Amino Acid Analysis, LC/MS
Urine
Performed by: Quest Diagnostics
Amino acid analysis is necessary for the diagnosis of a variety of inborn errors of metabolism. These include, but are not limited to:
- phenylketonuria,
tyrosinemia,
citrullinemia,
non-ketotic hyperglycinemia,
maple syrup urine disease,
and homocystinuria.
The assay is also key for the continued monitoring of treatment plans for these disorders and useful for assessing nutritional status of patients.
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Biomarkers included in this panel:
1-METHYLHISTIDINE
1-Methylhistidine is derived from the dipeptide anserine (which consists of the amino acids 1-methylhistidine and beta-alanine). Anserine and its derivatives are associated with the consumption of poultry and fish. Both 1-methylhistidine and 3-methyl
Learn more3-METHYLHISTIDINE
Both 1-methylhistidine and 3-methylhistidine are histidine metabolites which have been proposed as markers of meat intake. Note that some confusion exists in the literature regarding the numbering of atoms in the imidazole ring of histidine – 1
Learn moreAlanine is a nonessential amino acid. It is the second most abundant amino acid in circulation, after glutamine. It is found in many foods including eggs, meat, lentils, and fish. Alanine is involved in sugar metabolism for energy and is important in
Learn moreALPHA AMINO ADIPIC ACID
Alpha-aminoadipic acid (a-Aminoadipic acid) is an intermediary metabolite of lysine (primarily) and of tryptophan.
Learn moreALPHA AMINO BUTYRIC ACID
Alpha-Amino-N-butyric acid (α-ANB), also known as alpha-aminobutyric acid, is a nonessential amino acid derived from the catabolism of methionine, threonine, and serine. α-ANB is both formed and metabolized by reactions which require v
Learn moreARGININE
Arginine is found in all protein foods and is very abundant in seeds and nuts. It is considered a semi-essential amino acid during early development, infection/inflammation, or renal and/or intestinal impairment. It has many functions in the body inc
Learn moreASPARAGINE
Asparagine is a non-essential protein amino acid that is present in many fruits and vegetables including asparagus, from which it gets its name. Other dietary sources include meat, potatoes, eggs, nuts, and dairy. It can also be formed from aspartic
Learn moreASPARTIC ACID
Aspartic acid is a nonessential amino acid that plays roles in many important metabolic processes, such as energy production (citric acid cycle), hormone metabolism, CNS activation, and the urea cycle. It is found in many protein sources such as oyst
Learn moreBETA ALANINE
β-alanine is a breakdown product of carnosine and anserine, which are dipeptides from meat consumption. Although β-alanine’s properties are limited, its relationship to carnosine makes it important. Both have antioxidant properties. A
Learn moreBeta-aminoisobutyric acid (also known as 3-aminoisobutyric acid) is a non-protein amino acid formed by the catabolism of valine and the nucleotide thymine. It is further catabolized to methylmalonic acid semialdehyde and propionyl-CoA. Levels are con
Learn moreCITRULLINE
Citrulline is an intermediate, nonprotein-forming amino acid in the urea cycle serving as a precursor to arginine. It derives its name from the watermelon (Citrullus vulgaris), where it was first isolated and identified. It is easily absorbed by t
Learn moreCREATININE, RANDOM URINE
Creatinine is the endproduct of creatine metabolism. Creatine is present primarily in muscle and the amount of creatinine produced is related to total skeletal muscle mass. Daily creatinine production is fairly constant except when there is massive i
Learn moreCYSTATHIONINE
Cystathionine is an intermediate dipeptide within the process of transsulfuration. Transsulfuration is the main route for irreversible homocysteine disposal, glutathione production, and energy. The initial step involves the enzyme cystathionine &beta
Learn moreCYSTINE
Cystine is formed from the oxidation of cysteine, or from the degradation of glutathione oxidation products. It is two cysteines linked together with a disulfide bond.
