Penicillin-G and G neg. bacteria

chmc chmc at
Wed Mar 15 11:43:21 EST 2000

Both gram positive and gram negative bacteria have cell walls made of
peptidoglycan (gram negatives have thinner walls, but it is still
peptidoglycan), so penicillin is effective against either one.

Bacilli are rod shaped bacteria, cocci are spherical, but the composition of
their cell wall is not related to shape.  For example, Niesseria is a gram
negative cocci, streptococcus is a gram positive cocci.


"Gerd " wrote:

> Testing Penicillin-G aganst several strains of bacteria was part of an
> experiment I asked some students to do.
> In their reports some of the students mention that P-G is supposed to be
> active against G+ bacteria, which is obvious, but in addition it's supposed
> to be active against G neg. cocci.
> Anyone having an explanation?
> Personally I do only have teoretical knowledge about P-G, and my knowledge
> about differences between cellwalls of cocci and bacilli is scarse. Could
> anyone explain, please.
> Gerd

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