Lecture 8 Learning Goals

What is Biochemistry

The study of the chemistry of life.

What are the 4 biomacromolecules in our body?

NPCL( Nucleic acids, Proteins, Carbohydrates, Lipids)

Storage Proteins

Store Essential Substances for Immediate Availibility

Enzymes

Catalyst for biochemical reactions

Hormones

Messangers that regulate bodily functions

Transport Proteins

Carry substances through blood and cell membranes

Structural Proteins

Support and Mainntain the shape of cells

Protective Proteins

Provide defense against invaders ad protect from injury

Contractile Proteins

Do mechanical work

Why is it important to know protein structure?

• Structure dictates function

• Shape-determining interactions

• Hydrophobic Effect & Active Sites

• Structural Amino Acids

Isomer

compounds w same chemical formula, but diff structures

Constitutional Isomers

Isomers that differ in the bonding orders of atoms

Stereoisomers

Isomers that have atoms bonded in the same order, but diff arangements in space

what type of isomer is an enantiomer and what is one?

stereoisomer; mirror image

what type of isomer is an disastisomer and what is one?

stereoisoemr; and not a mirror image

how to classify an amino acid as nonpolar?

C-C and C-H bonds

how to classify an amino acid as nuetral polar?

mostly -OH, -SH, or -CONH2

How to classify an amino acid as Acidic?

-COOH/-COO-

How to classify an amino acid as basic?

LAH (lysisine, arganine, histine)

hydrophilic amino acid classifications

Nuetral polar, Acidic, Basic, Nonpolar

What are zwitterions?

Both positive and negative charges.(dipolar)

Under what conditions is an amino acid considered zwitterionic?

At PH 7.

Which amino acids have negatively charged side chains?

(-) charged side chains. (the acidic duo)

aspartate & glutamate

What happens at PH 7 ?

they give away a hydrogen ion to surrounding water, leaving them w a carboxylate ion

What side chains are positively charged?

LAH( Lysine, Arganine, Hysine)

What are zwittterions?

have both positive and negative charges.

What is the primary structure of a protein and what conventions are used to draw and name the primary structures?

2 amino acids covalently linked together by a peptide bond form a dipeptide

How are protein structures written?

N terminus——> C terminus

Glycine

Flexible one; has the smallest side chain possible— can squeeze into tight spaces easily and forms into a protein

Proline

The rigid stiff one; makes a ring so it cannot bend freely.

Cystein

The glue; when 2 cisteins get close together, the -SH groups react and form a strong covalent disulfide bond

One of the structures for secondary structures within a protein

Alpha helix; right handed spiral structure

Other structure for secondary structure within a protein

Beta Sheet; Sheet structure made up of indivusual beta strands

Shape determining interactions in a protein strycture

Covalent bonds (peptide bonds and disulfide bonds) and Noncovalent interactions(salt bridges, h-bonds, van der waals, hydrophobic effect)

primary structures

linear sequence of amino acids

secondary structure

local folding patterns

tertiary structure

one single polypeptide chain

quaternary structure

multiple polypeptide chains

which side chains are hydrophilic?

polar, acidic, and basic

which side chains are hydrophobic

nonpolar