MYCOBACTERIA

Question 1

Cell wall component of Mycobacteria is distinct to other bacteria, in that it contains _________ instead of N-acetylmuramic acid

Answer 1

N-glycolylmuramic acid

Question 2

Method of staining for Mycobacteria

Answer 2

AFB (acid fast staining )

First stain- carbol fuschin (red)

Question 3

Characteristic of Most mycobacteria that enables them to retain color of the fuschin dye used in staining

Answer 3

• Resistant to decolorization by acidified alcohol (3% HCL)

Question 4

Incubation period for Rapid- growing mycobacteria

Answer 4

sooner than 7 days after subculture to lowenstein-Jensen medium

Question 5

Imcubation period for Slow-growing mycobacteria

Answer 5

later than 7 day

• usually formation of visible colonies is 2-60 days at optimum temp.

Question 6

The clumping and slow growth of Mycobacteria organisms is due to

Answer 6

• hyrophobic cell surface

- this hydrophobicity causes organism to clump so that nutrients are not easily allowed into the cell.