Bacteria Lab Characteristics

Question 1

Corynebacterium Diptheriae

Answer 1

Gram-positive rods, metachromic (blue and red) granules that stain with aniline dyes like methylene blue, Elek test for toxin

Question 2

Pseudomonas Aeruginosa

Answer 2

Gram-negative rods, lactose nonfermenter, oxidase positive, pyocyanin (blue green pigment), grape like odor

Question 3

Shigella

Answer 3

Gram-negative rods, lactose nonfermenter, oxidase negative, propel by actin polymerization

Question 4

EHEC (Enterohemorrhagic E. Coli - 0157:H7)

Answer 4

Gram-negative rods, fast lactose fermenter, does not ferment sorbitol, does not produce glucuronidase

Question 5

ETEC (Enterotoxigenic E. Coli) - Type 1

Answer 5

Gram-negative rods, fast lactose fermenter

Question 6

ETEC (Enterotoxigenic E. Coli) - Type 2

Answer 6

Gram-negative rods, fast lactose fermenter

Question 7

Yersinia Enterocolitica

Answer 7

Gram-negative rods, lactose nonfermenter, oxidase negative, propel by actin polymerization

Question 8

Bacillus anthracis

Answer 8

Gram-positive, aerobic, spore forming rod, only bacterium with polypeptide capsule (D-glutamate), long chains (“medusa head”)

Question 9

Vibrio cholerae

Answer 9

Gram-negative (pink), oxidase positive, comma shaped, grows in alkaline media (sensitive to gastric acidity)

Question 10

Bordetella Pertussis

Answer 10

Gram-negative, “coccoid” rods, Bordet-Gengou (potato) agar

Question 11

Clostridium Tetani

Answer 11

Gram-positive, spore-forming, obligate anaerobe

Question 12

Clostridium botulinum

Answer 12

Gram-positive, spore-forming, obligate anaerobic bacteria

Question 13

Clostridium perfringens

Answer 13

Gram-positive, spore-forming, obligate anaerobe, double zone of hemolysis on blood agar

Question 14

Mycobacterium leprae

Answer 14

Gram-positive, bacilus, acid fast, no growth in vitro

Question 15

EIEC (Enteroinvasive E. Coli)

Answer 15

Gram-negative rods, fast lactose fermenter

Question 16

EPEC (Enteropediatric E. Coli)

Answer 16

Gram-negative rods, fast lactose fermenter

Question 17

Haemophilus influenzae

Answer 17

Gram-negative (pink), coccoid rods, requries V factor (NAD+ provided by S. Aureus) and X factor (hematin) for growth on sheep agar

Question 18

Pasturella

Answer 18

Gram-negative pleomorphic, facultative anaerobic, catalase positive, oxidase positive

Question 19

Brucella

Answer 19

Gram-negative, coccoid rods

Question 20

Neisseria Gonorrhoeae

Answer 20

Gram-negative cocci, maltose nonfermenter, no polysaccharide capsule, grows on Thayer-Martin medium (VPN - vancomycin, polymixin, trimethoprim)