Mycobacterium tuberculosis polysaccharides from

Mycobacterium tuberculosis, polysaccharides from, Maurice Stacey s work. 7-8... 

In the late 1940s Stacey, with the able and enthusiastic assistance of Paul Kent, examined polysaccharide material from Mycobacterium tuberculosis human strain. From heat-killed cells, two stable, serologically specific polysaccharide fractions and a degraded bacterial glycogen were isolated and examined. 

It is only comparatively recently that D-arabinose has been found to be a constituent of natural products in contrast to the frequent occurrence of its enantiomorph. Units of D-arabofuranose have been shown to form part of the molecules of the polysaccharides isolated from Mycobacterium tuberculosis (human strain),28 being identified as methyl 3,5-dimethyl-D-arabofuranoside in the products of hydrolysis, after methylation, of the somatic polysaccharide, and as the above glycoside and the methyl trimethyl-D-arabofuranoside in the lipid-bound fraction. 2-Methyl-D-arabinose has been synthesized. 

Many polysaccharides contain L-rhamnose as a constituent, and various methylated L-rhamnoses have therefore been isolated by the hydrolysis of methylated gums and mucilages. For example, trimethyl-L-rhamnopyranose has been isolated from methylated gum arabic86 and from the methylated polysaccharide from the somatic portion of the cells of Mycobacterium tuberculosis,26 and in both these polysaccharides L-rham-nopyranose residues evidently occupy terminal positions in the molecule. 

Mycobacterium tuberculosis. Many polysaccharides from this organism have been studied10 and have been isolated from the culture medium, the somatic portion of the cell, and the cell lipoids. Only in a few cases have the structures been definitely established. 

Boyden and Sorkin, in an excellent review on antigens of Mycobacterium tuberculosis, think that it is still not completely clear whether antibodies are formed against any of the lipid molecules, as distinct from polysaccharide or protein components of lipidic complexes. ... 

Polysaccharides which resemble animal glycogens in chemical and physical properties have been isolated from bacterial cells, including avian and human strains of Mycobacterium tuberculosis and surface cultures of enteric bacteria (for example, Escherichia coli and Salmonella monte-video), and also from yeasts. ... 

Isol. from hydrolysate of polysaccharides from Mycoplasma mycoides and Mycobacterium tuberculosis. 

The chemistry and immunostimulant properties of the cell walls of mycobacteria and related organisms have been reviewed. Concanavalin A has been shown to react with three antigenic polysaccharides present in culture filtrates of Mycobacterium tuberculosis, these polysaccharides were isolated by direct precipitation and affinity chromatography. A mannan esterified with succinic acid has been isolated from extracts of mesosomal and plasma membranes of Micrococcus lysodeikticus The polysaccharide was precipitated by concanavalin A, but it was attacked only slightly by jack-bean a-mannosidase. I.r. spectroscopy indicated the presence of both esterified and free carboxy-groups in the mannan. Mesosomal membranes isolated from M. lysodeikticus, unlike preparations of plasma membranes, were unable to catalyse the incorporation of D-[ C]mannose from GDP-D-[ C]mannose into the mannan it appears that the membrane system is unable to synthesize the carrier lipid undecaprenyl D-mannosyl phosphate. It was suggested that the juxtaposition of the mesosomal vesicles and the enveloping plasma membrane in vivo allows the mannan located on the mesosomal vesicles to accept D-mannosyl units from the carrier lipid located in the plasma membrane. 

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