Proteins Flashcards
provides ___ of daily body energy
12-20%
___ of a cell’s dry weight
50-70%
+ and - acute phase reactants
+ = increase in concentration // -= decrease in concentration (inflammation)
linear sequence of amino acids
primary structure
determines the identity of proteins
primary structure
Winding of polypeptide chain. Refers to the
specific 3D configuration of the ɑ-helix and
β-pleated sheets (bent form)
secondary structure
Actual 3D configuration of proteins or the
folding pattern of protein
tertiary structure
Responsible for many of the physical and
chemical properties of the protein
tertiary structure
Association of two or more polypeptide chain to form a functional protein molecule
quaternary structure
Albumin does not have a _____, it is a ______
quaternary, single polypeptide chain
Catalyzes chemical reactions
enzymes
Chemical messengers that control the action
of specific cells or organs
hormones
Affect the growth, metabolism, and
development of the body
hormones
Transport movement of ions, small
molecules, or macromolecules across a
biological membrane
transport proteins
Immunoglobulins are produced by _________ in the
___________ that mediate the humoral
immune response to identify and neutralize
foreign objects.
B cells (lymphocytes), bone marrow
storage form of iron
ferritin
plasma proteins that function in the
distribution of water throughout the
compartments of the body
osmotic force
contains peptide chain of amino acid
simple proteins
Symmetrical, water soluble
globular protein
Transporter enzyme and
hormone/messenger
globular protein
examples of globular protein
albumin, hemoglobin,
immunoglobulin
Long filament, asymmetrical, usually
inert
fibrous protein
Water insoluble
fibrous protein
Provides structure to the
cell
fibrous protein
examples of fibrous protein
fibrinogen, troponin,
collagen
consists of protein and a
non-protein group
conjugated proteins
examples of metalloproteins
– ferritin, ceruloplasmin,
hemoglobin, flavoproteins
examples of glycoprotein
haptoglobin, α1-antitrypsin
(10-40% CHO)
examples of lipoproteins
VLDL, LDL, HDL, Chylomicrons
examples of mucoproteins
mucin
examples of nucleoprotein
chromatin
Most commonly analyzed protein
plasma proteins
Generally function as transporter
albumin group
Groupings are based on _____
depending on their migration on the electrophoresis
electrophoretic mobility
Maintains osmotic pressure and as an amino acid
reserve
albumin group
Aka Transthyretin
pre albumin
Migrates before albumin in electrophoresis
pre albumin
Indicator of nutritional status
pre albumin and albumin
Binds thyroid hormones and retinol
pre albumin
Used to confirm the specimen is CSF
pre albumin
half life of pre albumin
2 days
increased prealbumin
alcoholism, chronic renal failure, steroid
treatment
decreased prealbumin
poor nutrition
Reference value and CF of prealbumin
18-45 mg/dL (CF to mg/L: 10)
electrolytes transported by albumin
Ca, Mg, Fe
The most abundant protein in plasma
albumin
decreased in albumin
inflammation, liver disease, renal disease
of albumin is synthesized by the liver per day
9-12g
reference value and CF of albumin
3.5-5.0 g/dL (CF: 10)
albumin conjugates with (4)
bilirubin, thyroid hormones, aspirin, fatty acids
Included in assessing the synthetic function
of liver
albumin
Sensitive and prognostic marker of cystic
fibrosis
albumin
Indicator of short-term hyperglycemic
control
albumin
Compensate to the loss of albumin resulting to
normal level of total protein
globulin group
Most abundant protein (__%)
in the α1-globulin band
a1-antitrypsin, 90%
Major inhibitor of protease
activity
a1-antitrypsin
Neutralizes trypsin-like
enzymes
a1-antitrypsin
the primary neutrophilic granule that
combats infection but may also destroy pulmonary alveoli
resulting to emphysema
neutrophil elastase
increased a1-antitrypsin
inflammation,
pregnancy and contraceptive
use
decreased a1-antitrypsin
emphysema,
juvenile hepatic cirrhosis,
SERPINA1 gene mutation
reference value and CF of a1-antitrypsin
145-270 mg/dL (CF to g/L: 0.01)
Migrates between albumin and
α1 globulin band
a1-fetoprotein
a1-fetoprotein is synthesized by the ____ and then by the fetal
______ of the liver
fetal yolk sac, parenchymal cells
a1-fetoprotein is normally detected in maternal
