Polar lipids of Aspergillus fumigatus, A. niger, A. nidulans, A. flavus and A. terreus.

Little is known of the phospholipid composition of Aspergillus species. The aim of this study was to determine individual phospholipid analogues in Aspergillus. Twenty-nine clinical and environmental isolates from five Aspergillus species were analysed. Fast atom bombardment mass spectrometric data were considered in two ranges, m/z 190-500 and m/z 500-1000, to facilitate the recognition of major fatty acyl groups and phospholipids. Quantitative comparison of major anions in both m/z ranges was undertaken. Confirmation of major phospholipid anions from eight representative isolates was achieved by tandem mass spectrometry. The major phospholipid families were phosphatidic acid (PA), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidylserine (PS). Anions were detected consistent with the presence of specific phospholipid moieties, such as palmitoyl-linolenoyl phosphatidic acid, palmitoyl-oleoylphosphatidylethenolamine, oleoyl-linoleoyl-phophatidylserine and palmitoyl-linoleoyl-phosphatidylinositol. It appears that there is some commonality of sn1 or sn2 fatty acyl substituents, frequently C18:2 at sn1 accompanied by C16:0 at sn2, with differing molecular weights being attributable to analogues with differing head groups. Differences in certain phospholipids (e.g. minor peak with m/z 933) were detected between A. fumigatus, A. nidulans and other species examined which could have diagnostic value.