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What makes a Gram positive bacteria Gram positive?

What makes a Gram positive bacteria Gram positive?

Gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their cell wall .

What does mixed Gram positive flora in urine mean?

If many bacteria, antibiotic treatment may be necessary. In this case they found many different bacteria that are Gram+. Flora means that these are from the skin or gut. That is were they are normally found. If found elsewhere, they can cause an infection. Gram+ bacteria are most often from the skin. Gram- from the gut.

How did Hans Christian Gram classify Gram positive bacteria?

Gram-positive bacteria are bacteria classified by the color they turn in the staining method. Hans Christian Gram developed the staining method in 1884. The staining method uses crystal violet dye, which is retained by the thick peptidoglycan cell wall found in gram-positive organisms.

Why are Gram positive bacteria purple in the microscope?

Gram-positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured when seen through a microscope. This is because the thick peptidoglycan layer in the bacterial cell wall retains the stain after it is washed away from the rest of the sample, in the decolorization stage of the test.

What makes a Gram positive organism Gram positive?

Gram-positive bacteria are bacteria with thick cell walls. In a Gram stain test, these organisms yield a positive result. The test, which involves a chemical dye, stains the bacterium’s cell wall purple. Gram-negative bacteria, on the other hand, don’t hold the dye.

What are examples of Gram positive bacteria?

Examples of gram-positive bacteria are Streptococcus, Clostridium, Lactobacillus, Bacillus subtilis, Leuconostoc, whereas Vibrio, Rhizobium, Escherichia coli, Acetobacter are the example of gram negative bacteria. Cell Wall is single layered, straight, even,…

What is Gram positive in microbiology?

The phrase ‘gram-positive’ is a term used by microbiologist to classify bacteria into two groups (gram-positive or gram-negative). This positive/negative reference is based on the bacterium’s chemical and physical cell wall properties.

Why does Gram positive stay purple?

In Gram stain Gram-positive bacteria remain purple because they have a single thick cell wall that is not easily penetrated by the solvent; gram-negative bacteria, however, are decolorized because they have cell walls with much thinner layers that allow removal of the dye by the solvent.