<prompt> Organism with sterols in their cell wall is:MycoplasmaBacillusStreptococcusSpirillum  <response>: Ans: a Mycoplasma Ref: Ananthanaryan, ed, p. 395Mycoplasma lack 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 pleomomorphic 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, eatons media Colonies biphasic with a fried egg appearance CF: Primary atypical pneumonia. Bullous myringitis. Otitis Lab diagnosis:1. Isolation of organism - from throat swab, respiratory secretion2. serological diagnosis -1. Specific - HI, IF. metabolic inhibition2. Nonspecific- streptococcus MG3. Cold agglutinationTreatment: 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 penicillinRemember Ureoplasma 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. 