Chapter 6-Proteins Flashcards
Proteins contain what atoms? Which one is different from carbs and fats?
- carbon
- hydrogen
- oxygen
- Nitrogen (this one is unique to proteins)
What does amine mean?
Containing nitrogen
What are the components of an amino acid?
- Carbon
- Hydrogen
- Amino group
- Acid group
- Side group/chain
What part of an amino acid varies in amino acids?
The side group
What are nonessential amino acids and how many are there?
- Our body can make these if we have the right building blocks.
- 11 nonessential AAs
What are essential amino acids and how many are there?
-We must ingest them because we cannot make in enough quantity
-9 essential AAs
How are amino acids bonded together and what kind of reaction does that?
-Amino acids are linked together with a peptide bond.
-The reaction to make that peptide bond between amino acids is a condensation (makes water) reaction.
Primary structure of a protein
- long chain of amino acids linked together by peptide bonds
-It is determined by the order of amino acids - not working protein
Secondary structure of protein
- refers to the coiling or folding of a polypetide chain that make helices or sheets
-it’s coily because it’s determined by the electrical attractions between hydrogen and oxygen. Some like each other and some don’t.
-not a working protein
Tertiary structure of a protein
-3D folding pattern of a protein due to side chain interactions
-the unique side groups can be hydrophilic or hydrophobic
- working protein!
-Most proteins stop here
Quaternary structure of a protein. What is one example?
-protein consisting of two or more polypeptides (more than one AA chain)
-hemoglobin
Protein denaturation
-clips the bonds that holds protein together
-very important so we can digest protein
How can you remember the order of transcription and translation?
C comes before L
TransCription comes before transLation
Where does transcription and translation occur?
Transcription in nucleus
Translation at ribosomes
Process of Protein Synthesis (Transcription and translation)
- mRNA in the nucleus unwinds DNA and transcribes (takes an exact replica of DNA)
- mRNA travels to the ribosome to translate the message into the language of proteins
- tRNA comes to the mRNA and mRNA tells them which AAs to put and in what order
Gene expression
- the process by which a cell converts the genetic code into RNA and protein
-the process of making a protein
What protein is found in the largest amount in our bodies?
Collagen
Proteins as enzymes: 5 major functions
- Break down substances, build up substances (bone) and transform substances (AA to glucose)
- Catalysts
What are two examples of hormones that start as proteins?
Insulin and glucagon
How do proteins regulate fluid balance?
-protein attracts water to a cell, so you place proteins where you want water to be
How do proteins act as acid-base regulators?
Proteins can attract or release hydrogens to balance pH. They act as a buffer
8 roles/functions of proteins
- Structural materials
- Enzymes
- Hormones
- Fluid balance regulators
- Acid-base regulators
- Transporters
- Antibodies
- Source of energy and glucose
Where do the AA in the AA pool come from?
- AA from dietary proteins
- AA from protein breakdown
What are 5 things made from AA leaving the AA pool?
- More proteins (protein synthesis)
- Energy production
- Glucose production (gluconeogensis)
- Make fat
- Make other non-proteins molecules that contain nitrogen
Nitrogen balance
the balance between protein synthesized and protein degraded
Positive nitrogen balance
-when the amount of protein synthesized is more than the amount of nitrogen excreted.
- happens in pregnant women, growing children
Negative nitrogen balance
-when the amount of nitrogen excreted is more than what’s synthesized
-happens in the elderly and sick
Zero nitrogen balance
-the amount of nitrogen that you’re making to keep on the body is the same that you’re degrading/excreting out
-most healthy, non-growing adults
What does the body do if essential amino acids are missing from the amino acid pool?
- Break down lean tissue
- Skip making that protein
What does the body do if a nonessential amino acid is missing?
- Make it
- Transaminate (move nitrogen group from one AA to make another)
What has to happen to use protein for energy?
You have to deaminate the amino acid because it can’t go through the energy cycle with Nitrogen.
3 main points about urea
- Principle vehicle for excreting unused nitrogen
- Increases with protein intake
- Requires water to dilute and excrete urea
The process to make urea
- Amine group is broken off of AA to make ammonia
- Ammonia quickly turns to urea (safer to be excreted out)
The quality of protein is determined by
- Digestibility
- Amino acid composition
Digestibility of:
1. Animal proteins
2. Legumes
3. Other plants
- Animal 90-99%
- Legumes 90%
- Other plants 70-90%
What are the two quality types of protein with examples?
- High quality/complete- animal foods, soy, and maybe quinoa
- Low quality/incomplete-other plant foods
Best complimentary protein mix
Legume (peanut butter) and grain (bread)
5 health effects of protein
- Protein deficiency
- Heart disease (debate over saturated fat from animal protein)
- Adult bone loss (used to think this but not not true)
- Weight control
- Kidney disease
AMDR (acceptable macronutrient) of protein
10-35%
RDA (recommended dietary allowance) of protein. Know this for calculations!
0.8g/kg
How many grams of high quality protein can be useful for muscles, alertness, and fulness
25-35 grams
Protein equivalents to 7 grams protein:
- ____ oz cooked meat/fish/poultry
- ___egg
- __ cup cooked beans/peas/lentils
- ___ oz nuts/seeds
- __ oz tofu
- ___ TB peanut butter
- 1 oz cooked meat/fish/poultry
- 1 egg
- 1/4 cup cooked beans/peas/lentils
- 1/2 oz nuts/seeds
- 2 oz tofu
- 1 (really 2) TB peanut butter
How many protein equivalents is one cup of milk products?
How many grams of protein in one serving of vegetables and grain?
8 grams
2-3 grams
Epigenome
chemical tags that can tell the genome what to do (stay on or off).
They don’t change the sequence of DNA
Nutrigenetics
your actual genetic makeup determines aspects of nutrients such as how much you absorb or need
Nutrigenomics
what is in your diet can affect the activities of genes - often that is through changes to the epigenome
