An aldehydophosphoglycolipid from Acholeplasma granularum

Structures and properties of acyl diglucosylcholesterol and galactofuranosyl diacylglycerol from Acholeplasma axanthum

Acholeplasma axanthum is one of the few procaryotes, and the only member of the Mollicutes, known to contain phosphosphingolipids. Examination of strain S743 for glycolipids revealed the presence of glucosides of cholesterol and galactosides of glycerol as the predominant glycolipids. The major component is acylated diglucosylcholesterol, followed by monogalactosyldiacylglycerol and monoglucosylcholesterol. The glucose residues of the sterol-based compounds appear to be alpha-linked pyranoses, while the galactose of the glycerol-based lipid is an alpha-linked furanose. The "glycolipid' fraction also contained N-(3-hydroxy)acyl sphinganines with varying degrees of O-acylation. None of these ceramide derivatives was linked to carbohydrate. The major glycolipid, tentatively identified as alpha-D-glucopyranosyl-(1 leads to 3)-(O-acyl)-alpha-D-glucopyranosyl-(1 leads to 3)-cholesterol, along with its deacylated derivative, appears to be the first reported instance of steryl diglycosides among procaryotes, in contrast to the steryl monoglycosides, which are common to other mycoplasmata and some spirochetes.

Origins of the mycoplasmas: sterol-nonrequiring mycoplasmas evolved from streptococci

We report the establishment of a phylogenetic relationship between the sterol-nonrequiring mycoplasmas (Acholeplasma species) and streptococci. Three specific antisera prepared against purified Streptococcus faecalis fructose diphosphate aldolase and glyceraldehyde-3-phosphate dehydrogenase and Pediococcus cerevisiae glyceraldehyde-3-phosphate dehydrogenase were used for comparative enzyme immunological studies; the Ouchterlony double-diffusion technique and the quantitative microcomplement fixation procedure were employed. The reactions obtained provide evidence showing that all seven ACholeplasma species studied (A. laidlawii, A. granularum, A. modicum, A. oculi, A. axanthum. A. hippikon, and A. equifetale) are phylogenetically related to streptococci and that they evolved from streptococci. The data strongly suggest that the acholeplasmas comprise a distinct evolutionary group that has diverged from streptococci belonging to Lancefield group D or N. No reactions were observed between these enzyme antisera and cell extracts from six fermentative Mycoplasma species. These results support the view that mycoplasmas are derived from various bacteria.

Structure of the oligosaccharide chain of lipoglycan from Acholeplasma granularum

The membrane associated lipoglycan from Acholeplasma granularum is a linear oligosaccharide attached to a diacylglycerol. The polymer has a monomeric weight of 20000 and is composed of glucose, galactose, N-acetylglucosamine, N-acetylfucosamine, glycerol and fatty acid esters. The proposed structure of the oligosaccharide chain is 12 repeating units of 9 sugars: Glcp(beta 1 leads to 2)-Glcp(alpha 1 leads to 4)-Glcp(alpha 1 leads to 3,4)-FcNAc(beta 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3,4)-GlcNAc(beta 1 leads to 3,4)-GlcNAc(beta 1 leads to 4)-[Glcp(beta 1 leads to 2)-Glcp(alpha 1 leads to 4)-Glcp(alpha 1 leads to 3,4)-FcNAc(beta 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3,4)-GlcNAc(beta 1 leads to 3,4)-GlcNAc(beta 1 leads to 4)]10-Glcp(beta 1 leads to 2)-Glcp(alpha 1 leads to 4)-Glcp(alpha 1 leads to 3,4)-FcNAc(beta 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3)-Galp(alpha 1 leads to 3,4)-GlcNAc(beta 1 leads to 3,4)-GlcNAc-diacylglycerol. The position of the linkages (3 or 4) on the amino sugars has not been resolved.

Sequence and glycosidic bond arrangement of sugars in lipopolysaccharide from Thermoplasma acidophilum

The lipopolysaccharide from Thermoplasma acidophilum is a linear polymer with the structure [Manp-(alpha 1 leads to 2)-Manp-(alpha 1 leads to 4)-Manp-(alpha 1 leads to 3)]8-Glcp-(alpha 1 leads to 1)-diglycerol tetraether as established by Smith degradation, methylation, acetolysis and CrO3 oxidation.