LECTURE 3
® Microorganisms are generally used in studies of
basic metabolic reactions because…
o They are simple organisms which are easy to understand.
o They are inexpensive to maintain for only a matter of minutes in a small space required.
® The substrate and the active site of the enzyme undergo changes to attain an optimal fit.
® Once enzymes used are not part of the reaction, they remain unchanged and can therefore be reused. However, they will eventually deteriorate. That is why we produce enzymes.
® Only has one chromosome and one cell
® Microscopic in size
ENERGY AND CARBON SOURCES
® Chemical Reactions
® Exergonic pathways that break down complex molecules into simpler ones
® Release energy
® Endergonic pathways involved in converting simple molecular building blocks into more complex molecules
® Need energy in order to build
|
® “The enzyme is acting as the lock and has a section called the active site which is where the reaction will take place, and the substrate, for instance a protein, is the key.”
® Specificity
® Shape
® Chemical production is not changed.
® Chemical reactants to which an enzyme binds
® Part of the enzyme
® Where the substrate binds
® Where products are released
|
® Ions that assist enzymes in carrying out, catalyzing, and regulating reactions
® “Helper molecules” that work together with enzymes for biochemical transformation and for the reaction to occur
® Loosely bounded to the catalytic site
® Examples: Calcium and Magnesium
® Combine with enzymes to assist in the catalysis of a reaction
® Carriers
® Examples: Vitamins
|
Apoenzyme
® Inactive (without the cofactor and coenzyme)
® Catalytically active
® Produced and function inside the cell
® Example: Cellulase (fungi cell)
® Need to be released to perform
® Form of non-competitive inhibition
® When inhibitor attaches to allosteric site, it indirectly changes the composition of the enzyme.
® When shape is changed, the enzyme becomes inactive.
® Substrate and active site are not a perfect fit.
® Inhibitor → Enzyme → Altered Active Site →
Reduced Products
® Undoes allosteric inhibition
® When activator attaches to allosteric site, the active site is changed to fit the substrate so it becomes active.
® Activator → Enzyme → Active Site →
Encouraged Products
|
® Essential traits
® Expressed all the time
® Expressed only when needed
® A change in the characteristics of a cell caused by a change in the DNA molecule (genetic alteration) that is transmissible to the offspring.
o Adaptation is not transmissible.
® Enable the organism to be resistant to a particular antibiotic
® Found in plasmids
® Develop resistance to antibiotics
® Lead to nonfunctional enzyme (no metabolic process occurring)
® Lethal mutations
® No effect
® Agents that affect chromosomes
o UV light (physical)
o
|
Chemicals
® Organism containing the mutation
|
® Alters the enzyme
® No need for more production
® Enzyme 1 → Substrate A → Enzyme 2 → Substrate B → Enzyme 3 → End Product → Put to a Halt
® Genetic material is floating on the cytoplasm.
® One chromosome
® Plasmid: Main chromosome and may integrate with chromosome (episome)
® Used in genetic and medical research
|
® OPV
o Discovered by Sabin
o 2 drops
o Oral polio vaccine: weakened virus
o Mouth → digestive tract
o Intestine (protection)
o Waste excreted
o Protects you and people around you (herd community)
1)
|
Replication: DNA unwinds
2) Transcription: DNA → RNA
A | A | C | G | T | A | C | G | A | T | T | A | G |
↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ |
U | U | G | C | A | U | G | C | U | A | A | U | C |
|
3 Codons
® IPV
o Discovered by Salk
o Inactivated: Injected
o Blood
o Safe and effective
o Protects only you
® Single-stranded
® Ribose sugar
3) Translation: RNA → proteins → amino acids
A – Adenine → Thymine → U
C – Cytosine → Guanine G – Guanine → Cytosine T – Thymine → Adenine
® Genotype: Alleles (representation)
® Phenotype: Traits or Physical Characteristics
® Fresh DNA
® Take genomes or naked DNA and use it
® Raw naked DNA: encodes for antibiotic resistance into this medium (own chromosome/plasmid)
® Typically between bacteria of the same or closely-related species with Transduction
® Antibiotic resistant
o Degrades the DNA
o Bacteria will not be able to use it
® “Pick and crop”
® DNA transferred through bacteriophage (viral bacteria): carrying its own DNA will inject this DNA into the bacteria
® Viral DNA will be integrated into the bacterial DNA and replicate the virus
® Bacterial Death: Packaging (Lytic Phage: generalized) – whole genetic material being acquired
® Exotosin Production: Excision (Lysogenic Phage: specialized) – specific genetic material being acquired
® “Jumping genes” (transposons)
o Sequence transfer: Altered DNA material
o Encoded by plasmids or transposons
o Most common (?)
® Sex pilus: F+
® No sex pilus: F-
o F+ will link with the F- bacteria (mating bridge: direct contact)
o F+ will make a copy of its plasmid and will transfer to other bacteria
® Plasmid
® 2 Bacterial DNA: Chromosomes or plasmids
® Part of bacterial DNA from chromosome to plasmid (smaller and readily accessible), and vice versa
® Only plasmid can be shared with another bacteria
® Temperate
® Bacteria + bacteriophage (only its DNA material is transferred)
® Virus → Cell
® Microorganisms are generally used in studies of
basic metabolic reactions because…
o They are simple organisms which are easy to understand.
o They are inexpensive to maintain for only a matter of minutes in a small space required.
