Week 2: Road Map Lecture: (Day 3 & Day 4) • Organic molecules • Diversity of organic molecules:

– Carbon skeleton variations – Functional groups made of SPONCH elements – Complex biomolecules and role of water in their formation-

from single molecules to a complex chain of connected molecules

• Structure and function of each of the 4 complex biomolecules Lab Biochemistry and Macromolecules (Week 2)

Mechanical digestion

Pieces of food

Food

Chemical digestion (hydrolysis)

Nutrient molecules enter body cells

Small molecules

Undigested material

Digestion Ingestion 2 1 Absorption 3 Elimination 4

Atoms/Elements

Molecules

Organelle

Cell

Tissue

Organ

Organ system

Organism (Family)

Population

Community

Ecosystem

Biosphere

Chemical world

Biological World

Non-living

Living

Ascending

Descending

99 % of living material is made of SPONCH atoms

Other vital minerals

Chemical Elements of Biomolecules:

Diversity of organic molecules: variation in length and arrangement of carbon skeletons

Hydrocarbons (Carbon and Hydrogen only)

Functional groups add

to the structural diversity

Female lion

Estradiol

HO

OH

OH

O Testosterone

Male lion

H

OH H OH

H OH

Unlinked monomer

Dehydration reaction

Longer polymer

Short polymer

OH H

H OH

Unlinked monomer

Dehydration reaction

Short polymer

H2O

H

H2O

OH

H OH OH H

Hydrolysis

Synthesis or making

Breakdown or breaking

Role of Water in Polymer Synthesis and Breakdown

Mono- one Di- two Tri- three Tetra- four Penta- five Hexa- six Poly- many

Example of nutritional information on packaged macaroni and cheese

Single Serving %DV

Serving Size 1 cup (228g)

Calories 250

Calories from Fat 110

Total Fat 12g 18%

Trans Fat 1.5g

Saturated Fat 3g 15%

Cholesterol 30mg 10%

Sodium 470mg 20%

Total Carbohydrate 31g 10%

Dietary Fiber 0g 0%

Sugars 5g

Protein 5g

Vitamin A 4%

Vitamin C 2%

Calcium 20%

Iron 4%

Food consists of simple and complex biomolecules Four Groups 1. Carbohydrates: simple sugars & complex carbs 2. Lipids: triglycerides, phospholipids, steroids 3. Protein 4. Nucleic acids: DNA & RNA

Vitamins (other organic molecules) Minerals- chemical elements

Carbohydrates: Simple Sugars • Made of units named saccharides: one unit (mono) or two (di) • Taste sweet because they bind to “sweet” receptors on the

tongue • Broken down and digested very quickly for use as source of

energy • Examples sugars found in: blood, fruit juice, honey, milk, table

sugar, malt

Glucose Fructose Galactose

Sugar Carbohydrate Monosaccharide or disaccharide

Honey Fructose and glucose Monosaccharides

Corn syrup

Glucose Monosaccharide

Fruit sugar

Fructose Monosaccharide

Malt sugar Maltose Disaccharide (glucose and glucose)

Milk sugar Lactose Disaccharide (glucose and galactose)

Beet sugar (cane sugar) Sucrose Disaccharide (fructose and glucose)

Maple syrup Sucrose Disaccharide (fructose and glucose)

Examples of simple sugars and composition

Not all sweeteners are sugars

Aspatame: two connected amino acids (aspartic acid/phenylalanine di-peptide)

Saccharine: C7H5NO3S

Sucralose: chlorinated sucrose

Carbohydrates: Polysaccharides are long chains of many units of simple sugars

• Storage of energy: Starch (plants) and glycogen (animals) • Structures: Cellulose (plant cell walls) and chitin (insect

exoskeletons)

Starch granules in potato tuber cells

Glycogen granules in muscle tissue

Cellulose fibrils in a plant cell wall

Glucose monomer

Cellulose molecules

STARCH

GLYCOGEN

CELLULOSE

O O

O O O O O O

O O O

O O O

O O O O

O O O O

O O

O O O

O O

O O O O O

O O O O O O O

O O O O O O

OH

OH

Proteins: • Polymers of 20 amino acids • Carry out most of the functions of the cell

1. Storage 2. Structural 3. Transport 4. Enzymes 5. Hormones 6. Receptors 7. Contractile

Proteins

• Monomers: 20 called amino acids. • Polymers: polypetides, peptide bonds connect the

amino acids • complex three-dimensional shape or conformation. • May consist of one or more polypeptides

- Amino acid structure: a central carbon connected to • An amino group (NH2) • A carboxyl group (COOH) • An R group, different in each of the 20 different amino acids

