PROTEIN DENATURATION

trichinosis

( a parasitic disease caused by roundworms).

histones

- hydrolysis products of nucleoproteins - small MW proteins which are basic - soluble in acid solutions - usually form complex with nucleic acid

collagen

makes up tendons and developing bones, cartilage

Keratin

mechanical strength as well as protective covering to hair, fingernails, feathers, and hooves

Actin

moving filaments in myofibril

globulin

one of the 3 types of serum proteins; insoluble in salt free water, soluble in dilute salt solution but when concentration of salt brought to 30-50 percent saturation they are insoluble.

ultraviolet radiation

operates very similarly to the action of heat (e.g. sunburning)

Fibrinogen

precursor of fibrin in blood clotting

Derived Proteins

products of hydrolysis of simple and conjugated proteins; coagulated proteins that are formed by heating or treatment of alcohol, acids and bases; hydrolysis products and modification products of other classes proteins

secondary derived proteins

progressive hydrolytic product of protein hydrolysis. e.g., proteoses, peptones, polypeptides and peptides

active and passive proteins

protein classification according to activities (2)

simple, conjugated, derived proteins

protein classification according to chemical differences (3)

fibrous and globular

protein classification according to shape (2)

True

pure isopropyl or ethyl alcohol is less effective than the commonly used 70% alcohol solution. true or false

reducing agents

reduces disulfide linkages to produce -SH groups

insulin and glucagon

regulates or controls carbohydrate metabolism

metaprotein

second stage of protein hydrolysis obtained by treatment with slightly stronger acids and alkalies

zein

seed protein of corn

gliadin

seed protein of wheat

conjugated proteins

simple proteins linked to non-protein groups (prosthetic groups)

Myosin

stationary filaments in myofibril

fibrous

structural proteins of animals and include the proteins of hair, skin, nails and connective tissues; arranged in parallel along a single axis; insoluble in water and generally resistant to denaturation e.g. collagen, keratin, myosin and fibrin

lactic acid

the curdling of milk that takes place when milk sours or cheese is made results from the presence of ---, a by-product of bacterial growth.

According to Biological Importance

1. body's main destiny source of nitrogen and sulfur 2. catalytic and structural functions 3. they make up contractile system of muscles 4. as antibodies, they are the defense system of the body 5. as hormones, they regulate the body's glandular activity 6. in the blood, they maintain the fluid balance as part of clotting process and transport oxygen and lipids 7. they can act as poisons, such as venous in animal bites and stings or toxins, such as the bacterial toxin that produces botulism in humans from eating improperly processed foods 1. some antibodies that are secretions of bacteria and fungi

salts of heavy metals

8.) metal ions combine with -SH groups and form poisonous salts

hydrochloric acid

A curdy precipitate of casein, the principal protein in milk, is formed in the stomach when the --- of gastric juice denatures the casein; denature protein involves in hydrolysis of protein

true

Because the biochemical function of a protein depends on its three-dimensional shape, the result of denaturation is loss of biochemical activity. true or false

true

For limited denaturation changes, it is possible to find conditions under which the effects of denaturation can be reversed; true or false

IgE

Form if you have allergies; cold weather

Ovalbumin

Found in egg white

heat

In surgery, --- is often used to seal small blood vessels.

cauterization

In surgery, heat is often used to seal small blood vessels. This process, which involves denaturation, is called

dry heat sterilization

It is the process of killing bacterial spores and microorganisms using a high temperature.

primary structure

Protein denaturation does not affect the --- of protein.

true

Pure alcohol quickly denatures and coagulates the bacterial surface, thereby forming an effective barrier to further penetration by the alcohol. true or false

ionizing radiation

The effect of ultraviolet radiation from the sun, an --- , is similar to that of heat. Denatured skin proteins cause most of the problems associated with sunburn.

coagulation

The precipitation out of biochemical solution of denatured protein is called .

