FIG. 6.

MALDI-MS analysis of mutant and wild-type p24 in the presence or absence of α-HGA. (A) Mass spectrum of HIV-1 p24 incubated at 37°C for 24 h and then cleaved with trypsin. (B) Mass spectra of HIV-1 p24 incubated with or without 100 mM α-HGA at 37°C for 24 h and then treated with trypsin. The signal of one of the identified fragment (MYSPTSILDIR; 1,295.72 Da) and another signal (1,367.70 Da) that appeared in its vicinity are highlighted. (C and D) MS/MS spectra of 1,295.72 and 1,367.70, respectively, showing the y- and b-ion series identified, suggesting that these signals originate from the same peptide fragment.