- Chemical properties of each amino acid is determined by its R group

H

H

N

H

C

R

C

O

OH

Amino group

Carboxyl (acid) group

Examples of Amino Acids

H

H

N

H

C

CH2

CH

CH3 CH3

C

O

OH

H

H

N C

H

CH2

OH

C

O

OH

H

H

N C

H

C

O

OH CH2

C

OH O

Leucine (Leu) Serine (Ser) Aspartic acid (Asp)

Hydrophobic Hydrophilic

Essential amino acids

Corn

Beans and other legumes Lysine

Tryptophan Isoleucine Leucine Phenylalanine Threonine (Histidine) Valine Methionine

Complementary food combinations

• Essential Amino acids http://www.biology.arizona.edu/biochemistry/problem_sets/a

a/aa.html • Discovering Nutrition - Google Books Result

by Paul M. Insel, R. Elaine Turner, Don Ross - 2005 - Medical - 646 pages

Amino acids are linked together by a peptide bond

H

H N C C

O

OH H

H N + C

H

R

C O

OH H2O

H

H

N C C N C C

R H R OH

O

Peptide bond

Dipeptide Amino acid

Dehydration reaction

Amino group

H

R

Amino acid

Carboxyl group

H O H

Interactions between R groups gives the polypeptide a three dimensional shape

•Some proteins are made of a single polypeptide others of more than one

Collagen is a fibrous protein of three polypeptides that are supercoiled like a rope.

Hemoglobin is a globular protein with two copies of two kinds of polypeptides.

• Physical and chemical conditions affecting the bonds folding the structure of a protein can change its conformation (pH, salt concentration, temperature), or denature it.

Functionally active Functionally inactive

www.pdb.org catalase (7cat)

Lipids - Three major groups of diverse water insoluble (hydrophobic) biomolecules

• Simple fats (glycerides)- long term energy storage (Glycerol + fatty acids)

• Phospholipids- make up cell membranes (Glycerol + fatty acids + phosphate + another group)

• Steroids- regulation (4 fused rings with added functional groups)

Simple Fat: fatty acids joined to glycerol

The same or different fatty acid may be present

Glycerol Fatty Acids

Fatty acids may vary in: - length of hydrocarbon chain (number of carbons). - presence, number, and locations of double bonds.

Saturated fatty acids Unsaturated fatty acids

carbon-carbon double bonds

Absent Present

Physical state at room temperature

Solid Oil

Polyunsaturated fatty acids

Chemical structure of docosahexaenoic acid, or DHA (22:6n-3), and

eicosapentaenoic acid, or EPA (20:5n-3). Enhanced by Neuroinformation

http://lansbury.bwh.harvard.edu/polyunsaturated_fatty_acids.htm http://www.omega3sealoil.com/Chapter2a.html

difference between omega 3, 6, and 9.

Polyunsaturated fatty acids

Key omega-3 and omega-6 fatty acids - found in oily cold-water fish:

tuna, salmon, and mackerel - Fresh seaweed - Plant sources: Leafy greens, nuts, seeds

Omega-9 are not essential in humans

Phospholipids: - Made of glycerol with two attached fatty acids and a

phosphate group connected to a Choline group at the third position

- Major component of the cell membrane

Steroids - carbon skeleton consisting of four fused carbon rings. – cholesterol (component of cell membranes of animal cells) and

some regulatory hormones

Nucleic Acids: Informational biomolecules

• Polymers of nucleotides: deoxyribonucleotides &

ribonucleotides.

• Direct the activities and functions within a single cell.

• Store and transmit hereditary information.

• Two types of Nucleic acids: DNA and RNA.

The monomers of nucleic acids are nucleotides, consisting of :

• sugar • phosphate • nitrogenous base

Sugar

OH

O P O

O−

CH2

H

O

H H

OH H

H

N

N

H N

N H

H H N

Phosphate group

Nitrogenous base (A)

The sugar and phosphate backbone of the nucleic acids or polynucleotides

Sugar-phosphate backbone

T

G

C

T

A Nucleotide

There are 4 nitrogen bases in DNA – A: adenine T: thymine G: guanine C: cytosine

DNA consists of two strands of polynucleotides twisted around each other in a double helix

C

T A

G C

C G

T A

C G

A T

A

G C

A T

A T T A

Base pair

T RNA - single-stranded polynucleotide - contains uracil (U) instead of thymine (T)

– Stretches of nucleotides of a DNA molecule make up genes

– Sequence of nucleotides within genes dictate

the amino acid sequences of proteins

Hereditary Inborn Errors of Metabolism affect Major Biomolecules

Biomolecules Carbohydrates- lactose intolerance Lipids- Familial hyper-cholesterolemia Proteins- Maple Syrup urine disease Nucleic Acids- Lesch-Nyhan Syndrome

Vitamins – Biotinidase deficiency Minerals – Wilson’s disease