[Sialylation of N-carbohydrate chains of glycoproteins with immobilized trans-sialidase from Trypanosoma cruzi]. / Sialilirovanie N-uglevodnykh tsepei glikoproteinov s pomoshch'iu immobilizovannoi trans-sialidazy Trypanosoma cruzi.

Alpha2,3-sialylation of the lactosamine type N-glycans with trans-sialidase from Trypanosoma cruzi is reported. Trans-sialidase (160 kDa, pI 5.35-5.65) and its catalytic fragment (70 kDa, pI 6.0-6.3) were isolated from T. cruzi cells and immobilized on ConA-Sepharose. The resulting preparation retained activity for several months and was repeatedly used for obtaining mono-, di-, tri-, and tetrasialylated 7-amino-4-metylcoumarine-labeled oligosaccharides with various numbers of antennas and for alpha2,3-sialylation of glycans within glycoproteins and neoglycoconjugates.

[Surface enhanced Raman spectroscopy for characterization of structural characteristics of carbon chains in alpha1-acid glycoprotein and pseudoglycoproteins]. / Osobennosti strukturnoi organizatsii uglevodnykh tsepei v alfa1- kislom glikoproteine i psevdoglikoproteinakh po dannym spektroskopii gigantskogo kombinatsionnogo rasseianiia.

Surface-enhanced Raman scattering (SERS) spectroscopy was used to study the structure of carbohydrate chains in glycosylated forms of alpha 1-acid glycoprotein (AGP) and in pseudoglycoproteins obtained by transferring the carbohydrate chains of AGP to a polyacrylamide carrier. It was found that AGP-D glycoform and pseudoglycoproteins containing three or more glycans per molecule, which possess high immunomodulating activity, have a specific spatial organization of carbohydrate chains. This organization is maintained by the interaction of neighboring glycans with each other and does not depend on the nature of the carrier (whether it is polypeptide or polyacrylamide).