Protein Flashcards
What 3 parts make up an amino acid
Acid group (carboxyl end) Amine group (amine end-nitrogen) Side Chain (20of these, some contain nitrogen)
What are the two conditionally essential amino acids?
Cysteine, Tyrosine
What do we mean conditionally essential
In order for us to make the conditionally essential amino acids we need enough of methionine (to make cysteine) and phenylalanine (to make tyrosine)
How many other amino acids can each amino acid bond to
TWO!
What’s the primary structure of proteins
sequence of amino acids
What’s the secondary structure of proteins
alpha helix, beta pleated sheet
What’s the tertiary structure of proteins
Interactions with itself
What’s the quaternary structure
The way one protein interacts with another
Does denaturation change protein sequence or amino acid content
NO. Denaturation only changes their unique conformations.
Does the mouth contribute to protein digestion?
No
How does the stomach contribute to protein digestion
The stomach acid denatures food proteins; it secretes protein digesting enzyme
How does the pancreas contribute to protein digestion
Secretes protein digesting enzymes
How does the small intestine contribute to protein digestion
It has enzymes that break dipeptides and tripeptides into single amino acids; Absorbs primarily single amino acids
What does the bloodstream do with protein digestion
Transports amino acids to all the body’s cell
What are the roles of protein in the body?
Enzymes, Hormones, Antibodies, Transport across cell membrane, Electrolyte and Fluid Balance, Acid-Base Balance, and Providing Energy.
Proteins transport
substances into and out of cells.
When will proteins provide energy?
- If the body is short on carbs and fat
- If you ate more protein than you need, it will convert it to carbohydrate and fat
- When the body has too much of any amino acid
- When the protein quality is poor
What’re the fates of an amino acid
- Build a protein
- Make a nitrogen containing molecule
- Make a different amino acid
- Provide energy in absence of sufficient carb
- Converted to ENERGY when protein in excess of need consumed
Which kinds of protein are the easiest to digest
Animal proteins: 90%
Legumes: 80%-90%
Grains and others: 70%-90%
Can the use of protein differ by circumstance?
YES. Depending on health, malnourished, infection, would healing.
What is the limiting amino acid?
The ESSENTIAL amino acid that is present in dietary protein in the lowest amount proportional to its requirement.
Portion size of animal protein
about 3 oz
Portion size of plant protein
Modest portion of any 3-4 foods
High protein diets are shown to have greater…
Weight loss
Appetite Suppression
Decrease in Blood Pressure
Decrease in Triglyceride
Satiety Rankings
Protein > Carbohydrate > Fat
Which population is in positive nitrogen balance?
Growing child, muscle builder, pregnant woman
Which population is in nitrogen equilibrium?
College student, healthy adult.
Which population is in negative nitrogen equilibrium?
Astronaut, surgery patient
Marasmus
Infants + toddlers, wasting, impaired growth, digestive tract deteriorates. Protein deficiency.
Kwashiorkor
1-3 year olds, swollen belly from fatty liver as a result of protein deficiency.
Are there potential adverse effects of too much protein?
Heart problems (or is it from saturated fat), Kidney (has to eliminate excess nitrogen), Bones (increased calcium excretion)
Do protein and amino acid supplements work?
Not really, also probably not safe.
What are the downside of single amino acids
They compete for carriers that are supposed to take up a range of amino acids; creates secondary deficiency of OTHER amino acids that aren’t sufficiently absorbed.
Does eating extra protein make your muscles grow larger
NO,
What is the RDA for protein for women?
46 g/day.
On average women get 65 g/day.
What is the RDA for protein for men?
58 g/day.
On average men get 105 g/day.
What’re the advantages of beans?
Soy protein quality and quantity is high, and they are excellent sources of fiber, B-vitamins, Iron, Calcium, Other Minerals.
Positive aspects of Vegetarian Diet
Protection from bad health consequences (obesity, diabetes, high bp); Difficult to separate contribution of replacement phenomena.
Positive aspects of Meat Eater’s Diet
Growth, Support during critical times, obtaining nutrients
Celiac Disease
An immune-mediated disease for which early serologic diagnosis and dietary treatment can prevent severe, sometimes life threatening complications.
Damages the lining of the small intestine and prevents proper nutrient absorption.
Gluten Intolerance
One of the most common genetic diseases of humankind, occurring in 1/130 to 1/300 individuals in the European general population.
Gluten
Composite of gliadin + glutenin.
Where is gluten located?
In the endosperm of wheat, barley, rye, and maybe oats.
Gluten Function
Seitan (fake meat), Bread dough elasticity, Chewy Texture
Gluten Free
A gluten-free diet is the only known effective medical treatment for celiac disease.
Can fat be converted into a different maconutritent?
NO
How much of the wheat kernel is gluten?
80%
How much of wheat flour is protein?
10%
Most individuals who go gluten free and “feel better” are likely to be experiencing?
A decrease in refined foods, which is still good for them.
What factors go into requirement standards for protein in terms of who the person is?
- Growing or not
- Body size
- Maintain/gain muscle mass
What types of diets are there when considering protein intake relative to requirement
Omnivore, Vegetarian, Vegan
What are protein requirements based on?
Muscle maintenance.
Vegan diets can be problematic in that they…
have poor amino acid distribution!
Someone on vegan diet will use less than their total consumption for functional purposes.
If you’re interested in gaining muscle mass, are you going to use MORE or LESS of your daily requirement?
MORE because you’re working on gains.
What is the limiting amino acid of grains (like white rice)
Lysine
What is the limiting amino acid of beans
Cysteine (or methionine)
What does PDCAA stand for
Protein Digestibility-Corrected Amino Acid score
What does the PDCAA score measure
- Amino Acid Distribution
- Digestibility (Fiber)
What foods will have better PDCAA score, Eggs or Soy?
EGGS (All animal foods have 100)
What is the DRI value for protein
.8/kg/day based on body weight.
Recommendation, not requirement.
What is the DV for protein
50 g/day
WHO recommendation for protein
10%-15% of daily calories
DRI AMDR for protein
10%-35% of daily calories
How much protein does the average person have stored for times of protein shortage
NONE; No storage depot
Do all plant foods contain all essential and non-essential amino acids?
YES.
When your body excretes protein…
It must remove the nitrogen group from the amino acid.
