A recombinant gp145 Env glycoprotein from HIV-1 expressed in two different cell lines: Effects on glycosylation and antigenicity
Fig 2
Positive ion MALDI-ToF analysis of N-glycans released from HIV-1 gp145.
The recombinant gp145 (20 μg) produced in (A-B) CHO-K1 and (C-D) Expi293F cells were incubated overnight with (B and D) and without (A and C) Neuraminidase A (NEUA) at 37°C. Then, gp145 proteins were resolved by SDS-PAGE and the 145 kDa bands were excised. N-glycans were released with PNGase F and were co-crystallized with 2',4',6'-Trihydroxyacetophenone monohydrate (THAP) ionization matrix. The x-axis represents the mass-to charge ratio (m/z) value in Daltons and the y-axis shows the relative abundance (arbitrary units) of the ions. The released glycans were analyzed using the MALDI-ToF reflector positive mode. Predicted glycan structures of the masses shown in the upper panel spectrum are the same as those shown in the spectrum on the lower panel.