Bacterial Genetics
Conjugation:
 
 
 
 
 
 
 
Auxotrophy:
 
 
 
 
 
 
Problems:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Transduction:
 
 
 
 
 
 
Problems
 
 
 
 
 
 
 
 
Tutorial
· Genetic exchange in bacteria
· F+ versus F- cells
· Animation of F+ x F-
· Integration of F+ (animation)
· Hfr strains
· Animation of Hfr x F-
 
Tutorial
· Biochemical pathways
· Gene mutation
· Replica plating video
· Antibiotic markers
· Sugar markers
 
1. Selectable markers
· Amino acid markers
· Antibiotic markers
· Sugar markers
· Replica plates
· Genotypes
 
2. F+, F- and Hfr cells
· Many, few or no recombinants
· Predicting cell type from data
 
3. Interrupted mating
· Selection for exconjugants
· Time of entry
· Map in minutes from origin of transfer
 
4. Natural Gradient of Transfer
· Auxotrophic marker to select against Hfr parent
· Selection of two markers per plate
· Gene order using data
 
5. Multiple Hfrs
· Circular map
 
Tutorial
· Phage Life Cycle (animation)
· Transducing phage
· Donor
· Recipient
· Co-transduction
 
1. Two Factor Crosses
· Co-transduction with five auxotrophic markers
· Co-transduction frequencies
· Gene order
2. Three Factor Crosses (markers in cis)
· Genotype frequencies from replica plates
· Co-transduction frequencies
3. Simulation of Three Factor Cross (markers in trans)
· Choice of donor or recipient strain
· Choice of selectable media
· Replica plate data
· Final map determination
4. Reciprocal Crosses
· Two crossovers vs four crossovers
· Gene order with respect to nearby marker