serum during the _______
of pregnancy
7-8th month
methods of a1-fetoprotein
immunochemical
test, Radioimmunoassay,
Enzyme Linked immunoassay
increased a1-fetoprotein
Maternal serum (twin
fetus)
Peaks in fetus at 13th
week of gestation
Serum: hepatoma
(>1000 ng/mL)
Gonadal cancer
gestational marker for
neural tube defect, spina
bifida, and fetal distress
a1-fetoprotein
decreased a1-fetoprotein
Down
Syndrome, Edward’s syndrome
reference value of a1-fetoprotein
5 ng/mL
Aka Orosomucoid
a1-acid glycoprotein
Contains high levels of
carbohydrates (__%) and sialic
acid (____%)
a1-acid glycoprotein, 45%, 11-12%
Major plasma glycoprotein
a1-acid glycoprotein
Diagnostic tool for neonatal
bacterial infections
a1-acid glycoprotein
Binds progesterone and
quinidines
a1-acid glycoprotein
increased a1-acid glycoprotein
pregnancy, cancer,
pneumonia, AMI, RA and cell
proliferation
methods for a1-acid glycoprotein
Radial
immunodiffusion,
immunoturbidity,
nephelometry, immunofixation
reference value and CF of a1-acid glycoprotein
50-120 mg/dL
(CF to g/L: 0.01)
Member of the serine protease
inhibitor (serpin) family
a1-antichymotrypsin and inter-a-trypsin inhibitor
Binds and inactivates prostate
specific antigens
a1-antichymotrypsin
Pathognomonic of Alzheimer’s
disease
a1-antichymotrypsin
Integral component of the
amyloid deposits in Alzheimer’s
disease
a1-antichymotrypsin
increased in a1-antichymotrypsin
infection,
malignancy, burn, AMI,
Alzheimer’s disease
decreased in a1-antichymotrypsin
: liver disease
reference value and CF of a1-antichymotrypsin
: 30-60 mg/dL
(CF to g/L: 0.01)
Plays an important role in
inflammation and
carcinogenesis.
inter-a-trypsin inhibitor
increased in inter-a-trypsin inhibitor
inflammatory
disorders
Indirect marker for
atherosclerosis
a-lipoprotein
a-lipoprotein - Increased ( ____mg/dL):
________
Decreased ( mg/dL): _______
≥65, cardioprotective // <35, risk for
chronic heart disease, acute
myocardial infarction
main function of Gc globulin
Vitamin
D-binding protein
method of Gc globulin
radial
immunodiffusion
It is the major carrier protein
for Vitamin D and its
metabolites
Gc globulin
Transports fatty acids and
endotoxins
Gc globulin
Migrates towards the α1 and α2
bands (EPS)
Gc globulin
increased in Gc globulin
pregnancy (3rd
trimester), oral contraceptives
(estrogen)
decreased in Gc globulin
liver disease
reference value and CF of Gc globulin
20-55 mg/dL
(CF to g/L: 0.01)
A tetramer
haptoglobin
Binds free hemoglobin by its α chain
haptoglobin
marker for intravascular hemolysis
haptoglobin
Marker to evaluate rheumatic disease
haptoglobin
increased in haptoglobin
stress,
myoglobinuria
decreased in haptoglobin
Intravascular
hemolysis,
hemoglobinuria
methods of haptoglobin
radial
immunodiffusion,
immunonephelometry
reference value and CF of haptoglobin
26-185
mg/dL (CF to g/L: 0.01)
Copper-binding glycoprotein
ceruloplasmin
Synthesized by the liver where 6-8
atoms of copper are attached
ceruloplasmin
Marker for Wilson’s Disease
ceruloplasmin
deposition of copper in cornea
Kayser Fleisher rings
increased in ceruloplasmin
inflammation,
cancer, pregnancy
decreased in ceruloplasmin
Wilson’s
disease, malnutrition,
malabsorption, nephrotic
disease, Menkes’
Syndrome
(kinky hair)
reference value & CF of ceruloplasmin
18-45
mg/dL (CF to mg/L: 10)
method for ceruloplasmin
Copper oxidase
activity
largest major non-immunoglobulin
a2-macroglobulin
proteases inhibited by a2-macroglobulin
trypsin, thrombin,
kallikrein, plasmin
Forms a complex with PSA
a2-macroglobulin
Removed by reticuloendothelial system after inhibiting proteases
a2-macroglobulin
reference value and CF of a2-macroglobulin
150-420
mg/dL (CF to g/L: 0.01)
increased in a2-macroglobulin
Nephrosis (10x),
Pregnancy (20%),
Diabetes, Liver disease,
Contraceptive medication
methods for a2-macroglobulin
radial
immunodiffusion,
immunonephelometry,
ELISA and latex
agglutination
proteins in a1 globulin group
a1-antitrypsin, a1-fetoprotein, a1-acid glycoprotein, a1-antichymotryspsin, inter-a-trypsin inhibitor, a-lipoprotein, Gc globulin
a2 globulin group
haptoglobin, ceruloplasmin, a2-macroglobulin
proteins in b2 globulin group
hemopexin, b2-microglobulin, transferrin, fibrinogen, complement, c-reactive protein, pre-b-lipoprotein, b-liporotein, immunoglobulins
