a motile, facultatively anaerobic Gram-negative rod . It ferments sucrose and mannitol, is positive for ONPG, indole, lysine decarboxylase, and esculin hydrolysis, and negative for ornithine decarboxylase.

**can be distinguished by its lack of color in MACCONKEY

Causes myonecrosis (a gas gangrene-like infection)that can quickly lead to bacteremia and systemic toxicity. Mortality rates are high among leukemia, lymphoma, and otherwise immuno-

suppressed patients following sepsis.

“weaponized” bacteria-- used in World war

Describe Bacillus anthracis

responsible for toxin and capsule production in Bacillus anthracis

virulence factors of Bacillus anthracis

toxin responsible for the necrotic lesions (eschars) surrounded by large areas of swelling in cutaneous anthrax.

is a protease that interferes with cytokine production, neutrophil chemotaxis, and macrophage survival—all of which compromise the immune system and

allow rapid multiplication of the pathogen.

facultatively anaerobic, nonmotile, encapsulated, endospore-forming, Gram-positive rod . It will not grow on phenylethyl alcohol

blood agar, is catalase-positive, and gelatinase-negative.

typically produces large, gray, rough-textured colonies on Sheep Blood Agar. It is nonhemolytic. It causes anthrax

It is responsible for two types of food poisoning

and severe ocular infections.

Toxins found in B. cereus

It is caused by heat-stable enterotoxin, appears one to six hours after exposure, and typically lasts less than 24 hours. It most frequently appears in cooked rice that has not been

properly refrigerated. The spores that survive the initial

cooking germinate and multiply rapidly, releasing toxin that is not destroyed by further cooking.

caused by heat-labile enterotoxin, appears approximately

nine hours after exposure, and typically lasts 24 to 36 hours. Foods that cause __________ are meat, vegetables, and sauces.

motile, facultatively anaerobic, endospore-forming, Gram-positive rod . It produces acid from glucose, maltose, and salicin fermentation, and is lecithinase- and gelatinase-positive. Diagnostic procedures include Gram stain and aerobic culture.

raised, dull, gray colony morphology ON SHEEP BLOOD AGAR

is the cause of the disease known as pertussis or “whooping cough,” characterized by violent coughing, vomiting, and gasping for breath.

**(Class Betaproteobacteria)

reside in the human gastrointestinal tract and, to a lesser extent, in the female genital tract.

responsible for the majority of intra-

abdominal infections and is recovered from most other human infections.

a pleomorphic, encapsulated, nonmotile, an-aerobic, Gram-negative rod . It varies in size from 1.5 to 6 m long. It does not ferment arabinose, melezitose, or salicin, but grows well in the presence of 20% bile, is indole-negative, and catalase-positive (unusual for an anaerobe).

It can infect anyone with no immunity or diminished

immunity, but is most severe and communicable among

infants less than one year of age.

Humans are the exclusive host of this organism, and asymptomatic or unrecognized

symptomatic adults are the likely reservoirs.