Clinical Chemistry Exam 1 Lecture 3

Amino Acids are the building blocks of …
proteins and nonprotein nitrogen compounds
What do Amino Acids Regulate?
Growth
Repair
Maintenance of all cells
Structure of Amino Acid
Amino Group (NH2)
Carboxyl Group (COOH)
Side Chain (R)
Source of Amino Acids:
____ synthesized in sufficient quantities
____ “essential”
11
9
Where must the 9 essential AAs be supplied from?
Dietary proteins
Body Pool of Amino Acids
Diet
Newly synthesized
Those released from protein breakdown
Aminoacidopathies
Rare, inherited “inborn errors” of amino acid metabolism
Phenylketonuria (PKU)
Phenylalanine accumulates
What illnesses are associated with PKU?
Mental disabilities
Seizures
Behavioral Problems
What should you treat PKU with?
Restrictive Diet
What is the statistics with PKU?
1:10,000-15,000
What odor in the urine is associated with PKU?
Musty
Does Arkansas require PKU to be screen in newborns?
Yes
Tyrosinemia
3 types ranging in mild to severe
Temporary in some preemies
What is the statistics on Tyrosinemia?
1:100,000
What are the 5 illnesses associated with Tyrosinemia?
Failure to thrive, mental defects, vision problems, liver & kidney failure
Alkaptonuria
Homogentistic acid
Urine darkens upon exposure to air
What are the 4 illnesses associated with Alkaptonuria?
Arthritis
Heart Problems
Kidney stones in mid-30s
Skin pigmentation
What is the statistics on Alkaptonuria?
1:250,000
Maple Syrup Urine Disease
Sweet odor or urine and breath
What are the 3 substances associated with Maple Syrup Urine Disease?
Leucine
Isoleucine
Valine
What are the 4 illnesses associated with MSUD
Failure to thrive, seizures, coma, death
What is the statistics on MSUD?
1:185,000
What are the 3 illnesses associated with Homocystinuria
Nearsightedness
Abnormal blood clotting
Brittle Bones
What are the 2 less common illnesses associated with Homocystinuria?
Mental defects
Abnormal growth
What is the Statistics on Homocystinuria?
1:200,000
What is the statistics on Cystinuria?
1:10,000
What are the 3 illnesses associated with Cystinuria?
Defect in reabsorption/transport system
Kidney stones at a young age
Recurring UTIs
Albinism
4 types.
Lack of melanin in skin, hair, and eyes.
Photosensitivity and astigmatism.
What are people with Albinism at an increased risk for?
Melanoma
What is the statistic on Albinism?
1:20,000
Proteins are found in all ____, ____, ____, and _____
Cells
Fluids
Secretions
Excretions
What is the composition of proteins?
16% Nitrogen
Carbon
Oxygen
Hydrogen
Sulfur
Linked amino acids create what kind of bond?
Peptide
Most average 200-300 amino acids to form a ______ ______
polypeptide chain
Primary Structure of Proteins
The specific sequence of amino acids;
Secondary Structure of Proteins
Chains coil creating pleated sheets or helix
Tertiary Structure of Proteins
When helix folds to create 3 dimensional structure
Quaternary Structure of Proteins
When 2 or more polypeptide chains join to form a larger protein
What does the Primary structure of Proteins determine?
The function of the protein
What is an example of a Quaternary structure?
Hemoglobin
Conjugated Protein
Protein + Nonprotein group
Conjugated Protein:
Lipid + Protein =
Heme + Globin =
Lipoprotein
Hemoglobin
True or False:
Proteins are constantly synthesized and degraded
True
Metabolism/Catabolism of Proteins is often associated with which organs?
Liver
Lymph nodes
Spleen
Nitrogen Balance =
Intake/Synthesis – Degradation/excretion
Disintegration of proteins occurs where?
GI tract
Kidneys
Liver
Proteins break down to amino acids which can then be ___, ____, or _______ (____ ___ )
Recycled
Re-used
Re-purposed (Kreb’s Cycle)
The products of Amino Acids being broken down are?
Ammonia
Energy
CO2
H20
Liver converts ammonia into ______ which is excreted into urine
urea
All of the following are considered what?
Hormone receptors
pH buffers
Water balance
Osmotic pressure
Transporters of small molecules
Energy and nutritional source for tissues (12-20%)
Structural role (collagen)
Enzyme catalysts
Protective role (immunoglobulins)
Clotting factors
Muscle contractions
Functions of Proteins
What will cause decreased protein levels?
Burns, wounds, blood loss
Malnutrition or starvation
Liver disease
Renal disease
Malabsorption/GI Disease
What will cause increased protein levels?
Dehydration
Chronic inflammation or infection
Hemolysis (false +)
What 2 diseases are associated with increased protein levels?
MM & Waldenstrom’s
Denaturation
When the structure is disturbed, the protein’s function is lost
What causes Denaturation?
Heat
Repeated freeze-thaw cycles
pH extremes
UV light
Chemicals, detergents
What can cause a falsely elevated protein level?
Hemolysis
Where are most proteins synthesized?
Liver
Where are the immunoglobulins synthesized?
Lymph Nodes/Spleen