Chapter 13: Bacteria and Viruses Essential question: How do bacteria and viruses affect our lives?

I. Prokaryotes: single celled organisms that do not have nucleus A. Domains: Archaea and Bacteria 1. Bacterial fossils found are about 3.5 billion years old 2. Evolved into many different forms and live in almost every environment

Concept Map Section 19-1 Bacteria Go to Section: are classified into the kingdoms of Eubacteria Archaebacteria include a variety of lifestyles such as live in harsh environments such as Infecting large organisms Thick mud Living in soil Animal digestive tracts Salty lakes Hot springs Go to Section:

B. Classification 1. Domain Bacteria: Kingdom Eubacteria: often called bacteria a) many different shapes and sizes b) shapes: bacilli – rod shaped, cocci-spherical, and spirilla- spiral

c) Gram-negative bacteria: complex cell wall and small amounts of peptidoglycan (protein-carbohydrate compound) d) Gram-positive bacteria: simpler and have more peptidoglycan Gram stain

2. Domain Archaea: Kingdom Archaebacteria: more ancient a) unusual lipids in cell membrane and no peptidoglycan in their cell walls b) live in extreme environments c) methanogens: get energy by changing H2 and CO2 into methane gas d) extreme halophiles: live in high salt concentrations e) thermoacidophiles: acidic and high temperature environments

Archaebacteria at Yellowstone National Park Morning Glory Hot Spring

Grand Prismatic Spring Fumarole with sulfur

Mammoth Hot Springs

Mud Pots

Imperial Geyser

II. Biology of Bacteria A. Structure 1. Cell wall: most bacteria have a cell wall 2. Cell membrane and cytoplasm: lipid bilayer a) carries out cellular respiration b) photosynthesis if it is a photosynthetic bacteria c) cytoplasm: contains ribosomes and DNA

3. Capsules: outer covering that helps to protect bacteria from drying out or harsh chemicals 4. Pili: short, hairlike protein structures helps bacteria cling to host cells Pili 5. Endospores: dormant structure that is produced during harsh environmental conditions 6. Movement structures a) flagella b) glide through slime layer

7. DNA: single closed loop of double-stranded DNA attached to the cell membrane a) plasmid: small circular loops of DNA that carry genes that enable the bacteria to cause disease or resist antibiotics bacteria

The Structure of a Eubacterium Section 19-1 Peptidoglycan Cell wall Cell membrane Ribosome Flagellum DNA Pili Go to Section:

Extra Credit Option : Due Fri. Feb. 12 Watch the movie Contagion Write a summary (paragraph) about the movie by answering the following questions Where did the virus come from (country, animal species, original two people) How was the virus spread? Why did it spread so quickly? Why did it take so long to make a vaccine?

Nutrition and growth 1. Heterotrophs and autotrophs 2. Phototrophs: get energy from light 3. Chemotrophs: get energy from chemicals taken from the environment

4. Four ways a) photoheterotroph: uses light but gets its carbon from organisms b) chemoheterotroph: obtains energy and carbon from other organisms c) photoautotroph: uses light energy and gets carbon from CO2 d) chemoautotroph: energy from compounds and gets carbon from CO2

C. Prokaryotic habitats 1. Obligate anaerobes: cannot survive in oxygen 2. Facultative anaerobes: can live with or without oxygen 3. Obligate aerobes: require oxygen

D. Genetic recombination: three nonreproductive ways that bacteria get new genetic material 1. Transformation: takes in DNA from its environment Transformation 2. Conjugation: two living bacteria bind together and one transfers genetic information to the other Conjugation 3. Transduction: virus obtains DNA from a host and as the viruses replicates inside the bacteria the new DNA is added Transduction

III. Bacteria and Humans A. Bacteria and Disease 1. Pathology: study of diseases 2. Pathogen: bacteria that cause disease 3. Toxins: poisons produced by bacteria that cause disease 4. Bacteria can cause disease by destroying body tissue

Common Diseases Caused by Bacteria Section 19-2 Common Diseases Caused by Bacteria Disease Pathogen Prevention Tooth decay Lyme disease Tetanus Tuberculosis Salmonella food poisoning Pneumonia Cholera Streptococcus mutans Borrelia burgdorferi Clostridium tetani Mycobacterium tuberculosis Salmonella enteritidis Streptococcus pneumoniae Vibrio cholerae Regular dental hygiene Protection from tick bites Current tetanus vaccination Vaccination Proper food-handling practices Maintaining good health Clean water supplies Go to Section:

5. Antibiotics: drugs that combat bacteria by interfering with various cellular functions 6. Antibiotic resistance: bacteria most susceptible to the antibiotic die first, but some are resistant and grow Resistance

B. Useful bacteria 1. Decomposers: break down remains of organic matter in dead plant and animal waste allowing organic compounds to become available to other organisms 2. Used in sewage treatment plants 3. Producing and processing food like sour cream, yogurt, cheese, pickles, and sauerkraut Foods

