Discrimination between Sporothrix schenckii and Ceratocystis stenoceras rhamnomannans by proton and carbon-13 magnetic resonance spectroscopy

Abstract

The proton and (13)C magnetic resonance (CMR) spectra of 10 Sporothrix schenckii and three Ceratocystis stenoceras rhamnomannans were studied. On the basis of their CMR spectra, the rhamnomannans from S. schenckii strains could be classified into two major types, I and II, readily distinguishable from the polysaccharides formed at the same temperature (25 C) by C. stenoceras. Rhamnomannans from S. schenckii synthesized at 37 C gave CMR spectra (type III) differing from those of polysaccharides of types I and II and from those of C. stenoceras polysaccharides. The contention that C. stenoceras might be the perfect form of S. schenckii is not supported by the present data. A presumptive pathogenic mutant of C. stenoceras synthesized a type I rhamnomannan characteristic of S. schenckii, clearly differing from the rhamnomannans from C. stenoceras synthesized in the same conditions. Nuclear magnetic resonance spectroscopy revealed differences in the structures of the polysaccharides from these species not previously recognized by methylation analysis.