CHAPTER 5
The Genetics of Bacteria
and Their Viruses
Copyright 2008 © W H Freeman and Company
CHAPTER OUTLINE
5.1
5.2
5.3
5.4
5.5
5.6
Working with microorganisms
Bacterial conjugation
Bacterial transformation
Bacteriophage genetics
Transduction
Physical maps and linkage maps compared
Working with microorganisms
Dividing bacterial cells
Chapter 3 Opener
The fruits of DNA technology, made possible by bacterial
genetics
Figure 5-1
Bacteria exchange DNA by several processes
Figure 5-2
Bacterial colonies, each derived from a single cell
Figure 5-3
Distinguishing lac+ and lac- by using a red dye
Figure 5-4
Table 5-1
Model Organism Escherichia coli
Model Organism E. Coli
Bacterial conjugation
Mixing bacterial genotypes produces rare recombinants
Figure 5-5a
Mixing bacterial genotypes produces rare recombinants
Figure 5-5b
No recombinants are produced without cell contact
Figure 5-6
Bacteria conjugate by using pili
Figure 5-7
F plasmids transfer during conjugation
Figure 5-8a
F plasmids transfer during conjugation
Figure 5-8b
Integration of the F plasmid creates an Hfr strain
Figure 5-9
Donor DNA is transferred as a single strand
Figure 5-10
Crossovers integrate parts of the transferred donor fragment
Figure 5-11
Tracking time of marker entry generates a chromosome map
Figure 5-12a
Tracking time of marker entry generates a chromosome map
Figure 5-12b
A single crossover inserts F at a specific locus, which then
determines the order of gene transfer
Figure 5-13
The F integration site determines the order of gene transfer in
HFRs
Figure 5-14
Two types of DNA transfer can take place during conjugation
Figure 5-15
A single crossover cannot produce a viable recombinant
Figure 5-16
The generation of various recombinants by crossing over in
different regions
Figure 5-17
Faulty outlooping produces F´, an F plasmid that contains
chromosomal DNA
Figure 5-18
Table 5-2
A plasmid with segments from many former bacterial hosts
Figure 5-19
An R plasmid with resistance genes carried in a transposon
Figure 5-20
Bacterial transformation
Mechanism of DNA uptake by bacteria
Figure 5-21
Bacteriophage genetics
Structure and function of phage T4
Figure 5-22
Electron micrograph of phage T4
Figure 5-23
Electron micrograph of phage infection
Figure 5-24
Cycle of a phage that lyses the host cells
Figure 5-25
A plaque is a clear area in which all bacteria have been lysed by
phages
Figure 5-26
A phage cross made by doubly infecting the host cell with
parental phages
Figure 5-27
Plaques from recombinant and parental phage progeny
Figure 5-28
Transduction
Generalized transduction by random incorporation of bacterial
DNA into phage heads
Figure 5-29
From high cotransduction frequencies, close linkage is inferred
Figure 5-30
Table 5-3
Transfer of  prophage during conjugation can trigger lysis
Figure 5-31
Transfer of  prophage during conjugation can trigger lysis
Figure 5-31a
Transfer of  prophage during conjugation can trigger lysis
Figure 5-31b
 phage inserts by a crossover at a specific site
Figure 5-32
Faulty outlooping produces  phage containing bacterial DNA
Figure 5-33a
Faulty outlooping produces  phage containing bacterial DNA
Figure 5-33b
Faulty outlooping produces  phage containing bacterial DNA
Figure 5-33c
Physical maps and linkage maps compared
A map of the E. coli genome obtained genetically
Figure 5-34
Part of the physical map of the E. coli genome, obtained by
sequencing
Figure 5-35
Physical map of the E. coli genome
Figure 5-36
Proportions of the genetic and physical maps are similar but not
identical
Figure 5-37
Transposon mutagenesis can be used to map a mutation in the
genome sequence
Figure 5-38