CAMPBELL

BIOLOGYReece • Urry • Cain • Wasserman • Minorsky • Jackson

© 2014 Pearson Education, Inc.

TENTH

EDITION

27Bacteria and

Archaea

Lecture Presentation by

Nicole Tunbridge and

Kathleen Fitzpatrick

Fig. 27-1

Anton van Leeuwenhoek

• Animalcules

Pasteur

• Asepetic technique –

heat treatment

• Fermentation

• Pasteurization

Germ Theory of Disease

• Semmelweis childbirth fever

• Lister aseptic technique for

medicine

• Robert Koch anthrax• “pure” cultures

Koch’s Postulates

• cause-and-effect relationship

between a bacteria (or any other

type of microorganism) and a

clinical disease

• 4 criteria

• Bacteria present in all animals &

isolated from

• Isolated bacteria grown in pure

culture

• Pure culture bacteria inoculated into

healthy host to reproduce

• Re-isolate the bacteria

• Limitations:

• Can’t be grown (leprosy & syphilis)

• No suitable model host

• Multiple causes

• Minor or chronic conditions

Prokaryotes

• DNA not membrane

bound

• Lack membrane bound

organelles

• No histone proteins

• Peptidoglycan

• Widespread

• Size (0.5 – 5 µm)

• Bacteria or Archaea

Reproduction

• Binary Fission

Fig. 27-2

(a) Spherical(cocci)

1 µm

(b) Rod-shaped(bacilli)

2 µm

(c) Spiral

5 µm

Diplo-

Staphylo-

Strepto-

Vibrio

Fig. 27-3

Cellwall

Peptidoglycanlayer

Plasma membrane

Protein

Gram-positive

bacteria

(a) Gram-positive: peptidoglycan trapscrystal violet.

Gram-negativebacteria

(b) Gram-negative: crystal violet is easily rinsed away,revealing red dye.

20 µm

Cellwall

Plasma membrane

Protein

Carbohydrate portionof lipopolysaccharide

Outermembrane

Peptidoglycanlayer

Cell Surface StructuresHans Christian Gram Gram Staining

LPS component•O polysacch antigens for ID (E. coli O157:H7)

•Lipid A endotoxin toxic (fever/shock)

antibiotics

Fig. 27-3c

Gram-positive

bacteria

Gram-negativebacteria

20 µm

AntibioticsAntibiotics target peptidoglycan layer

• Broad spectrum Gram + & - (ampicilin/tetracycline)

• Narrow spectrum specific families

• Both dose, duration & state of invading bacteria

Antibiotics

• Bacteriostatic inhibits or delay growth & repro

• Bactericidal kills bacteria

Fig. 27-4

Capsule

200 nm

Glycocalyx capsule (attachment, prevents, dehydration, provides virulence)

Bacterialcell wall

Fig. 16-2

Living S cells

(control)

Living R cells

(control)Heat-killed

S cells (control)

Mixture of heat-killed S cells and living R cells

Mouse diesMouse dies Mouse healthy Mouse healthy

Living S cells

RESULTS

EXPERIMENT

F. Griffith

1920’s

Transformation

Fig. 27-9

Endospore

0.3 µm

Resting cells Metabolically inactive

survives extreme heat, lack of water,

exposure to many toxic chemicals & radiation

Bacillus & Clostridium

Fig. 27-5

Fimbriae

200 nm

Figure 27.7

20 nmFilament

Hook

MotorCell wall

Plasmamembrane Rod

Peptidoglycanlayer

Flagellum

Chemotaxis (+/-)

Phototaxis (+/-)

Fig. 27-7

(a) Aerobic prokaryote (b) Photosynthetic prokaryote

Thylakoidmembranes

Respiratorymembrane

0.2 µm 1 µm

No complex compartments

Infolding of cell membrane specialized metabolic functions

Internal Organization and DNA

Fig. 27-8

Chromosome Plasmids

1 µm

Internal Organization and DNA

Figure 27.9

1 µm

Plasmids

Chromosome

Internal Organization and DNA

DNA replication, transcription, and translation

differences from eukaryotes?

Binary FissionQuick reproduction – why?

