Ch 11, 19-21

Question 1

Define extremophile

Answer 1

organisms with the ability to thrive in extreme environments.

Question 2

Define methanogen

Answer 2

microorganisms that produce methane as a metabolic by-product in oxygen-limited environments.

Question 3

Define beta-lactamase

Answer 3

diverse class of enzymes produced by bacteria that break open the beta-lactam ring, inactivating the beta-lactam antibiotic. Found in gram (-) bacteria.
Ex. Resistant to penicillin

Question 4

Define M-protein

Question 5

Define buboes

Question 6

Describe the type III secretion system

Question 7

Identify the common features of organisms in the Domain Archaea

Answer 7

Cell type: prokaryote
Cell walls: not peptidoglycan
Cell membranes: phospholipids (may be branched)
Unique rRNA,DNA contains introns, diverse in nutritional and environmental requirements. Ex. Extremophiles, methanogens

Question 8

Sulfolobus
(Archaea)

Answer 8

Acidophile: pH 2
Thermophile: 70 c
Found in sulfur rich hot spring (national parks)
Uses sulfur for respiration instead of oxygen

Question 9

Halobacterium
(Archaea)

Answer 9

Includes: halophile
Grow in salty environment.
Opt: 17-23% salt
Found in great salt lake and solar evaporation ponds for salt manufacture

Question 10

What does bacteriorhodopsin do?

Answer 10

It’s used to harvest sunlight for energy and is alternative to silicon for faster computer chips.
Has a purple pigment
Ex. Phototroph

Question 11

Methanobacterium
(Archaea)

Answer 11

Largest group of archaea that are obligate anaerobes which convert co2/acids into CH4 (methane). Found in marshes, swamps, intestines of animals and marine sediments. Also used in sewage treatment

Question 12

Define biogas

Answer 12

Methane from digestion of sludge, organic waste
Ex. Cow manure, landfill waste

Question 13

Characteristics of bacteria

Answer 13

Cell type: prokaryote
Cell walls: peptidoglycan
Cell membranes: phospholipids that form bilayer but no branching FA’s
Unique rRNA

Question 14

Phylum Firmicutes
(Bacteria)

Answer 14

Low-GC (gram positive), includes endospore formers and bacteria important to health and industry.
Ex. Staphylococcus, streptococcus, Bacillus, and Clostridium.

Question 15

Define toxic shock syndrome and what causes it.

Answer 15

Fever,vomiting,rash, low blood pressure, loss of sheets of skin. Can be caused by leaving tampon in too long due to regular flora that is transferred during insertion.

Question 16

Staphylococcus aureus
(Phylum firmicutes, bacteria)

Answer 16

Causes many human disease (food poisoning to endocarditis) and can cause toxic shock
Key virulence factors- enzyme beta lactamase and toxic shock syndrome toxin -> turns immune cells on inappropriately causing massive immune response that leads to symptoms
Treatment: treat symptoms and antibiotics

Question 17

What does Streptococcus pyogenes cause?
(Phylum firmicutes, bacteria)

Answer 17

Causes: pharyngitis (strep), scarlet fever, rheumatic fever, kidney disease, and rarely necrotizing fasciitis

Question 18

Define rheumatic fever

Answer 18

Auto immune complication of untreated and pharyngitis. Signs include fever, migrating, polyarthritis, migrating rash, and carditis. Common cause is due to a heart valve damage, but has become uncommon in the world world through the antibiotics.

Question 19

Streptococcus pyogenes
(Phylum firmicutes, bacteria)

Answer 19

Key virulence- antiphagocytic factor (capsule) and M-protein.
Treatment - long term antibiotics for infection/prevent recurrence and anti-inflammatory drugs to treat rheumatic fever symptoms

Question 20

Streptococcus mutans
(Phylum firmicutes, bacteria)

Answer 20

40% present in mouth and is found predominantly in the pits and fissures of teeth.
Has fermentative metabolism (produces acid)
Cause dental Caries
Key virulence- produces glycocalyx to attach to cells and produce biofilm

Question 21

What is Dental caries and what is treatment/prevention for it?

