exotoxin

Virulence factors of Group-A Streptococcus

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Streptococcus are gram positive, catalase negative cocci. Are spherical or ovoid, 0.5-1µ in diameter, arranged in chains, non-motile and non-sporing. They may become gram negative in ageing culture when the bacteria die. Some of the strains possess capsules made up of hyaluronic acid while some of the strains possess capsules composed of polysaccharide. Human beings … Read more

Differences between exotoxin and endotoxin

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S.N   Exotoxin Endotoxin 1. It is released outside the cell. It is present inside the cell membrane and released only when the cell lyse. 2.  It is proteinous in nature. It is lipoproteinous  in nature. 3  It is heat labile generally. It is heat stable generally. 4 It is mostly secreted by gram positive … Read more