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Rhamnose biosynthesis in mycoplasmas requires precursor glycans larger than monosaccharide.

ABSTRACT: Despite the apparent absence of genes coding for the known pathways for biosynthesis, the monosaccharide rhamnose was detected in the d configuration in Mycoplasma pneumoniae and Mycoplasma pulmonis, and in both the d and l configurations in Mycoplasma arthritidis. Surprisingly, the monosaccharide glucose was not a precursor for rhamnose biosynthesis and was not incorporated at detectable levels in glucose-containing polysaccharides or glycoconjugates. In contrast, carbon atoms from starch, a polymer of glucose, were incorporated into rhamnose in each of the three species examined. When grown in a serum-free medium supplemented with starch, M.?arthritidis synthesized higher levels of rhamnose, with a shift in the relative amounts of the d and l configurations. Our findings suggest the presence of a novel pathway for rhamnose synthesis that is widespread in the genus Mycoplasma.

SUBMITTER: Jordan DS

PROVIDER: S-EPMC3771393 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Rhamnose biosynthesis in mycoplasmas requires precursor glycans larger than monosaccharide.

Jordan David S DS Daubenspeck James M JM Dybvig Kevin K

Molecular microbiology 20130719 5

Despite the apparent absence of genes coding for the known pathways for biosynthesis, the monosaccharide rhamnose was detected in the d configuration in Mycoplasma pneumoniae and Mycoplasma pulmonis, and in both the d and l configurations in Mycoplasma arthritidis. Surprisingly, the monosaccharide glucose was not a precursor for rhamnose biosynthesis and was not incorporated at detectable levels in glucose-containing polysaccharides or glycoconjugates. In contrast, carbon atoms from starch, a po ...[more]

PMID: 23826905

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