Fig 2.
Phosphopantetheinylation of IacP on serine 38. MALDI-TOF mass spectrometry of purified IacP_CBP (black line) and IacPS38T_CBP (gray line). The lower molecular mass (14,265.6 Da) indicated for the major gray peak corresponds to the mass of the intact IacPS38T_CBP protein ([M + H]+ theoretical mass of 14,266.3 Da for apo-IacPS38T_CBP), while the higher molecular mass (14,589.6 Da) indicated for the major black peak corresponds to the mass of the intact IacP_CBP protein onto which a 4′-PP prosthetic group had been attached ([M + H]+ theoretical mass of 14,591.5 Da for holo-IacP_CBP).