Week 4 - "Proteins"

Proteins

Naturally occurring and branch of monomer unit; amino acids; they account for 15% of all a cell's overall mass

Proteins

Responsible for moving substances such as nutrients and electrolytes across the membrane; hormones and neurotransmitter

Proteins

Ack as markers; process by which different cells recognize each other

9000

________ different kinds of proteins in a typical human cell

100,000

Number of different proteins found within the human body

Proteins

Needed for the synthesize of enzymes, certain hormones and some blood component; maintenance, repair of existing tissues and synthesis of new one

Carbon, Hydrogen, Oxygen and nitrogen

All proteins contain the elements _____________ (4) almost all contain sulfur

15.4%

The average nitrogen proteins is _______ by mass

Amino acids

Contain both amino and carboxyl groups attached to the same carbon atom; building blocks for proteins

R-Groups

Non polar amino acids are _______

Polar Neutral

Contains polar but neutral side chains; 7 amino acids

Polar Acidic

Contains carboxyl as a part of side chains; 2 amino acids

Polar Basic

Contains amino group as part of the side chains; 2 amino acids

Casein

Main protein of milk (phosphorus); important diet of infants and children

Hemoglobin

Oxygen transporting protein of blood; Iron

Alanine, Cystein, Glycine

Non Polar examples (first 3 lang nandito pero madami yun)

Arginine, Asparagine, Aspartic Acid

Polar examples (first 3 lang nandito pero madami yun)

Polar Amino Acid

Oppositely charged; electron is not evenly distributed in the molecule can cause a "dipole mole"

Dipole mole

One end of the molecule is positive while the other is negative

Non-polar

Equally charged amino acid

Cystein

Unique sulfhydryl group; Non essential amino acid. Nails, skin and hair and for collagen making

Peptide

Short chain amino acid; it build muscle, boost weight and muscle recovery

Peptide Bond

Covalently bonded between amino acids

Dipeptide Bond

Covalently bonded between 2 amino acids

Oligopeptide

Covalently bonded between 10-20 amino acids

Polypeptide

Covalently bonded between many amino acids

Isomeric Peptides

Same amino acid but different order and are of different molecules with different property

Hormonal action, neurotransmission, antioxidant activity

Biochemically important peptides

Oxytocin and Vasopressin

Best known peptide hormone; made by pituitary glands

Vasopressin

Lactation, water balance, and skeletal integral

Oxytocin

Uterine contraction, breast tissue for lactation after birth.

Enkephalin

Small peptide neurotransmitter

Met-Enkephalin, Leu enkephalin

Help reduces pain; produced by the brain and bind receptors

Glutathione

Small Antioxidant; known for whitening but also serve as regulation of oxidation, protects cellular component from oxidation of peroxide and superoxide

Simple protein

Amino acid residue is present

Conjugated protein

One or more amino acid residue are present

Lipoprotein

Lipids prosthetic groups

Glycoprotein

Carbohydrate groups

Metalloprotein

Specific metal as prosthetic groups

>10,000

Count of Amino acid residue known

400-500

Common proteins contain ______ to _______ amino acid residue

40-100

Small proteins contain _____ to ____ amino acid residue

Monomeric

Contains one peptide chain

Multimeric

Contains more than one peptide chain

Primary structure

Order in which amino acids are linked together in a protein

Frederick Sanger (1953)

First to sequence and determine the primary structure for the first protein; Insulin

Secondary Structure

Arrangement of atoms of backbone in space; Alpha-helix and beta-pleated

Alpha-Helix

Adopts the coil like spring shape

Beta-pleated sheets

Completely extended amino acid chains

Tertiary Structure

Three-dimensional shape

Quaternary Structure

organization among the various peptide chains in a multimeric proteins

Fibrous, globular, membrane

Three types of proteins

Fibrous proteins

elongated shaped; generally insoluble in water, linear structure; hair, nails

Globular proteins

Folded into spherical shapes; generally soluble in water; functions as enzymes and intracellular in the protein core

Membrane proteins

Associated with cell membrane; Insoluble in water; helps in transport of molecules the membrane

Alpha-Keratin

Protective coating for organs; protein constituent of hairs, feather and nails

Collagen

30% Most abundant protein; structural material in tendons, ligaments and blood. Rich in proline 20%

Myoglobin

Oxygen storage molecules in muscles; serve as reservoir of oxygen source for working muscles

Hemoglobin

Oxygen carrier molecule in blood; transport oxygen from lungs to tissues. Can transmit up to 4 oxygen molecules

glycoprotein

a conjugated protein having a carbohydrate component

Junction

Serve to connect and join cells together

Enzyme

Fixing membranes; localizing metabolic pathways

Transport

Helps facilitated and active transport

Recognition

Marker for cellular identification

Immunoglobulin

Protective response to the invasion of microorganism or foreign molecules

Lipoproteins

Help suspend lipids and transport them into the bloodstream

Chylomicrons

Transport dietary triacylglycerol's from intestine and liver to adipose tissue

Very-low density lipoproteins

Transport triacylglycerol synthesized in the liver to adipose tissues

Low-density lipoproteins

Transport cholesterol synthesized in the liver to cells throughout the body

High-density lipoproteins

Collects excess cholesterol from the body tissue and transport it back to the liver for degradation to bile acids