Toledo M S, Levery S B, Straus A H, Takahashi H K
Department of Biochemistry, Universidade Federal de São Paulo/Escola Paulista de Medicina, SP, Brazil.
FEBS Lett. 2001 Mar 23;493(1):50-6. doi: 10.1016/s0014-5793(01)02275-x.
Acidic glycosphingolipid components were extracted from the yeast form of the dimorphic mycopathogen Sporothrix schenckii. Two minor and the major fraction from the yeast form (Ss-Y1, -Y2, and -Y6, respectively) have been isolated. By a combination of 1- and 2-D 1H-nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and gas chromatography/mass spectrometry (GC/MS), Ss-Y6 was determined to be triglycosylinositol phosphorylceramide with a novel glycan structure, Manalpha1-->3Manalpha1-->6GlcNH(2)alpha1-->2Ins1-P-1Cer (where Ins=myo-inositol, P=phosphodiester). While the GlcNH(2)alpha1-->6Ins1-P- motif is found widely distributed in eukaryotic GPI anchors, the linkage GlcNH(2)alpha1-->2Ins1-P- has not been previously observed in any glycolipid. Ss-Y1 and Ss-Y2 were both found to have the known glycan structure Manalpha1-->3Manalpha1-->2Ins1-P-1Cer. Together with the results of a prior study [Toledo et al. (2001) Biochem. Biophys. Res. Commun. 280, 19-24] which showed that the mycelium form expresses GIPCs with the structures Manalpha1-->6Ins1-P-1Cer and Manalpha1-->3Manalpha1-->6Ins1-P-1Cer, these results demonstrate that S. schenckii can synthesize glycosylinositol phosphorylceramides with at least three different core linkages.
从双态致病性真菌申克孢子丝菌的酵母形态中提取酸性糖鞘脂成分。已从酵母形态中分离出两个次要组分和一个主要组分（分别为Ss-Y1、-Y2和-Y6）。通过一维和二维氢核磁共振（NMR）光谱、电喷雾电离质谱（ESI-MS）和气相色谱/质谱（GC/MS）联用分析，确定Ss-Y6为具有新型聚糖结构的三糖基肌醇磷酸神经酰胺，即Manα1→→3Manα1→→6GlcNH(2)α1→→2Ins1-P-1Cer（其中Ins=肌醇，P=磷酸二酯）。虽然GlcNH(2)α1→→6Ins1-P-基序在真核生物糖基磷脂酰肌醇（GPI）锚中广泛分布，但GlcNH(2)α1→→2Ins1-P-连接此前在任何糖脂中均未观察到。发现Ss-Y1和Ss-Y2均具有已知的聚糖结构Manα1→→3Manα1→→2Ins1-P-1Cer。结合之前一项研究[Toledo等人（2001年），《生物化学与生物物理研究通讯》280，19 - 24]的结果，该研究表明菌丝形态表达具有Manα1→→6Ins1-P-1Cer和Manα1→→3Manα1→→6Ins1-P-1Cer结构的GIPC，这些结果表明申克孢子丝菌能够合成具有至少三种不同核心连接的糖基肌醇磷酸神经酰胺。
