GRAM POSITIVE RODS

What is the unique characteristic of the D-glutamic acid capsule produced by Bacillus anthracis that makes it resistant to host proteolytic enzymes?

• It contains lipid A

• t is highly acidic and destroys host cells.

• It is the “unnatural” form of the amino acid.

• It is non-antigenic.

The lethal factor (LF) of the anthrax toxin, when combined with Protective Antigen (PA), results in which effect?

• Edema

• Massive hemolysis

• Cell & Tissue Death

• Protein synthesis enhancement

Cutaneous anthrax is clinically characterized by a depressed black necrotic central area called a:

• Necrotizing enterocolitis

• Bull’s neck

• black eschar

• Pseudomembrane

In the laboratory diagnosis of Bacillus anthracis, the colony morphology on Blood Agar Plate (BAP) is often described by which term?

• String of pearls

• beaten egg whites

• Molar tooth

• Yellow halo

What is the microscopic arrangement described for Bacillus anthracis where large, square-ended, Gram-positive rods are found in chains?

• Chinese characters

• Drumstick appearance

• Inverted Christmas tree

• Bamboo pole arrangement

Which oral therapy is recommended by the CDC for initial intravenous treatment of B. anthracis infection until antimicrobial susceptibility results are known?

• Penicillin

• Clindamycin

• doxycycline

• Erythromycin

Which characteristic differentiates the diarrheal type of food poisoning caused by Bacillus cereus from the emetic type?

• It is associated with fried rice.

• It has a short incubation time .

• It is caused by a heat labile enterotoxin.

• It is resistant to penicillin.

In contrast to B. anthracis, Bacillus cereus is typically resistant to which common antibiotic?

• Vancomycin

• Clindamycin

• Penicillin

• Ciprofloxacin

Which toxin produced by Clostridium tetani is responsible for increasing excitability of spinal cord neurons and muscle spasm?

• Alpha toxin

• Botulinum toxin

• Tetanospasmin

• Enterotoxin

Clostridium tetani is also known as the Racquet Bacillus due to its round and terminal endospore which gives it what microscopic appearance?

• Chinese characters

• Drumstick appearance

• Oval and subterminal spore

• Bamboo pole arrangement