Cholesterol Requirement of Mycoplasmas

Abstract

Cholesterol requirement for growth of mycoplasmas was tested in a serum-free medium supplemented with albumin, L-arginine, palmitic acid, and various concentrations of cholesterol dissolved in Tween 80. In cases in which Tween 80 was shown to inhibit growth, the test medium was supplemented with cholesterol dissolved in ethanol. Of the 31 species examined, all but Mycoplasma laidlawii, M. granularum, and Mycoplasma species strain S-743 exhibited a growth response to cholesterol. No requirement for cholesterol could be shown with the stable L-phase variants of Streptobacillus moniliformis and Proteus species. The results provide experimental support for the view that the large majority of the established Mycoplasma species require cholesterol for growth. strain designation Mycoplasma salivarium PG-20 M. fermentans PG-18 M. pneumoniae FH M. orale 1 CH 19299 M. orale 2 CH 20247 M. orale 3 DC 333 M. lipophilum MaBy Mycoplasma sp. Navel M. neurolyticum type A M. pulmonis PG-34 M. arthritidis PG-6 M. bovigenitalium PG-11 M. bovirhinis PG-43 M. hyorhinis BTS-7 M. mycoides var. capri PG-3 M. canis PG-14 M. maculosum PG-15 M. edwardii PG-24 M. felis Cat 27 M. gallisepticum S6 M. gallinarum PG-16 M. iners 640 M. meleagridis 886 M. anatis 1340 M. laidlawii PG-8 M. granularum BTS-39 Mycoplasma sp. S-743

Acholeplasma axanthum, sp. n.: a New Sterol-Nonrequiring Member of the Mycoplasmatales

“…Placement of these strains in the family Acholeplasmataceae rests on their growth in the absence of cholesterol (13). Recent and more extensive tests have confirmed the lack of cholesterol requirements for growth of these strains (10). Classification of the S-410 and S-743 cultures as a new species in the genus Acholeplasma is dependent on their unique biological and serological properties reported here and in the earlier study (13).…”

“…axanthum strains are clearly distinct in a number of important biological properties from the two other sterol-nonrequiring mycoplasmas, A. laidlawii and A. granularum. Studies on the cholesterol requirements of the newly described strains (10,13) showed that, although they were able to grow in a serum-free medium, the amount of growth was rather poor when compared to that obtained with other sterol-nonrequiring strains. The remarkable increase in growth of A. axanthum that occurred when Tween 80 was added to the serum-free medium indicated that these strains required an additional source of essential fatty acids.…”

“…However, growth of A. laidlawii depended on the supply of Tween 80 in a partially defined medium containing lipid-extracted bovine serum albumin (9). The response of A. axanthum strains to Tween 80 was instrumental in showing that the sterol requirement of mycoplasmas could not be adequately determined after several passages in a serum-free medium, and that a more detailed test was required (10).…”

“…Recent information on the serological and biological properties of the sterol-nonrequiring mycoplasmas suggests that this group possesses significant differences from the other organisms included in the genus Mycoplasma (2,10,12,13). Accordingly, Edward and Freundt (5, 5a) have proposed the establishment of the new family Acholeplasmataceae and genus Acholeplasma within the Mycoplasmatales for those species without cholesterol requirement for growth.…”

Spiroplasmas are the causal agents of citrus little‐leaf disease

“…(Sigma Chemical Co., St Louis) and supplemented with palmitic acid (10 pg per ml), Tween 80 (0.01 %, v/v) and cholesterol (Iopg per ml) according to the method of Razin & Tully (1970).…”