Amino Acid Metabolism Flashcards
(44 cards)
amino acids are the _____ of proteins
building blocks
some amino acids are converted into _______
acetyl-CoA
What is nitrogen fixation
conversion of N2 to NH3 or NH4+
how to leguminous plants incorporate nitrogen
from bacerially synthesized amino acids into their won
how to nonleguminous plants inorcporoate NH4+
NH4 produced by nitrogen fixing soil bacteria directly into amino acids via nitrogen assimilation
What are the two other nitrogen fixation processes that exist in the biosphere
industrial (the haber process) and atmospheric (lightning)
most often, NH4+ is incorporated into the amino acids ____ and ____
glutamate and glutamine
What are the key enzymes in nitrogen fixation and assimilation
nitrogenase complex, glutamine synthease, glutamate synthase, glutamate dehydrogenase
What does hte nitrogenase complex do
uses redox reaction and ATP hydrolysis to convert N2 and 2NH3 and six redox reactions
What does glutamine synthease do
found in all organisms, incorporates NH4 into glutamate to form glutamine in ATP-redox reaction
What does glutamate synthase do
found in bacteria works with glutamine synthease to replenish glutamate
what does glutamate dehydrogenase do
inconverts glutamate, NH4 and alpha-ketoglutarate using redox reactions
how many redox centers in the nitrogenous complex
six
which amino acids in infected plant cells are synthesized
Glu and Asp
What is the intermediate in the glutamate synthease reaction
y-glutamyl phoshpate
T or F: glutamate synthease reaction requrires ATP hydrolysis
T
What does NH4 assimilation require
glutamine synthease and lgutamate synthase
When can the glutamate dehydrogenase reaction assimilate NH4
when NH4 concentration are very high
degredation of eukaryotic cellular protein is mediated by _____ and ____
lysosomes nad proteases
How to lysosomes degrade proteins
contain acidic proteases that digest protein particles delivered by phagocytosis
how to proteases degrade proteins
using three different protease activities located within the central core
what is nitrogen used for in mammals
for urea or biosynthetic pathways
what happens to the remaining carbon skeletons in mammals
metabolized to create ATP, glucose, fatty acids or ketone bodies
amino acids transported to the liver use nitrogen to make _____
urea
