Topic 5 Flashcards
Nitrogenase?
enzyme that converts N2 to NH3
How is NH3 used in cells?
used by cells as a nitrogen
source for building nitrogen containing molecules
Nitrogenase is comprised of two proteins called?
dinitrogenase & dinitrogenase reductase (use Fe/Mo cofactors)
Electrons come from …
Fe/S proteins
such as flavodoxin –> transferred to
dinitrogen reductase –> to dinitrogenase –> to N2.
Gluconeogenesis?
Producing glucose (for carbon/energy storage or as a precursor for biosynthesis)
T/F: Gluconeogenesis is the reversal of glycolysis.
TRUE (same steps in reverse)
Glucose is activated by …
addition of nucleotide diphosphates such as ADP-glucose, UDP-glucose
(using ATP, UTP)
Activated glucose form is used to produce polysaccharides for: (3)
- LPS (Gram negative outer membrane)
- NAM/NAG (peptidoglycan)
- Storage molecules like glycogen/starch – later used for carbon/ energy
What is Glutamate dehydrogenase and glutamine synthase used for?
- used to build nitrogen-containing molecules (e.g. amino acids)
- efficiently incorporate NH3 even at low levels
Role of Glutamine/glutamate?
act as nitrogen donors to produce many other key nitrogen-containing molecules in the cell
Fatty acids built 2 carbons at a time using by
adding _______ to growing
chain, therefore CO2 released as biproduct
malonyl-CoA(3 carbons)
ACP?
-stands for: acyl carrier protein
-“holder” of
substrates for fatty acid synthesis
Parts of a nucleotide?
pentoses (5C sugar, ribose) & nucleobases
Explain pentose phosphate pathway?
- generates ribose-5-phosphate from glucose-6-phosphate.
- generates NADPH and carbon skeletons
T/F: Purines (A/G) built using the same way as
pyrimidines (U/T/C).
FALSE: Purines (A/G) built using one pathway,
pyrimidines (U/T/C) produced separate pathway
What are the key intermediates of purines and pyrimidines used to produce final products?
IMP for purines
Orotate for pyrimidines
What are the metabolic requirements for all life? (4)
- liquid water
- source of energy to do work
- nutrients
- source of electrons for biochemical rxns
How is energy conserved in microbes?
- storing it in high energy molecules aka ATP
Metabolism
series of biochemical reactions needed for life
Catabolism
hint: cata reminds me of cut so…
- reactions used to get energy by breaking down complex molecules
Anabolism
reactions used to synthesis cellular material (energy)
Chemotrophs
- get energy by breaking down high energy molecules to low energy
Phototrophs
use energy from the sunn!!
Autotrophs vs Heterotrophs?
autotrophs use CO2 (producers/plants)
- most are chemolithotrophs or phototrophs
heterotrophs get carbon from organic molecules
- mostly chemoorganotrophs