Amino Acid Metabolism Flashcards
True or False,
Proteins are a great source of energy from diet.
FASLE
L’utilisation des acides aminés comme source énergétique est très secondaire
Les acides aminés ne peuvent pas être mis en réserve dans
l’organisme
Components of an amino acid
alpha carbon
carboxylic end (COOH)
amine group (NH4)
cahine laterale (R)
What are zwitterions?
molécules avec charge + et – simultanées
like aminoacids that have a positive and negative charge
How many pKs can an a.a have? What about point isogenique?
2 pks (acid and base) sometime 3 based on the lateral chain
ONLY 1 point ISOGENIQUE = only one point of balance
Le pH auquel la charge nette de l’a.a. est zéro correspond au PI
What are 2 (3) essential amino acids and what does it mean?
Leucine + Lysine + Isoleucine = rhyme essential
Essential = need to get them from diet as we cannot synthesize them
True or False,
In times of protein surplus we are capable of storing amino acids for future use.
FASLE FALSE
Réservoir corporel d’acides aminés ≠ Entreposage
Contrairement au glucides et aux lipides, il n’y a pas d’entreposage
corporel en acides aminés.
Whatever a.a is not used to syntehsize proteins will be degraded
Where is azote corporel stored in?
protéines constituent le réservoir principal de l’azote corporel
What is balance azote and what does it mean?
The input and output of azote
The difference of secreted vs injested should be always 0 to mainteain a helthy a.a and protein pool
How to form glutamate via Transamination vs Amination?
What are the enzymes
Amination: an eznyme addsamine (NH5)
* Glutamate déshydrogénase
* Glutamine synthétase
Transamination: Échange d’azote entre un acide aminé et un acide a-cétonique
ALT
and
AST
What kind of molecule is NH4+ and what does it come from?
In the brakdown of amino acids (becasue they are not stored in the organism)
we will create products
Désamination creates NH4+ which is TOXIC
What is cycle alanine?
glycolyse dans les muscles
glucose -> pyruvate
pyruvate + NH4 -> Alanine
Alanine can either circulate in the system or go to the liver
if in the liver:
alanine -> pyruvate + Amine (NH4; urine)
pyruvate can become glucose again and the cycle continues
How to get glutamine from glutamate?
Gutamine synthetase
Glutamate + NH4 = Glutamine
Where do the amines (azote) come from in the cycle of ure?
The first one is in the mitochondria
The second azote comes from aspartate in the cytoplasm
deuxième azote pour la biosynthèse de l’urée est fourni par
l’aspartate
L’alanine et la glutamine sont libérées par de nombreux tissus et servent de ___________?
transporteurs de NH4 + vers le foie ou vers les rein
Les ions NH4 + d’origine _________ sont absorbés dans par
la veine porte et transportés vers le ___________.
intestinale (flore bactérienne)
foie
