endospore forming bacteria

• What are the main genera of endospore-forming bacteria?

  Bacillus and Clostridium
• What type of bacteria is Bacillus?


  Aerobic or facultative anaerobes
• What type of bacteria is Clostridium?


  Anaerobic
• What distinctive type of dormant cell do endospore-forming bacteria produce?


  The endospore
• Under what conditions are endospores usually formed?


  When a population reaches nutrient limitation
• What are the properties that make endospores highly resistant?


  Resistance to heat, UV, toxic chemicals, and ionizing radiation
• What is the typical habitat of endospore-forming bacteria?


  Soil
• What are the components of the sporulation cycle of Bacillus?


  • Exosporium: thin delicate layer of mostly protein
  • Spore coat(s): multiple layers of spore-specific proteins
  • Cortex: loosely packed peptidoglycan
  • Spore protoplast or core: normal cell wall, plasma membrane, cytoplasm, and nucleoid
• What is the function of dipicolinate in the core of an endospore?


  It protects DNA
• How does the water content of the core compare to that of a vegetative cell?


  The core is dehydrated, containing only 10-30% of the water content of the vegetative cell
• What is the pH of the core compared to the vegetative cell?


  The pH is more acidic than that of the vegetative cell
• What role do small acid-soluble spore proteins (SASPs) play in endospores?


  They provide resistance to dry heat, desiccation, and UV, protecting DNA
• What is the metabolic activity level of the core in endospores?


  Low metabolic activity with low O2 uptake
• What treatments can break the state of dormancy in spores?


  Heat shock or storage at low temperature
• What are the steps of germination for endospores?


  1. Activation
  2. Germination
  3. Outgrowth
• What is the oldest documented age of revived spores?


  25-40 million years old
• What is the significance of the halophilic spore-forming bacterium isolated from salt crystals?


  It may be over 250 million years old
• What is Bacillus anthracis known for?


  It is the agent of anthrax
• How long can Bacillus anthracis spores survive in soil?


  30 years or more
• What are the two types of gastrointestinal anthrax?


  Oral-pharyngeal and abdominal
• What are the symptoms of abdominal anthrax?


  Nausea, severe abdominal pain, vomiting, and bloody diarrhea
• What is the mortality rate for gastrointestinal anthrax?


  Very high
• What is the most common form of anthrax?


  Cutaneous anthrax
• How do spores cause cutaneous anthrax?


  Spores germinate in skin abrasions
• What is the mortality rate for untreated cutaneous anthrax?


  20%
• What happens to spores during pulmonary anthrax?

  Some spores are mopped up by macrophages, while others are trafficked to lymph nodes
• What is the mortality rate for inhalational anthrax in unvaccinated individuals?


  99%
• What is the capsule of Bacillus anthracis made of?


  Poly-D-glutamate polypeptide
• What is the role of the pX02 plasmid in Bacillus anthracis?


  It resists phagocytosis and complement
• What are the components of the toxin encoded on plasmid pX01?


  PA (binding domain), EF (edema factor), LF (lethal factor)
• How is Bacillus anthracis diagnosed?


  By identifying G+ rods with central non-staining spores
• What is the role of the vaccine developed by Pasteur for Bacillus anthracis?


  To provide immunity against anthrax
• What are the three vaccines for Bacillus anthracis?


  • Georgian/Russian vaccine
  • UK vaccine
  • US vaccine
• What is the treatment for Bacillus anthracis infection?


  Penicillin, doxycycline, and fluoroquinolones
• What is Bacillus cereus known for?


  It is one of the most abundant aerobic sporeformers found in soil
• What are the two types of food poisoning caused by Bacillus cereus?


  Short-incubation (emetic) and long-incubation (diarrheal)
• What causes short-incubation food poisoning by Bacillus cereus?


  A heat-stable emetic toxin
• What are the symptoms of short-incubation food poisoning?


  Nausea, vomiting, and abdominal pain
• What causes long-incubation food poisoning by Bacillus cereus?


  An enterotoxin that can be destroyed by cooking
• What are the symptoms of long-incubation food poisoning?

  Diarrhea