Biology 216 - Lect 28 - Bacillus
I. Bacillus - Gm+, sporeforming, large aerobic 
		or facultative rods, rough colonies
	Many produce antibiotics: Bacitracin from B. licheniformis
	Viable spores recovered from amber.
	Examples: 	
	B. subtilis - cloning host
	B. stearothermophilus - autoclave test 
		(resistant and grows best at 80 C)
	B. thurengiensis - spore associated protein
		 (parasporal protein crystal)
		Dissolve lepidopteran gut -> gut liquify -> 
			blood -> paralysis
		Cloned to Ps and to certain plants
	B. sphaericus (effective vs anopheles mosquito)
	B. cereus - food intoxication, large number in food, 
		spore assoicated, diarrhea...
II. B. anthracis - anthrax
	A. Bacteriology - boxcar shape, must differentiate from B. cereus
		Historically  - Koch's postulates; Biological warfare
		1. Spores - Persist in fields for years 
			(record is 60 yrs) - growth in carcass of victim
			Remove carcass, turn under soil, drop below ID50
			Spores in dead tissue (special media needed to see in vitro)
		2. Capsule - protein, single serotype, antiphagocytic
		3. Toxin - 3 components - none alone are toxic; 
			injected together simulates disease - plasmid encoded.
			Lethal factor, edema factor, protective antigen
			a. PA + LF -> CNS respiratory failure, death
			b. PA + EF -> Edema (adenylate cyclase)
			PA probably helps other gain access to cells
			Death by systemic buildup of toxin; Edema, 
			CNS and respiratory failure, hypovolemic, renal..
			Toxins plasmid encoded: Pasteur cured 
				by accident at 42C -> live attenuated vaccine.
	B. Pathogenesis - zoonosis (man gets from diseased animal)
		1. Disease in lower animals - rare in US (occassional outbreak) 
			- economic loss in S. Amer, Afric, Asia
			Outbreaks by tannery (imported hides, elephant ivory) -> 
				human or drain to fields
			Herbivore - ingest spores from soil
			B. anthracis penetrates intestinal mucosa -> 
				bloody diarrhea, septicemia, 80 % fatal
			Death in hours from first symptoms; capillaries of 
				organs engorged with bacteria
				Rarely see bacteria in blood with disease
				 - this is exception; Toxin -> rapid death
		2. Disease in humans - accidental host
			Transmission - contact with infected parts 
				(hides, wool, bone); Rare in US due to animal control
			3 major disease manifestations based upon route of entry:
			a. Cutaneous - single site (95 % of cases in US)
			     Spores through cut, germinate, multiply, itch, no pain
			      Eschar - local edema, induration, 
					dark necrotic center ulcerates, 
					malignant pustule (pathognomonic)
			     Spontaneous healing, loosens, falls off, scar
			b & c. Pulmonary and GI - More severe, less common 
				- similar to animal disease.
			      Considered in biological warfare 
				(US opposes, since cheap and easy for poor country)
	C. Diagnosis
		1. Clinical - Eschar (pathognomonic), 
			history of exposure, occupation
		2. Lab - Direct exam (Gm stain, Fl-Ab)
			Culture and ID (specimen is eschar, sputum) -> 
				BAP, distinguish from B. cereus (biochems)
	D. Treatment
		1. Antibiotics immediately since rapid progression
		2. Excission of lesion contraindicated -> spread
	E. Control
	 	1. Discard infected animal carcasses, turn soil under
		2. Decontaminate imported animal materials (ethylene oxide gas)
		3. Vaccine for animals - effective, but not universally used.
			Live attenuated + toxoid of PA or spore vaccine for animals.