PPT1 E. coli

What does E. coli use for its characteristic MOTILITY?

Flagella

Which structures aid E. coli in adhering to host cells?

Fimbriae

Which part of the E. coli is used for DNA transfer via conjugation?

$ex pilus

How do E.coli appear on MAC agar?

PINK (lactose fermenting)

What kind of hemolysis can some strains of E. coli show on SBA?

Beta hemolysis

What are the 3 antigens associated with E. coli?

O, H, K

Where are the O antigens found?

Outer surface

Where are the H antigens found?

flage l-l a

Where are the K antigens found?

Kapsule (capsule)

How does E. coli typically appear on MAC?

Lactose fermenters

DRY PINK colonies on MAC

What is the different variant seen on MAC for E. coli?

MUCOID variant

What does PALE growth on MAC indicate?

Non-lactose fermenting E. coli strains

What is IMVC?

Biochemical Identification

I = Indole

M = Methyl red

V = Voges-Proskauer

C = Citrate

What is the typical IMVC pattern of E. coli?

+ + - -

In the Indole for IMVC, which enzyme converts tryptophan to indole, producing a pink color?

Tryptophanase

+ in E. coli

In the Methyl red for IMVC, what is the principle?

Checks if the bacteria ferments:

Glucose → mixed acids

+ in E. coli

In the Voges-Proskauer for IMVC, what is this test detecting for?

Detecting if the organism ferments glucose to ACETOIN

In the Citrate for IMVC, what is being tested for?

Detecting if the organism utilizes CITRATE FOR ENERGY

What 4 sugars can E. coli ferment?

Glucose (Methyl red+), LACTOSE (MAC +), Xylose, Trehalose

What values does E. coli have on Oxidase, H2S production, and Urease?

Oxidase -

H2S -

Urease -