α-helix and β-pleated sheets, structure held together by hydrogen, disulfide and covalent bonds formed between the different R groups

folds into a compact a three-dimensional structure.

The arrangement of 2 or more polypeptide chains together. 

Which are cause of Denaturation?

Proteins made only of amino acids

Can be further classified as globular or fibrous

proteins combined with non amino acid groups

symmetric and water soluble

ex. Albumin, globulins, histones, protamines

asymmetric and water insoluble

ex. Collagens, elastin and keratin

DNA or RNA nucleic acids

large carbohydrates attached

smaller carbohydrates

cholesterol, triglyceride, or phospholipids

metal (ex. Cu or Fe)

phosphate groups

Catalyse chemical reactions

Transminases, phosphatases, dehydrogenases

Chemical messengers that control the actions of specific cells or organs

Insulin, growth hormone, cortisol

special ions, small molecules or macromolecules across biological membranes

Hemoglobin, albumin, transferrin

Mediate humoral immune response to aid and neutralize foreign objects

IgG, IgM, IgA

Structures of cells and tissues

Collagen, elastin, keratin

Serve as reserves of metal ions and amino acids

ferritin

Reserve source of energy

Maintain water distribution between cells and tissue, interstitial compartments and the vasculature

albumin

Most prominent band on the electropherogram

Smallest molecular weight and fastest moving fraction

Amounts of 50-65% of the total protein (3.5-5.2 g/dL)

FUNCTIONS:

Regulates osmotic pressure and fluid balance

Serves as a transport molecule for many cations and non-water soluble substances (Ca++, fatty acids, bilirubin, etc.)

α1, α2’ β and gamma (ϒ) fractions

Total- albumin

Now known as Transthyretin

migrates slightly ahead of the albumin band on electrophoresis. It is not part of the total protein family. It is not a precursor to albumin

Crosses the blood-brain barrier and has a distinct band on CSF electrophoresis

transports thyroxine (T4), triiodothyronine (T3)

Combines with retinol-binding protein to transport retinol (biologically active form of vitamin A)

indicator of nutritional status; decreased levels are seen in malnutrition

Increased levels in steroid therapy, chronic renal failure and alcoholism

measures ALL of the proteins in plasma

Measurements reflect

Nutritional status

Kidney disease

Liver disease

Other