539. The extracellular mannan of Penicillium charlesii G. Smith

Abstract

Growth of Penicillium charlesii G. Smith on a medium containing D -glucose gave an extracellular galactan and mannan. Selective hydrolysis of the galactan component with O-OlS~-sulphuric acid led to the isolation of the mannan. It was electrophoretically homogeneous and contained eight D-mannopyranosyl units. Hydrolysis of the methylated mannan gave 2,3,4,6-tetra-O-methyl-~-mannose (2 parts), 3,4, 6-tri-O-methyl-~-mannose (5 parts), and 3,4-di-O-methyl-~-mannose (1 part). Hence the mannose units are joined together by 1,2-linkages, with a branching point at C(s) of one of these units. Periodate oxidation confirmed these structural features and suggested that there are four D-mannopyranosyl units on either side of the 1,6-linkage, as in (I).PERIODATE oxidation methods li2 have been developed for investigating, on a semimicroscale, the interglycosidic units present in oligosaccharides, with a view to their subsequent application to polysaccharides, in particular those isolated in small yield by microbiological procedures. These methods have now been applied, in conjunction with the methylation method, to the mannan3 of low molecular weight produced in the culture medium of

Polysaccharides

“…charlesii on a medium containing D-glucose gives an extracellular galactan and mannan (87). charlesii on a medium containing D-glucose gives an extracellular galactan and mannan (87).…”

The Water-Soluble Polysaccharides of Dermatophytes: Iii. A Galactomannan From Trichophyton Interdigitale

“…The above conditions have been shown (7) to effect the selective hydrolysis of galactofuranose residues without affecting the considerably more stable mannopyranose residues. I t is considered that the mannan I retains the main structural features of galactomannan I.…”