Native and/or asialo- Tamm- Horsfall glycoproteins Sd (a+) are important receptors for TRITICUM VULGARIS ( wheat germ) agglutinin and for three toxic lectins (abrin- a, ricin and mistletoe toxic lectin- I)

Journal/Book: FEBS Letters 371 (1), 32-34. 1995;

Abstract: The binding properties of human Tamm-Horsfall Sd(a+) urinaryglycoprotein (THGP) and asialo-THGP with Triticum vulgarisagglutinin(WGA) and three toxic lectins (abrin-a, ricin, and Mistletoetoxic lectin-I) were investigated by quantitative precipitin andprecipitin inhibition assays. Both glycoproteins reacted strongly withabrin-a, precipitating over 80% of the lectin nitrogen tested. THGP alsobound well to mistletoe toxic lectin-I and precipitated 86% of thislectin added, while the precipitability of its asialo product decreasedby 28%. The native glycoprotein completely precipitated the WGA added,but its reactivity was reduced dramatically after desialylation. On thecontrary, the poor reactivity of THGP with ricin increased substantiallyafter removal of sialic acid and completely precipitated the lectinadded. The glycoprotein-lectin interactions were inhibited by one orseveral of the following haptens, p-NO2-phenyl alpha GalNAc,p-NO2-phenyl beta GalNAc, Gal beta 1--> 4GlcNAc, Gal beta 1--> 4Glc,GlcNac beta 1--> 4GlcNAc and/or GlcNAc. From the above results, it isconcluded that native and/or Tamm-Horsfall glycoproteins serve asimportant receptors for these three toxic lectins and for WGA. Author.

Keyword(s): ABRIN/ME (metabolism)

Zurück | Weiter