® The substrate and the active site of the enzyme undergo changes to attain an optimal fit.
® Once enzymes used are not part of the reaction, they remain unchanged and can therefore be reused. However, they will eventually deteriorate. That is why we produce enzymes.
® Only has one chromosome and one cell
® Microscopic in size
ENERGY AND CARBON SOURCES
® Chemical Reactions
® Exergonic pathways that break down complex molecules into simpler ones
® Release energy
® Endergonic pathways involved in converting simple molecular building blocks into more complex molecules
® Need energy in order to build
|
® “The enzyme is acting as the lock and has a section called the active site which is where the reaction will take place, and the substrate, for instance a protein, is the key.”
® Specificity
® Shape
® Chemical production is not changed.
® Chemical reactants to which an enzyme binds
® Part of the enzyme
® Where the substrate binds
® Where products are released
|
® Ions that assist enzymes in carrying out, catalyzing, and regulating reactions
® “Helper molecules” that work together with enzymes for biochemical transformation and for the reaction to occur
® Loosely bounded to the catalytic site
® Examples: Calcium and Magnesium
® Combine with enzymes to assist in the catalysis of a reaction
® Carriers
® Examples: Vitamins
|
Apoenzyme
® Inactive (without the cofactor and coenzyme)
® Catalytically active
® Produced and function inside the cell
® Example: Cellulase (fungi cell)
® Need to be released to perform
® Form of non-competitive inhibition
® When inhibitor attaches to allosteric site, it indirectly changes the composition of the enzyme.
® When shape is changed, the enzyme becomes inactive.
® Substrate and active site are not a perfect fit.
® Inhibitor → Enzyme → Altered Active Site →
Reduced Products
® Undoes allosteric inhibition
® When activator attaches to allosteric site, the active site is changed to fit the substrate so it becomes active.
® Activator → Enzyme → Active Site →
Encouraged Products
|
® Essential traits
® Expressed all the time
® Expressed only when needed
® A change in the characteristics of a cell caused by a change in the DNA molecule (genetic alteration) that is transmissible to the offspring.
o Adaptation is not transmissible.
® Enable the organism to be resistant to a particular antibiotic
® Found in plasmids
® Develop resistance to antibiotics
® Lead to nonfunctional enzyme (no metabolic process occurring)
® Lethal mutations
® No effect
® Agents that affect chromosomes
o UV light (physical)
o
|
Chemicals
® Organism containing the mutation
|
® Alters the enzyme
® No need for more production
® Enzyme 1 → Substrate A → Enzyme 2 → Substrate B → Enzyme 3 → End Product → Put to a Halt
® Genetic material is floating on the cytoplasm.
® One chromosome
® Plasmid: Main chromosome and may integrate with chromosome (episome)
® Used in genetic and medical research
|
® OPV
o Discovered by Sabin
o 2 drops
o Oral polio vaccine: weakened virus
o Mouth → digestive tract
o Intestine (protection)
o Waste excreted
o Protects you and people around you (herd community)
1)
|
Replication: DNA unwinds
2) Transcription: DNA → RNA
A | A | C | G | T | A | C | G | A | T | T | A | G |
↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ | ↓ |
U | U | G | C | A | U | G | C | U | A | A | U | C |
|
3 Codons
® IPV
o Discovered by Salk
o Inactivated: Injected
o Blood
o Safe and effective
o Protects only you
® Single-stranded
® Ribose sugar
3) Translation: RNA → proteins → amino acids
A – Adenine → Thymine → U
C – Cytosine → Guanine G – Guanine → Cytosine T – Thymine → Adenine
® Genotype: Alleles (representation)
® Phenotype: Traits or Physical Characteristics
® Fresh DNA
® Take genomes or naked DNA and use it
® Raw naked DNA: encodes for antibiotic resistance into this medium (own chromosome/plasmid)
® Typically between bacteria of the same or closely-related species with Transduction
® Antibiotic resistant
o Degrades the DNA
o Bacteria will not be able to use it
® “Pick and crop”
® DNA transferred through bacteriophage (viral bacteria): carrying its own DNA will inject this DNA into the bacteria
® Viral DNA will be integrated into the bacterial DNA and replicate the virus
® Bacterial Death: Packaging (Lytic Phage: generalized) – whole genetic material being acquired
® Exotosin Production: Excision (Lysogenic Phage: specialized) – specific genetic material being acquired
® “Jumping genes” (transposons)
o Sequence transfer: Altered DNA material
o Encoded by plasmids or transposons
o Most common (?)
® Sex pilus: F+
® No sex pilus: F-
o F+ will link with the F- bacteria (mating bridge: direct contact)
o F+ will make a copy of its plasmid and will transfer to other bacteria
® Plasmid
® 2 Bacterial DNA: Chromosomes or plasmids
® Part of bacterial DNA from chromosome to plasmid (smaller and readily accessible), and vice versa
® Only plasmid can be shared with another bacteria
® Temperate
® Bacteria + bacteriophage (only its DNA material is transferred)
® Virus → Cell
