6. AMINO ACID ANALYSIS Flashcards
What fasting duration is required before blood sample collection for amino acid analysis?
6 to 8 hours
What type of tube is used for blood sample collection in amino acid analysis?
Green top (heparin) tube
What must be done within 30 minutes of blood sample collection for amino acid analysis?
Deproteinization
At what temperature should samples be frozen if there is a delay in amino acid analysis?
−20°C to −40°C
What is the primary purpose of deproteinization in amino acid analysis?
Removal of proteins
What type of urine sample is preferred for quantitation in amino acid analysis?
24-hour urine sample preserved with thymol or organic solvents
What method is used for screening in amino acid analysis?
Thin-layer chromatography
What process separates ions and molecules based on their affinity to ion exchangers?
Ion exchange chromatography
What kind of exchangers attract positively charged ions?
Cationic exchangers
What kind of exchangers attract negatively charged ions?
Anionic exchangers
What technique separates ions based on electrophoretic mobility using voltage?
Capillary electrophoresis
Which method in amino acid analysis is highly specific and sensitive?
Tandem Mass Spectrometry (MS/MS)
What does MS/MS analyze by breaking down selected ions into fragments?
The chemical structure of precursor ions.
What is the consequence of enzyme deficiencies in inborn errors of metabolism?
Accumulation of precursor substances
What accumulates in phenylketonuria due to the deficiency of phenylalanine hydroxylase?
Phenylalanine and its metabolites
What are proteins composed of?
Polymers of amino acids linked covalently through peptide bonds
Where are most proteins synthesized?
Liver
Where are immunoglobulins synthesized?
Plasma cells
What are the primary elements found in proteins?
Carbon, oxygen, hydrogen, nitrogen, and sulfur.
What is the primary structure of a protein?
Linear sequence of amino acids
What determines a protein’s identity, functions, and molecular interactions?
primary structure.
What forms the secondary structure of a protein?
α-helices, β-pleated sheets, and bend conformations.
What adds strength and flexibility to proteins?
Secondary structure
What describes the overall shape or conformation of a protein molecule?
Tertiary structure
What structure results from the interaction of multiple protein subunits?
Quaternary structure
What is the process called when a protein loses its shape and function?
Denaturation
Name a cause of protein denaturation.
Heat, strong acids or alkali, enzymatic action, urea, ultraviolet light, or hydrolysis.
Name a protein that catalyzes chemical reactions.
Enzyme
Name a protein involved in glucose metabolism as a hormone.
Insulin, glucagon, growth hormone, or cortisol
Name examples of enzymes.
Phosphatases, dehydrogenases, and transaminases.
Name a transport protein.
Hemoglobin, albumin, or transferrin
What type of protein mediates the humoral immune response?
Immunoglobulins
What is an example of a structural protein?
Collagen, elastin, or keratin
Name an example of a storage protein.
Ferritin
Which protein helps maintain colloid osmotic pressure?
Albumin
What database is used for structural classification of proteins?
SCOP (Structural Classification of Proteins)
What is an example of a metalloprotein?
Ferritin
What is a nucleoprotein found in eukaryotic cells?
Chromatin
What is the basis for the Families of Structurally Similar Proteins (FSSP) database?
Three-dimensional protein structure
Name a globular protein
Albumin or hemoglobin.
Name a fibrous protein
Collagen or troponin
What is a metalloprotein, and give an example?
A protein with a metal ion; examples are ferritin and ceruloplasmin.
What is a glycoprotein, and give an example?
protein with carbohydrates; examples are haptoglobin and α-1-antitrypsin.
What is a nucleoprotein, and give an example?
A protein linked to nucleic acids; an example is chromatin.
