Lecture 1: Intro

Question 1

Building Blocks of Life

Answer 1

• Proteins are polymers of amino acids linked by peptide bonds
• DNA are polymers of nucleotides linked by phosphodiester bonds
• Bonds are formed/broken by enzymes

Question 2

Types of Proteins

Answer 2

• Enymes
• Transporters
• Lipoproteins
• Hormones
• Signaling molecules
• Receptors
• Recognition molecules
• Glycoproteins
• Structural proteins
• Motility proteins

Question 3

Structure is key

Answer 3

• Structure of a protein is important for function
• Cellular diseases may arise when genetic mutations affect structure/function of protein

Question 4

Proteins contain different kind of bonds

Answer 4

• Covalent bonds hold together amino acids
• Non-covalent allow chains to fold into structure
• Cofactors may be bound covalently or non-covalently
• Transporters may also bind non-covalently
• Chemical functional groups mediate binding

Question 5

Cofactors

Answer 5

• Many proteins contain non-protein molecules that assist with structure/function
• Prosthetic groups are larger chemicals that are tightly bound by covalent/non-covalent forces
• Coenzyme is a type of cofactor that suttles commonly used functional groups

Question 6

Different types of interactions

Answer 6

• Covalent bonds
• Ionic interactions
• Hydrogen bonds
• Hydrophobic interactions
• Van der Waals

Question 7

Hydrogen bonds

Answer 7

• Strong attractive non-covalent forces
• Hydrogen atoms are covalently bonded to electronegative elements(O, N, S)
• Electronegative atoms have lone pairs of electrons that act as hydrogen bond acceptors
• Can occur between molecules or within parts of a single molecule

Question 8

Importance of water

Answer 8

• Water can form up to 4 transient H-bonds
• Important for molecule solubilization and formation of complex structures

Question 9

Hydrophobic effect

Answer 9

• Nonpolar molecules aggregate in an aqueous solution, excluding water molecules
• Main driving force behind formation of macromolecular structure
• Exclusion of water leads to increase in entropy of water molecules, obeying second law of thermodynamics
• Macromolecules fold to exclude water, preventing reactions while maximizing interactions of hydrophilic functional groups with water for solubility