• Small

• Short generation time

• Binary fission

Genetically Diverse (highly variable)

3) Genetic recombination

Horizontal Gene Transfer• Transformation

• Transduction

• Conjugation

1) Rapid reproduction

2) Mutation

Fig. 16-2

Living S cells

(control)

Living R cells

(control)Heat-killed

S cells (control)

Mixture of heat-killed S cells and living R cells

Mouse diesMouse dies Mouse healthy Mouse healthy

Living S cells

RESULTS

EXPERIMENTTransformation

F. Griffith

1920’s

Transformation

Fig. 27-11-4

Recombinant cell

Recipientcell

A+ B–

B–

A+

A–

Recombination

A+

Donorcell

A+ B+

A+ B+

Phage DNA

Figure 27.11-1Phage infects bacterialdonor cell with A+ and B+

alleles.

Donor cell

Phage DNA

A+ B+

1

Transduction

Phage infects bacterialdonor cell with A+ and B+

alleles.

Phage DNA is replicatedand proteins synthesized.

Donor cell

Phage DNA

A+ B+

A+ B+

1

2

Transduction

Phage infects bacterialdonor cell with A+ and B+

alleles.

Phage DNA is replicatedand proteins synthesized.

Fragment of DNA with A+

allele is packaged withina phage capsid.

A+

Donor cell

Phage DNA

A+ B+

A+ B+

1

2

3

Transduction

Phage infects bacterialdonor cell with A+ and B+

alleles.

Phage DNA is replicatedand proteins synthesized.

Fragment of DNA with A+

allele is packaged withina phage capsid.

Phage with A+ alleleinfects bacterial recipientcell.

A+

Donor cell

Phage DNA

A+ B+

A+ B+

A+

B−A−

Crossingover

Recipient cell

1

2

4

3

Transduction

Phage infects bacterialdonor cell with A+ and B+

alleles.

Phage DNA is replicatedand proteins synthesized.

Fragment of DNA with A+

allele is packaged withina phage capsid.

Phage with A+ alleleinfects bacterial recipientcell.

Incorporation of phageDNA creates recombinantcell with genotype A+ B−.

A+

Donor cell

Phage DNA

A+ B+

A+ B+

A+

B−A−

Crossingover

Recombinantcell

Recipient cell

B−A+

1

2

5

4

3

Transduction

Fig. 27-12

Sex pilus 1 µm

Conjugation F factor

Fig. 27-13

F plasmid

F+ cell

F– cell

Matingbridge

Bacterial chromosome

Bacterialchromosome

(a) Conjugation and transfer of an F plasmid

F+ cell

F+ cell

F– cell

(b) Conjugation and transfer of part of an Hfr bacterial chromosome

F factor

Hfr cell A+A+

A+

A+

A+A– A– A–

A– A+

Recombinant

F– bacterium

F Factor & PlasmidsR Factor & Antibiotic resistance

Crossing over

Enzymesdegrade andDNA notincorporated

Table 27-1

• Autotrophs require CO2 as a carbon source

• Heterotrophs require an organic nutrient to make organic compounds

Oxygen Preferences

• Obligate aerobes

• Obligate anaerobes• Clostridium tetani

• C. botulinum

• C. perfringens

• Facultative anaerobes• Staphylococcus

• E. coli

Fig. 27-14

Photosyntheticcells

Heterocyte

20 µm

Nitrogen fixation

Fig. 27-15

1 µ

m

Metabolic cooperation Biofilms – Streptococcus mutans

Fig. 27-UN1

Eukarya

Archaea

Bacteria

Figure 27.15

UNIVERSALANCESTOR

Eukaryotes

Korarchaeotes

Euryarchaeotes

Crenarchaeotes

Nanoarchaeotes

Proteobacteria

Chlamydias

Spirochetes

Cyanobacteria

Gram-positivebacteria

Do

main

Eu

kary

aD

om

ain

Arc

hae

aD

om

ain

Bacte

ria

Table 27-2

Fig. 27-17

Archaea

Fig. 27-20

Symbiosis mutualism, commensalism & parasite

Fig. 27-21

5 µm

Pathogenic bacteria

Pathogenic Bacteria

• Exotoxin• Gram (+)

• Part of growth & metabolism

• Proteins (enzymes) secreted

• Gene location plasmids

• Antitoxins provide immunity

• Types:

» Cytotoxic (diptheria, gangrene)

» Neurotoxins (botulism,tetanus)

» Enterotoxins (cholera, staph)

• Endotoxins• Gram (-)

• Outer portion of cell wall

• LPS

• When Gram (-) dies

• Activates blood clotting

proteins

• Fever & shock

• Bioterrorism (anthrax)

Fig. 27-22

(a)

(b)

(c)

Bioremediation & Technology

Fig. 27-UN3

Fimbriae

Capsule

Cell wall

Circular chromosome

Internalorganization

Flagella

Sex pilus