The structure of nephritogenoside

Nephritogenoside is a minor component of the basement membrane of normal animals (including humans). It is a glycopeptide with the ability to induce chronic progressive glomerulonephritis (end stage kidney) when administered as a single footpad injection, and contains a novel carbohydrate-peptide linkage. The total chemical structure was investigated. It was revealed that nephritogenoside is a simple glycopeptide composed of three glucose residues [alpha-Glc-(1----6)-beta-Glc-(1----6)-Glc] and twenty-one amino acids [1Asn-Pro-Leu-Phe-5Gly-Ile-Ala-Gly-Glu-10Asp-Gly-Pro -Thr-Gly-15Pro-Ser-Gly-Ile-Val-20Gly-21Gln], and that the glucose residues are linked alpha-N-glycosidically to the N-terminal amino acid.