Defense proteins

These proteins are called immunoglobulins or antibodies, are central to the functioning of the body's immune system. They bind to foreign substances, such as bacteria and viruses, to help combat invasion of the body by foreign particles. Cont. (Protective/Defense proteins). ex. fibrinogen and thrombin

contractile proteins

These proteins are necessary for all forms of movement.; structural components of muscles, for control and relaxation. e.g., Actin and myosin

Nutrient/Storage Protein

These proteins are particularly important in the early stages of life, from embryo to infant. Casein, Ovalbumin, zein and gliadin

Transport proteins

These proteins bind to particular small biomolecules and transport them to other locations in the body and then release the small molecules as needed at the destination location. e.g., hemoglobin, transferrin, and HDL & LDL

structural proteins

These proteins confer stiffness and rigidity to an otherwise fluid-like biochemical systems. e.g. α-Keratin, Collagen, and elastin

Messenger proteins (Hormones)

These proteins transmit signals to coordinate biochemical processes between different cells, tissues, and organs.; not all hormones are protein in nature e.g. Insulin & Glucagon and human growth hormone

histones

act as spool

detergent

affects R-group interactions

serum albumin

albumin in blood

Alcohols

are an important type of denaturing agent

globular

arranged in tight, compact spherical shape; soluble in water; they are proteins of meat, milk, and eggs; more sensitive to denaturation than fibrous proteins

simple proteins

basically composed of amino acids e.g. egg albumin, serum albumin, lactalbumin (whey protein)

Catalytic proteins (Enzymes)-

biggest class of proteins; enzymes participate in all metabolic reactions in cells; biological catalyst

Sperm

can "swim" because of long flagella made up of contractile proteins

HDL & LDL

carriers of cholesterol in the bloodstream

Transferrin

carries iron from the liver to the bone marrow

Hemoglobin

carries oxygen from the lungs to other organs and tissues.

violent whipping or shaking

causes molecules in globular shapes to extend to longer lengths, which is then entangle.

microwave radiation

causes violent vibrations of molecules that disrupt hydrogen bonds

1. structural proteins 2. contractile proteins 3. catalytic proteins (enzymes) 4. messenger proteins (hormones) 5. transport proteins 6. defense proteins 7. nutrient/storage proteins 8. Toxins

classification of proteins by biological functions

Thrombin

component of clotting mechanism

Albumin

constitute the most important group of simple proteins, water-soluble; may be precipitated from solutions of high salt concentration, they are coagulated by heat.

coagulated proteins

denatured protein produced by agents such as heat, acids, alkalies

primary derived proteins

denatures or coagulates or first hydrolyzed product of proteins.

Strong acids and bases

disrupts hydrogen bonds and salt bridges; prolonged action leads to actual hydrolysis of peptide bonds

heat

disrupts hydrogen bonds by making molecules vibrate too violently; produce coagulation, as in the frying of an egg

passive proteins

do not have the ability to bind with other molecules to perform their functions

messenger proteins (hormones)

e.g. Insulin & Glucagon and human growth hormone

globulin

e.g. globulin of blood serum, egg white, fibrinogen of blood

proteans

earliest product of protein hydrolysis obtained by treatment with slightly stronger acids and alkalies.

elastin

elastic connective tissues

irreversible

for extensive denaturation changes, the process is usually .

Casein

found in milk

IgA

found in the respiratory tract

Collagen

from fish skin

Active Proteins

have the ability to bind with other molecules These proteins have receptors that bind to specific molecules (e.g., glucose) and transport them across the cell membrane.

Sperm

human reproduction depends on the movement of ---

IgG

in the blood and other fluids

albuminoids

insoluble in water and all neutral solvents; are not coagulated by heat e.g. keratin of hair, collagen of the bone and cartilage elastin of the yellow elastic fibers of the connective tissues.

organic solvents

interferes with R-group interactions because these solvents also can form hydrogen bonds

Loss of water solubility

is a frequent physical consequence of protein denaturation

heat-induced denaturation

is also used in sterilizing surgical instruments and in canning foods; bacteria are destroyed when the heat denatures their protein.

protein denaturation

is the partial or complete disorganization of a protein's characteristic three dimensional shape as a result of disruption of its secondary , tertiary, and quaternary structural interactions.

renaturation

this restoration process, in which the protein is "refolded" is called

ricin

toxic protein of cottonseed

toxins

usually produced by bacteria or plants

Lactalbumin

whey protein

Enzymes

which function as catalysts for almost all body reactions, are protein. Inactivation of enzymes through denaturation can have lethal effects on body chemistry.