Does Staphylococcus epidermidis grow on pea agar?

Phenylethyl alcohol agar (PEA) is a selective medium used to cultivate Gram positive organisms. Staphylococcus aureus, a Gram positive organism, grows on this PEA plate while Serratia marcescens, a Gram negative organism, does not.

What are most species of bacteria that grow on pea agar?

Specifically, PEA agar is a selective medium that is used for the isolation of gram-positive Staphylococcus species and Streptococcus species from clinical specimens or specimens that contain mixtures of bacterial flora.

What color is Phenylethanol Agar?

Prepared Appearance: Prepared medium is trace to slightly hazy and pale yellow. Prepared medium with 5% sheep blood is red and opaque. Expected Cultural Response: Cultural response on Phenylethanol Agar at 35 ± 2°C and examined for growth after 18 – 48 hours incubation in an aerobic atmosphere.

Does E coli grow on pea?

If used properly, PEA will support good growth of most anaerobes found in clinical infections. PEA should inhibit the growth of facultative anaerobic gram-negative rods, like Escherichia coli and swarming of Proteus mirabilis. Some strains of facultative organisms (which should be inhibited) may grow on PEA.

Why do our pea plates contain 5% sheep blood?

PEA agar with 5% sheep blood is used in microbiology laboratories to inhibit gram-negative bacteria, specificallyProteus species, in specimens containing a mixed bacterial flora (1). Five percent sheep blood is added to the base medium to enhance the growth of anaerobic bacteria.

Would Removing B phenylethyl alcohol from pea?

Would removing b-phenylethyl alcohol from PEA alter the medium’s sensitivity or specificity? It would alter specificity because organisms that “shouldn’t” grow on it would. It wouldn’t likely alter sensitivity because you would probably still be able to detect growth of organisms that “should” grow on it.

What is the purpose of pea agar?

PEA agar is a selective medium that is used for the isolation of gram- positive Staphylococcus species andStreptococcus species from clinical specimens or specimens that contain mixtures of bacterial flora (2). Typically PEA agar is used to inhibit the common contaminants such as Escherichia coli and Proteus species.

What is the purpose of pea test?

Phenylethyl alcohol agar test aka PEA test is performed on a sample of blood to measure the level of Gram Positive Organism in the blood. It is performed to confirm Bacterial Infection and also during the treatment and after the treatment of Bacterial Infection.

What is a pea test?

Phenylethyl alcohol agar test aka PEA test is performed on a sample of blood to measure the level of Gram Positive Organism in the blood. PEA is a selective medium used to cultivate Gram positive organisms.

Is Pea agar A differential?

Phenylethyl Alcohol Agar (PEA) PEA selects for the growth of gram positive organisms by inhibiting the growth of gram negative bacilli. Eosin–Methylene Blue (EMB) Agar is a selective and differential medium used to enhance selection of gram negative bacteria.

Would Removing B phenylethyl alcohol from pea alter the medium sensitivity?

Is MacConkey agar a complex media?

Nutrient broth, tryptic soy broth, and chocolate agar, are all examples of complex media. Selective media are used for the growth of only selected microorganisms. An example of a selective medium is MacConkey agar (Table 9.1 & Figure 9.26).

Why is there a pea plate in agar?

PEA also prevents Proteus species from swarming across the surface of the agar. Staphylococcus aureus, a Gram positive organism, grows on this PEA plate while Serratia marcescens, a Gram negative organism, does not.

How is pea agar used to treat Proteus spp?

PEA agar inhibits the swarming by Proteus spp. and Clostridium septicum. This medium is prepared, dispensed, and packaged under oxygen-free conditions to prevent the formation of oxidized products prior to use.

How does pea inhibit the growth of Gram negative organisms?

The active ingredient, phenylethyl alcohol, inhibits or markedly reduces growth of Gram negative organisms by interfering with DNA synthesis. PEA also prevents Proteus species from swarming across the surface of the agar.

How is pea agar similar to Brucella blood agar?

Morphology of the colonies on PEA are similar to those found on enriched blood agar plates, like Brucella Blood Agar. PEA agar is especially useful in the selective isolation of anaerobes from mixed populations that contain rapidly growing gram-negative bacteria such as Proteus species.