Gram Positive Bacteria

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By: Milton Antwi
THE DIFFERENCES BETWEEN THE TWO MAIN TYPES OF BACTERIAL SPECIES The core difference between a gram positive bacteria and gram negative bacteria is the differences in cell wall composition. Prokaryotes known as eubacteria have three basic forms: rods, cocci and spiral. The bacterial cell wall is the single most important contributor to cell shape. In addition to shape of cell wall, presence or absence of flagellum, and if present, positions of flagellum, the eubacteria can be classified according to Gram Stain. First and foremost, gram positive bacteria are by and large dark, blue and dark purple shades when they endure a process of straining. Their basic features are examined on the basis of their cytoplasmic lipid membrane, cell wall, and finally the presence of the bacteria in the cystol. Gram positive bacteria are mainly composed of a capsule polysaccharide, thick peptidoglycan layer, and flagellum which are present in certain species. It can either be aerobic or anaerobic. Gram positive bacteria have a simpler cell wall, with a large amount of peptidoglycan. Peptidoglycan is a polymer composed of modified sugars cross-linked by short polypeptides. In effect, the cell wall traps the crystal violet in the cytoplasm, concealing the red dye safranin in gram staining experiment. Certain gram positive species have virulent strains that are resistant to one or more drugs. Gram negative bacteria on the other hand are composed of lipopolysaccharides (LPS), porin channels, and murein lipoprotein which is all absent in gram positive bacteria. Their cell wall has less peptidoglycan, but is structurally more complex, with the outer layer composed of lipopolysaccharides. Their cell wall is located between two layers of plasma membrane. Crystal violet in gram negative bacteria is easily rinsed off from the cytoplasm, and the cell appears to be pink or red due to the thin layer of the cell wall. LPS in gram negative bacteria tends...
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