Atypical bacteria Flashcards
Belong to the class Mollicutes which means ―”soft”
MYCOPLASMA
Mollicutes appear to have evolved from clostridia-loke cells of the gram-positive branch of the
eubacterial tree
MYCOPLASMA
Smallest known free-living forms capable of growing on artificial media
- They have small cell size (0.3 – 0.8 um) and small genome size
MYCOPLASMA
Pleomorphic organisms that do not possess cell wall slow grower, fastidious, facultatively
anaerobic, replicate by binary fission
MYCOPLASMA
bic, replicate by binary fission
o These organisms are bound by a tri-layered membrane that is responsible for
Absolute insensitivity to penicillins
Failure to react with organic dyes used in many stains
MYCOPLASMA
They require sterols for membrane function and growth
MYCOPLASMA
Part of the microbial flora of humans and found mainly in the oropharynx, URT, and
genitourinary tract
MYCOPLASMA
They are common parasites of the genital tract and their transmission is related to sexual
activity
MYCOPLASMA
They lack the enzymatic pathway for purine and pyrimidine synthesis – require complex media
MYCOPLASMA
Eaton agent
- Etiologic agent of primary atypical pneumonia (PAP)/ Walking pneumonia
Mycoplasma pneumoniae
- Pleuropneumonia-like organism (PPLO)
Mycoplasma pneumoniae
Doe not occur as a normal commensal
- Primarily a respiratory tract pathogen and extremely fastidious
Mycoplasma pneumoniae
Can occur singly or as outbreaks in closed populations such as families and military recruit
camps, also causes tracheobronchitis
- This organism infects children and adults and is spread by respiratory droplets produced by
coughing
Mycoplasma pneumoniae
A surface parasite – colonizes the mucosa of the respiratory tract
Mycoplasma pneumoniae
It has gliding motility which allows penetration of organism through respiratory secretions
Mycoplasma pneumoniae
responsible for attachment and interacts with neuraminic acid-containing
glycoproteins
P1 protein
- they produce hydrogen peroxide and ammonia as waster products, and damage respiratory and
urogenital epithelial system
Mycoplasma pneumoniae
- they produce hydrogen peroxide and ammonia as waster products, and damage respiratory and
urogenital epithelial system
Mycoplasma pneumoniae
venereal transmission causing non-gonococcal urethritis
o has been linked to amnionitis, fetal wastage and congenital pneumonia
Ureaplasma urealyticum
the T-strain of the mycoplasma (tiny)
o It has the ability to metabolize urea – produces urease which is considered to be unique
for the mycoplasmas
o When grown in the presence of manganous sulfate with 1% urea, they will develop
minute golden brown colonies
Ureaplasma urealyticum
the T-strain of the mycoplasma (tiny)
o It has the ability to metabolize urea – produces urease which is considered to be unique
for the mycoplasmas
o When grown in the presence of manganous sulfate with 1% urea, they will develop
minute golden brown colonies
Ureaplasma urealyticum
Genital mycoplasma
- They cause invasive disease in immunosuppressed patients (agammaglobulinemia), prostatitis,
bacterial vaginosis, non-gonococcal urethritis (NGU)
Ureaplasma urealyticum and Mycoplasma hominis
The AIDS associated mycoplasma where the organism my play a role, possibly a second
invader
Mycoplasma incognitus
“dark brownish clumps”
A7 to A8 agar medium;U. urealyticum
“fried egg colonies”
M. pneumoniae
urease (-); colonies can be stained with the Dienes or Acridine orange
M. hominis
e can be incorporated int media to detect U. urealyticum and M.
hominis
Urea and/or arginine
Rapid identification for Ureaplasma urealyticum
Manganous chloride test
