Microbial Genetics

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Microbial Genetics

• Mutation
• Genetic Recombination
• Model organism
• E. coli
• Molecular Cloning
• Bioinformatics

Golden Rice
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Plasmid Types

• Resistance Plasmids R Plasmids
• Virulence Plasmids
• Bacteriocins
• Engineered Plasmids

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Mutants

• Mutation
• Wild Type
• Genotype
• Phenotype

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Isolation of Mutants

• Replica Plating
• Auxotrophs Nutritional Mutants
• Prototroph
• Wild Type

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Penicillin Selection Method Kills Growing
Cells
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Mutations

• Spontaneous Mutations
• Point Mutations
• Base-Pair Substitution
• Silent,
• Missense, or
• Nonsense Mutations

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Conditional Lethal Mutations

• Temperature Sensitive Mutations

Incubation Temperature
30 C
40 C
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Reading Frame Frame Shift Mutation
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Reversion
Mutation Prototroph Auxotroph Back
Mutation

• Back
• Mutation
• Suppressor
• Mutation

Mutation Back Mutation
Normal Protein
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Other Mutations

• Deletions Lose of a Piece of DNA
• Insertions Additions of a Piece of DNA
• Translocation Movement of a Piece of DNA to a
  New Location in the Genome

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Inversion

• Orientation of a Piece of DNA is Reversed in the
  Genome - Phase Variation

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Mutation Rate

• Spontaneous (Natural or Background) Mutation Rate
• DNA 1 per Million (varies between genes and
  location)
• RNA 1 per Thousand
• Mutagens Anything that Increases the Mutation
  Rate

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Mutagens

• Chemicals
• Base Analogs Chemically Resemble Base

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Intercalating Agent Inserts Between Base Pairs
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• Radiation
• UV Light
• Ionizing Radiation

• DNA Repair
• SOS Regulatory System

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Biological Mutagens

• Transposons Can Insert Into Gene
• Transposon Mutagenesis
• Site Directed Mutations Man-made

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Ames Test

• Mutagens ? Carcinogens
• Ames Test Measures Back Mutation Rates to Detect
  Carcinogens
• Liver extract

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Bacterial Gene Transfer

• Genetic Recombination
• 3 Types of Bacterial Gene Exchange
• 1. Transformation
• Naked DNA
• Competent

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• Transfection in Eukaryotes
• Particle (Gene) Guns Insert DNA
• Electroporation

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2. Transduction

• Generalized Transduction

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Specialized Transduction
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Lysogeny Can Lead to Phage Conversion
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3. Conjugation

• Plasmids
• Copy Number
• Incompatibility
• Curing
• Conjugative Plasmid

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Chromosomal Mobilization

• Fertility (F) Plasmid
• Episome
• HFr Strain
• Sex Pili

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Gene Maps

• Interrupted Matings

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E. coli Chromosome

• 4,639,221 Base Pairs
• 4,288 Open Reading Frames
• 88 ORF
• 1 rRNA, tRNA
• 10 Promoter,
• Origin, etc
• 6 Operons

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Lateral Gene Transfer

• Horizontal Gene transfer
• Pathogenicity Islands
• ICE Integrative and Conjugative Elements

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Transposition

• Transposase
• Conservative Transposition
• Replicative Transposition
• Phase Variation
• Inversion

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Genomics

• Mycoplasma genitalium Genome
• 470 Open Reading Frame
• Genomic Mining

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Genetic Word List
Genotype Phenotypes Wild-Type Isolation
Mutants Replica plating Auxotroph
Prototroph Penicillin-Selection Method
Spontaneous Mutations Point Mutation Base-Pair
Substitution Silent, Missense, Nonsense Mutations
Mutation Genetic Recombination Microbial
Models Molecular Cloning Biotechnology Mutants
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Genetic Word List 2
Temperature Sensitive Mutation Reading
Frame Frame Shift Mutation Back
Mutations Suppressor Mutation
Deletions Insertions Translocation Inversion Mutat
ion Rate DNA 10-6 RNA 10-3
Mutagens Chemicals Base Analogs Intercalating
Agents Radiation UV Light
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Genetic Word List 3
Ionizing Radiation DNA Repair SOS Regulatory
System Biological Mutagens Transposons
Site Directed Mutations Carcinogenesis Ames
Test Genetic Recombination
Bacterial Gene Transfer Transformation Competent T
ransfection Electroporation Particle gun
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Genetic Word List 4
Conjugation Plasmids Copy Number Incompatibility C
uring Conjugative Plasmids
Transduction Generalized Transduction Specialized
Transduction Lysogeny Phage conversion
Resistance Plasmids R Plasmids Virulence
Plasmids Bacteriocin Engineered plasmids
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Genetic Word List 5
Chromosomal Mobilization Sex Pili Fertility (F)
Plasmids HFr Strains Interrupted Matings Genetic
Maps
Escherichia coli Chromosome 4,639,221 Base
Pairs 4,288 Open Reading Frames Horizontal Gene
Transfer
Transposition Transposase Conservative
Replicative Transposition Phase
Variation Inversion
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Genetic Word List 6
Pathogenicity Islands Genomics Mycoplasma
genitalium Genome 470 Open Reading
Frames Genomic Mining