Mannosidostreptomycin streptomycin

In addition to the above modifications of the streptomycin structure there exists a fourth compound, mannosidostreptomycin (streptomycin B), this compound is an a mannoside of streptomycin (Fig. 4). 

Streptomycin B (mannosidostreptomycin) has a mannose molecule attached to the methylglucosamine group, and is the first antibacterial product made, but is enzymatically converted to streptomycin later in the fermentation. 

The separation of aminodeoxy sugars from neutral and acidic sugars may be readily achieved using an acetate buffer at pH 5 (the iV-acetyl derivatives of D-glucosamine and n-galactosamine have characteristic Mg values in borate buffer at pH 10). M. C. Foster and Ashton have found zone electrophoresis to be useful in the separation of streptomycin components. They observed the following mobilities X 10 ) streptomycin, 22.5 mannosidostreptomycin, 19.5 streptothricin, 24.0 streptidine, 24.9 and streptamine, 6.3. 

Mannosidostreptomycin, a biologically active analog, according to a recent report. is not adenylated by a kinase capable of inactivating streptomycin. Intriguingly. adenosine, as well as the C-nucleoside formy-cin is a competitive inhibitor of ATP which serves as phosphate donor in the inactivation of kanamycin by a phosphorylase of aeruginosa. ... 

It is of interest that a mutant strain of S. griseus has been isolated which produces httle mannosidostreptomycin (5 % of total). This mutant strain was derived from an initial strain which produced up to 45% of the total streptomycin as mannosidostreptomycin (Alikhanian, 1962). Such evidence favors pathway A rather than B. 

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