3S: Proteins
description
Transcript of 3S: Proteins
3S: Proteins
Shireen Rudina
What do proteins do?
• Structure– Collagen in skin, keratin in hair and nails
• Signaling between cells
• Defend against disease– Antibodies
• Facilitate Reactions (enzymes)
• Do essential work in each cell
Which of these are proteins:
1. DNA2. Fibers in your heart muscle3. ?4. ?
Catalase is an enzyme
2H2O2 2H2O + O2 + heat
Does not happen spontaneously, only in the presence of catalase.
Important: Keeping your data organized!
Bubbles Heat Splint Test
Control
Liver
Liver, high pH
Liver, low pH
Heated Liver
Peptide Bonds Connect Amino Acids
Proteins are made of monomers called amino acids
Polypeptide
• Many amino acids connected by peptide bonds polypeptides
20 amino acids
Structural Activity
Primary Structure
• Order of amino acids linked together in a long chain
• One end carboxyl & one end amino
Secondary Structure
• Chain of a.a.s bends based on the R groups
Alpha helix or Beta pleated sheets
Tertiary Structure
• Further folding of the polypeptide chain– Disulfide bridges
Quaternary Structure
• Different polypeptide chains come together to form the final protein