Chapter 19

The Gram Positive Bacilli

Contents

1.    Critical Thinking Questions

2.    Technical Terms

3.    Internet Sites to Search

1.    Critical Thinking Questions

Bacillus

  • List an aerobic G+ bacterial species that forms endospores
  • List an anaerobic G+ bacterial species that forms endospores
  • Explain some characteristics of the genus Bacillus
  • What is the habitat of Bacillus species?
  • List two species of Bacillus of medical importance
  • What is anthrax? Causative agent?
  • Is the anthrax bacillus found in animals?
  • Where are the majority of anthrax cases reported?
  • Group of people at risk is
  • Explain how does pulmonary anthrax affect a person?
  • What is used in bacteriological warfare?
  • What is gastrointestinal anthrax?
  • Is anthrax controlled easily? How?  
  • Habitat of Bacillus cereus
  • How does its spore affect humans?

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Clostridium

  • Habitat of Clostridium spp in nature
  • How many species in this genus?
  • Extracellular products of this genus
  • Nutritional requirements
  • Main diseases caused by Clostridium species
  • Causative agent of gas gangrene
  • Type of toxins release in gangrene
  • Explain what is alpha toxin
  • Explain how this disease is controlled
  • Which is the 2nd most common intestinal infection in industrialized countries?
  • What is causative microorganism?
  • Are spores present in stools? Why?
  • Causative bacteria for lockjaw
  • How do spores enter the body before tetanus is manifested?
  • Is it a strict anaerobic or is it aerobic?
  • Explain what is tetanospasmin
  • Is this neurotoxin dangerous? If so, why?
  • What the meaning of the term 'risus sardonicus'?
  • Is the vaccine against tetanus effective?  
  • Define botulism
  • Is C. botulinum a spore forming aerobe?
  • Where is habitat?
  • How many types does it have?
  • Types related to human diseases
  • Types related to animal diseases
  • What is the most common food source?
  • Is botulin the most common toxin known?
  • Why is it important to check home-preserved foods?
  • List two measures of prevention  
  • Explain why Listeria monocytogenes is an emerging food-borne pathogen
  • Morphology of Listeria monocytogenes
  • Cause of listeriosis
  • Can you become infected with ice-cream?
  • List a technique to identify Listeria in a laboratory
  • Can it grow in the refrigerator  
  • List three genera that present irregular non-spore-forming rods and are G+
  • Cause of diphtheria
  • Rate of diphtheria in the USA per million of people
  • How do people get sick with diphtheria? (Means of transmission)
  • What is the cause of pathogenecity of Corynebacterium diphtheriae? 
  • What is the agent for acne vulgaris?
  • Where does it reside in our bodies?

Mycobacterium

  • Chemical composition of the cell wall of Mycobacterium
  • What is acid-fastness?
  • What stain is used to identify these bacteria?
  • Are they tolerant to oxygen?
  • Do they grow fast or slow on agar media?
  • Are their colonies pigmented?
  • Number of known species
  • Where do they live in nature?
  • Main two diseases caused by Mycobacterium
  • Define the meaning of the acronym MOTT

Mycobacterium tuberculosis

  • Explain what is a tubercle bacillus
  • Do they grow in sinous masses or strands?
  • How are these strands called?
  • Do they produce exotoxins or enzymes for toxicity?
  • If not, what contributes to their virulence?
  • How do they become intracellular parasites?
  • Percent of infected people that actually develop tuberculosis (tb)
  • 85% of tb occurs in lung. But what about the remaining 15%?
  • Detection methods
  • What is the Mantoux Test?
  • Explain the tuberculin test
  • What does "Ziehl-Neelsen" test refers to?

Mycobacterium leprae

  • Causative agent for leprosy
  • What is the Hansen's Bacillus?
  • Can it be grown in artificial media?
  • If not, how is it grown?
  • Is it a fast growing bacteria?
  • How does it multiply within a human cell?
  • Define leprosy?
  • Is it a transmissible disease?
  • Role of armadillos. Can they pass it to humans (zoonosis)?
  • Incubation period in humans 
  • Do health and living conditions increase risk of acquiring leprosy?
  • Or, is it due to a genetical marker?
  • Is there a vaccine for leprosy? If yes, how effective is it?

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MOTT

  • What is "swimming pool granuloma"?
  • What is the causative bacteria?
  • Define MAC
  • How does it relate to AIDS?
  • Are they opportunistic and nosocomial?
  • Is M. marinum part of MAC?

2.    Technical Terms

  • anthrax
  • endospore
  • spore
  • zoonotic disease
  • pulmonary anthrax
  • cutaneous anthrax
  • anaerobic
  • aerobic
  • rod
  • gas gangrene
  • myonecrosis
  • lecithinase c
  • colitis
  • lockjaw
  • tetanus
  • tetanospasmin
  • risus sardonicus
  • botulism
  • botulin
  • wound botulism
  • listeriosis
  • diphtheria
  • diphtherotoxin
  • toxemia
  • acne vulgaris
  • acid-fastness
  • tubercle
  • MOTT
  • cord factor
  • mycolic acid
  • Mantoux test
  • tuberculin
  • Ziehl Neelsen stain
  • acid-fast stain
  • egg-potato base media
  • Middlebrook media
  • bacille Calmet-Guerin (BCG)
  • MAC
  • leprosy
  • tuberculosis (tb)
     

3.    Search Internet Sites

  • Botulism
  • Gangrene
  • Leprosy
  • Tetanus
  • Tuberculosis