Answer 21

Erosion of tooth enamel which can cause pain, difficulty eating, tooth loss, and infection. (Sucrose is glucose + fructose=acid to enamel)
Treatment/prevention - remove all of affected tooth and replace with filling or remove tooth. Brush with fluoride and floss to remove biofilm and change diet (ex. Use xylitol instead of sucrose as S. Mutants can’t use it

Question 22

Lactobacillus
(Phylum firmicutes, bacteria)

Answer 22

Normal flora of digestive/genital system
Fermentative organisms: “Lactic acid bacteria” (produce bacteriocins,H2O2, and LA to kill of pathogens).
May prevent biofilm formation on teeth
Used as probiotic for IBS and gastric ulcers.
Also found in food fermentations ex. Sauerkraut, yogurt, cheese, etc

Question 23

What are the benefits to Lactobacillus to the digestive system?

Answer 23

Production of lactic acid prevents growth of Candida albicans (yeast infection bacteria) and bacterial vaginosis.

Question 24

Clostridium difficile
(Phylum firmicutes, bacteria)

Answer 24

Rod shaped, obligate anaerobe, endospore former and normal flora of gut bacteria. Endospores may be transported by fecal-oral route (C.diff colitis)
Common nosocomial infection caused by long term antibiotic use.
Key virulence factor- TcdA and TcdB toxins that kill colon cells leading to severe inflammation in areas
Treatment- stop antibiotics, fluid and electrolyte replacement and fecal transplant

Question 25

What does Clostridium difficile cause?

Answer 25

Causes watery diarrhea with cramping, and fever. Severe cases can cause lead to death by dehydration or perforation of colon which leads to sepsis

Question 26

Actinobacteria
(Bacteria)

Answer 26

High G+C (gram positive bacteria)
Many are pleomorphic (vary size/shape)
Many have filamentous doesn’t and are common in soil
Include genus: mycobacterium

Question 27

Mycobacterium
(Actinobacteria, bacteria)

Answer 27

Acid fast bacilli, Not very virulent, and transmission/disease rate is low
Treatment: long-term multiple antibiotics
Key virulence: mycolic acid ( survived in dried droplets for 8 months and prevents digestion in phagolysosome of phagocyte)

Question 28

Mycobacterium tuberculosis
(Actinobacteria, bacteria)

Answer 28

Persistent cough with blood and chest pain.
Advanced disease: fever, weakness
Primary - people can live with infection ( most common)
Secondary - can rupture and reinfect

Question 29

Phylum Proteobacteria
(Bacteria)

Answer 29

Named after Greek god proteus (changes shape), gram-negative, lipid A virulence factor. 5 classes; alpha, beta, gamma, delta, and epsilon that are based on 16s rRNA sequences

Question 30

Class Alphaproteobacteria

Answer 30

Capable of growth at low nutrients.
Includes nitrogen, fixers, plant, symbients, pathogens, and the precursors to mitochondria.
Genus : Rickettsia

Question 31

Rickettsia rickettsii
Class Alpha
(Phylum Proteobacterium)

Answer 31

Extremely small obligate (has to live inside cells), intracellular, parasites. Cause rocky mountain spotted fever.
Key virulence factor : enzyme to destroy the phagosome membrane
Treatment : remove chicken, treat with antibiotics (early treatment is key)

Question 32

Bordetella pertussis
Class beta
(Phylum Proteobacterium)

Answer 32

Non-motile aerobic coccobacillus
Causes of whooping cough, vomiting, exhaustion, turning blue, and broken ribs . Key virulence factors: several toxins
Pertusis toxin is an adhesion. Two toxins increase mucus production in tracheal cells, which prevents ciliated movement and kill ciliated cells in trachea. Meaning cells can not sweep out bacterial in paralyzed.
Treatment: tetanus, diphtheria, and Patrias vaccine prevent illness. Mostly treat the symptoms and immune system will kill bacteria. Antibiotics are not usually recommended.

Question 33

Class Betaproteobacteria

Answer 33

Nutrients come from anaerobic decomposition of organic matter

Question 34

Class Gammaproteobacteria

Answer 34

Largest group of proteobacteria
Physiology is varied