251 Lab 9

potable

Coliform bacteria are members of the __________family.

Coliform bacteria

presence of ______indicates the presence of ____ _____ and the possible presence of pathogens

_______and ________media typically select for the growth of gram negative bacteria, inhibiting most gram positive bacteria, and differentiate lactose fermenters (coliforms) from those gram negatives that do not ferment lactose (non-coliforms).

_____ ____ ____contains dyes eosin Y and methylene blue which inhibit gram positive bacteria.

E. coli produces a striking metallic _____sheen due to the excessive _____ production from ____ _____.

Other coliforms produce less acid and turn the medium ___ to dark ____.

___-______are non- pigmented or the color of the medium.

____ ____ _____aims at differentiating Salmonella and Shigella from other enterics.

___ ___ inhibit the growth of most gram positive bacteria

Enterics fermenting any of the three available sugars such as E. coli are typically ____ ____ and non-fermenters, such as Shigella, are typically ___-___.

HEA also has ____ ___ ____ which will react with any H2S produced to form a ____ ferrous sulfide

______ typically produces H2S and colonies will have some ____.

___ ___is also used to differentiate Salmonella and Shigella from other enterics.

MCA contains ___ ___ and crystal violet which ____ gram positives.

The neutral red indictor dye turns lactose fermenters/COLIFORM ____ and the non-fermenters/NON-COLIFORM are ____.

___ ____ _ ___is selective for gram negative organisms and contains a substrate and indicator dye that turns a blue/green color when the colony is expressing the enzyme β-D-galactosidase (GAL).

Rapid E.coli 2 Agar is selective for gram negative organisms and contains a substrate and indicator dye that turns a ___/___ color when the colony is expressing the enzyme _____.

To help distinguish E.coli from other coliforms, Rapid E.coli 2 Agar contains a second enzyme detection system which turns the colony a ___/___ color if the bacteria are expressing the E. coli-specific enzyme _______ in addition to the GAL expressed by all coliforms

On Rapid E.coli 2 Agar the non-coliform gram (-) bacteria will appear ___/___ on the agar. Whereas non-E.coli coliforms will be ___/___ and E.coli will be ___/___.

MacConkey Agar

Eosin Methylene Blue

Hektoen Enteric Agar

Rapid E.Coli 2 Agar

Gram positive cocci include opportunistic pathogens such as _____ _____(typically clusters in a Gram stain) and ____ ____(typically chains in a Gram stain).

They are gram positive cocci, typically in clusters, and are catalase positive.

____ is one enzyme used by aerobic and facultative bacteria that catalyzes this reaction as follows:

The ____test is performed by placing a loopful of the bacterial colony into a drop of ____ ____ and watching for bubble formation.

_____,which is microaerophilic, does not produce catalase.

S.aureus is?

_ _____ may be normal flora of the vaginal tract and is associated with urinary tract infections.

____ ____ is a common member of skin flora but may be associated with hospital acquired blood stream infections

Staphylococcus epidermidis

Mannitol Salt Agar plate colors (MSA)

Blood Agar tests for?