polymer synthesis and breakdownfaculty.sdmiramar.edu/bhaidar/bio 130/lectures/biomolecules...
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Biomolecules (Outline)• Structural Hierarchy of the living world• Elements present in biomolecules and terms monomers and polymers• Role of water in making and breaking of polymers. • Food groups the four major complex biomolecules• Name and function of generic monomers and polymers Carbohydrates:
o Chemical elements, simple sugars, and complex carbohydrates. o Structure and function of the following carbohydrates: glucose, glycogen, starch, cellulose,
chitin.Proteins:
o Chemical elements and functional groups. Amino acid and peptide bond, polypeptide, essential and non-essential amino acids
o Multiple functions of proteins and their three dimensional shape o Protein denaturation and loss of function.
Lipids: o Chemical elements and learn their property water insolubility o Three groups of lipids.o Mono-unsaturated and poly-unsaturated fatty acids, essential and non-essential fatty acids.
Nucleic Acids: o Chemical elements and components of a nucleotide. o Structure and function of DNAo 2 types of nucleic acids : DNA and RNA.
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 atomsOther vital minerals
Chemical Elements of Biomolecules:
Diversity of organic molecules: variation in length and arrangement of carbon skeletons
Hydrocarbons (Carbon and Hydrogen only)
HOH 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 OHOH H
Hydrolysis
Synthesis or making
Breakdown or breaking
Role of Water in Polymer Synthesis and Breakdown
Mono- oneDi- twoTri- threeTetra- fourPenta- fiveHexa- six
Poly- many
Example of nutritional information on packaged macaroni and cheese
Single Serving %DV Double Serving %DVServing Size 1 cup (228g) 2 cups (456g)
Calories 250 500
Calories from Fat (Lipid) 110 220
Total Fat 12g 18% 24g 36%
Trans Fat 1.5g 3g
Saturated Fat 3g 15% 6g 30%
Cholesterol (steroid) 30mg 10% 60mg 20%
Sodium 470mg 20% 940mg 40%
Total Carbohydrate 31g 10% 62g 20%
Dietary Fiber 0g 0% 0g 0%
Sugars 5g 10g
Protein 5g 10g
Vitamin A 4% 8%
Vitamin C 2% 4%
Calcium 20% 40%
Iron 4% 8%
Food consists of simple and complex biomolecules
Four Groups 1. Carbohydrates: simple sugars & complex carbs2. Lipids: Fats (triglycerides), phospholipids, steroids3. Protein4. Nucleic acids: DNA & RNA
Vitamins (other organic molecules)Minerals- chemical elements
Inborn Errors of Metabolism affect Major Biomolecules
Clinical Connections 2.1 page, 19Biomolecules
Carbohydrates- lactose intoleranceLipids- Familial hyper cholesterolemiaProteins- Maple Syrup urine diseaseNucleic Acids- Lesch-Nyhan Syndrome
Vitamins – Biotinidase deficiencyMinerals – Wilson’s disease
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
Carbohydrates: Polysaccharides are long chains of manyunits 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
OOOOOO
O O O
OOO
OOOO
OOOO
OO
OOO
OO
OOOO O
OOOOOOO
OOOOOO
OH
OH
Proteins: • Polymers of 20 amino acids• Carry out most of the functions of the cell
1. Storage2. Structural3. Transport4. Enzymes5. Hormones6. Receptors7. 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
Aminogroup
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
OHCH2
C
OH O
Leucine (Leu) Serine (Ser) Aspartic acid (Asp)
Hydrophobic Hydrophilic
Amino acids are linked together by a peptide bond
H
HN C C
O
OH H
HN+ C
H
R
CO
OHH2O
H
HN C C N C C
R H R OH
O
Peptidebond
DipeptideAmino acid
Dehydrationreaction
Amino group
H
R
Amino acid
Carboxyl group
H O H
•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.
• Essential Amino acids
http://www.biology.arizona.edu/biochemistry/problem_sets/aa/aa.html
• Discovering Nutrition - Google Books Resultby Paul M. Insel, R. Elaine Turner, Don Ross - 2005 - Medical - 646 pages
• 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).
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
HN
N H
HHN
Phosphategroup
Nitrogenousbase (A)
The sugar and phosphate backbone of the nucleic acids or polynucleotides
Sugar-phosphatebackbone
T
G
C
T
A NucleotideThere are 4 nitrogen bases in DNA –
A: adenineT: thymineG: guanine C: cytosine
DNA consists of two strands of polynucleotides twisted around each other in a double helix
CTA
GC
C G
T A
C G
A T
A
G C
A TA T
T A
Basepair
TRNA - single-stranded polynucleotide- contains uracil (U) instead of thymine (T)