Module 6 Flashcards
What is the cellular morphology of Bacillus anthracis?
Large, straight gram neg rods
Long chains in culture
Spores, but not in living tissue
Capsules in tissue, have to be induced in lab
No flagella
What are the growth requirements for Bacillus?
Facultative anaerobes
35°C optimum but wide range up to 42°C
Nonfastidious
Inhibited by bike salts
What is the cultural morphology of Bacillus anthracis?
BAP- 3-5mm, greyish/white, granular, irregular edge
B. anthracis shows gamma hemolysis (others are beta)
Liquid- surface pellicle, little subsurface growth
What is the ID for Bacillus?
Catalase pos
Nitrate reducing
B. anthracis is nonmotile (the rest are motile)
What is the susceptibility of Bacillus?
B. anthracis- sensitive to penicillin
Others- produce beta lactamase, resistant to penicillin, sensitive to vancomycin
What is the pathogenicity of B. anthracis?
Causes anthrax
Cutaneous- papule, eschar, edema and inflammation
Pulmonary/woolsorter’s disease- spore inhalation, followed by pneumonia
Intestinal
What is the cellular morphology of Bacillus species?
Large gram neg/variable rods
What are the cultural characteristics of Bacillus species?
Grow on nutrient and blood agar
2-5mm, granular with irregular edges, beta hemolysis
Oxidase pos
KOH string test neg (not always)
What is the pathogenicity of B. cereus?
Most strains are motile
Food poisoning
2-6hrs- preformed, heat stable enterotoxin
18hr- heat labile enterotoxin produced in host
Infections in the immunosuppressed
What is B. subtilis used for?
Biological spore control for ethylene oxide gas sterilizer
What is B. stearthermophilus used for?
Biological spore control for autoclave
What is B. thuringiensis used for?
Biological insecticide
What family does the Bacillus genus belong to?
Bacillaceae
