Protein Flashcards
Structure of an amino acid
a central carbon with an amino, carboxyl, hydrogen and R-group attatched to it
- the R group is the defermining factor of the Amino Acid
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peptide bond
the bond between the carboxyl group and and the Amino group of another
- takes a chain of 40 AA to be considered a protein
Phenylketoneuria
- autosomal recessice phenylalanine accumulates
- pregnant women are have resticted diet to prevent mental retardation
- neonatal screening is preformed
tyronseinuria
disorder of tyrosine catabolism
- leads to liver damage, cirrosis, liver cancer
- can cause maple syrup disease where there is an enzyme defect leading to the accumulation of leucine, isoleucine and caline in the blood, urine and CSF
- causes sweet smelling urine
homocystinuria
intermediate in amino acid synthesis of cystine from methionine
- enzyme impairment causes elevated levels
cystinuria
due to abnormal in renal tubulue reabsorbative mechanism
- leades to cyctine calculi
bence-jones proteinura
light chains in urine, concentrations exceed kidney tubule threshold
- single clone plasma cell producing Ig quantities of identical free light chains
- free and light chains dectected at ALI
Prealbumin
- retinol-binding protein
- is decreased in: hepatic damage, acute inflammatory responses and tissue necrosis
- is a sensitive marker of poor protein nutritional status
- increased in patients receiving steroids
- measured by nephometry and turbimetry
albumin
most abundant protein
- is small (60,000Kdaltons)
- major protein component of extra vascular body fluids
- is an indicator of glumerular integrity
- it maintains colloidal osmotic pressure of intravascular fluid
- transports: bilirubin, fatty acids, toxic heavy metals, drugs, dyes….
- can cause edema ( when below 2.5g/dL)
- negative phase reactant(decreases with inflammation)
hypoalbuminemia
impaired synthesis
- decreased protein intake
- increase catabolism
- protein loss due nephrotic syndrome
A1- antitrypsin
acute phase reactant
- inhibitor of the proteolytic enzyme elastase
- neutralizes enzymes
- up 20 90% of alpha band
- 90 alleles identified
- four groups: normal, null(nondetectable), deficient (<35% average normal level), dysfunctional(normal quantity but not functional)
- disease is due to decreased, increased, and presents with COPD
a1-feroprotein
glycoprotein, produced early, increased in maternal AFP when the mothers fetus suffered from failed closure of the renal tubule
- decreased in downsyndrom
- can be seen in germ cell tumors and hepatocellular carcinoma
hapatoglobin
synthesized in the liver, acute phase reactant
- binds to the free hemoglobin in the serum
- irreversibly binds to oxyhemoglobin in plasma
- is removed from plasma by reticuloendothelial system
- conversion wit intravascular hemolysis
- combines with beta 1 globin, hemopexin, albumin
ceruloplasmin
- late acute phase reactant
- carries plasma copper (6 molecules)
- enzyme function
- catalyzes oxidation of FeII to FeIII
- wilsons disease
- defect in copper metabolism, hepatolenticular degeneration
- leads to liver, spleen and brain damage
- increased during pregnancy and estrogen administration
Transferrin
synthesized in the liver, transports iron to storage and the bone marrow
- densly packed receptors in erythroid precurusors, hepatocytes and placenta cells.
- is recycles and reused
- increased transferrin is regulated by the availibilty of iron, decrease can lead to increase???
- decrease: negative phase reactant, inflammation
- circulating normally 1/3 saturated
- saturation can be decrased in iron deficiency anemia or increased in iron overload or liver disease
