Newly Discovered Neutral Glycosphingolipids in Aureobasidin A-resistant Zygomycetes

Abstract

We found for the first time that Zygomycetes species showed resistance to Aureobasidin A, an antifungal agent. A novel family of neutral glycosphingolipids (GSLs) was found in these fungi and isolated from Mucor hiemalis, which is a typical Zygomycetes species. Their structures were completely determined by compositional sugar, fatty acid, and sphingoid analyses, methylation analysis, matrix-assisted laser desorption ionization time-of-flight/mass spectrometry, and 1 H NMR spectroscopy. They were as follows: Gal␤1-6Gal␤1-1Cer (CDS), Gal␣1-6Gal␤1-6Gal␤1-1Cer (CTS), Gal␣1-6Gal␣1-6Gal␤1-6Gal␤1-1Cer (CTeS), and Gal␣1-6Gal␣1-6Gal␣1-6Gal␤1-6Gal␤1-1Cer (CPS). The ceramide moieties of these GSLs consist of 24:0, 25:0, and 26:0 2-hydroxy acids as major fatty acids and 4-hydroxyoctadecasphinganine (phytosphingosine) as the sole sphingoid. However, the glycosylinositolphosphoceramide families that are the major GSLs components in fungi were not detected in Zygomycetes at all. This seems to be the reason that Aureobasidin A is not effective for Zygomycetes as an antifungal agent. Our results indicate that the biosynthetic pathway for GSLs in Zygomycetes is significantly different from those in other fungi and suggest that any inhibitor of this pathway may be effective for mucormycosis, which is a serious pathogenic disease for humans.

Incorporation of UDP-Galactose and UDP-GalNAc into midgut tissue of Plutella xylostella (Lepidoptera: Yponomeutidae), which are susceptible and highly resistant to Bacillus thuringiensis Cry1Ac

“…In this research we found more radiolabeled triand tetra-saccharylceramide than mono-and disaccharylceramide, and this tendency closely resembled the synthetic pattern of the neogala-series saccharylceramide (Aoki et al, 2004), supporting our assumption.…”

“…These saccharides were specifically found in flatworms, platheliminthes, such as tapeworm and round worm, and in annelida, such as earthworms (Dennis et al, 1992;Hada et al, 2001). Recently, however, these oligosaccharides were also discovered in zygomycetes such as Rhizopus (Aoki et al, 2004) and thus they are much more widely distributed than had originally been thought. To our knowledge, there is no report showing the neogala-series saccharylceramide in lepidopteran insects, but as mentioned above, it is not surprising that they exist in insects.…”

Glycosphingolipids as a Possible Signature of Microbial Communities in Activated Sludge and the Potential Contribution of Fungi to Wastewater Treatment under Cold Conditions

“…These include 9-Me d18:2-h16:0 and 9-Me d18:2-h18:0, which have been reported to be a major ceramide moiety of CMS from fungi, [26][27][28][29] and 9-Me d18:2-h18:1, which was found in Sporothrix schenckii and Histoplasma capsulatum by Tolendo et al 30,31) Aoki et al reported that Zygomycetes species produce a new group of neutral GSLs with 1-6 or 1-6 galactoside linked to phytoceramides instead of glycosylinositolphosphoceramide, which was found in all fungi, although the CMS detected was GlcCer (9-Me d18:2-h16:0). 32) By observation of glycolipid patterns in activated sludge monthly through 1 year, we noticed that high polar GSLs assumed to possess the oligosaccharide chain tended to increase in the cold period. Such GSLs are not prevalent in fungi, except for Zygomycetes, as reported by Aoki et al, 32) and Mucor sp.…”

“…32) By observation of glycolipid patterns in activated sludge monthly through 1 year, we noticed that high polar GSLs assumed to possess the oligosaccharide chain tended to increase in the cold period. Such GSLs are not prevalent in fungi, except for Zygomycetes, as reported by Aoki et al, 32) and Mucor sp. was isolated from activated sludge collected in January, but not from sludge in May in the present study.…”

The Diversity of O-Linked Glycans Expressed during Drosophila melanogaster Development Reflects Stage- and Tissue-specific Requirements for Cell Signaling

“…After removing the acid by evaporation under a nitrogen stream, the hydrolyzates, containing both monosaccharide alditols (original reduc-ing terminus) and monosaccharide aldoses (internal and nonreducing terminal residues), were acetylated with 0.5 ml of pyridine:acetic anhydride (1:1 (v/v)) at 100°C for 10 min (54). The resulting monosaccharide aldose and alditol acetates were analyzed by gas chromatographymass spectrometry (GC-MS; see below for conditions).…”