CHAPTER 10
Regulation of Gene Expression in Bacteria and Their Viruses
CHAPTER 10
Regulation of Gene Expression in Bacteria and Their Viruses
Copyright 2008 © W H Freeman and Company
CHAPTER OUTLINE10.1 Gene regulation
10.2 Discovery of the lac system: negative control
10.3 Catabolite repression of the lac operon: positive control
10.4 Dual positive and negative control: the arabinose operon
10.5 Metabolic pathways and additional levels of regulation: attenuation
10.6 Bacteriophage life cycles: more regulators, complex operons
10.7 Alternative sigma factors regulate large sets of genes
Regulatory proteins control transcription
Figure 10-2
Allosteric effectors bind to regulatory proteins
Figure 10-3
Repressor protein controls the lac operon
Figure 10-4
Lactose is broken down into two sugars
Figure 10-5
The lac operon is transcribed only in the presence of lactose
Figure 10-6a
The lac operon is transcribed only in the presence of lactose
Figure 10-6b
Structure of IPTG
Figure 10-7
Table 10-1
Operators are cis-acting
Figure 10-8
Table 10-2
Repressors are trans-acting
Figure 10-9
Table 10-3
The repressor contains a lactose-binding site
Figure 10-10
RNA polymerase contacts the promoter at specific sequences
Figure 10-11
The operator is a specific DNA sequence
Figure 10-12
Glucose levels control the lac operon
Figure 10-13
Glucose levels control the lac operon
Figure 10-13a
Glucose levels control the lac operon
Figure 10-13b
Many DNA binding sites are symmetrical
Figure 10-14
Binding of CAP bends DNA
Figure 10-15
CAP and RNA polymerase bind next to each other
Figure 10-16
Negative and positive control of the lac operon
Figure 10-17
Negative and positive control of the lac operon
Figure 10-17a
Negative and positive control of the lac operon
Figure 10-17b
Negative and positive control of the lac operon
Figure 10-17c
Repression and activation compared
Figure 10-18
Repression and activation compared
Figure 10-18a
Repression and activation compared
Figure 10-18b
Map of the ara operon
Figure 10-19
AraC serves as an activator and as a repressor
Figure 10-20
Gene order in the trp operon corresponds to reaction order in
the biosynthetic pathway
Figure 10-21
The trp mRNA leader sequence contains an attenuator region
and two tryptophan codons
Figure 10-22
Abundant tryptophan attenuates transcription of the trp operon
Figure 10-23
Leader peptides of amino acid biosynthesis operons
Figure 10-24
The life cycle of bacteriophage
Figure 10-25
Phage genome is organized for coordinate control
Figure 10-26
Figure 10-27
The lysogenic-versus-lytic cycle is determined by repressoroccupancy on the OR operators
Helix-turn-helix is a common DNA-binding motif
Figure 10-28
Amino acid side chains determine the specificity of DNA binding
Figure 10-29
factors control clusters of unlinked genes
Figure 10-30a
factors control clusters of unlinked genes
Figure 10-30b