13mannose

13mannose is a term used in scientific literature to refer to isotopically labeled forms of the monosaccharide mannose, typically with one or more carbon-13 atoms. It is not a distinct natural metabolite, but rather mannose molecules that carry the stable isotope 13C to enable tracing in metabolic and structural studies. A fully 13C-labeled mannose would contain six 13C atoms, increasing the molecular weight by six daltons; partially labeled forms have correspondingly fewer labeled carbons. Such labeling is commonly used in mass spectrometry and nuclear magnetic resonance experiments to differentiate the administered sugar from endogenous pools and to track its incorporation into glycoproteins and polysaccharides.

Synthesis and sources: 13C-labeled mannose can be obtained by chemical synthesis from 13C-labeled starting materials or produced biologically by cultivating microorganisms on 13C-enriched substrates and subsequently isolating the resulting mannose.

Applications: 13mannose is used as a tracer in studies of glycosylation, glycan biosynthesis, and carbohydrate metabolism. It supports quantitative investigations of pathway fluxes, turnover rates, and the structural composition of glycans by enabling precise tracking of mannose-derived units.

Detection and properties: because the isotopic composition is altered rather than the chemical identity, 13mannose has very similar physical properties to natural mannose. Detection relies on mass spectrometry and 13C NMR, which reveal characteristic mass shifts and resonances corresponding to the labeled carbons.

See also: Mannose, Isotopic labeling, 13C labeling in metabolism.