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Name: Andrew J Langley
Status: Student
Age: 20s
Location: N/A
Country: N/A
Date: N/A
Question:
Why do gram negative bacteria get more damaged when freeze-dryed, due to leakage of cellular components, when their cell wall is less permiable than that of a gram positive bacteria ? Is something to do with the thinner cell wall in positive organisms or to do with the amount of fatty acids, which are damaged during sublimation of water when freeze-dryed?


Replies:
Actually, the gram positive organism has a stronger cell wall than gram negative. The gram positive cell wall is mostly peptidoglycan, a sugar-protein mix, that is cross-linked like a chain-link fence. Gram negatives also have it but a much thinner layer. Their cell wall is more complicated with lipopolysaccharide and proteins, but the strength is in the peptidoglycan.

vanhoeck


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