The P histo-blood group-related glycosphingolipid sialosyl galactosyl globoside as a preferred binding receptor for uropathogenic Escherichia coli: Isolation and structural characterization from human kidney

The P histo-blood group-related glycosphingolipid, sialosyl galactosyl glob oside (SGG), has recently been implicated as a preferred binding receptor f or uropathogenic Escherichia coli [Stapleton, A. E,, Stroud, M. R., Hakomor i, S., and Stamm, W. E, (1998) Infect. Immun. 66, 3856-3861], We report her e the purification and complete structural characterization of SGG from nor mal human kidney. Using metabolically [S-35]-labeled E, coli as a probe, a monosialylated glycosphingolipid was isolated to homogeneity, The glycosphi ngolipid was purified by a combination of high-performance liquid chromatog raphy and preparative high-performance thin-layer chromatography and its st ructure unambiguously elucidated by H-1 NMR, electrospray ionization mass s pectrometry, and methylation analysis, Its primary structure was shown to b e identical to a previously characterized, developmentally regulated, globe -series glycolipid thought to be unique to human teratocarcinoma. The signi ficance of this structure as a unique receptor in human kidney for uropatho genic E. coli and its role in the pathogenesis of urinary tract infections are discussed.