proteins

denaturation

a process in which a protein unravels and loses its native conformation, thereby becoming biologically inactive. In DNA, the separation of the two strands of the double helix

celiac disease

autoimmune disorder cause poor absorption of nutrients in small intestine Inflames or destroys villi 1 in 3 Americans Cannot tolerate gluten, the protein in wheat, barley, and other grains

protein make up

carbon, hydrogen, oxygen, nitrogen

deamination

removing the nitrogen-containing group from an unneeded amino acid; once the nitrogen is removed, the remaining amino acid is a carbon skeleton (occurs primarily in the liver)

protein functions

structural support, storage, transport, enzyme catalysis, cellular communications, movement, and defense against foreign substances

nutrigenomics

study of how food impacts health through its interaction with our genes and its subsequent effect on gene expression

nutrigenetics

study of the effects of genes on nutritional health, such as variations in nutrient requirements and responsiveness to dietary modifications

nitrogen balance

the amount of nitrogen consumed as compared with the amount of nitrogen excreted in a given period of time

amino acids

a simple organic compound containing both a carboxyl (—COOH) and an amino (—NH2) group that build proteins

RDA for protein

0.8 g/kg of body weight

AMDR for protein

10-35% of total calories

ammonia (NH3)

A compound of nitrogen and hydrogen. This is the result of Nitrogen gas (N2) once it is "fixed." converted to urea and excreted in the urine

hemoglobin functions

Carries oxygen from lungs to peripheral tissues At tissues with low oxygen (peripheral capillaries) Hemoglobin releases oxygen Binds (picks up) carbon dioxide and carries it to lungs When bound to CO2, hemoglobin becomes carbaminohemoglobin

acidification

increase in the concentration of acid

absorptive cells

Intestinal cells that line the villi; and participate in nutrient absorption (after protein digestion, most amino acids are transported here)

vitamin B12 sources

Milk, beef, poultry, shellfish, eggs

Vitamin E sources

Vegetable oils, whole grains, green vegetables, almonds

potassium sources

all whole foods; meats, milks, fruits, vegetables, grains, legumes

dispensable (nonessential) amino acids

amino acid is one that can be synthesized by a healthy body in sufficient amounts (there are 11)

di/tripeptides

co-transported with H+ broken down to amino acids in microvilli

protein complementation

combining incomplete protein sources to provide all of the essential amino acids in relatively adequate amounts

hemoglobin structure

complex quaternary structure; four globular protein subunits- each with one molecule of heme (each heme contains one iron ion)

deoxyribonucleic acid (DNA)

contains the codes for making proteins

high-protein diet

defined as more than 35% of total caloric intake from protein

protein quality

depends on its amino acid composition and its digestibility; high-quality have high-bioavailability

ATP synthase

enzyme that catalyzes the reaction that adds a high-energy phosphate group to ADP to form ATP

celiac disease symptoms

gas diarrhea stomach pain fatigue joint pain weight loss itchy skin

protein alterations

heat, physical agitation, acids can cause fragments in polypeptide chains that can lead to loss and protein misfolding

nitrogen is eliminated through

intestinal tract sheds cells urinary elimination loss of hair and nails

hemoglobin

iron-containing protein in red blood cells that carries oxygen for delivery to cells

r group

is any group in which the carbon or hydrogen is attached to the rest of the molecule; a functional group that defines a particular amino acid and gives it special properties

high-protein diet disadvantages

kidney stress cardio disease risk cancer risk osteoporosis risk

folate sources

leafy green vegetables, legumes, seeds, enriched grains, orange juice

protein structure

long chains of amino acids; impacts it's function

amino acid derivatives

nitrogen-containing compounds that are not proteins but have important physiological roles (creatine, melanin)

protein

organic compound that is made of one or more chains of amino acids and that is a principal component of all cells

protein turnover

process of continuous breakdown and synthesis of protein from its amino acids and recycles them to make new proteins

transamination

process of transferring a nitrogen-containing group to another substance to make an amino acid (reactions are reversible)

microvilli

projections that increase the cell's surface area for absorption; enzymes within the microvilli break down

complete proteins

proteins containing all 9 essential amino acids; found only in soy and animal foods (meats and dairy products)

incomplete proteins

proteins that are missing one or more of the essential amino acids; found in plant sources (nuts and legumes)

edema

puffy swelling of tissue from the accumulation of fluid

eggs

rates high in protein quality because it is well digested and has a pattern of essential amino acids that closely resembles that used by humans

complementary protein dishes

red beans and rice peanut butter on bagel hummus with sesame seeds black beans cornmeal tortilla

vegetarianism

the practice of eating a diet consisting entirely or largely of plant foods

hydrogenation

the process of adding hydrogen to unsaturated fatty acids to make fat more solid and resistant to the chemical change of oxidation

Bioenergetics

the study of how energy flows through living organisms

high-protein diet advantages

weight loss blood sugar regulation reduced LDL cholesterol reduced blood triglycerides reduced blood pressure bone health

essential amino acids

amino acids that are needed, but cannot be made by the body; they must be eaten in foods (there are 9: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine)