Why does Staphylococcus epidermidis not grow on MacConkey agar?
Why does Staphylococcus epidermidis not grow on MacConkey agar?
The pink color of the bacterial growth indicates E. coli is able to ferment lactose. Quadrant 3: Absence of growth indicates the organism, Staphylococcus epidermidis, is inhibited by bile salts and crystal violet and is a gram-positive bacterium.
Does Staphylococcus epidermidis grow on MacConkey agar?
MacConkey agar selects for organisms like Escherichia coli (Gram negative bacilli) while inhibiting the growth of organisms like Staphylococcus aureus (Gram positive cocci).
Is Staphylococcus epidermidis a lactose fermenter?
It is positive for urease production, is oxidase negative, and can use glucose, sucrose, and lactose to form acid products. In the presence of lactose, it will also produce gas.
What agar does Staphylococcus epidermidis grow on?
Staphylococcus epidermidis grows on MSA, but does not ferment mannitol (media remains light pink in color, colonies are colorless). Fig. 8 Staphylococcus epidermidis on Mannitol Salt Agar.
Is Staphylococcus epidermidis Gram-positive or negative?
Gram-positive Staphylococcus
Staphylococcus epidermidis which is known as a coagulase-negative and Gram-positive Staphylococcus, is one of the five significant microorganisms that are located on human skin and mucosal surfaces with the ability of causing nosocomial infections due to the wide usage of medical implants and devices, hence until 1980 …
Can Staphylococcus epidermidis ferment?
While S. epidermidis is a facultative bacterium, it has been reported that it can undergo fermentation under anaerobic conditions (Sivakanesan and Dawes 1980).
What test are used to identify Staphylococcus epidermidis?
Coagulase testing is the single most reliable method for identifying Staphylococcus aureus [9]. Coagulase production can be detected using either the slide coagulase test (SCT) or the tube coagulase test (TCT).
What gram stain is Staphylococcus epidermidis?
gram-positive cocci bacteria
Staphylococcus epidermidis is a coagulase-negative, gram-positive cocci bacteria that form clusters.
What bacteria can grow on MacConkey agar?
MacConkey agar is a selective and differentiating agar that only grows gram-negative bacterial species; it can further differentiate the gram-negative organisms based on their lactose metabolism.