binds heme released by degeneration of hemoglobin
hemopexin
reference value & CF of hemopexin
50-120 mg/dL (CF: 0.01)
increased in hemopexin
inflammation, diabetes, duchenne-type muscular dystrophy, melanoma
decreased in hemopexin
urinary loss, decrease liver synthesis, hemolytic anemia, intravascular hemolysis
light chain component in the major histocompatibility complex or human leukocyte antigen
b2-microglobulin
found in the surface of most nucleated cells
b2-microglobulin
found in high level concentration in lymphocytes
b2-microglobulin
important in the production of CD8 cells
b2-microglobulin
freely filtered by the glomerulus and absorbed & metabolized in the proximal tubules in the kidneys
b2-microglobulin
increased _______ in plasma is due to impaired clearance in the kidneys
b2-microglobulin
tends to fold into b-sheet configuration
b2-microglobulin
increased in b2-microglobulin
renal disease, multiple myelomas, RA, SLE, HIV
method for b2-microglobulin
immunoassay
reference value for b2-microglobulin
0.2 - 2.8 ug/dL
negative acute phase reactants
albumin and transferrin
major b-globulin protein
transferrin
other name of transferrin
siderophilin
transports iron back to its storage site (___)
transferrin, bone marrow
increased level of transferrin in plasma appears as ___ (__) and is seen in severe IDA
paraprotein (pseudoparaproteinemia)
decreased level of transferrin can impair _____ and can lead to _____
hgb production, anemia
increased transferrin
hemochromatosis (bronze diabetes), IDA
decreased transferrin
liver disease, malnutrition, nephrotic syndrome
methods for transferrin
immunodiffusion, immunonepehelometry
reference value for transferrin
Male: 215-365 mg/dL // Female: 250-380 mg/dL // CF: 0.01
other name for fibrinogen
clotting factor I
one of the largest proteins in the blood
fibrinogen
most abundant coagulation factor
fibrinogen
marker for long term prognosis of cardiovascular disease
fibrinogen
increased fibrinogen
inflammatory disorders, pregnancy, contraceptive medication
decreased fibrinogen
extensive coagulation
reference value and CF for fibrinogen
200-400 mg/dL (0.01)
natural defense mechanism against infection
complement
ciruclates in inactivated form
complement
most abundant complement in serum
C3
important in macular degeneration
C3
most commonly measured complement protein
C3 AND C4
increased in complement
inflammation
important in assessing RA and SLE
C4 & C4
decreased in C3
autoimmune disorders, neonatal respiratory distress syndrome, bacteremia, tissue injury, chronic hepatitis
decreased in C4
disseminated intravascular coagulation, acute glomerulonephritis, chronic hepatitis, hemolytic anemia, malnutrition
method of complement
immunonephelometry, turbidimetry
member of the pentaxin protein family
C-reactive protein
most popular acute phase reactant
C-reactive protein
name is derived for the ability to precipitate C-substance of pneumococci
C-reactive protein
known as a scavenger molecule
C-reactive protein
gamma-migrating protein
C-reactive protein
early cardiac marker
C-reactive protein
used as a rapid test and presumptive diagnosis of bacterial or viral infection
C-reactive protein
determines the severity of CHD
C-reactive protein
undetectable in healthy specimen, but is present in diverse inflammatory disease
C-reactive protein
increased in C-reactive protein
acute rheumatic fever, myocardial infarction, RA, gout, bacterial & viral infection
reference value of C-reactive protein
> 1.0 mg/dL
transports TAG from liver to peripheral tissues
pre-b-lipoprotein
transports cholesterol from liver to peripheral tissues
b-lipoprotein
most atherogenic lipoprotein
b-lipoprotein
reference values for b-lipoprotein
Optimal: <100mg/dL // Above optimal: 100-129 mg/dL // Borderline: 130-159 mg/dL // High: 160-189 mg/dL // Very high: > _190mg/dL
the only protein synthesized by plasma cells
immunoglobulins
most abundant, found in plasma and lymph nodes
IgG
found in mucous secretions
IgA
1st to appear in resposnse to antigenic stimulation
IgM
found in the surface of B cells
IgD
associated with allergy and anaphylactic shock
IgE
composition of immunoglobulins (%)
82-96% protein // 4-18% CHO
gamma spike is seen in?
