Analysis of phospholipids from Coxiella burnetii by fast atom bombardment mass spectrometry. A rapid method for differentiation of virulent phase I and low virulent phase II cells

Phospholipids extracted from the Coxiella burnetii strain Nine Mile virulent phase I and low-virulent phase II cells were directly analyzed by fast atom bombardment mass spectrometry (FAB-MS). Constant neutral loss (CNL) scanning mass spectra (MS) were acquired to identify various phospholipids within phospholipid classes. Phospholipids from the phase I C. burnetii cells were much more complex than those from the phase II cells. Moreover, in the latter, the absence of phospholipids of the phosphatidylinositol class could be noticed. The results indicate that CNL scanning of phospholipid samples provides a rapid and simple method for identification of the phase state of the bacterium.