel suolo (Azotobacter)
• arricchimento di azoto (NH4) nel terreno

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NITRIFICAZIONE conversione ammonio ?
nitrato ossidazione in terreni
aerati Nitrosomonas NH3 ? NO2- Nitrobacter NO2-
? NO3-
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AMMONIFICAZIONE conversione nitrato ?
ammonio Nitrato azoto biodisponibile per
eterotrofi (aa e acidi nucleici) Azione dei
funghi decompositori
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DENITRIFICAZIONE conversione nitrato ? azoto
N2 Pseudomonas
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• Did you know?
• That most of the air we breathe is made by
  anammox bacteria?
• That anammox bacteria divide only once per two
  weeks at maximum speed?
• That hydrazine (rocket fuel) and nitric oxide are
  the anammox intermediates?
• That these intermediates are turned over in an
  organelle surrounded by an impermeable membrane
  made of ladderane lipids?
• That anammox bacteria share a common ancestor
  with the parasitic chlamydia?
• That you can download the anammox genome HERE?

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Partial nitrification/Anammox is a new method
for nitrogen removal from wastewater. It targets
wastewater streams (or gases) high in ammonium
(gt0.2 g/l) and low in organic carbon (CN ratio
lower than 0.15). The two processes proceed as
follows
(partial nitrification) 2NH4 1.5O2 gt NH4
NO2- H2O 2H (anammox) NH4 NO2- gt N2
2H2O
(total) 2NH4 1.5O2 gtN2 3H2O 2H
(the produced acid is balanced by the counter-ion
of ammonium, usually bicarbonate or sulfide)
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STECHIOMETRIA 1 NH4 1.32 NO2- 0.066 HCO3-
0.13 H 1.02 N2 0.26 NO3- 0.066
CH2O0.5N0.15 2.03 H2O Optimum 6CltTlt43C 6.7ltp
Hlt8.3 DOlt0.5 NO2- lt20mM
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anammox process is based on energy conservation
from anoxic ammonium oxidation with nitrite as
the electron acceptor and hydrazine as the
intermediate. CO2 is used as the main carbon
source for growth. Recently we learned that CO2
fixation is accomplished via the acetyl-CoA
pathway. The necessary electrons are obtained
from the anaerobic oxidation of nitrite to
nitrate
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anammox mechanism with hydrazine and nitric
oxides as intermediates reversed electron
transport to upgrade electrons from nitrite
oxidation to drive anammox carbon fixation via
the acetyl CoA pathway
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planctomycetes
They lack the otherwise universal bacterial cell
wall polymer peptidoglycan, they divide by
budding, and they have a differentiated
cytoplasm.. They are separated from other
bacteria and amongst themselves by large
evolutionary distances. Other species of
planctomycetes are aerobic chemoorganoheterotrophs
, very different from the anammox bacteria

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The first full scale anammox reactor, Rotterdam,
the Netherlands. It works at design load and
removes over 500 kg N/day