Protein Handbook For Beginners: Protein & The Amino Acid Connection.

Protein, whether from your own tissues (e.g. muscle), from whole foods or from supplements, all consists of amino acids ... Learn more about those aminos right here.
Jump To:


2. Protein & The Amino Acid Connection.


Protein & The Amino Acid Connection:

    Protein, whether from your own tissues (e.g. muscle), from whole foods or from supplements, all consists of amino acids linked together in chains called peptides or polypeptides.

    Amino acids aid in repair, growth and development of muscle tissue (which is why amino acids are called the building blocks of protein), and also do a lot more. The body, through assimilation of amino acids, produces over 50,000 proteins and over 15,000 enzymes that have far reaching effects in the body.

    In addition to aiding in the repair, growth and development of muscle tissue amino acids can normalize moods, improve concentration, attention, sleep, sex drive as well as producing chemicals that enable our brains to function properly (e.g., dopamine, glycine, GABA and glutamate).

    Other biologically-important roles amino acids play include: lipid transport within cells (carnitine), the disposal of excess nitrogen (ornithine), synthesization of other molecules (tryptophan is a precursor of the neurotransmitter serotonin), etc.

    More than 100 amino acids have been found in nature. In addition to protein synthesis, amino acids have other biologically-important roles. Of these amino acids 20 are considered "standard amino acids" because they are encoded by the standard genetic code. The 20 "standard amino acids" are separated into two categories - essential and non-essential.

    The Essential Amino Acids Include:

    The Non-Essential Amino Acids Include:

    Essential aminos cannot be produced by the body and must be made available through the diet. Non-essential amino acids can be produced by the body within the liver. The correct ratios of essential and non-essential amino acids must be present in sufficient quantities before any muscle can be produced.


Branched-Chain Amino Acid (BCAA)s:

    Branched-chain amino acids are considered essential amino acids because they are essential to life and because the body can not manufacture its own branched-chain amino acids. Branched-chain amino acids make up 35-40% of the essential amino acids in body protein and approximately 15 of the total amino acids in skeletal muscle.

    In humans, about 20% of total protein intake is typically branched-chain amino acids, with most coming from dairy product sources. The branched-chain amino acids are leucine, isoleucine and valine. Branched-chain amino acids are metabolized in the muscle, rather than in the liver and must be supplied through the diet.

RELATED ARTICLE
Branch-Chained Amino Acids: More Than Just Amino Acids? Branch-Chained Amino Acids: More Than Just Amino Acids?
The idea of supplementing with extra BCAA's in addition to ones protein intake has been around for some time. It is time to take an in depth look at BCAA's.
[ Click here to learn more. ]

    Branched-chain amino acids must be present in the diet for the maintenance of muscle tissue and play important roles in promoting protein synthesis via multiple pathways, and increases the production of other amino acids such as glutamine.

    Studies also show branched-chain amino acids are important for muscle growth, recuperation and for fighting fatigue. Branched-chain amino acids preserve muscle tissue during high intensity exercise. They can provide as much as 15% of your total energy during extended workouts. By ensuring adequate amount of branched-chain amino acids in your body, both before and after training, will delay fatigue, guards against training-induced muscle breakdown and expedite recovery.


The "Nonstandard Amino Acids":

    Aside from the 20 standard amino acids discussed above there are a vast number of "nonstandard amino acids." The "nonstandard amino acids" are usually formed through modifications to standard amino acids (e.g. dopamine synthesized from tyrosine, taurine can be formed by the decarboxylation of cysteine, etc.).

    The "nonstandard amino acids" also have many different important functions within the body (e.g. GABA and dopamine are neurotransmitters, ornithine and citrulline provide important functions in the urea cycle, etc.).

    What Is The Urea Cycle:
    The sequence of chemical reactions that takes place in the liver and that results in the production of urea. The key reaction is the hydrolysis of arginine by arginase to ornithine and urea. Also called Krebs-Henseleit cycle, Krebs ornithine cycle, Krebs urea cycle.

    They are also used for medicinal purposes (e.g., 5-hydroxytryptophan [5-HTP]) is phenylketonuria, depression and sleeping disorders associated with low serotonin levels; L-dihydroxyphenylalanine (L-DOPA) is used as a drug used to treat Parkinson's Disease, etc.).

Jay & Jeff
Click Image To Enlarge.
Jay Cutler & Jeff Behar.


Take Protein Quiz #2!

PROTEIN QUIZ #2
 Pick The Most Appropriate Answers, Then Click "Calculate".
1. True Or False: The Body, Through Assimilation Of Amino
    Acids, Produces 15,000 Proteins & 50,000 Enzymes That Have
    Far-Reaching Effects In The Body.
A. True.
B. False.
2. True Or False: Proline Is An Essential Amino Acid.
A. True.
B. False.
3. True Or False: L-Dihydroxyphenylalanine (L-DOPA) Is Used
    To Treat AIDS Patients.
A. True.
B. False.

   
Answers Will Display Here After Pressing "Calculate".

NAVIGATION:
Back
[ Back ]
Home
[ Home ]
Next
[ Next ]