No, PNGase A requires that the glycoprotein be at least mildly reduced prior to deglycosylation. We recommend using PNGase A with only DTT at a final concentration of 40 mM. The reaction should be heated at 55°C for 10 minutes and then cooled before adding the PNGase A.  Increasing the amount of PNGase A or the length of incubation at 37°C may be necessary to achieve full deglycosylation.