Would an acid fast organism be gram positive or gram negative?

Answer 1

Acid fast organism would be gram positive.

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The above answer is incorrect. Acid-fast bacteria would be "gram negative."

Bacteria such as these have very different cell walls which contain a great deal of waxy material, although they still contain peptidoglycan. This waxy material prevents stain penetration, rendering the cell invisible.

Since these acid-fast bacteria are not stained by Gram's Stain Method they have been characterized as "gram negative."

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Heres what the text book says. This is a tricky question based on opinion.

"Their cell walls are unique among the gram-positive bacteria because they consist of other layers in addition to peptidoglycan. An important component of their walls is a group of fatty acids called mycolic acids. Some have proposed that the mycolic acids form a bilayer structure that is analogous to the outer membrane of gram-negative bacteria."

So answer one is technically correct but they characteristics as those of gram negative cells (answer 2).

Page 58

Prescott's Microbiology

Edition: 8th

Author(s):

Willey; Sherwood; Woolverton

ISBN13:

9780073375267

ISBN10:

0073375268

Format:

Hardcover

Pub. Date:

1/1/2010

Publisher(s):

MCGRAW HILL

Answer 2

An acid-fast organism would be gram positive. Acid-fast staining is used to detect organisms that have a waxy lipid layer in their cell walls, which prevents the decolorization step in the Gram staining process. This lipid layer is typically found in gram-positive organisms like Mycobacterium species.

Answer 3

gram positive

Answer 4

it would be a lilac sort of colour