multiple myeloma, immunoglobulins
decreased immunoglobulins
HIV and other immunodeficiences
method for immunoglobulins
nephelometry, turbidimetry, radial immunodiffusion, immuno assay
primary oxygen-carrying protein
myoglobin
what are the cardiac proteins
myoglobin, troponin, b-type natriuretic peptide
myoglobin is found in
cardiac and skeletal muscle
myoglobin carries ___% of total muscle protein
2%
myoglobin transports and stores oxygen from ____ to the intracellular respiratory enzymes of the ________
hgb, contractile cells
earliest marker for myocardial infarction
myoglobin
rise of myoglobin
1-3hrs
peak of myoglobin
5-12hrs
troponin is found in
skeletal muscle
normalize of myoglobin
18-30 hrs ave. 24 hrs
transporter of actin and myosin
troponin
method of troponin
immunoassay
screening test for myocardial infarction (____)
myoglobin, >100 ug/mL
myoglobin may cause false positive in urine strip and Hgb during ______ due to its ______
myoglobinuria, pseudoperoxidase activity
myoglobin increased
AMI, rhabdomyolysis, angina, muscular trauma, intramuscular injection, strenous exercise, acute renal failure
method of myoglobinuria
immunoassay
other name of troponin T
troponin-binding subunit
other name of troponin I
inhibitory subunit
other name of troponin C
calcium-binding subunit
troponin that regulates muscle contraction
troponin c
troponin that is cardiac specific and sensitive
troponin i
troponin that is not cardiac specific
troponin c
troponin i is found in
myocardium
troponin that is absent in normal serum
troponin i and t
troponin t is found in
fetal and deceased skeletal muscle
sensitive marker for diagnosis of unstable angina
troponin t
_____ - suggestive of AMI
> _1.5 ng/mL
rise, peak, normalize of troponin t
3-4hrs, 10-24hrs, 7 days
rise, peak, normalize of troponin i
3-6hrs, 12-18hrs, 5-10 days
popular marker for congestive heart failure
b-type natriuretic peptide
increases in response to peptide ventricular systolic and diastolic dysfunction
b-type natriuretic peptide
half life of b-type natriuretic peptide
60-120 minutes
methods for b-type natriuretic peptide
RIA, microparticle enzyme immunoassay, ECLIA
reference value of b-type natriuretic peptide
<100pg/mL
other name for renal proteins
cystatin c
alternative for creatinine and creatinine clearance test to screen and monitor kidney dysfunction
renal proteins
a cysteine proteinase inhibitor
renal proteins
new sensitive endogenous serum marker for glomerular filtration rate
renal proteins
not affected by age, diet, gender, or muscle mass
renal proteins
increased in renal proteins
renal disease
what are the renal proteins
urinary proteins, microalbuminuria, csf protein, csf oligoclonal banding
methods for renal proteins
particle-enhanced immunoturbidimetry, immunonephelometry
most urinary proteins are from the ____
blood
normal albumin excretion rate
<20 ug/min
most common and serious type of proteinuria
glomerular proteinuria (albuminuria)
appearance
of low molecular weight proteins
in urine due to defective
reabsorption with slightly
increased urine albumin excretion
rate
tubular proteinemia
positive albumin dipstick value
> _6.0 mg/dL
hemoglobinuria, myoglobinuria,
and Bence-Jones Proteins
overload proteinemia
protein
from the urinary tract caused by
infection, bleeding, or malignancy
postrenal proteinemia
Early indicator of glomerular
dysfunction
microalbuminuria
Nephropathy associated with
Type 1 DM
microalbuminuria
positive for microalbuminuria
2 out 3 specimens collected
within 3-6 months
physiologic increase for microalbuminuria
physical exercise during the previous 24 hours
specimen for microalbuminuria
random urine
increased in microalbuminuria
diabetic nephropathy,
fever, infection and hypertension
method for microalbuminuria
random-spot
albumin-creatinine ratio
reference value for microalbuminuria
0-29 μg/mg creatinine
Microalbuminuria: 30-300
μg/mg creatinine.
