Possible monosaccharide composition of glycopolymers located on the external side of membranes of cells of some mollicutes.

Monosaccharide composition of glycopolymers of five mollicutes (Mycoplasma pneumoniae FH, M. hominis PG 21, M. fermentans PG 18, Acholeplasma laidlawii PG 8 and A. laidlawii var. granulum 118) integrated with their membrane has been studied by means of nine plant lectins with certain carbohydrate specificity labelled with colloid gold. Monosaccharide composition of glycopolymers depends both on the mollicute species and on its capacity to evoke diseases in different microorganisms. Thus genetically relative A. laidlawii PG 8 (saprophytic microorganism) and A. laidlawii var. granulum 118 (an agent of pale-green dwarfness of cereals) have the ratio between N-acetyl-D. galactosamine and N-acetyl-D-glucosamine 2:1 and 1:2, respectively. Large amounts of such exotic sugar as L-fucose have been found in M. hominis PG 21, M. fermentans PG 18 and A. laidlawii PG 8. L-fucose plays the basic role in disguising cells of these mollicutes in human organism (as O(H)-group blood erythrocytes), which permits these mollicutes disseminating through the whole organism. The composition of extracellular glycopolymers of mollicutes is discussed to reveal their role in the processes of adhesion and specialization (organotropism) of these microorganisms in populating the corresponding organs and tissues of macroorganisms.