Download Organic Macromolecules

Bell Ringer
• After swabbing the floor and culturing the
plate for 48hrs at 37 C, you notice that there
was not any growth. Explain why this may
have occurred.
Objectives
• By the end of the lesson, students will be able
to
– Describe basic chemistry principles including
different organic molecules
– By understanding basic chemistry concepts,
you will be able to grasp the various
interactions between a microorganism and its
environment
Organic Macromolecules
• Contain carbon and hydrogen atoms
– Macromolecules – large molecules used by all
organisms
– Lipids
– Carbohydrates
– Proteins
– Nucleic acids
– Monomers – basic building blocks of
macromolecules
© 2012 Pearson Education Inc.
Organic Macromolecules
• Functional Groups – specific chemical
arrangement of atoms
– NH2 amino functional group
– Found in amino acids
– OH hydroxyl functional group
– Found in alcohols
– R (residue) stands for atoms in a compound that
change from one molecule to another
© 2012 Pearson Education Inc.
Organic Macromolecules
• Lipids
– Hydrophobic
– Afraid of, or insoluble in water
• Four groups
– Fats
– Phospholipids
– Waxes
– Steroids
© 2012 Pearson Education Inc.
Organic Macromolecules
• Fats
–Energy stored in covalent bonds
© 2012 Pearson Education Inc.
Organic Macromolecules
• Phospholipids
–The fatty acid tail is nonpolar
–Phospholipid head is polar
–Forms phospholipid bilayer
© 2012 Pearson Education Inc.
Organic Macromolecules
• Waxes
– Contain one long-chain fatty acid
– Insoluble in water
– Mycobacterium tuberculosis is surrounded by a
waxy wall
– Resistant to drying
© 2012 Pearson Education Inc.
Organic Macromolecules
• Steroids
– Four rings fused
– Hormones
– Chemical messengers
– Part of phospholipid
membrane
– Keeps membrane fluid
and flexible at low
temperatures
© 2012 Pearson Education Inc.
Organic Macromolecules
• Carbohydrates
– Composed of carbon, hydrogen, and oxygen
– Functions
– Long and short energy reserve
– Make up DNA and RNA
– Form cell wall
– Cell to cell communication
© 2012 Pearson Education Inc.
Organic Macromolecules
• 1) Monosaccharides
– Simplest sugars
– Deoxyribose
– Glucose
• 2) Disaccharides
– Two monosaccharides linked together
– sucrose (table sugar)
© 2012 Pearson Education Inc.
Figure 2.18 Monosaccharides-overview
Organic Macromolecules
• 3) Polysaccharide
– More than two monosaccharides
– Cellular structure or store energy
– Peptidoglycan – long polymer composing
bacterial cell walls
– Cellulose – cell walls of plants
– Glycogen – energy storage in animal cells
© 2012 Pearson Education Inc.
Figure 2.20 Polysaccharides-overview
Organic Macromolecules
• Proteins
– Mostly composed of C, H, O, N, S
– Functions
– Structure
– Enzymatic catalysis
– Regulation
– Transportation
– Defense and offense
© 2012 Pearson Education Inc.
Organic Macromolecules
• Amino Acids
–
–
–
–
Monomers
21 amino acids
Side groups differ (R) among A.A
Peptide bond links amino acids via dehydration
reaction
© 2012 Pearson Education Inc.
Figure 2.21 Amino acids-overview
Figure 2.23 Linkage of amino acids by peptide bonds
Dehydration
synthesis
Carboxyl Amino
group group
Amino acid 1
Amino acid 2
Peptide bond
Dipeptide
Organic Macromolecules
• Protein Structure
– Structure = function
– 1) Primary structure
– Amino acid sequence
– Combination unique to each protein
– A single change in ONE amino acid can disrupt
function
– 136th amino acid valine replaced with alanine
causes formation of prions
– Proteins spread, causing mad cow disease
© 2012 Pearson Education Inc.
Organic Macromolecules
• Protein Structure
– 2) Secondary structure
– Polypeptide chain folds into α-helices and β-pleated
sheets
– Held together by hydrogen bonds
– 3) Tertiary structure
– folds into 3D shapes
– Held together by ionic bonds, hydrophobic hydrophilic
forces, and disulfide bridges
– 4) Quaternary structure
– Two or more tertiary structures coming together
– Same as tertiary structure forces
© 2012 Pearson Education Inc.
Figure 2.24 Levels of protein structure-overview
Organic Macromolecules
• Protein Structure
–Physical and chemical factors cause loss of
shape = loss of function
– pH changes, extreme hearting, changes in salt
concentrations
– Denaturation – disruption in the 3D structure of
proteins
– temporary or permanent
© 2012 Pearson Education Inc.
Organic Macromolecules
• Nucleic Acids
– DNA and RNA: the genetic material of
organisms
– RNA also acts as enzyme, binds amino
acids, and helps form polypeptides
© 2012 Pearson Education Inc.
Organic Macromolecules
• Nucleic Acids
– Nucleotides are monomers that make up nucleic
acids
– Composed of three parts
– Phosphate
– Pentose sugar
– Nitrogenous bases (A,T,C,G)
© 2012 Pearson Education Inc.
Figure 2.25 Nucleotides-overview
Figure 2.26 General nucleic acid structure-overview
Organic Macromolecules
• Nucleic Acids
– Nucleic acid function
– DNA is genetic material of all organisms and
of many viruses
– Cells replicate and pass on DNA to their
descendants
– RNA helps synthesize proteins
© 2012 Pearson Education Inc.
Practice with Proteins
• With your partners, complete the handouts
over protein structure.
Exit Slip
• 1) List the four main categories of organic
molecules and identify one function for each
molecule.
Friday
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Aseptic Technique Lab
Review safety with Bunsen burner
Purpose of aseptic technique
Aseptic Technique Demonstration