Learn moreETHANOLAMINE
Ethanolamine is an intermediary metabolite in the serine-to-choline sequence. It can be used to synthesize phosphatidylethanolamine (PE), a very important membrane phospholipid. Ethanolamine is not only a precursor, but also a breakdown product of PE
Learn moreGAMMA AMINO BUTYRIC ACID
Gamma-aminobutyric acid (GABA) is an amino acid that functions as an inhibitory neurotransmitter. It serves one-third of brain neurons and is involved in depression and mania. Although there are some dietary supplement and food sources for GABA (cruc
Learn moreGLUTAMIC ACID
Glutamic acid is a nonessential amino acid is derived from the diet and from the breakdown of gut proteins. Glutamate is a major excitatory neurotransmitter in the brain. It plays a role in neuronal differentiation, migration, and survival in the dev
Learn moreGLUTAMINE
Glutamine is a nonessential amino acid and is the most abundant amino acid in the body. It is formed from glutamate using the enzyme glutamine synthetase. Approximately 80% of glutamine is found in the skeletal muscle, and this concentration is 30
Learn moreGLYCINE
Glycine is a nonessential amino acid that is synthesized from choline, serine, hydroxyproline, and threonine. It has many important physiologic functions. It is one of three amino acids that make up glutathione. Glycine’s dietary sources includ
Learn moreHISTIDINE
Histidine is a semi-essential amino acid which is formed in the breakdown of carnosine. Red meat is a common source of carnosine, and therefore histadine. Other food sources include poultry, fish, nuts, seeds, and grains. Histidine and hista
Learn moreHOMOCYSTINE
Homocystine is the oxidized form of homocysteine. A substance is oxidized when it undergoes the process of oxidation. I.e the addition of oxygen or any electronegative elements or the removal of hydrogen or any electropositive element. Homocy
Learn moreHYDROXYLYSINE
Hydroxylysine is an amino acid related to collagen. What is collagen? Collagen is the most abundant protein in your body. It is the major component of connective tissues that make up several body parts, including tendons, ligamen
Learn moreHYDROXYPROLINE
- Hydroxyproline is the key factor in stabilizing collagens. - Hydroxyproline is abundant in meat and low in plant-based foods. Meat intake increases levels of proline and hydroxyproline. - Increased hydroxyproline has been found in collagen ca
Learn moreISOLEUCINE
Branched Chain Amino Acids (Isoleucine, Leucine, Valine) are the three branched chain amino acids (BCAAs). Branched chain amino acids (BCAA) are essential amino acids and must be obtained from the diet (mainly meat, grains, and dairy).
Learn moreLEUCINE
Branched Chain Amino Acids (Isoleucine, Leucine, Valine) are the three branched chain amino acids (BCAAs). Branched chain amino acids (BCAA) are essential amino acids and must be obtained from the diet (mainly meat, grains, and dairy).
Learn moreLYSINE
Lysine is a nutritionally essential amino acid abundant in meat, fish, fowl, and legumes and is needed for formation of body proteins and enzymes. Lysine can be methylated using S-adenosylmethionine (SAM) to synthesize carnitine, which is needed f
Learn moreMETHIONINE
Methionine is an essential amino acid that plays an important role in the methylation cycle. Methionine is obtained from dietary intake or through homocysteine remethylation. Methionine’s dietary sources include eggs, fish, meats, Brazil nuts,
Learn moreORNITHINE
Ornithine is an intermediate nonprotein-forming amino acid of the urea cycle. Arginine is converted to ornithine via the arginase enzyme, with urea as a byproduct. Ornithine combined with carbamoyl phosphate is then converted into citrulline via the
Learn morePHENYLALANINE
Phenylalanine is an essential amino acid found in most foods which contain protein such as meat, fish, lentils, vegetables, and dairy. Phenylalanine is the precursor to another amino acid, tyrosine. Because tyrosine is needed to form several neurotra
Learn morePROLINE
Proline is a nonessential amino acid. It contains a secondary α-imino group and is sometimes called an α-imino acid. Proline, and its metabolite hydroxyproline, constitute a third of the total amino acids found in collagen. Lysine, pro
Learn moreSARCOSINE
Sarcosine is an amino acid made within the methylation cycle when S-adenosylmethionine (SAM) is conjugated with glycine. It can also be made by catabolism of dimethylglycine (DMG). There are many dietary sources of sarcosine including eggs, legume
Learn moreSERINE
Serine is a nonessential amino acid used in protein biosynthesis and can be derived from four possible sources: dietary intake, degradation of protein and phospholipids, biosynthesis from glycolysis intermediate 3-phosphoglycerate, or from glycine.
Learn moreTAURINE
Taurine differs from other amino acids because a sulfur group replaces the carboxyl group of what would be the nonessential amino acid, β-alanine. It takes part in biochemical reactions and is not fully incorporated into proteins. In most tissue
Learn moreTHREONINE
Threonine is an essential amino acid, i.e., it is vital for your health, but it cannot be synthesized by your body and therefore has to be obtained from a diet.
Learn moreTRYPTOPHAN
Tryptophan is involved in serotonin production via vitamin B6-dependent pathways resulting in the intermediate 5-hydroxytryptophan (5-HTP). 5-HTP is often used as a supplement for serotonin formation instead of tryptophan, which can be quickly met
Learn moreTYROSINE
Tyrosine is a conditionally essential amino acid which can come directly from the digestion of dietary protein. Common food sources include dairy, beans, whole grains, meat, and nuts. If intake is insufficient, tyrosine can be formed from the esse
Learn moreVALINE
Valine, together with Isoleucine and Leucine are essential amino acids and are collectively referred to as branched-chain amino acids (BCAAs).
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