Biochemical Unity of Life

Mass difference is 100,000,000 X but at a molecular level remarkable similar.

In what ways are bacteria, plants, & elephants biochemically similar?

Elements of Life and their AvailabilityMiss selection for carbon and silicon?

Consider:

[1] Bond strength in catabolism/ anabolism

[2] Combustion products

Biochemical Functional Groups

Biochemical Functional Groups

I. Proteins – Catalysis, Structure and energy

Biomolecules: Four Major Classes

Directional convention:

Amino Acid Chemical Structure Representations

Name the structure and color types?

Why have these different representations?

Biochemical Polymers

• Finite common monomer motif generates a huge polymer variety

• Specific residue linkage

• Polymer directionality

Synthetic or natural monomer/polymer pairs?

Biochemical Polymers

Dehydration Synthesis

Peptide bond

H2O +

Dipeptide

The Protein Cytoskeleton Provides Cell Shape and Movement

Are also proteins shown that are involved in catalysis?

Human Endothelin: Polypeptide Structure

A signaling protein that constrict blood vessels and raise blood pressure

Twenty one amino acid residues

Shaded blue tored (N→C)

Biomolecules: Four Major Classes

II. Nucleotides – Information catalysis and structure

RiboseTriphosphate Adenine

Adenosine Triphosphate: building block/energy storage

What is the difference between a nucleotide, a nucleoside, and a nucleic acid?

Nucleotides: Sugars and Bases

Compare and Contrast:

Deoxyribonucleic acid (DNA)

versus Ribonucleic Acid (RNA)

Biochemical Polymers

+

Dehydration Synthesis

+ H2O

Phosphodiesterbond

Nucleic Acid Sequence: Structural Representations

CGUACG

How can you ascertain if this is an RNA or DNA sequence?

What is the color coding in this structure?

Biomolecules: Four Major Classes

III. Lipids – Energy Storage and Barrier

Common structural features for lipids?

Biomolecules: Four Major Classes

IV. Carbohydrates – Fuel, Structure and Information

How many chiral centers in glucose?

In what form do humans store sugars?

Biochemical Polymers

+Dehydration Synthesis

+ H2OGlycosidic bond

Humans are excellent at distinguishing metabolite stereochemistry

Glucose and its Polymers Starch and Cellulose

Match terms with cellulose or starch:

Edible/Inedible; Helical/Linear; Alpha/Beta-Linked

Biological Functions for Biopolymers

What is an example of polysaccharides encoding for information?

Carbon Oxidation and Reduction: Life’s Energy Exchange

Where would sugars, lipids, gasoline, carbon dioxide and methane gas be placed on an poor/rich energy scale?

Carbon Oxidation Ranking from Most Oxidized to Most Reduced

How does acetyl-aldehyde versus ethanol rank in terms of energy content?

A → C

Gibb’s Free Energy Indicates Reaction Spontaneity

∆G°ʹ = ∆H°ʹ - T∆S°ʹ

∆G = ∆G°ʹ + RTlnKeq

∆G = ∆H - T∆S

What determines if a reaction is spontaneous in the forward direction reverse direction or at equilibrium?

Entropy (∆S) is a measure of Disorder

Lower Entropy

Higher Entropy

Enthalpy (∆H) is a measure of Heat Content

Negative ∆H → Exothermic reaction

Positive ∆H → Endothermic reaction

What is ∆G, ∆H and ∆S for:

Burning paper? Dissolving (NH4)2SO4 in H2O?

Chapter 1 Problems:

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