gram positive..
Staphylococcus epidermidis is a gram-positive bacterium and does not ferment lactose. Therefore, on a MacConkey agar plate, S. epidermidis would appear as colorless, indicating a negative result for lactose fermentation. Additionally, there would not be any pink or red colonies representing acid production.
Post ID Special:Contributionssaid: "blue-violet.....because it is a gram-negative bacteria"Wrong...the color is correct, but S. aureus is gram-POSITIVE.
Yes. S. epidermidis is a bacterial species found commonly on the skin as a part of a human's natural bioflora. Sweating releases salt and causes the surface of our skin to be very salty, providing an environment in which many bacteria would normally perish. S. epidermidis, however, prefers such an environment and thus it is also able to grow regularly when cultured on Mannitol Salt Agar plates.
Gramicidin S or Gramicidin Soviet is an antibiotic effective against some Gram positive and Gram negative bacteria as well as some fungi. It is a derivative of gramicidin, produced by the Gram positive bacterium Bacillus brevis. I found the answer from the website of BOC Sciences (bocsci.com)
Gram was a scientist who invented a technique called Gram staining by which bacteria can be colorized and divided into two groups.Gram positiveappearance: blue to transfer to purpleStructure: Have thick layer of peptidoglycan over inner cytoplasmic membrane.They lack LPS-lipopolysaccharides.Gram negativeappearance: pink to transfer to redStructure: In gram negative bacteria the peptidoglycan layer is thinner and is located between space of the outer and inner cytoplasmic membrane.The cell wall contains LPS, which make them virulent.
Staphylococcus epidermidis is a Gram-positive bacterium, meaning it retains the crystal violet stain in the Gram staining procedure. This results in a purple color under the microscope.
Staphylococcus epidermidis is a gram-positive bacterium and does not ferment lactose. Therefore, on a MacConkey agar plate, S. epidermidis would appear as colorless, indicating a negative result for lactose fermentation. Additionally, there would not be any pink or red colonies representing acid production.
In terms of microbiology, S. aureus and S. epi can be differentiated through a number of metabolic tests. The tests being Methyl Red, Vogues-Prauskauer, Mannitol fermentation (of which S. aureus would be + and S. epi - ) and Oxidase (S. aureus - and S. epi + ).
Yes it is. This test can be used to differentiate between S. aureus (which is positive) and S. epidermidis (which is negative).
Metabolic tests such as an oxidase test can be used to differentiate S epidermidis and E faecalis. Such a test can be conducted by adding H2O2 to the colony. The result for S aureus will be negative and the result for S epidermidis will be positive.
S. mitis stains purple and therefore is a gram positive bacteria
S. arureus is a gram posotive cocciScientific classificationDomain:BacteriaKingdom:EubacteriaPhylum:FirmicutesClass:BacilliOrder:BacillalesFamily:StaphylococcaceaeGenus:StaphylococcusSpecies:S. aureus
Frimbriae are structures related to Gram-negative bacteria. S. Pneumoniae, however, is Gram-positive. Therefore it does not have fimbriae.
A 7-day-old culture may appear gram negative, when the organmisms are actually gram positive. Thus, S. epi would appear gram negative, and E. coli gram negative.
MacConkey agar is designed to grow Gram-negative bacteria and also contains crystal violet dye which inhibits the growth of Gram-positive bacteria. Since S. aureus is Gram-positive it should not grow on MacConkey agar. No. MacConkey agar inhibits MOST of the Gram-positive bacteria. There are some Gram-positive bacteria that can tolerate bile-salt are able to grow in MacConkey agar. Enterococcus and some species of Staphylococcus are able to grow in MacConkey. (lack citation though)
Post ID Special:Contributionssaid: "blue-violet.....because it is a gram-negative bacteria"Wrong...the color is correct, but S. aureus is gram-POSITIVE.
The process of gram staining is simple. 1)smear bacteria from pure culture onto slide, heat fix 2)flood with crystal violet (1min) 3)Add iodine (1 min) 4)acid/alcohol wash (1 min) 5)Flood with safranine (1min) 6)Air dry and examine. These times are for clinical microbiology and experimental methods employ optimal and more precise times (but overall its pretty close). Down side of this method is that you must smear bacteria onto the slide and fix it by heating the underside of the slide with a bunsen burner. if they are pink then you have gram negative (Gram's stain didnt stick) if its purple then its gram positive(Gram's stain did stick) This is due to the peptidoglycan layers. Gram negative bacteria have only a thin layer of peptidoglycan as part of the cell membrane/wall where Gram positive have a very think peptidoglycan layer. Source(s): Medical Microbiology