Proteins Flashcards
Protein was derived from which greek word?
Proteios
“of first importance”
Protein purposes
Polymers of amino acids
Provide structure in membranes
Build cartilage and connective tissue
Transport oxygen in blood and muscle
Direct biological reactions as enzymes
Defend the body against infection
Control metabolic processes as hormones
A source of energy
What elements does proteins provide organisms? (7)
Carbon
Hydrogen
Nitrogen (unavailable from fats and carbs)
Oxygen
Sulfur (unavailable from fats and carbs)
Some specialized proteins have Iron and Phosphorous
Protein main intro (3)
A naturally occuring, unbranched polymer in which monomer units are amino acids
A peptide in which at least 40 amino acid residues are present
Most abundant molecules in the cells after water - 15% a cell’s overall mass
Contains one polypeptide chain
Contains 2 or more popypeptide chains
Monomeric
Multimeric
Types of protein based on CHEMICAL COMPOSITION
Simple protein - only amino acid residues are present
Conjugated (complex) protein - one or more non-amino acid entities
Types of protein based on SHAPE
Fibrous proteins (insoluble): Alpha-Keratin & Collagen - arranged in long strands
Globular Proteins (soluble): Myoglobin & Hemoglobin - arranged into spherical or globular shapes
Types of proteins based on FUNCTION
Catalytic proteins - catalyst for chemical reaction
Defense proteins -immunoglobulins/antibodies
Transport proteins - Bind small biomolecules AND transport them
Messenger proteins - transmit signals
Contractile proteins - Necessary for all movement
Structural proteins - stiffness and rigidity
Transmembrane proteins - Help control movement of small molecules
Storage proteins - Bind small molecules
Regulatory proteins - embedded in the exterior as receptors
Nutrient proteins: important in the early stages of life
Simple proteins (4) only amino acids are present
Albuminoids - keratin
Albumins - egg album, serum albumin
Globulins - antibodies
Histones - chromatin in chromosomes
Conjugated [complex] proteins and their prosthetic (6)
Hemoproteins (heme) - binds oxygen to blood
Lipoproteins (lipid) - lipid carrier
Glycoproteins (carbohydrate) - antibody, lubricant
phosphoproteins (phosphate) - enzyme in glycogen
nucleoproteins (nucleic acid) - protein synthesis
metalloproteins (metal ion) - storage complex for iron
Globular proteins are known to be folded into spherical or globular shapes
What is their interior and exterior?
Nonpolar amino acid in interior
Polar amino acid in the surface
Fibrous proteins (insoluble) 5
Keratin - wool, fingernails
Collagen - tendons, bone, connective tissue
Elastins - blood vessels and ligaments
Myosins - muscle tissue
Fibrin - blood clots
Globular proteins (soluble) 5
Insulin - regulatory hormone for glucose
Myoglobin - oxygen storage
Hemoglobin - oxygen transport in blood
Transferrin - Iron transport
Immunoglobulin - Immune system responses
Where does the functional versatility of proteins stem from?
Bind small molecules specifically and strongly
Bind other proteins and form fiber-like structures
Ability integrated into cell membranes
Structural proteins:
Component of cartilage
Gives mechanical strength and protective covering
Collagen
Keratin