4. Industrial chemical production: mining for minerals and petroleum, insecticides, cleaning up oil spills

Bacteria Health Pamphlet 1. Title and pictures 2. List several ways to prevent disease 3. Antibiotics used to treat bacterial disease List several ways that bacteria are helpful to humans 5. List several examples of bacterial diseases (p. 472)

IV. Virus Structure A. Virus: nonliving particle composed of DNA or RNA and a protein coat 1. Virology: study of viruses B. Characteristics of viruses 1. One of the smallest biological particles capable of causing diseases

2. Viruses can only replicate by infecting cells and using the cell’s organelles to make new virus particles 3. Made up of nucleic acid (DNA or RNA) and protein coat called capsid 4. Shapes: helical and icosahedral (20 triangular faces) 5. Classified by whether they have RNA or DNA and whether it is singled and double stranded Virus

Virus Structures Section 19-3 Tobacco Mosaic T4 Bacteriophage Virus Influenza Virus RNA Capsid proteins Head Tail sheath DNA Tail fiber RNA Capsid Surface proteins Membrane envelope Go to Section:

V. Viral Replication A. Bacteriophage: viruses that infect bacteria 1. Structure: icosahedral head with tail and tail fibers Bacteriophage B. Lytic cycle lytic 1. Virus invades a host by injecting its DNA 2. Produces new viruses 3. Cell breaks open and releases the new viruses

Figure 19-14 The Lytic Cycle Section 19-3 Bacteriophage protein coat Bacteriophage DNA Bacterial chromosome Bacteriophage attaches to bacterium’s cell wall Bacteriophage enzyme lyses the bacterium’s cell wall, releasing new bacteriophage particles that can attack other cells. Lytic Cycle Bacteriophage injects DNA into bacterium Bacteriophage proteins and nucleic acids assemble into complete bacteriophage particles Bacteriophage Bacteriophage DNA Bacteriophage protein Bacteriophage takes over bacterium’s metabolism, causing synthesis of new bacteriophage proteins and nucleic acids Go to Section:

C. Lysogenic cycle 1. Virus injects DNA into cell 2. DNA integrates into the host cell’s DNA 3. DNA of host cell replicates and so does the virus’s DNA 4. Each bacterial offspring will be carrying the DNA of the virus 5. At some point the cell will go into the lytic phase and destroy the cell Lysogenic

A Lysogenic Infection Section 19-3 Go to Section: Lytic Cycle Bacterial chromosome Bacteriophage DNA Bacteriophage injects DNA into bacterium Bacteriophage DNA (prophage) can exit the bacterial chromosome Lytic Cycle Lysogenic Cycle Bacteriophage DNA (prophage) may replicate with bacterium for many generations Bacteriophage enzyme lyses the bacterium’s cell wall, releasing new bacteriophage particles that can attack other cells Bacteriophage DNA forms a circle Prophage Bacteriophage proteins and nucleic acids assemble into complete bacteriophage particles Bacteriophage DNA inserts itself into bacterial chromosome Go to Section:

VI. Viruses and Human Disease A. Infectious diseases: can affect various organs in the human body including brain, liver, heart, lungs, and skin 1. Common cold, chickenpox, measles 2. Mumps, polio, rabies, AIDS, and hepatitis

3. Some viruses can cause cancer by blocking the normal controls on cell reproduction a) HPV: human papillomarvirus can cause cervical cancer (there is a vaccine for this virus) b) hepatitis B can cause liver cancer

Common Diseases Caused by Viruses Section 19-3 Common Diseases Caused by Viruses Type of Virus Nucleic Acid Disease Oncogenic viruses Retroviruses Adenoviruses Herpesviruses Poxviruses DNA RNA cancer cancer, AIDS respiratory infections chickenpox smallpox Go to Section:

4. Emerging disease: illnesses caused by new or reappearing infectious agents that typically exist in animal populations a) wild and domestic animals can have viruses that can be transmitted to people b) Avian or bird flu is due to close interaction of people and poultry on farms and in markets around the world

B. Prevention and treatment 1. Vaccines: prevent the disease by giving inactive virus to stimulate the body’s immune system to provide protection against the pathogen 2. Antiviral drugs: given to infected patients and it interferes with viral nucleic acid synthesis (very few types of drugs) 3. Antibiotics can not destroy viruses, only bacteria Vaccine

4. 4. Vector control: control of animal vectors that carry the virus a) Mosquito control to stop yellow fever b) Rabies vaccinations to keep pets from of rabies and prevent spread to humans

Virus Research Answer the following questions using the reference books on the lab tables. Research 1 viral diseases. Name of the viral disease Where is it found in the world? Is there a vaccine or way to prevent? What are 2 symptoms of the disease?