The Endospore forming bacteria

Question 1

What are the Two main genera of the endospore forming bacteria?

Answer 1

• Bacillus
• Clostridium

Question 2

When are endospores usually formed?

Answer 2

• Usually formed when a population reaches conditions of nutrient limitation

Question 3

What are the features of endospores

Answer 3

• Highly resistant to heat, uv, toxic chemicals, ionising radiation
• Heat resistance is used for selection

Question 4

Where are endospores usually found?

Answer 4

• Typically Gram + cell wall

Question 5

What is the typical habitat for endospores?

Answer 5

• Soil

Question 6

does endospores stain gram + or -

Answer 6

• typically gram + but stain variably

Question 7

Is Bacillus aerobic or anaerobic

Answer 7

• Aerobic or facultative anaerobes

Question 8

Is Clostridium aerobic or anaerobic

Answer 8

• Anaerobic

Question 9

Name the different layers of endospores from outside to in

Answer 9

• Exosporium
• Spore coat(s)
• Cortex
• Spore protoplast or core

Question 10

What is the exosporium of an endospore

Answer 10

• The outside layer of an endospore
• thin delicate layer of mostly protein

Question 11

What is the Spore coat(s) of an endospore

Answer 11

• Multiple layers of spore-specific proteins

Question 12

What is the Cortex of an endospore

Answer 12

• loosely packed peptidoglycan
• one of the layers of an endospore

Question 13

What is the Spore protoplast or core of an endospore

Answer 13

• normal cell wall, plasma membrane, cytoplasm and nucleoid

Question 14

Name the features of Bacillus. (aerobic or anaerobic, gram stain, habitat)

Answer 14

• Aerobic or facultative anaerobes
• Variable gram stain
• Habitat: mainly soil organisms, although some parasites and pathogens

Question 15

I am an agent of anthrax, disease of sheep, goats and cattle, that is also transmissable to humans and survive in soil for 30 years or more what am I

Answer 15

• Bacillus anthracis

Question 16

What are the 3 main general manifestations/routes of infection of human Bacillus anthracis

Answer 16

• Cutaneous Anthrax (animal workers)
• Gastrointestinal Anthrax (ingestion of contaminated meat)
• Pulmonary anthrax (inhalation of spores)

Question 17

What is Cutaneous Anthrax

Answer 17

• most common form of infection out of the 3
• Spores germinate in skin abrasions
• Skin ulcer - black eschar, can become systemic

Question 18

What type of workers usually catch cutaneous antrax

Answer 18

• Animal workers

Question 19

What is the mortality rate of cutaneous anthrax

Answer 19

• untreated is 20% mortality

Question 20

what is cutaneous anthrax treated with

Answer 20

• responds well to antibiotics

Question 21

What is Gastrointestinal Anthrax

Answer 21

• ingestion of undercooked contaminated meat

Question 22

what are the two types of Gastrointestinal Anthrax

Answer 22

• oral- pharyngeal (most rare) and abdominal (rare)

Question 23

What happens when you get abdominal gastrointestinal anthrax

Answer 23

• Spores germinate in lower gastrointestinal tract
• primary intestinal lesions form

Question 24

A guy ingested undercooked contaminated meat and showed signs of nausea, severe abdominal pain, vomiting, blood diarrhea. What did he get?

Answer 24

• Gastrointestinal Anthrax

Question 25

What is Pulmonary anthrax

Answer 25

- inhalation of spores - spores are mopped up by macrophages and some trafficked to draining lymph nodes

Question 26

What is the mortality of pulmonary anthrax

Answer 26

- 80% mortality in 2-4 days whether antibiotics are given or not - 99% lethal in unvaccinated individuals

Question 27

someone had inhaled some spores and has mild upper respiratory tract infection, a few dys later the persons health rapidly deteriorates with severe breathing problems and shock what is this a sign of?

Answer 27

- Pulmonary anthrax

Question 28

What is the treatment for Bacillus anthritis

Answer 28

- penicillin, doxycycline and fluoroquinolones

Question 29

What are the preventions for bacillus anthritis

Answer 29

- Vaccines - Bacillus anthrax lacks plasmid pX02 which encodes the protective coating of the bacteria

Question 30

What is Bacillus cereus and what are the two types

Answer 30

- food poisoning - Short incubation/emetic or long incubation/diarrheal

Question 31

What is short-incubation/emetic bacillus cereus

Answer 31

- occurs 1-6 hours of eating - symptoms often include nausea, vomiting, and abdominal pain - caused by heat stable emetic toxin which cannot be destroyed by cooking

Question 32

What is long-incubation/diarrheal bacillus cereus

Answer 32

- occurs 6-18 hours after eating - symptoms = diarrhea -caused by enterotoxin that can be destroyed by cooking

Question 33

What is the habitat of Clostridium

Answer 33

- Widely distributed in nature, soil, water, and intestinal tract of animals

Question 34

Where is Clostridium Botulism habitat

Answer 34

- found in soil, water and decaying vegetation

Question 35

What is Clostridium Botulism

Answer 35

- fatal food poisoning that follows ingestion of preformed toxin from growth of organism in food

Question 36

How does Clostridium Botulism spread

Answer 36

- endospores are very resistant to heat and may withstand boiling for several minutes - animals are frequently affected from feeds - Anaerobic conditions may germinate spores - grow into vegetative cells and eventually produce the deadly toxin

Question 37

How does Clostridium Botulinum toxin work

Answer 37

- Toxin acts by inhibiting release of acetylcholine form motorneurons causing flaccid paralysis - Toxin (Botox) can be used clinically to relieve muscle contractions or cosmetically

Question 38

Clostridium botulism may occasionally infect what ?

Answer 38

- Wounds

Question 39

What is the diagnosis of clostridium botulism ?

Answer 39

- ELISA for toxin in food or suspect food is injected into mice

Question 40

How are toxins produce for Clostridium tetani

Answer 40

- Spores enter body through wound - wounding produce necrotic (dead) cells allow anaerobic conditions to develop and spores to germinate leading to formation of the toxin

Question 41

What are the two different types of tetanus (Clostridium tetani)

Answer 41

- Generalised tetanus - Neonatal tetanus

Question 42

What is the pathogenesis of clostridium tetani

Answer 42

- toxin migrate along peripheral nerve axons to teh central nervous system - symptoms take 3-21 days to develop

Question 43

patient suffers from spastic paralysis which involve neck and jaw, their body is severely contorted what are they suffering from

Answer 43

- clostridium tetani

Question 44

Where can you find Clostridium perfringens

Answer 44

- normal flora in GI and vagina

Question 45

what causes gas gangrene

Answer 45

- Clostridium perfringens spores contaminating wounds - several other species of clostridia may also cause gangrene

Question 46

What happens when clostridium perfringens contaminate wounds

Answer 46

- after germination organisms screte exotoxins causing more tissue damage, resulting in rapid spread of the organisms

Question 47

What is the diagnosis and identificaiton of clostridium perfringens

Answer 47

- black rotten look - x ray for gas - rancid smell on meat media

Question 48

Clostridium perfringens prevention and treatment

Answer 48

- cleansing of wounds - antibiotics have littl eeffect in necrotic areas - surgery maybe necessary to remove affected parts