Micro - Anabolism

Three phases of calvin cycle

carboxylation, reduction, regeneration

Carboxylation (calvin)

ribulose 1,5 bisphosphate ->3P glycerate by ribulose 1,5-bisphosphate carboxylase (RuBisCo) + CO2

Reduction (calvin)

3 P glycerate -> glyceraldehyde 3P

Regeneration (calvin)

regeneration of ribulose 1,5 bisphosphate carboxylase (RuBisCo)

What are the other possible pathways to fix CO2

reductive TCA cycle, 3-hydroxypropionate, and acetyl CoA pathway

Reductive TCA cycle

reverse of TCA, ATP -> ADP, 2 H+

3-hydroxypropionate

ATP + CO2 + 2H+

Acetyl CoA pathway

methanogens, CO2 -> acetyl CoA -> pyruvate -> biosynthesis

Gluconeogenesis

pyruvate -> glucose

P is needed for

nucleic acids, proteins, phospholipids, ATP

How is P assimilated

incorporated as inorganic P by formation of ATP (substrate level P, oxidative P, photoP)

Incorporation of organic P

phosphatases hydrolyze organic P esters to release inorganic O (can now be assimilated)

N is needed for

proteins, nucleic acids, coenzymes

How is N assimilated

as ammonia, nitrate reduction, reducing power

N2 gas incorporation

nitrogen fixation, nitrogen reduced to ammonia (by nitrogenase)

Ammonia incorporation

glutamate dehydrogenase catalyzes glutamate from a-ketoglutarate, transaminases transfer amino group to make proteins

Nitrate reduction

nitrate reduced to ammonia

S is needed for

amino acids, coenzymes

How is S assimilated

reduced to H2S

Purines

adenine and guanine

Pyrimidines

uracil, cytosine, thymine

Lipids synthesis

fatty acid synthesis, add acetyl CoA + malonyl CoA

Peptidoglycan synthesis

UDP binds to NAM, add alanine, now NAM-NAG, bactoprenol, antibiotics inhibit cell wall synthesis

Bactoprenol

hold amino acids together, transfer across cell membrane

Antibiotics to inhibit cell wall synthesis

cycloserine, vancomycin, bacitracin, penicillin

Cycloserine and vancomycin

inhibit addition of alanine -> inhibit cell wall synthesis -> osmotic lysis

Bacitracin

inhibits bactoprenol -> cant transfer or bind subunits -> no cell wall -> osmotic lysis

Penicillin

inhibit enzyme from making the crosslinks between peptidoglycan chains