Clinical albuminuria: >300
μg/mg creatinine
an ultrafiltrate of plasma
formed in the choroid plexus
of the ventricles of the brain
CSF
method for CSF protein
TCA, SSA, Coomassie
Brilliant Blue (dye), Lowry and
Kinetic Biuret Reaction
decreased in CSF protein
intracranial
hypertension, hyperthyroidism,
CSF leakage due to trauma
reference value of CSF protein
15-45 mg/dL
reference value of CSF albumin
10-30 mg/dL (2/3 of
CSF total protein)
Presence of 2 or more IgG
bands in the γ region
CSF Oligoclonal banding
Seen in multiple sclerosis (90%)
CSF Oligoclonal banding
(+) result for CSF Oligoclonal banding
≥ 2 bands in
the CSF not present in serum
other disorders with 2 or more bands in the CSF
Encephalitis, neurosyphilis,
Guillain-Barre syndrome,
neoplastic disorders
supporting medium & stain for CSF Oligoclonal banding
Agarose gel & Coomasie Brilliant
Blue
Disorders with serum banding
appearing in CSF
Leukemia, lymphoma, viral
infection
Detected in newborn screening
aminoacidopathies
what is absent in alkaptonuria
homogentisate-1,2-dioxygenase
diagnostic indicator of alkaptonuria
darkening
of urine upon standing at RT
clinical feature of alkaptonuria
ochronosis
(tissue pigmentation)
what is absent in homocystinuria
cystathionine Β-synthase
what is absent in Maple Syrup Urine Disease
α-keto
acid decarboxylase
screening test & antagonist of homocystinuria
Modified Guthrie Test (Lmethionine sulfoximine – antagonist)
Result from accumulation of
branched-chain amino acids such as
leucine, isoleucine, & valine
clinical features of homocystinuria
physical
defects, thrombosis,
osteoporosis, islets
abnormalities, and mental
retardation
screening test & antagonist of Maple Syrup Urine Disease
Modified Guthrie Test (4-azaleucine – antagonist)
diagnostic test for Maple Syrup Urine Disease
amino acid analysis (HPLC)
indicator of Maple Syrup Urine Disease
4 mg/dL leucine – indicative of MSUD
clinical feature of Maple Syrup Urine Disease
failure to thrive,
muscular rigidity, mental
retardation, hypoglycemia
what is absent in Phenylketonuria
phenylalanine hydrolase
(PAH) / phenylalanine-4-
monooxygenase
reference value of PKU
1.2-3.4 mg/dL (70-200 umol/L)
PKU displays increased concentration
of primary metabolite
(_______) in both
blood & urine
phenylpyruvic acid
odor of PKU urine
Musty odor urine
screening test for PKU
Guthrie
Bacterial Inhibition Assay
(Bacillus subtilis spores
& β2-thienylalanine -
antagonist)
positive result for screening test of PKU
Bacterial
growth (phenylalanine
>4 mg/dL)
Tyrosinemia 2
Tyrosine
aminotransferase
Tyrosinemia 3
4-hydroxyphenylpyruvic
acid dioxygenase
Tyrosinemia 1
Fumarylacetoacetate
hydrolase/FAA
hydrolase
Tyrosinemia is accompanied by
increased
level in the blood of methionine
& p-hydroxyphenyl pyruvic acid
