Nitrogen Fixation Flashcards
Majority of nitrogen fixation
Bacteria
Industrial production
If too much nitrogen = aquatic dead zones
Types of plants and nitrogen need
Leaf = high need
Fruits = needs Phosphorus
Roots = needs potassium
Legumes = fixes nitrogen
Nitrate
No3
Ox is 5
Nitrite
No2
Ox is 3
Nitrogen
N2
Triple bond
Needs 6es to break down to ammonia
Ammonia
Nh3
Ox is -3
Nitrogen fixation
By bacteria
In plants = bacteria in roots
N2 to nh3
Needs
Mg, iron, atp, pyruvate,
Nitrogen fixing enzyme
Nitrogenase complex
Dinitrogenase reductase
= atp use, transfers es to Dinitrogenase usually from ferrodoxin
DiNitrogenase
=transfers 6e to nitrogen
=2e to form h2
Net reaction for nitrogen fixing
N2 + 8H+ + 8e- + 16ATP —> 2 NH3 + 16 ADP + H2 + 16 Pi
Pyruvate = e source
Leghemoglobin
Covers up bacteria and binds to o2 to prevent enzyme corruption
Assimilation
No2/no3 to nh3 by plants
Used for amino acids etc
Also uses Mo cofactors
NADPH es source
Glutamate structure reminders
5C
1 Nitrogen
Glutes = half of leg day = 5
Party on both ends = glute boys
Mate let me help you out!
Glutamine structure reminders
5C
2 nitrogen groups
Party on both ends
Glute = 5 bc half of leg day
Ya it’s mine!
The N group
Enzyme for glutamine synthesis
Glutamine synthetase
= 1 atp needed
Adds pi as leaving group when adding 2nd free nh3
Glutamine Synthesis Regulation
Cumulative feedback
= multiple inhibitors = need all present for complete shut down
= amp, tryptophan, carbamoyl phosphate, Ctp, histidine, glucosamine 6 phosphate
Also inhibited by alanine/ glycine = glutamate products sort of
How does atp regulate glutamine synthetase?
Covalent modification
= adenylated = p added by atp = deactivated
=deadenylation = p removed by ADP = activated
Types of non essential AA pathways
-PLP dependent transamination
-reduction
-amidation
-phenylalinine hydroxylase
-aminotransferase/ Phosphatase
Asparate source
Oxaloacetate
Glycine source
3 phosphoglycerate
Serine source
3 phosphoglycerate
Serene at sea = 3 letters = 3 carbons
Ine = Amine
Ser = a lot of o = on both ends
1 carboxyl
1 aldose
Glycine source
3 phosphoglycerate
Ine = amine group
Gly = 3 letters = 3 C
GlyCCC = only Cs
Glutamine source
Alpha keto glutarate
= alpha = party on both ends = glutes = 5
Ketose group
Direct Precursor to glutamate via PLP
PLP structure
Helps transfer amine groups by stabilizing enzyme cys w Schiff base
1 po4 group
N ring with 2 os = Alien looking branch with o
= P lip = big eyes
Asparagine source
Oxaloaectate
PLP pairs
Alpha keto glutarate and glutamate
Oxaloacetate and asparate
