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38 Cards in this Set
- Front
- Back
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What causes spore formation?
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stress from high temperature, pH change, or nutritional limitation
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Identify the Genus:
Gram + rods, motile, catalase +, acid from glucose, foot odor smell |
Bacillus
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Group I, Large Cells
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B. cereus, B megaterium, B. anthracis, B thurigiensis
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group I, Small Cellls
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B. subtilis, B. pumilus, B. licheniformis
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Group II
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B. circulans, B. macerans, B. polymyxa, B stearothermophilus
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Group III
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B. sphaericus
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Protease +, Amylase +, Lipase +
______ ______ |
Bacillus subtilis
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Forms of anthrax
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1. Cutaneous
2. Inhalation 3. Gastrointestinal |
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Cutaneous anthrax:
mode of infection |
enter small cut and germinate. Papule forms at contact site 1-5 days later. Formation of pustule with swelling, center becomes black/necrotic (Eschar).
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Inhalation (sytemic) anthrax:
mode of infection |
Spores taken up by macrophages in the lung, migrate to the lymph nodes and blood stream. Causes septic shock, severe hemorrhaegic fever.
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Gastrointestinal anthrax:
mode of infection |
Ingestion of contaminated meat, rare
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Virulence factors of B. anthracis
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L-alanine - signal that determines germination.
Toxins: Edema and Lethal Capsule: D-glutamate |
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Edema Toxin
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A-B Toxin.
B = Binding A = Edema Factor, adenylate cyclase enters the cell and produces cAMP (disrupts the flow of ions in the cell) |
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Lethal Toxin
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Same B portion
A = Lethal Factor, attack and kill macrophages. Causes shock b/c of production of cytokines. |
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Gram +, sporeforming rods, square ends, subterminal endospores, non hemolytic, non motile, acid from glucose sucrose maltose, salicin -, glycerol -, gelatinase +, growth at 42 C.
____ _____ |
Bacillus anthracis
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Treatment of anthrax
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Penicillin and tetracycline
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Gram + rod, endospore former, motile, acid from glucose maltose salicin, gelatinase +, non encapsulated, B hemolytic
______ _______ |
Bacillus cereus
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Gastroenteritis B. cereus:
mode of infection |
Spores can withstand pasteurization, growth at 4-7 C
Emetic and Entero toxins |
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Emetic toxin
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vomiting, heat stable exotoxin, cereulide, produced during stationary growth phase. Causes swelling of the mitochondria and uncouples oxidative phophorylation.
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Enterotoxin
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profuse watery diarrhea and abdominal cramps. Four different heat stable toxins. Two protein complexes HBL/NHE
Two enterotoxins T and cytotoxin K |
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BT Toxin
____ _____ |
Bacillus thurnigiensis
Ingested as a prototoxin. Trypsin like enzymes converts it to active form. Disrupts cation flow. Encoded in plants, Ti shuttle vector. Mosquitoes and Gypsy Moths |
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Spores used to test autoclaves
_____ _______ |
Bacillus stearothermophilus
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Gram + rods, spore forming, strict anaerobe.
______ _______ |
Clsotridium novyi
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Gram positive rods, spore forming, more tolerant of oxygen
_______ _______ |
Clostridium histolyticum
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Best method to show spores on clostridium
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Inoculate cooked meat agar slant, anaerobic 5-7 days, 30 C
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Isolation of anaerobic bacteria
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No swabs. Anaerobic glove box/Gas Pak System. Inoculate thioglycolate broth and chopped-meat glucose to enhance recovery.
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Gram + rods, oval subterminal endospores, no growth in acid environments salts or nitrite cures.
_____ _______ |
Clostridium botulinum
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What types of botulism cause disease in humans
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A, B, E, F
Neuotoxin |
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Mode of botulinal toxin
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Binds the synaptic vesicles of cholinergic nerves.
Prevents release of acetylcholine Acute flacid descending paralysis |
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Symptoms of food borne botulism
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18-36 hrs incubation
Weakness, dizziness, dry mouth, blurred vision. |
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Gram + rods, terminal endospores, heat labile protein _____ ______
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Tetanospasmin, clostridium tetani
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What type of toxin is tetanospasmin
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Neurotoxin, same mechanism as botulinal toxin, different binding site, spastic paralysis
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Gram + rods, oval central, subterminal, or terminal spores, produces hemolytic lecithinase, splits cell membranes
______ ______ |
Clostridium perfringens
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Causes myonecrosis (Gas Gangrene) and food poisoning
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Clostridium perfringens
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Symptoms of myonecrosis
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rapid invasion and liquefactive necrosis of muscles, gas formation and signs of toxicity
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Foamy diarrhea is a symptom of what?
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Food poisoning caused by C. perfringens
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2 conditions:
Antibiotic Associated Diarrhea Pseudomembranous colitis ________ _________ |
Clsotridium difficile
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Isolation of C. difficile
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Spores isolated from stool using heat shock method.
Plated on medium phenylethyl alcohol blood agar |
