An organism with sterols in their cell wall is
“Mycoplasma lacks a rigid cell wall and they are bounded by a triple-layered unit membrane that contains sterols.
” Mycoplasma PPLO - by Nocard & Roux • Smallest free-living organism • Gram-negative.highly pleomorphic organism,
stained by Giemsa • Found in the form of elementary bodies & filaments of various size • Facultative anaerobe, require a source of cholesterol for growth
• Media = hayflick media, Eaton's media • Colonies = biphasic with a fried egg appearance • C/F: Primary atypical pneumonia. Bullous myringitis.
Otitis • Lab diagnosis: 1. Isolation of organism - from throat swab, respiratory secretion 2. serological diagnosis -1.
Specific - HI, IF. metabolic inhibition 2. Nonspecific- streptococcus MG 3.
Cold agglutination Treatment: DOC- Erythromycin (Presence of 70 S ribosome makes it susceptible to antibiotics that inhibit protein synthesis;
but due to the lack of cell wall they are resistant to penicillin) Remember
• Ureaplasma ureolyticum belongs to the family mycoplasmatacea; which can hydrolyse urea & is a cause for nongonococcal urethritis •
L forms of bacteria - are due to the loss of bacteria but they retain the biochemical & antigenic properties of present bacteria.
Mycoplasma
Bacillus
Streptococcus
Spirillum